Caps Maf Riser Mod

Started by shiny, August 29, 2014, 18:10

0 Members and 1 Guest are viewing this topic.

shnazzle

Quote from: Petrus on April 26, 2020, 10:49Thanks Patrick.

The crux I was looking for being that the tables are 30-35% ´wide´ anyway.
So one cán flow 30-35% more air, the ECU will not throuw an error, the Yellow injectors squirt too much and the O2 signal makes the ECU turn down the whick in effect matching the air flow.
Shouldn't need to. Aside from the fact that you're never ever going to flow even 10% more air on normally aspirated, let alone 30-35. No matter what intake trickery you use. There's at atmospheric theoretical maximum on any given day for the conditions without boost (and excluding ram effect from pulses) that's the most you're going to get. The ecu's table will happily work with that range without needing fuel trims.

IF and only if you stay with the rough AFR the ecu expects. If you can keep the o2 sensors happy, it'll never need trims. 

Fuel trims (short and long) are only there to account for aging components, inefficiencies, atmospheric differences. They're compensation metrics.
Also bear in mind that relying on them is dangerous because your car spends a fair bit of time in open loop where your fuel trims are not there to "save" you
...neutiquam erro.

Petrus

Quote from: shnazzle on April 26, 2020, 11:42Aside from the fact that you're never ever going to flow even 10% more air on normally aspirated,

Euh... yeah you do.
Remember that the engine is an air pump. The burning of fuel is only the internal drive of the pump.
From chain of the fow included the side inlets in the quarter panel to the very tip of the exhaust.
Fit a tubular manifold, sports or decat and a sports muffler and the inlet will by default flow at léast 10% more and the restriction will be somewhere else.
Tackling thát will in the end lead to the head/stroke being the restriction. From what I gather, that will be at about 20% more air than OEM.

Its-a-simple Patrick. Without more flow of air, there is no increase in output.
The measure max Dyno output without flowing the head/new cams is some 170-175hp. Even if you take into account that this may be optimisic readings, you still get at a potential of 20% more output = more air flow.
If I remember correctly you yourself measured at least 10% extra fuel flow as a result of deristricting the exhaust. This equals at least 10% more air.

Mind, it is all marginal in the light of forced induction. That is obvious.
That does not make 10 to 20% more flow of air impossible though.

A thing to mull over: Fit a scoop to the side inlet and there wíll be!!! more flow though the pump.

shnazzle

10% was just a flippant guesstimate and I did mean from just intake changes.

Hence why my post in the Final word on intakes finishes by saying that all the gains are in the exhaust.
Unless you start putting in higher lift cams etc etc. 

But, there is nothing you can do to the intake, in my opinion, that will make it flow more. It might flow differently, unleashing a more immediate throttle or more low down torque at the cost of high end, or vice versa. But not more. Because on our cars it is limited by what happens after the throttle body. 

With or without MAF mod. 

What WOULD be good is if someone did a MAF mod #2,but with a high flow filter. That way getting the advance, the immediacy on the throttle and the nice roar :) 
It's very much possible. Just needs the same tweaking and experimentation that Cap did originally. But it would only apply to that one specific intake. 
So you'd end up 
MAF Mod Original
MAF Mod PPE
MAF Mod Hurricane
MAF Mod K&N 57i
And each one may have different injectors, different MAF spacer, different vein setup. 

I'd love to have I built for my Hurricane so that I could put it back on without all of the negative effects.
...neutiquam erro.

Petrus

Quote from: shnazzle on April 26, 2020, 14:0410% was just a flippant guesstimate and I did mean from just intake changes.

Ok, missed that. Would agree with that. Without deristricting the exhaust tehre is no way more gets in unless you púsh it in.

QuoteHence why my post in the Final word on intakes finishes by saying that all the gains are in the exhaust.[
Unless you start putting in higher lift cams etc etc.

But, there is nothing you can do to the intake, in my opinion, that will make it flow more. It might flow differently, unleashing a more immediate throttle or more low down torque at the cost of high end, or vice versa.

Well....
Improving the exhaust makes the inlet flow more, making the whole, each and every element, more restrictive.
Toyota designed it to flow as much as the exhaust passes.
With the TRD horn they already point out that there ís room for improvement.

