Caps Maf Riser Mod

[shnazzle]

Remember o2 sensors are slow though. It's not a wideband. And especially in open loop (cold startup for quite a while, overrun, full throttle) the ecu goes off the fuel map and long term trims. 

You're relying on the car's compensation tables and rpm goals to clean that up. 

The general consensus on the MAF mod is that it works well EXACTLY under the parameters Cap created. Any deviation (change in intake, change in fueling, etc) and you're on your own.

Regardless, the car is expecting much smaller cc injectors. So you're forcing it to compensate constantly.

[Petrus]

Remember o2 sensors are slow though. It's not a wideband. And especially in open loop (cold startup for quite a while, overrun, full throttle) the ecu goes off the fuel map and long term trims.

You're relying on the car's compensation tables and rpm goals to clean that up.

The general consensus on the MAF mod is that it works well EXACTLY under the parameters Cap created. Any deviation (change in intake, change in fueling, etc) and you're on your own.

Regardless, the car is expecting much smaller cc injectors. So you're forcing it to compensate constantly.

enter the sensitivity, or lack thereof, of the O2 sensors.

To be complete; it álso expects less air then is actually flowing.

Concerning the intake mods, that reads ´standard filter housing and down stream´. A different intake elbow or sports filter does not upset the formula. In other words a Markiii pipe and K&N element will do fine.

For me there are two contradicting aspects:
1. I really do not like the ´fooling´ of the ecu
2. I really like more ignition advance

To achieve the second the alternative would be an extra box of tricks álso manipulating the ecu but at a far greater cost.
Also the set came at the right moment; was going to pull the valve cover off this week and now make that when the set is in. Yes, I know, no need but it does make swapping injectors less fiddly.

The bottom line of the MAF mod. is just about thé best tuning return on investment for the n.a. 1ZZ. Fingers crossed the sensors are up to it. If not; it´s reversable.

[shnazzle]

The part I don't like (and why I no longer run my piggyback) is that the 1zz is a knock-prone engine.
Timing is already set to provide maximum torque with a margin of error to accommodate different air density to increase engine life. 
To me, the MAF mod just eats into that margin.
You may see a bit of torque gains. Not an issue, as long as you make sure you're always operating that vehicle within that margin. If for whatever reason the mix ends up lean while you're hoofing it... Bad times.

But that's the "tuning" game isn't it?  

Good fun. Only live once. 

As for alternative; bit more expensive but arguably less "dirty" is a piggyback. You can do one of two things; manually change timing advance on a map, which allows you to be a lot more controlled over where you apply the advance, as opposed to everywhere. Or change the airflow output. Which essentially is exactly the same as moving the MAF. But again, more control over the calibration. That often automatically adjusts timing. Then you can add fuel to compensate via the fueling adjustments. 
That's why I sold my MAF mod kit. 

Downside of the piggyback... Maf calibration. Get it wrong and it's all over the damn place.

[Call the midlife!]

Which reminds me, I really should sell the yellow injectors and Emanage I never bothered fitting...🤓

[Petrus]

Downside of the piggyback... Maf calibration. Get it wrong and it's all over the damn place.

...and why you ditched it.

We are on the same wavelength. Hence my dislike of fooling the ecu.

I also agree that the longstroke ís more knock sensitive BUT we should bear in mind that the thing is programmed for the USA 89 rated fuel, which over here is 93 rated.

For those baffled by ratings: They are index numbers comparing to 100% octane. That is why aviation/racing fuels can rate over 100.
The different ratings for the same fuel stem from different test conditions: A different standard motor, different operating condition gives a different rating.
The RON number is higher than the MON number.
Over here the RON number is given because it looks better.
In the USA it is the average of RON and MON.

Back to the 1ZZ; that is safe for RON 93.
Cap Weir noticed that the MAF mod could do with a bit more safety margin on long climbs on a hot day so to be sure advised 91, our 95.
Mind, that is with the OEM catalist. On a sports or no catalist, the engine already runs cooler.

Lastly, in the States there is no freely availeble equivalent of our 98.

So, even though 95 should be cool, we have the better flowing exhaust ánd 98 as XXSafe.

Just as a perspective; the closest 98 pump is at 4 km and at the highway exit/entry from the village. Just befóre the pump station, we have an airport for small aircraft and ... that has Avgaz from the barrel :-)
No, seriously, E5 Euro95 is quite sufficient and I have that at 1 km.

Which reminds me, I really should sell the yellow injectors and Emanage I never bothered fitting...🤓

[Petrus]

Which reminds me, I really should sell the yellow injectors and Emanage I never bothered fitting...🤓

Wait, we now have a spare spacer ánd a set of yellows!! Gogogo boys (m/v).

[Beachbum957]

Those of you running this mod, what effect does it have on fuel consumption?

And if anyone reading this wants the maf spacer, I have a spare.

We were one of the early adopters of the MAF mod using a spacer directly from Cap and have been running it for almost 7 years and thousands of miles.  We picked up 1-2 MPG in most conditions.  We installed the mod on another MR2 and got the same results.  Both are using a cheap Chinese clone header, which work well enough.

I suspect the increase is as much from needing less throttle because of the improved midrange torque than it is from any timing changes. 

