ok i have an 1999 formula and my mods are lt headers slp 85maf and ported t/b,ls6 manifold,3.73,vinci handheld programmer,free mods,msd wires,ngk copper plugs,volant cold air intake,slp bellow,...ok so now my question is that when i drive my car it feels sluggish so do u think it cold be that i need to mess with the programmer some more or could it be the slp85mm maf causing me too run too lean.

 

get rid of the maf sensor from slp.. had it.. sold it... ran better

 

With all the air induction mods I'd say you're lean . . . .

 

ok so what should i do that could really help my car out at this point..

 

ditch the 85mm maf sensor.

 

ok thanks alot..

 

The SLP unit will make you run lean. The resistor that SLP uses in their MAF only falls within 20% accurate If I remember correctly. I would have spec'ed out a 1% tolarance. I just desoldered the resistor and used a known truck MAF table through LS1 edit.

 

ok so im my issue i should get rid of the 85mm and give it more fuel..

 

Best way to know whats going on is hit a dyno and get an a/f session, that way you can see what your a/f is thorugh the curve, Also very helpful is a datalogger so you can read your 02's and timing while cruising. Sounds like what you need is a dynotune.

 

This is a copy/paste from the Vinci programer tunning page..
· While our tuner works with and enhances many other performance components and modifications, it will not work with high-flow mass airflow sensors. This is because high flow mass air flow sensors require a change to all of the air flow tables in the computer and these numbers change significantly with the different type of MAF sensors on the market. Stock LS1 MAFs will support in excess of 500hp with a supercharger.

 

My SLP MAF is making my car run PIG rich.

 

my car has been running really rich and i think it might be my maf. my ses light is on for a short in my o2 and it had a pending code for my maf. so after reading all that you guys have said i believe it might be the reason i am running so rich. my question is that if i have to replace it anyways should i go with a stock one or a aftermarket one? a friend of mine who drag races told me to get a Granatelli maf instead of a stock one. he knows stuff about racing but not about ls1s so i thought i would ask you guys. what i want to know is will there be any advantage over the stock maf? i have read that also about stock ones being good up to 500hp but i just wanted to make sure before i go spending money. i work at Advance Auto Parts on the weekends and i can get the stock one with 20% off so i would prefere to go that route but i don't mind paying for performance if it's worth it. thanks guys and sorry i crashed you thread ls1birdman but i saw no reason to make another one when you guys were done. thanks again......zac

 

Ported MAF's will make you run lean, because unmetered air is passing through. The SLP 85mm MAF, however, is designed larger as an entire unit, and it meters all the air that passes through. Until you are retuned, that increase in air flow will make your car dump fuel to compensate.

 

So your saying it is a wise idea to have your car dynotuned after installing a SLP MAF or any MAF. I installed mine last year, and honestly, didnt notice much of anything other than the car drinkng maybe a lil more gas than usual.

 

It's very important to have it tuned. Those MAF's are known to make it run lean at WOT, which could cause you big problems.

 

how bout a answer for my question? /\ .i really don't need to know right now cause i'm gonna have to rebuild my tranny first but i would like to know so i can start getting prices up. thanks again guys.........zac

 

Stock!

 

Do not get a granatelli.

The stock MAF is fine for all applications up to around 500hp. There is also no need for a 85mm MAF unless you are running 90mm TB and lid. Think about it - on a stock setup with 85mm maf your air is going through a 78mm lid, through a 85mm MAF and back into a 78mm TB? Makes no sense.

 

thanks guys. that doesn't make any sense when you put it like that. i do have another question though. is there any diffrence between a lt1 maf and a ls1. the part numbers are the same for both applications but i thought there would be a diffrence. thanks for the help..........zac