QuoteBut not more. Because on our cars it is limited by what happens after the throttle body.


Seems that this ideed is the limiting factor once the system is flowing 20-25% more.


QuoteWith or without MAF mod.

What WOULD be good is if someone did a MAF mod #2,but with a high flow filter. That way getting the advance, the immediacy on the throttle and the nice roar :)
It's very much possible. Just needs the same tweaking and experimentation that Cap did originally. But it would only apply to that one specific intake.
So you'd end up
MAF Mod Original
MAF Mod PPE
MAF Mod Hurricane
MAF Mod K&N 57i
And each one may have different injectors, different MAF spacer, different vein setup.

I'd love to have I built for my Hurricane so that I could put it back on without all of the negative effects.

I will stick with Cap´s MAF mod, TwinAir, deduct and now improved intake horn.


DanRS4x

Is this a suitable place to ask a few questions about this please? I've read the thread in Spyderchat and a few others, but I can't remember if these answers came up.

The first is which insurers are ok with the MAF mod? Direct line who didn't blink over lowering and custom exhaust wouldn't touch it, because it was an engine mod.

The second is can someone recommend where to get the spacer and injectors?

The recommendation is to use super unleaded which is 98 ron?
Oscar (the Grouch) named for the grumbly exhaust note
2005 silver HT/AC, Stainless Creations twin exhaust, Tein lowering springs, Ultra Racing front strut brace, Dev's door bushings (more mods to come)

Gaz mr-s


FromTheDarkness

Who and where do I find the sellers of the "kit" or can someone offer alternative( 3d printed etc) spacer, then I can source the rest of the bits.

Gaz mr-s

There aren't any 'sellers' as such. You just need to keep your eyes peeled on here or on facebook groups for the bits.  ChrisW that I got my spacer from was prompted by someone else & made a small number with the proceeds going to a charity.  Whether he might make more....but not right now due to Covid.

Petrus

#108
A same day comparison, nicked the graph from Spyderchat, blue is MAF mod.
I call that quite a result for such minor trickery.


AdamR28

Wowzers... but, does look like the sort of improvement you get from advancing timing a few degrees.

Do you have a link to the thread Petrus?

Petrus

Quote from: AdamR28 on October 31, 2020, 08:23Wowzers... but, does look like the sort of improvement you get from advancing timing a few degrees.

Do you have a link to the thread Petrus?

There is no info in it. Thís thread is umpteen times more usefull.

Beachbum957

A friend did the same dyno test with and without the MAF mod.  Both tests were with a Zero header and a low mileage shortblock.  The dyno charts were similar to the one from Petrus, but he saw a 5 HP increase, possibly because of the header.  The dyno runs were repeated multiple times with the same results.

The same person then added Crower Stage 1 cams and a flow benched head with a port cleanup.  The cams didn't work well with the MAF mod and stock ECM, but after experimentation w/o the mod, the dyno showed a 1 HP gain over the MAF mod and stock engine but with slightly lower peak torque.

His MR2 with the cams and our stock MR2 with MAF mod feel almost the same when driven back to back.  If anything, the car with the MAF mod had slightly better throttle response.  Both cars have almost identical fuel trims

The MAF mode is a very cheap way to get more performance.  We have been running it for over 7 years with zero issues

Petrus

Quote from: Beachbum957 on October 31, 2020, 12:04A friend did the same dyno test with and without the MAF mod.  Both tests were with a Zero header and a low mileage shortblock.  The dyno charts were similar to the one from Petrus, but he saw a 5 HP increase, possibly because of the header.

Probably the header as the chart I copied also gives a 5hp gain, only at different revs, zero at the top end where the stock exhaust is most likely the bottle neck.

Petrus

#113
With excuses for resurrecting an old thread; would like to update and this is the imo best place.

For the air flow, the bréathing, Patrick was bang on the nail with the observation that all is governed by atmospheric air pressure.
The air flows into a hole, in this case the intake, from the outside only to compensate for a lower pressure inside the hole/intake.
Any restriction exhaust side means less scavenging means more residual pressure, means more suking needed by the piston going down to lower the pressure inside the hole.
On the intake side we have pretty much the same: Any restriction means more drop in pressure needed.