The only downside was the somewhat abrupt fuel cut when off throttle at about 3,000 RPM.  Oddly enough only one MR2 had the problem.

[Petrus]

We were one of the early adopters of the MAF mod using a spacer directly from Cap

You sure were!
Cap made only a few and asked Corky to take over.

Thanks for sharing the long time first hand experience. You setting it over to the next speaks volumes.

[Beachbum957]

We were one of the early adopters of the MAF mod using a spacer directly from Cap

You sure were!
Cap made only a few and asked Corky to take over.

Thanks for sharing the long time first hand experience. You setting it over to the next speaks volumes.

The second MR2 used a spacer from Corky, but the results were the same.

[Petrus]

From what I understand Corky added a seat for the O-ring in later runs to make it more fool proof.
The MAF can be fitted without the o-ring using a light smear of sealant but without the seating the O-ring makes the MAF sit too high. This led to considerable confusion.

[jvanzyl]

Has it arrived yet Petrus??

[Petrus]

Has it arrived yet Petrus??

Don´t know.
Am at Málaga Girl´s.
Will see Monday but regardless not getting on with it till later in the week.

[Petrus]

The mod kit arrived in the mountains!!
No rubbahs yet.

Next weel the weather forecast is bright so should get round to it then.

Back to the kit: The spacer surprises me a bit being in alumminium with o-ring in groove; nice! Had expected plastic.

[Petrus]

Still on the agenda.
New o-rings and donuts fitted on the injectors.
The cam cover gasket has turned up but now Í am off for a few days. Grrrr...
Next week. I hope.

[The Other Stu]

I have all the gear and no idea 
I remember someone said something about it being a messy job taking out the injectors as you're likely to get fuel everywhere.

Anyone have a good way of replacing the injectors?

I bought one of the 3D printed risers.

[jvanzyl]

I have all the gear and no idea 
I remember someone said something about it being a messy job taking out the injectors as you're likely to get fuel everywhere.

Anyone have a good way of replacing the injectors?

I bought one of the 3D printed risers.

Just need a tiny bit of grease (red or silicone) to ease the injectors back into the fuel rail.
I used a combination of my phone and a mirror to see over the corner so I could slot them back in.

If you want  - we can do both of ours together one evening? Doesn't honestly take that long, just haven't been motivated lately.

[Carolyn]

I have all the gear and no idea 
I remember someone said something about it being a messy job taking out the injectors as you're likely to get fuel everywhere.

Anyone have a good way of replacing the injectors?

I bought one of the 3D printed risers.

Just need a tiny bit of grease (red or silicone) to ease the injectors back into the fuel rail.
I used a combination of my phone and a mirror to see over the corner so I could slot them back in.

If you want  - we can do both of ours together one evening? Doesn't honestly take that long, just haven't been motivated lately.

A smear of engine oil works really well.

[Call the midlife!]

I have all the gear and no idea 
I remember someone said something about it being a messy job taking out the injectors as you're likely to get fuel everywhere.

Anyone have a good way of replacing the injectors?

I bought one of the 3D printed risers.

Cold engine, disconnect the battery and it doesn't really matter if you lose some fuel, it'll clean things up as it sprays around and then evaporate 😂.

If you lay a couple of rags over the fuel rail it'll stop any spraying too far.

[Petrus]

I will be taking off the cam cover so can actually see what I´m doing.

It is sweating to the spark plugs anyway ánd I´like to do away with the plastc vanity thing meaning a vanity polish of the aluminium.

[jvanzyl]

I will be taking off the cam cover so can actually see what I´m doing.

It is sweating to the spark plugs anyway ánd I´like to do away with the plastc vanity thing meaning a vanity polish of the aluminium.

knowing what I know now in terms of how easy it is to remove - this is absolutely the easiest way of doing things. More time consuming possibly - but infinitely easier.

[Carolyn]

I will be taking off the cam cover so can actually see what I´m doing.

It is sweating to the spark plugs anyway ánd I´like to do away with the plastc vanity thing meaning a vanity polish of the aluminium.

knowing what I know now in terms of how easy it is to remove - this is absolutely the easiest way of doing things. More time consuming possibly - but infinitely easier.

That plastic 'vanity thing' keeps rain water from gathering in the spark-plug holes.

[shnazzle]

I will be taking off the cam cover so can actually see what I´m doing.

It is sweating to the spark plugs anyway ánd I´like to do away with the plastc vanity thing meaning a vanity polish of the aluminium.

knowing what I know now in terms of how easy it is to remove - this is absolutely the easiest way of doing things. More time consuming possibly - but infinitely easier.

That plastic 'vanity thing' keeps rain water from gathering in the spark-plug holes.

And we've seen a number of coilpack failures over the years. Particularly from 2zz conversion who leave off the "vanity cover".

[jvanzyl]

Does it rain in Malaga?

[Carolyn]

Does it rain in Malaga?

Not much - but he might wash the car quite frequently 'cos of the dust?

[househead]

Does it rain in Malaga?

I wondered the same about Alicante before visiting there last Sept. Rain is not the word, it was like being stood in a waterfall for 3 days. If it were not for the 4th day being dry, I think we'd have jumped on an early plane home! The South got it bad at the same time, @Petrus posted some pics and commentary. Worst weather they've had in decades apparently. Holiday was a success but it was in the balance!