Hi Guys,
I've done a lot of reading into Caps MAF mod as found here: https://www.spyderchat.com/forums/showthread.php?34825-1-and-2-ZZ-ECU-s-Side-by-Side-Sorta
This mod is not secret and is done but many people with great results by removing the intake vanes and replacing the injectors to yellow 310cc. Within Caps post he indicates that increasing the fuel pressure will increase the fuel delivery much the same as the bigger injectors. This is essential so that in closed loop the ECU get's an adequate AFR reading.
Further reading in to Cap's post his LTFR sit at -7 which tells me the 310cc injectors are over fuelling and it's being corrected in the stock ECU.
As I will soon have other bolt on mods added to my car, my parameters will be different to Caps. I'm looking for a more 'tune-able' solution and I would also like to get my LTFR closer to stock (0). I figured I could achieve this with an adjustable Fuel Pressure Regulator BUT after further research I find that MR2's do not have a fuel return system BUT I understand you can buy non-return FPR's which effectively decrease pressure(?).
SO if I crushed the standard FPR to 60 PSI (max) I would then have the ability to tune for an ideal AFR?
Am I barking up the wrong tree? I think I have the theory nailed but not too sure on the practicalities.
I would love your input on this.
That all makes perfect sense to me other than the reference to the non return FPR reducing pressure. I haven't seen one of these, can you elaborate further? I can't work out how you could reduce the pressure without some form of return line.
Are you sure you need less than 60psi?
To be honest that's what i'm still researching into... I would love to have control over the FPR. It also doesn't seem like I'm able control the pump speed by varying the voltage either :(
If only the MR2 had a fuel return system!
I'm very tempted to buy a Greddy Blue and have a crack at it... but that's another learning curve for another day.
No I think that's right. Basically the standard system has a FPR inside the tank so the pressure coming out of it is fixed by that.
It's not a massive job to convert the system into a return system if you really want one, quite a few people have done it. BUT it is easier to just fit 310cc injectors if you're just after the MAF mod.
Or crush the FPR in little steps until you get the pressure you want.
Few things:
1) maf mod plays with the MAF readings of the car to make it think one thing, and giving it bigger injectors (that it does t know about) to bring things back into balance.
The more tuneable alternative you're looking for is called a standalone ecu or a good piggyback :)
Then you can change the MAF signal and up fueling to achieve the same.
2) LTFT of 0 isn't perse the goal. The stock ECU adjusts fueling also bevause of aging sensors and other components. Forcing it to 0 might actually be making it less efficient.
I suppose the goal of the MAF mod was to increase performance with little expence. It gets you a good way there, although not 'perfect' ...but it's not a problem! I fully understand what you're saying about the fuel trims but my OCD is metaphorically attacking me for accepting your reasoning.
I suppose you're right about the ECU upgrade... oh well, here goes the next few weeks reading up about the greddy units 🙂
Quote from: Optimus prime on August 7, 2018, 23:31
I suppose the goal of the MAF mod was to increase performance with little expence. It gets you a good way there, although not 'perfect' ...but it's not a problem! I fully understand what you're saying about the fuel trims but my OCD is metaphorically attacking me for accepting your reasoning.
I suppose you're right about the ECU upgrade... oh well, here goes the next few weeks reading up about the greddy units 🙂
If you are after a bit of extra performance, don't try and fool the stock ECU, look to reduce the overall weight of the car, its fairly easy to drop a bit of weight from the car - its all about power to weight. Remember that my car is currently on 176k miles.
Here are the results for a few tests whilst drag racing (using it as a yard stick as it relates to acceleration), I have now moved onto a Link Xtreme ECU so my PFC will be up for grabs including maps etc.
Here is my initial baseline run - only mods for this was the decat manifold and drop in filter, was running 100% stock weight, stock tyre pressures:
2.2833 second 60 foot
15.8627 second 1/4 mile
86.86mph terminal
Best run on the stock ECU with around 60kg weight saving (will work out the exact amount later) although was still running 2/3 of a tank, stock tyre pressures:
2.1302 second 60 foot (best 60 foot was a 2.0917)
15.1987 second 1/4 mile
88.39mph terminal
I then plugged in my partly tuned PFC - VVTi tweaks, ignition advance, fueling 4k rpm+ was between 12.8 and 13.3 AFR, I have a very very rich midband which I need to tune but each run it only went through these cells once. The timing is still fairly conservative, knock levels are low for the whole map.
Best run:
2.0745 second 60 foot
14.9645 second 1/4 mile
91.41mph terminal
The MAF mod isnt supposed to make the car any faster though.
It's supposed to unleash a bit of midrange torque.
So the rest of the dyno run data would be more interesting. How did it pull in the middle of the 1/4 mile through the gears?
Quote from: shnazzle on August 8, 2018, 07:29
The MAF mod isnt supposed to make the car any faster though.