Now there are two main restrictions designed into the ZZW30 air pump. Both to reduce the noise. One is a serious restriction in the flex connection of the OEM cat. The other is a serious restriction in the entry horn/elbow on the air filter box.

I have done plenty of ceteris paribus as possible before and after comparisonswith several intake and exhaust mods.
It makes no sense modding the intake unless the OEM cat flexi is de-restricted.

As Patrick, again, boringly spot on, has explained it has no effect on what the MAF does. That stays the same.

Back to mine.
I am running a TRD type deducted / derestricted entry to the air box.
Like TRD a sports filter.
Generic decat unequal length decat exhaust manifold.
A decat pipe.

It now breathes as freely as it comes which means a higher filling rate meaning a higher mean piston pressure meaning more powah but also more need for higher octane fuel because of the MAF mod ignition advance.

Bottom line is that it makes for quíte a difference.
Not done nor doing a dyno run but the data from the accelerometer (compensating for the lightness added) it has well over 10% hp more than stock.

The starting remains the same again as Patrick explained, pfffff...., depending on whether conditions being as the ECU remembers them.
Brisk when cold (and more or less the same as before).
Brisk when hot.
Brisk to reluctant in between.

Bottom line: A3VT!

or in good old English GO FOR IT!

Gibla

Quote from: Petrus on April 13, 2023, 21:56it has well over 10% hp more than stock

That's mighty impressive

yellow injectors, MAF mod ,new O2 sensor now en-route
 
2001 Dark Green MR-S (6R4)

Petrus

Quote from: Gibla on April 13, 2023, 22:33That's mighty impressive

yellow injectors, MAF mod ,new O2 sensor now en-route
 

Mind that is with the whole flow optimised. The MAF mod ´just´ shifts the ignition table to a different octane rating. Improving flow makes more use of that.

Gibla

Quote from: Gaz mr-s on June 29, 2020, 00:52There aren't any 'sellers' as such. You just need to keep your eyes peeled on here or on facebook groups for the bits.  ChrisW that I got my spacer from was prompted by someone else & made a small number with the proceeds going to a charity.  Whether he might make more....but not right now due to Covid.

Hi @Gaz mr-s , nearly 3 yrs on since you gave that reply .....would this ebay item look anything like the original concept?
https://www.ebay.co.uk/itm/264943533139
2001 Dark Green MR-S (6R4)

J88TEO

I am using the one on eBay.

Petrus

Quote from: Gibla on April 14, 2023, 07:25Hi @Gaz mr-s , nearly 3 yrs on since you gave that reply .....would this ebay item look anything like the original concept?
https://www.ebay.co.uk/itm/264943533139

Cool  8)

Kuddos to 3D printing!

Gaz mr-s

Quote from: Gibla on April 14, 2023, 07:25Hi @Gaz mr-s , nearly 3 yrs on since you gave that reply .....would this ebay item look anything like the original concept?
https://www.ebay.co.uk/itm/264943533139

Yeah. The price is a bit steep though. But if J88TEO thinks it works well, that's the main thing. They have to be accurately made I believe.

J88TEO


Beachbum957

We have the MAF mod on 2 different MR2, and it definitely works.  The torque increase at lower RPM is very useful. 

A word of warning.  Some have tried the mod with cold air intakes, and most have found it doesn't work well with any CAI.  The concept was created with a stock intake system, and any major change doesn't seem to match well.

Stick to the original concept, and it is a relatively cheap performance boost with no downsides

kiril89

Will be looking at getting this done in December. Any recommendation where to get the injectors? Thanks!

bluesmoke

I have bought a 3D printer riser off of ebay and am about ready to fit but have a couple of questions;

The 2zz injectors, I saw someone say you use 1zz seals on them, but surely the ends being different means that's not possible?

These 3D printed risers have no provision for O-rings anywhere, should I use a touch of selant either between the maf tube and the riser or between the riser and the maf?

Many thanks!

Carolyn

When I used the yellow injectors I'm sure I used the same O rings and bottom seals as for the green ones.
Perry Byrnes Memorial Award 2016, 2018.  Love this club. 
https://www.mr2roc.org/forum/index.php?topic=63866.0

Tags: