I'm begging you to reply to this post if you have any thoughts on this matter, because this car is seriously driving me crazy and I am out of ideas. Please help!


My car's mods consist of MTI S2 heads milled .030, lunati B1 cam, mac headers, orp, slp catback, PT 4200 converter, all bolt ons.

The car is an absolute turd. It just runs slow for a heads/cam car with a big converter like that. went to the track and ran 12.1 at 111 mph was the best I could do. Most runs were more like 12.2-3. 60 ft times were 1.66-1.7. With the cars less than stellar engine output, 1.66 60 ft is simply all it will do. The car simply does not have the power to take off any faster than that. Those runs were a dead hook on every launch.

I mean 111 mph from a heads cam car with a converter, that's lame as hell. The car ran great when it was stock. I dont have any track times or dyno numbers, but I've been in enough LS1s to know what a stock LS1 should drive like. I'm starting to wonder if there might be a problem with my heads or my cam.

I know the heads aren't cracked and there isn't a blown head gasket, either. Could there be a valve seat problem? The heads have less than 1000 miles on them.

Consider this for a minute. I have the absolute WORST drivability problems with my B1 cam I have ever heard of. The car will stall, stumble, surge and quit ALL THE TIME. cold startup, hot startup, doesn't matter, the car just never wants to idle right. I have done every possible thing with LS1 edit and adjusting stuff on the TB to try and cure the drivability problems and nothing will cure the stalling problems. I would honestly rate my cam on a scale from 0-10 a 0 for drivability. I am not faint at heart when it comes to unstreetable mods, I mean I have one of the loosest converters out there and that doesn't bother me at all. The cam making the car stall 20 times a day, drives me absolutely nuts.

The B1 cam that I hear about others using, it is nothing like the one in my car. The cam that is in my camaro was originally in my 2000 WS6 T/A M6. All of the same drivability problems existed when it was in the 6 speed car, but they were not quite as bad in the manual car. It would still quit.

If the PCM happens to get reset, it takes me 20 minutes of holding my foot on the gas before the car will idle on its own. That 20 minutes thing is no exaggeration, either.

When I had the cam out of the T/A when it was going in the Z it didn't have any visible damage. What if the cam was ground incorrectly by lunati? What if the duration on maybe one of the lobes was way too big or something. That would explain the lack of power and **** poor idle characteristics. My old T/A ran great stock. I could produce consistent 13.2 1/4 mile times with mph in the 109-110 range. With that b1 in the old car, the best I could do was ever 115.

Please help me out, I'm just seriously out of ideas. Do you think there really could be such as a defective cam?

What do you suggest that I do?

compression check?
pull the heads back off and check them?
replace the cam?
check other stuff?
give up and sell the car?

I really need some ideas here

Thanks,
Jordan

 

1. Take your car and get it dynoed. Preferibly with a wide band monitor or Autotap as a very minimum.

dyno curves and wideband info can show all kinds of things. If your curves are not smooth, O2 readings, etc...

It could be something as simple as a faulty MAF. They don't set codes, but drop you about 20-25 rwhp sometimes. I've ran 3 tenths and 3 mph slower with a bad MAF, swapped it out in the pits and presto it was fixed.

Drivability issues would be highly tuning related. Are you sure the cam is installed in the right position and not retarded too much?

Tony

 

have u drilled out the throttle body? i have a T1 cam which is bigger then yours and a ST3500 converter. my car idles great. check the cam out and see if something on it is messed up.

 

I agree take it to a tuner something is wrong. Maybe to much preload on lifters,Just a guess. Good luck on this one.It would suck to take the came out and put another one in and it does the same thing.

 

Dude, the car is not tuned. Have the car dynoed tuned by a professional. All your problem soounds like is dyno tuning. And about your times, that is nothing to turn your nose at. What are you launching the car at? What suspension mods do you have? Another thing, you said you were using LS1 edit. What are your idle air counts? I know that on A4 cars that TB bypass hole MUST be drilled bigger. Some even need you to start a second. Dont panic, and dont sell the car.

 

I too agree taht its probably something wrong with the tuning. I would first tkae it to a professional and have it dyno tuned. It that doesnt seem to work, open up the motor...

 

when i put on my heads,cam and boltons i never had the problems you're having.you could have a number of things like knock retard,ect that will kill power.i would go to speed inc,agostino racing some place with everyrthing to do the car right.in 3 weeks i'm going back to agostino to get my new motor tuned, maybe you'll want to go too. goodluck to ya man, mike c.

 

But the specs might differ, and even the slightest difference can baffle the computer.

 

Ok, sounds like it's probably either tuning or something causing the tuning to be off. I'm gonna try and take it to a dyno and atap it at the very least and then have it tuned.

Thanks for the info.

Jordan

 

Stock wheels front and rear, no weight reduction on drag radials? Car should go 11.6@114-116mph I think.

If you are near APE, you might want to get the car tuned on the dyno. If the car surges a lot at idle that means it's too rich. It's hard to say what's happening but I bet you are going like 86-87mph at the 1/8th... You might need some engine tuning and might also need to revise your shift points. Shoot for 6400/6400 shift points, 12.7:1 AF, and 880-900 02's at WOT.

 

I agree with PSJ, give Kirk a call at APE. He is very good with LS1's. Infact he installed and tuned my B1 stock heads to 373hp/370trq on his mustang dyno.

http://www.ap-engineering.com/

 

PSJ,
The times were on ET Streets, the weather was around 95 deg out, hot as hell. my 1/8 mile mphs were 89-90. I'm shifting a bit higher than 6400, maybe I should back it off a bit and see if that helps. Im going to try and get the car on the dyno next week.

Thanks again for the info.

Jordan