It's supposed to unleash a bit of midrange torque.
So the rest of the dyno run data would be more interesting. How did it pull in the middle of the 1/4 mile through the gears?
I found that advancing the ignition made a fair bit of difference to throttle response and overall drivability - switching back to the stock ECU the car felt 'soft' in terms of throttle response and felt lacking low down. I have found however that running an air filter behind the battery also freed up some low down torque even on the stock ECU as its a straight shot into the intake rather than round a few bends.
The car is now running on my Link Xtreme and is currently converted over to a MAP sensor - will be looking to remove the MAF completely soon, although still using it for the intake air temp but have a replacement for that to fit soon.
Throttle response is my main problem along with the gear ratios (that's another story for another thread). Personally I think it has enough HP but it's mid-range power is relatively lacking. I'm going to run a few tests and do a few runs when I get back home on Friday just to ensure nothing is wrong. I also plan on installing my induction kit on Friday after my initial tests to see what I get. next month i'll be installing a new manifold (if Hamish gets stock in) and depending on whats left in the bank i'll get some lowering springs.
thanks for the offer on the PFC but as i'll be learning and playing with it i think a piggyback is going to be the safer bet for me, plus i want to keep the immobiliser, AC and other bits.
Quote from: Optimus prime on August 8, 2018, 08:10
Throttle response is my main problem along with the gear ratios (that's another story for another thread). Personally I think it has enough HP but it's mid-range power is relatively lacking. I'm going to run a few tests and do a few runs when I get back home on Friday just to ensure nothing is wrong. I also plan on installing my induction kit on Friday after my initial tests to see what I get. next month i'll be installing a new manifold (if Hamish gets stock in) and depending on whats left in the bank i'll get some lowering springs.
thanks for the offer on the PFC but as i'll be learning and playing with it i think a piggyback is going to be the safer bet for me, plus i want to keep the immobiliser, AC and other bits.
Sounds like you want to invest in a bored out throttle body.
That's where all my direct throttle response came from. Along with the Hurricane intake.
Also, ask @Carolyn (https://www.mr2roc.org/forum/index.php?action=profile;u=22891) for the parts list for her engine head-steady. It doesn't make things any quicker but overall response is better because you don't have to wait for the engine to stop rocking around on its mounts.
An emanage blue can be had for cheap cheap and you can do the appropriate MAF compensation in there for an intake kit,and some timing if you see fit.
You can also achieve the same effect as the larger injectors by telling the emanage that you're running smaller injectors. Same as putting larger injectors in and not telling the ecu.
For what it costs I reckon the MAF mod is worth a try. It seems to be a completely proven option that doesn't mess about with the ECU or cause any MOT emissions problems.
If you do it using the FPR mod it should only cost about £30!
shnazzle - would you have a thread on what you did and your findings? i'm interested!
lamcote - you're right £ for £ the MAF mod seems to be unbeatable.
Quote from: Optimus prime on August 8, 2018, 09:03
shnazzle - would you have a thread on what you did and your findings? i'm interested!
lamcote - you're right £ for £ the MAF mod seems to be unbeatable.
I can't quote any sources unfortunately :) These are just what I've experienced/logged over the years of trying stuff with my car :)
The MAF mod definitely works and is great bang for buck. It's proven by many many people.
I had the kit, I just never installed it because I ended up putting the eManage blue on instead.
Now you're giving me ideas! i'm going to be new to the world of aftermarket ECU's. Could you point me in the right direction? I've been looking at the Greddy blue but not the instillation of it, as i understand it i'll need some harnesses to connect into the factory looms. what should I be looking for? i'll then need a base map etc etc.
Quote from: Optimus prime on August 8, 2018, 16:32
Now you're giving me ideas! i'm going to be new to the world of aftermarket ECU's. Could you point me in the right direction? I've been looking at the Greddy blue but not the instillation of it, as i understand it i'll need some harnesses to connect into the factory looms. what should I be looking for? i'll then need a base map etc etc.
You should be able to pick up a blue for peanuts. It's the harness you need that's expensive, unless you hardwire it in. To be fair, there's not that many wires, it's not that good haha.
but anyway, the Boomslang harness will set you back a fair few pennies.
Best bet is to ask on here to see if anybody has a plug/play piggyback up for sale and go from there.
wouldn't worry about a base map. It's not a standalone. The piggyback only adjusts signals, it doesn't create them. So if you plug it in and leave everything blank, it does nothing. Nice and safe :)
One thing before you start going towards an aftermarket ECU, what sort of power are you planning on and what are your future plans? I only ask as the 1zz with all the bolt ons might get 10-15% above stock including an aftermarket ECU. Whereas swapping out to a 2zz on a stock ECU will be up to around 190bhp.
Basically just saying that after you swap out the intake and exhaust, any further tuning on the 1zz NA gets very expensive for only small gains.
