TheAllusionist

This is probably a dumb question, but you can just call me "Dummy" if you have a good answer!

I am trying to keep my 1986 951 as stock looking as possible and parts I put on ones that where available options (more or less) due to the low mileage of my car. I am just getting into the performance tweaking so excuse any stupidity on my part.

My question is: Can you modify the stock AFM to accommodate more than 320 HP? Are there shops that port and polish for example, or make mods so that the car looks original but breaths better?

I know there are many parts to the equation, I plan on getting a K26/8 and having it rebuilt with modern parts, I am told that could top out at around 350 RWHP, if all things are right. I have been stock piling performance parts: 3 bar adjustable pressure reg, 55# Fuel Injectors, LR dual port wastegate, manual boost controller, boost and a/f meters.... I plan on looking into modified intercooler and A-Tune, but perhaps that is all overkill for this application.

In the end I just want to have my car appear stock but get the most performance out as I can while respecting the low mileage vehicle, with all that said from reading the forums it sounds like the stock AFM will probably be the limiting factor and I don't want some big MAF setup under the hood and as far as I know Vittesse is the only one making a stealth one and that seems like more modifications than I want to do on this car. I just thought maybe there were performance modifications that could be made to the stock AFM and wanted to know what they are and who does them? Thanks for your time.

kevincnc

It's kind of funny that I saw your post since only glance here every few months these days. Here you go-
https://rennlist.com/forums/944-turb...-pictures.html
You can just buy my car and get it over with..
Kevin

TheAllusionist

Thanks for the link, you have done some very nice modifications and upkeep on your car, I would love to buy your car, but doubt I could afford it!

So you bought a stealth from Vittesse Racing and modified it to your air box, I know he sells the stealth, but not a lot of good pictures on his site and hard to find it and pricing on his site on the stealth MAF.

I was hoping there were mods/enhancements that could be made to the stock one, but probably not. Thanks again for commenting and sharing the link to your amazing work, I lucked out timing wise it seams! Hey, what does the outside of your car look like, I know your engine compartment is spotless!

TheAllusionist

Oh, I saw the outside, gray, very nice!

azbanks

There are vendors that sell chip upgrades for the stock AFM. With some of them you do need to upgrade to a 3 bar fuel pressure regulator but everything will look stock. You can add a manual/adjustable boost controller but you would not have to.
I have a Vitesse AFM chip that I am trying to sell. $200 shipped.

Dougs951S

You can port out the AFM and it will flow a bit more, just be sure not to mess with the area where the flapper seats. I have a ported 86' AFM but I think the resistor strip is done, I have no idea how much more than a stock AFM it flowed, I switched to stand alone shortly after porting it so I don't really know if it was worth my time truthfully.

TheAllusionist

Thanks, I plan on doing an A-Tune, I am just looking for all the things I can do to stock system and was curious about performance upgrades to the AFM.

Thanks for the information, exactly the type of information I was looking for, too bad you don't know if it flowed or performed better. Since I haven't taken apart and AFM yet, I don't know if the reistor strip is a replaceable part, if it was I would be curious if you were interested in selling your modified unit? Thanks again for the information, could be I buy a used one and take it to a performance machine shop that ports and polished heads, etc..

Paulyy

I see it as more of a inconvenience IMO. If you try get your AFM to flow more air, that means the voltage vs CFM will change. That means you'll need a different tune, nothing off the shelf will help as they only with with the standard AFM.

Zuba951

Here is some information on the air-flow meter. This is from Bosch Gasoline Fuel-Injection Systems L-Jetronic and Bosch Fuel Injection & Engine Management

TheAllusionist

Thanks for that bit of information, exactly why I am asking, always good to hear the Cons as well as the Pros/Means and Methods. I appreciate everyone sharing their knowledge.

Paulyy

IMO, if you want to keep it stock, go get the Rogue Tuning A tune or the vitesse tune. you'll be happy with it.

TheAllusionist

I am planning on getting an A-Tune, just trying to figure out all the mods so when I get it, it is optimized for my build and that it is the final build for this car, trying to be smart about it, but also have no regrets for what I should have done.

Paulyy

Easy.

- 3 bar FPR
- Dual port wastegate. Tial 38mm and fejjj has adaptors ( https://rennlist.com/forums/944-turb...-adapters.html )

remove the cat or high flow cat if you wish, always frees up power.

TheAllusionist

I have a Lindsey Racing Adjustable 3 bar FPR, LR Dual Port wastegate/Manual controller/gages, LR 4" exaust and 55# Fuel Injectors, all waiting to be installed when I get it all together. Working on getting a K26/8 to have rebuilt with the latest greatest, the A-Tune and perhaps a modified intercooler. I am working on having it breath as well as possible and that is why I was asking about modifying the AFM.

Just patiently acquiring the parts so I can put it together at once, after this work I will focus on the suspension and braking, or could be I do that first if I see a good deal. I realize suspension and braking are probably more important that the engine performance, but that is a whole other topic all together.....

TheAllusionist

P.S. thanks for the link and pointers!