I have a 02 SS with stage 3 heads and cam for Patriot. I have 36lb injectors. It obviously has ram air. It has SLP airbox, and exhaust. It has longtubes and no cats. Livernois has tried to tune it 4 times. it is the best it has been now, but I think it is still really rich ezpecially at idle. Livernois offered to sell me Granetelli MAF 85mm and BBK 80mm throttle body. These are going to run me $650-700. I need advice on less expensive TB 1st. Then I also need to know if I need bigger rubber tubing also?

 

and what makes you think the maf and TB will help your tune??

isn't it kindda the nature of the beast (heads and big cam) to run rich at idle??

 

To be honest I do not know too much about this kind of thing. I am just a mortgage officer with a car I want to go fast.
Dan Millen at Livernois (the person who tuned my car) suggested this may be the way to go b/c he was having a tough time getting enough air into the motor.

 

there are plenty of 400+ hp cars running stock (or ported) mafs and throttle bodies.

i'm running ported maf ends and a ported tb...and i'm at 400hp on stock heads

 

oops....wrong thread

sorry

 

what are the pictures of?

 

Hey teke, What did you use to port out your TB and MAF? Do you have any pics?

 

i used my dad's machine shop to port the TB. just threw it on the lathe and bored it out a few thousands at a time. pics of that are on my website, page 2 near the bottom.

the maf was a composite maf end that i picked up about 5yrs ago from GMS. check out Jegs or Summit for them. although it really isn't needed, stock maf is fine.

i bought it before i knew any better.

 

If you want a car that goes fast who cares if it's rich at idle? Most cars run more towards the rich side at idle, and every car with LT's/ORY I've ever stood behind smells like raw fuel at idle. Why did you have the car tuned 4 times? Did the set up of the car change? Or are you just trying to have it not run rich at idle? With stage 3 heads and a cammed car, you're probably not going to have a real clean idle, if you've got a cam that's matched to those heads and shooting for max power. Give us a little more info (cam specs) like why the tuner can't get enough air to the motor at idle. What's your A/F? Is it just idle that is running rich or are you running rich at WOT also?

Abe

 

It really depends on how the tuner played with the PCM. Many tuners used to "scale" the injector flow rate table to control fuel delivery. Now, people are tuning via the volumetric efficiency table because it's the airflow that is the variable...not the injector size. However, even if you scale the injector size to get your desired AFR, the car still learns using feedback from the O2 sensors. Unless you're getting an SES light from excessive negative fuel trims, you're not running too rich at idle. The computer will pull fuel to maintain a stoich AFR of 14.7. If it's pulling (or adding for lean conditions) more than 25%, it will trigger an SES. What evidence do you have that shows your car is running rich?

 

I know it is running rich for 3 reasons. i hesitate to say it is rich ONLY at idle b/c...I do have SES light on. It used to flash, but now it is just on all the time. Also, I have black **** coming out of the exhaust and so much so it is on my garage floor. Also, the tuner advised he had a tough time getting enough air to the motor.
I had to get it tuned 4x b/c I was ALWAYS either having the car stall and SES light on or way to high of idle and made it difficult to stop b/c it would actually speed up if i took my foot off the peddle at 30mph!
The cam is .585/.585 - 276, 226@50/226@50, heads stage 3 62cc 2.05/1.60CNC. Again, the mechanic also recommended the 36lb injector so I bought it. IS IT POSSIBLE THAT THE CAR IS GETTING JUST TOO MUCH GAS INSTEAD OF NOT ENOUGH AIR?

 

by the way, I have no idea about the A/F ratio. I paid the tuner to fix that. Sorry

 

a 226 cam is a relatively mild cam. there are plenty of people running 23x cams on stock TB and maf. i don't think it's a problem with lack of air.

sounds to me like your tuner doesn't know what he's doing. or else you have other problems that are tripping the SES and causing the stalling

 

What he said...


I'm guessing you have a pretty good stall too? Usually, a flashing SES light is an indicator of a misfire detection. But, because of the way the PCM calculates misfires, a higher stall can trick the PCM. Teke's right. 226 cams should be cake for a tuner. People who tune their own cars get 23x@050 cams to drive like stock without bumping the idle much above 800-900 rpm. Hell, I'd tune it for you if you lived here in Lansing... :P

 

I do actually, I live in Temperance, MI. I am sure a trip to Lansing would not hurt it.