I am building up a forged 1zz to go turbo - aim is around 400bhp, I have upgraded to a Link Xtreme as it has knock control along with many other options, I have invested in the ECU to help protect my investment in the engine. If you plan to stay NA then look at the 2zz swap, if you are wanting forced induction you could look at a turbo on supercharger on the stock 1zz (which will need a better ECU).
Let us know your overall goals for the car in terms of power and use, I will have my 1zz PFC up for sale soonish (currently sitting next to me) which is a standalone ECU vs an EM blue or EMU - be careful with ECU selection though, not all aftermarket ECUs have support for VVTi.
At the moment i'm looking to stay N/A with the 1ZZ. I want to improve throttle response and gain some power. If I could get up to 160 whp that would be amazing but in reality i think 150 whp is more manageable on budget.
I will mainly use the car on the road. I might give a track day a blast but that's not what this car is about for me.
I'm really interested in learning how to configure an ECU which is going to take some time. Yes, i'm fully aware I would get better results with a professional tune but that's not what i'm after.
My ultimate goal would be to create my own 6-7 low boost turbo setup which should yield circa 200 HP from reading other posts (more than enough). As I understand it, this would give me great drive-ability on the road. a SC would be nice but budgets are soon stretched, especially when looking at Rotrex.
Quote from: Optimus prime on August 8, 2018, 19:33
At the moment i'm looking to stay N/A with the 1ZZ. I want to improve throttle response and gain some power. If I could get up to 160 whp that would be amazing but in reality i think 150 whp is more manageable on budget.
I will mainly use the car on the road. I might give a track day a blast but that's not what this car is about for me.
I'm really interested in learning how to configure an ECU which is going to take some time. Yes, i'm fully aware I would get better results with a professional tune but that's not what i'm after.
My ultimate goal would be to create my own 6-7 low boost turbo setup which should yield circa 200 HP from reading other posts (more than enough). As I understand it, this would give me great drive-ability on the road. a SC would be nice but budgets are soon stretched, especially when looking at Rotrex.
That's great to know your goals, certainly very achievable, my suggestion would be:
1zz NA
Intake - filter behind the battery (enclosed)
Decat manifold (removing precats)
Free flowing exhaust (I am running a TTE but its not the lightest)
Minor weight reduction
You can then look to get an aftermarket ECU, which should cover maxxing out the car NA but still have the option to run turbo, you will need additional items such as injectors, possibly clutch along with all of the turbo items. Check out Leethesparky's build or his youtube channel spyderlee and see what he has done, he is running on an E-Manage ultimate, think there is also a group buy for a standalone ECU on this forum as well.
You can see from my drag times that the weight does make quite a difference with only a small amount extra gained from the extra power - I know when I was running my PFC vs the stock ECU it certainly felt more driveable.
I would suggest doing a few cheaper intake and exhaust mods first and then look at doing supporting mods such as the brakes, servicing, any suspension work etc before increasing the power output. Tyre choice make a huge difference, as does the tyre pressures so look at fine tuning the car first to your liking - there are a few simple things you can unbolt to remove weight which will help the overall feel of the car as well which is free performance.
160 Whp is not really going to be achievable from a NA 1zz, certainly not without spending thousands. Even 150 Whp is mega money.
Doesn't Bernie's make around 150 whp? And that's with 170 bhp.
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Yes and how much did that cost?
Then getting another 10 whp for 160 would be eye watering.
Quote from: lamcote on August 8, 2018, 21:21
Yes and how much did that cost?
More than I paid for my car...[emoji23]
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Quote from: lamcote on August 8, 2018, 20:59
160 Whp is not really going to be achievable from a NA 1zz, certainly not without spending thousands. Even 150 Whp is mega money.
Just going on the dyno figures posted up vs as stock power of 140bhp - as mentioned tuning the 1zz NA past bolt ons isn't going to give many gains vs a 2zz swap or LPT.
https://www.mr2roc.org/forum/index.php?topic=27521.0
Quote from: Call the midlife! on August 8, 2018, 21:22
Quote from: lamcote on August 8, 2018, 21:21
Yes and how much did that cost?
More than I paid for my car...[emoji23]
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My Link ECU cost more than my car lol
Yep, ok, my figures are clearly pulled out of thin air then. Obviously peak power is going to be difficult to chase in N/A. From an engine performance perspective i'll crack on with the cheap mods I/M/E and general servicing. If I can get my hands on a cheap set of 2zz injectors i'll do the MAF mod and then turn my attention to the rest of the car for a few months such as suspension, bracing, poly's etc. I will later then revisit ECU (after hours of research) and then chase more power.
The thing is, I reckon "just" getting 150+ flywheel hp would make a huge difference and that is realistic.
Then if you follow the weight loss advice as well you're onto a winner.
A Lamborghini engineer was interviewed the other day and he reckoned a customer would notice the effect of a 10kg weight reduction in a Huracan!
I'm screwed on the weight loss part, apart from the bits I've added to the car itself I probably carry 10-15kg of general shizz around all the time too!
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Ok, I thought I would take the time to lay out what my plans are so you guys get a better idea of what I'm aiming to doing rather than just giving you sporadic information. Thank you all for your very informative posts so far and I really appreciate it coming from people who have actually been there or seriously plan on achieving their own goals.
I'm fairly handy with a spanner and I understand technical info fairly well. I'm lucky I have a mate with a proper garage so I'll be heading over there some weekends.
I've had the MR2 for about 4 weeks, in that time I have;
- Replaced the radiator as it sprung a leak (obviously it's never been driven so hard ;) )
I flushed the system twice and the coolant level is nailed on the max mark, it barely moves at all. And yes, the heaters work! :D
- Flushed engine oil and changed filter
- Replaced spark plugs (I like to do that with new cars I own)
- Changed the standard headlight bulbs as they were appallingly dim.
This weekend I plan on installing my BMC CDA intake with the original MAF housing (already cut out from another air box). I've ordered pipe work that will replace the standard airbox route but I will see if I can mount it behind the battery. As I'm using the standard MAF housing I think it's going to be too big to fit in that space.
Next weekend at the garage I plan on removing the pre-cats. I will also remove and wire brush the sub-frame, give it a spray of anti-rust primer followed by a few coats of hammerite.
Only after I've done the pre-cats I will install the MAF mod as there's speculation that the ECU over fuels at higher rev's to try and preserve the integrity of the pre-cats. No cats means no problems so I should be safe.
I then plan on buying Tein springs (and other recommended parts?) – I will follow this up with a 4 wheel alignment (I want to do this part after the sub-frame to ensure I get the best out of the alignment)
I will then move on to braded brake lines and maybe Green stuff pads but that depends on how much meat is left on the existing pads.
Although I fully appreciate losing weight in the easiest way to get it moving faster but I like all of the comforts – saying that the A/C needs a new rad but that can wait until next year now.
That's enough to keep me busy for a few months and I'll research into the ECU side of things.
What do you guys think, does that sound sensible?
Only comment I'd make there is start soaking your subframe fixings in Plusgas now, like this minute, unless you're confident they're all nice and corrosion free? Same goes for the manifold, three amigos or you could find yourself taking all weekend to do the precats alone.
Probably don't expect to do the subframe in one weekend either if you hit stubborn nuts...
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Sounds great to me. A detailed write up and spec for the intake installation would be great if you get chance?
Quote from: lamcote on August 8, 2018, 22:23
Sounds great to me. A detailed write up and spec for the intake installation would be great if you get chance?
I will certainly try and get this done. I will have to do it in two parts. one replacing the existing box and the other behind the battery at a later date!
That sounds very sensible.
If I were you, stick to your original plan; make small tweaks to improve response. And your plans to make the handling best it can be are spot on.
You may (like me) find that the stock powered mr2 (with a few tweaks) is an absolute joy.
I'm on year 5 I think of stock mr2 power and I still drive it every day with a huge smile.
All of this mad power craving is starting to do my head in a bit.
Don't get me wrong, I love Helen's turbo MR2 (my wife), but it seems like nobody can just love the 2 for what it is anymore.
If I were you; get your intake sorted, maf mod, and maybe look at a bored out throttle body (MaxBore or Streetwerks). Then a good exhaust manifold and all the handling mods.
Enjoy it! :)
Look forward to the progress
Quote from: Call the midlife! on August 8, 2018, 22:02
I'm screwed on the weight loss part, apart from the bits I've added to the car itself I probably carry 10-15kg of general shizz around all the time too!
Sounds like you could do with some carlonic irrigation!!
Quote from: lamcote on August 8, 2018, 22:31
Quote from: Call the midlife! on August 8, 2018, 22:02
I'm screwed on the weight loss part, apart from the bits I've added to the car itself I probably carry 10-15kg of general shizz around all the time too!
Sounds like you could do with some carlonic irrigation!!
Hahahahaha! Nah, regardless of any plans for the future, mods wise, I'll not be doing any weight reducing. Other than the straight line speed, which would take drastic weight loss to improve anyway, the car is plenty quick enough for my current talent through the bends.
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Quote from: Call the midlife! on August 8, 2018, 22:02
I'm screwed on the weight loss part, apart from the bits I've added to the car itself I probably carry 10-15kg of general shizz around all the time too!
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You can easily take off 10kg from the car as seen below for some of the weight I have removed when the car is in 'road trim', more if you remove the radio etc
ECU shield - 0.459kg - really quite pointless and rather heavy
Smaller exhaust manifold heat shield - 0.588kg - not needed if running a decat manifold
Larger exhaust manifold heat shield - 1.202kg - not needed if running a decat manifold
Front floor mats - 1.927kg - heavier than I expected!
Frunk lid - 1.218kg - easy to remove
Frunk plastic cover - 1.4kg - Few poppers to remove this item but means you can also check fluids easier
Engine vanity cover - 0.357kg - No real need for this
Sides of rear bin trims - 0.344kg - these are meant to pop out as standard to allow wider loads in bins (as per OEM instructions)
Rear bin door - passenger - 1.220kg
Rear bin door - driver - 1.205kg
Basic weight reduction - 9.8kg of basic unbolting/lift out items without loss of comfort/looks
If you have a breakdown recovery service also add:
Toolkit - 3.039kg
Spare wheel - 11.2kg
Frunk well - 3.418kg
Frunk under bracket (long) (2) - 0.278kg
Full road trim weight reduction - 27.7kg of weight removed before starting to unbolt trim or remove sound systems etc
Quote from: shnazzle on August 8, 2018, 22:29
That sounds very sensible.
If I were you, stick to your original plan; make small tweaks to improve response. And your plans to make the handling best it can be are spot on.
You may (like me) find that the stock powered mr2 (with a few tweaks) is an absolute joy.
I'm on year 5 I think of stock mr2 power and I still drive it every day with a huge smile.
All of this mad power craving is starting to do my head in a bit.
Don't get me wrong, I love Helen's turbo MR2 (my wife), but it seems like nobody can just love the 2 for what it is anymore.
If I were you; get your intake sorted, maf mod, and maybe look at a bored out throttle body (MaxBore or Streetwerks). Then a good exhaust manifold and all the handling mods.
Enjoy it! :)
Look forward to the progress
I probably would have gone down this route if the engine didn't burn oil, if the stock engine made good power and was reliable in terms of the internals didn't need touching I would have kept the power as is - usually more fun to drive a low power car and use all the power than a higher power car on part throttle. I think my engine build is probably the most extreme of the 'whilst I am in there' fixes! Saying that I will be running my engine NA for the first year or so whilst I select all the turbo parts so it would mean I have a fairly close to stock NA engine but can rev to 8k.
Quote from: m1tch on August 9, 2018, 07:52
Quote from: Call the midlife! on August 8, 2018, 22:02
I'm screwed on the weight loss part, apart from the bits I've added to the car itself I probably carry 10-15kg of general shizz around all the time too!
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You can easily take off 10kg from the car as seen below for some of the weight I have removed when the car is in 'road trim', more if you remove the radio etc
ECU shield - 0.459kg - really quite pointless and rather heavy
Smaller exhaust manifold heat shield - 0.588kg - not needed if running a decat manifold
Larger exhaust manifold heat shield - 1.202kg - not needed if running a decat manifold
Front floor mats - 1.927kg - heavier than I expected!
Frunk lid - 1.218kg - easy to remove
Frunk plastic cover - 1.4kg - Few poppers to remove this item but means you can also check fluids easier
Engine vanity cover - 0.357kg - No real need for this
Sides of rear bin trims - 0.344kg - these are meant to pop out as standard to allow wider loads in bins (as per OEM instructions)
Rear bin door - passenger - 1.220kg
Rear bin door - driver - 1.205kg
Basic weight reduction - 9.8kg of basic unbolting/lift out items without loss of comfort/looks
If you have a breakdown recovery service also add:
Toolkit - 3.039kg
Spare wheel - 11.2kg
Frunk well - 3.418kg
Frunk under bracket (long) (2) - 0.278kg
Full road trim weight reduction - 27.7kg of weight removed before starting to unbolt trim or remove sound systems etc
I know where you're coming from and understand your thought process but mine is a road car that gets driven spiritedly where feasible.
And some of the single track, back roads we've been down lately would be a nightmare to get recovered from for something as simple as lack of a spare tyre.
It's each to their own David, I admire your enthusiasm in pursuing your goals but a semi stripped out car with exposed framework etc just doesn't do it for me.
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My plans have changed!
I personally don't like where I was heading with the BMC. I am sure I could get it looking right and the intake temps reasonable but I wasn't going to end up with what I wanted. So I've gone back to the stock air box for now and looking to sell the BMC to fund other parts of this project. I will later buy a cone filter and install behind the battery.
I'm working in the garage this weekend and will do the following:
De-cat the pre-cats.
Remove and spray the subframe.
Do the MAF mod as I picked up a set of yellow injectors from Rutland MR2.
Wish me luck, i'll tell you how it went.
Oh, before I forget, what have people used as a riser for the MAF. I'm thinking a 5.5mm spacer with some 1mm to 'fine tune' the setup.
It's a long time since I looked at this mod but I think the official spacer had a notch in it to clear an obstruction. A simple spacer might need some work to fit and seal properly, but not sure.
6.35mm was what Cap recommended as ideal.
https://www.google.co.uk/search?q=maf+mod+riser+picture&client=tablet-android-pega&tbm=isch&tbs=rimg:CX1TRyzP1hDGIqAB_1ruNp-qv0d2C51vdPGiLqg7CS-1SXyp3xCITBil9CgBYt47tOYFp5VmPLktLa_1YEdyX9Qe0CGL4fvSTpReGNK3GxjGzCJuRwl46xlsyHUPA2SXHZ7atEsphMgOwvIaOQugq1fguPTl-n4-Js7yZGI-LnJxVrSqF_1gpRYho2TXAiCvPupZK9Vs7fA-FKo0ZVCq4gb5AfpkM1xQNXbSwdmdioSCf67jafqr9HdEY9N8xTcDLlXKhIJgudb3Txoi6oRj03zFNwMuVcqEgkOwkvtUl8qdxEyex_1TkhOJiioSCcQiEwYpfQoAEU8noSCgDopfKhIJWLeO7TmBaeUR4FQWQQPezl8qEglZjy5LS2v2BBGZ5W0rJjXTfioSCXcl_1UHtAhi-EZC8b19zfkRmKhIJH70k6UXhjSsRsX6L7RigUZQqEglxsYxswibkcBHEucbT4CuV8yoSCZeOsZbMh1DwESwp3V0SbEHyKhIJNklx2e2rRLIReKuknEgt1J4qEgmYTIDsLyGjkBHvqJQ2ysRtIyoSCboKtX4Lj05fEY9N8xTcDLlXKhIJp-PibO8mRiMR8FC3zmwMmagqEgni5ycVa0qhfxE82iSkmAUBpSoSCYKUWIaNk1wIEWPih2LGaHYLKhIJgrz7qWSvVbMRb0K942malPsqEgm3wPhSqNGVQhEmOvoyuzy8ICoSCauIG-QH6ZDNEWj9fEh5ekpMKhIJcUDV20sHZnYRJ8P96XKBTA8%3D&tbo=u&ved=2ahUKEwi9waKi3e_cAhXHAcAKHUj9BMoQuIIBegQIARAy#imgdii=jCDrNF0Y-mvBZM:&imgrc=WLeO7TmBaeWHPM:
Quote from: lamcote on August 15, 2018, 19:43
It's a long time since I looked at this mod but I think the official spacer had a notch in it to clear an obstruction. A simple spacer might need some work to fit and seal properly, but not sure.
6.35mm was what Cap recommended as ideal.
The "good" spacer does have a small notch, but many have made spacers from plastic pipe, etc and made them work. The MAF mod is very popular in the US, but it only works properly with the stock airbox, and it mainly just improves the midrange. I have been running it for years, and it does what it is intended to do, which is to "fatten" the midrange in the 3,000 - 4,500 rpm range and pull a bit smoother in that range, particularly at part throttle. It also gives slightly better fuel economy. But as for top HP, a couple have done dyno tests before and after, and the difference at full throttle isn't much. The most reported was a couple HP. Still, it is a cheap modification that does work
I don't think I'm going to get much luck in finding official spacers, I'm going to have to go at it alone. I have been thinking that 30mm plastic piping will do the job, I need to have a play. I have the injectors so that's the 'hard part' out of the way ;)
I will go with the official spacing requirements (1/4") on the stock box and later play with an induction kit located behind the battery.
It would be great if you would provide details about how you get on?
I will keep you guys updated as this mod, although well documented has dried up and finding a UK solution for the spacer is difficult to come by.
Quote from: Optimus prime on August 20, 2018, 09:09
I will keep you guys updated as this mod, although well documented has dried up and finding a UK solution for the spacer is difficult to come by.
I'm not sure if I've asked before but maybe Steve (widermuller) can mill us some.
If we can get an existing one to him. @Dev (https://www.mr2roc.org/forum/index.php?action=profile;u=1962)?
finding the profile of the original is a task... As for the height i'm seeing conflicting opinions/suggestions. 1/4 inch or 5.5mm, that's why i'm thinking about using a 5.5mm spacer and then using washers to fine tune it
Ive found someone who will be able to machine a plastic spacer. Question is, how high should I make it? I will get a couple done so i'm happy to try a range of heights.
I'm sure I saw 6.35mm quoted mainly, however there seems to be some tunability based on the following quote from Cap about the installation:
"1) Install the Yellow Injectors
2) Install the Spacer
3) Check for Drivability.. and Look at Fuel Trims..
The 'Bench Mark' I used was a Long Term Fuel Trim of about -7.. it will range from about -5 to about -10.. If you are More Negative than -10 then you will need to raise the MAF.. if you are More Positive than -5 you will need to Lower the MAF..
All the MAF Mod does, is fool the ECU into thinking the engine is LESS loaded than it is.. so it will give MORE ignition advance.. The Side effect of this is the ECU will also give LESS Fuel.. So the two choices are Raise the Fuel Pressure or install bigger injectors.. I chose the Injectors as it simpler to do.. but either will work..
The Yellow Injectors were my first stopping point.. I set the MAF height to give a MID 12's AFR at WOT.. my STOCK set up was running in the 11's!.. My Next step was to go to the 'Brown' Injectors and Trim MAF Height to give 12's AFR at WOT and check drivability.. That never happened..
My 1ZZ is now Sporting a Crower Stage 1 Cam.. so any work I do will not be reflective of a Stock Machine.. The MAF Mod and the Stock ECU are playing nicely with the Stage One Cams.. The car scoots nicely now.. So I've stopped tweeking on it.. Also I've moved over to a 90's 300 ZX NA as my Daily Driver.. so the Spyder is not getting the miles it was..
With my STOCK engine I was getting Heat Soak Problems on +100F days on LONG drives pulling hills.. that is why I recommend bumping up the RON number.. California has 87RON!.. and I had to go to 91 to stop the Heat soak issues.. (91 is all we can get in the Peoples Republik of Kalifornia ) So I just run the 91 all the time as an insurance policy.. Winter I'll run 87 if it's not expected to get hot..
Learn what Engine Pre-Ignition/Knock sounds like.. If you hear it you have tuned it improperly..
I like to start out with Lo Octane fuel.. as I will hear the knock and it will let me know where on the Engine Load it happening.. then I can always Bump Up in Fuel to cover it.. "
cheers lamcote for this, I have read it before and found it very interesting.
What I make from my research is as follows:
Caps, -7 LTFT benchmark means the yellow 310cc injectors are over fuelling by default but the ECU is correcting this to reach stoichiometry. This is based on a 6.35mm spacer and removed vanes:
Raising the MAF reads more airflow and adds more fuel; thus retards ignition timing (using the suggested spacer profile) – (If you are More Negative than -10 then you will need to raise the MAF) – in this scenario the ECU in closed loop is reading too much fuel in the mixture, hence the LTFT of -10 or less
Lowering the MAF reads less airflow and adds less fuel; thus advances ignition timing (using the suggested spacer profile) - (if you are More Positive than -5 you will need to Lower the MAF) - in this scenario the ECU in closed loop is reading too less fuel in the mixture, hence the LTFT of -5 or more.
Only in open loop is the ECU referencing to its MAP's based on the input received from the MAF. And applies advanced timing and reducing fuelling by default. The lack of fuelling is adjusted by the huger capacity yellow injectors. But again in closed loop, the ECU has corrected for the richer condition as seen by the LTFT.
If I have the above working correct, then the potential danger zone of detonation is having the MAF too low as the timing is advanced and the AFR is running lean?
On another note, how do you read AFR? I can only access fuel trims.
You are the wrong way round with the raising and lowering.
Raising the MAF reads LESS airflow (and advances the timing) and lowering the MAF back down towards its normal position reads relatively more airflow until it gets back to normal. When you refer to lowering the MAF you are never actually lowering the MAF in real terms ie below its standard position, you're just not raising it as much. This means that, as long as you have fitted the yellow injectors there shouldn't be a detonation danger zone (unless you raise it way beyond the recommended 6.35mm when it might go all wrong) because you should only be running rich.
You need a wideband O2 sensor to read AFRs but you shouldn't need to do this if you are staying within Cap's suggested parameters. You just need the LTFTs. If the LTFT is less than +/- 10% (and STFT is close to 0) you know the ECU is happy with the resulting AFRs so you should be too. But you will need to run it long enough for the STFT to fall back to close to zero before you are happy of course.
Although we're not sure how it all works, we believe the closed loop LTFT is used by the ECU to modify the open loop maps so it all seems to work nicely in both closed and open loop.
An easy way to think about it is that if you just fitted yellow injectors and didn't touch the MAF you would obviously be running VERY rich, until the fuel trims catch up and get it back to stoichiometric, because you have simply fitted bigger injectors. You would therefore get a LTFT of maybe -ve 25? Because the ECU would be pulling fuel based on the O2 sensors rich readings in the STFT.
Raising the MAF will progressively reduce this LTFT negativity by reducing the over fueling created by the yellow injectors.
So you just need to raise the MAF until you reach the point when you are happy with the resulting LTFT. Although if you go much below Cap's -7 you will be in uncharted territory so beware!
thanks, that's a brilliant way of looking at!
Quote from: Optimus prime on August 21, 2018, 19:36
Ive found someone who will be able to machine a plastic spacer. Question is, how high should I make it? I will get a couple done so i'm happy to try a range of heights.
If you get this working will you be able to make some available to buy for the rest of us by any chance?
I will get this up and running first. I have 4 different sizes coming next week so I will have a play and keep you updated. how many people would be interested in a MAF riser?
I could be tempted at the right price, it's something I have often wondered about doing as an experiment.
Just a quick message to let you know I did the MAF raiser along with Yellow 2ZZ injectors and I'm over the moon with the results. The car has a sudden urgency when you squeeze the throttle. Much more responsive and more punch through the rev range. It just keeps on pulling, i've accidentally hit the rev limiter a couple of times because it just feels like it wants more! Don't get me wrong, it's no Turbo but it's a brilliant mod that I'm really happy that I tried it; No money was wasted here (unlike my induction kit attempt). Engine note has also changed, I can't wait to slap on a cobra or TTE exhaust in the next couple of months!
Excellent, what height did you raise the MAF in the end?
I raised it 1/4" (6.35mm). I also have a spacer 1mm above and below that benchmark. I will re-read the LTFT soon and make a judgement on whether it needs adjusting. From my initial trials it seems bang on!
I had the ID of the riser made at 31mm. If I were to do it again I think I would get a 31.5mm ID as 31mm is really tight on the o-ring around the MAF.
The engine note change is the timing adjustment the car makes. It's the first thing I noticed when I just put my map back on.
It's the poor man's piggyback ECU, the MAF mod. Clever stuff
Quote from: Optimus prime on September 4, 2018, 07:24
I raised it 1/4" (6.35mm). I also have a spacer 1mm above and below that benchmark. I will re-read the LTFT soon and make a judgement on whether it needs adjusting. From my initial trials it seems bang on!
I had the ID of the riser made at 31mm. If I were to do it again I think I would get a 31.5mm ID as 31mm is really tight on the o-ring around the MAF.
Is it a simple plastic ring? Where did you get it made, can I ask how much it cost? Cheers
I had mine made out of aluminium as it was easier for the guys to manufacturer but either plastic or metal are suitable.
I got mine done through a friend at a super buddy hug price of nothing.
It was done by a machining company with a CNC machine. I gave the ID, OD and thickness. That's all they needed and the result were perfect.
The company I used were EyeTech engineering but I would guess with a little google searching in your area you would find someone nearby. If you get stuck do give me a shout.
What OD is required? Otherwise it's 6.35mm thick and 31.5mm ID? No notch required for the MAF?
I went with a 37mm OD which was fine.
I didn't do a notch for the MAF as the ID of 31.5mm would clear the MAF sensor. unscrew your MAF and have a look at it, i really don't understand how/why people made notch's in theirs.
Excellent, thanks.
hey guys,
Quick update; I raised the MAF to 7.35mm and I lost the power I had before and the ECU was pulling more fuel (LTFT seen on attachment). I returned it back to 6.35mm and the power came back. I will do some more readings once the LTFT have levelled out, once I have those readings I will lower the height to 5.35mm and check the results.
I just wanted to highlight this as only 1mm had a big impact on performance
Very interesting to see the results with the higher and lower MAF settings
Nicely done
Good result! What fuel were you running on to see the improvements? Or to put it an other way do you need to use premium fuel?
I can safely use standard fuel in the UK but to my knowledge this wouldn't change LTFR's
Using 6.35mm spacer...
Fuel trims are reduced so the ECU is pulling less fuel but i think i might have a leak in fuel or air as the banks are reporting different results... see the scale of the fuel trims on the bottom right and left
Anyone have one of these to hand? thinking this is an ideal candidate for 3d printing
As the proud owner of a 3D printer I would be able to make them to any height required in steps of about 0.1mm
3D printing would definitely get you there. I installed the 5.35mm spacer today and it doesn't pull as hard as the 6.35mm spacer higher up the rev range. i'm just waiting on the LTFR's to settle before i post another result.
Hi Guys,
quick summary of my findings.
With the yellow injectors in, the vanes removed and the MAF raised different levels I found the following:
5.35 spacer: ECU pulled less fuel on the LTFT - Throttle response was good but power over 5000 RPM was lacking compared to the 6.35 spacer
6.35 spacer ('official' recommendation): - Throttle response is great and pulls a lot harder from 3000 RPM to redline (much improved over stock)
7.35 spacer: ECU pulled more fuel on the LTRT - Throttle response was poor (similar to stock) and the power was not comparable to either of the above.
My theory based on research of the Mod is; with the 5.35mm spacer timing is advanced but it's over fuelling at the top end causing it to 'slow down'. 7.35mm spacer has less advance and becomes more like stock. What i'm amazed at is that only 1mm has a huge impact on performance. What i have done here is nothing new but I found it interesting, it just puts my mind to rest that 6.35mm spacing is spot on.
the reasoning for trying the different spacers is because i removed the restrictive bend from the side hose to the air box and i wondered if this would have an impact on the MAF mod and the spacing... apparently not.
I'm so glad i did this mod, forget about figures and dyno's etc. it makes the car faster and more responsive, £60 well spent!