First a little about this set-up, 383 LT1 with stock heads/valve sizes, ported and polished by Mike Stark @ CFM Performance, CC306 Cam with 1.6 RR, Hooker LT'S, True Dual with X-pipe, and dynomax bullets. This was a little disappointing, but I think there is some room for growth. Tuning by mail order done by Ion Soltan, a local TTA buddy of mine will be helping me work the kinks out in the next week or so. be doing some more tuning in the next couple of weeks.


I had a SES during these runs, turned out to be the MAP sensor connector had broken/fallen out of its socket. Look at the A/F its a little lean 14:1 to 13.5 to 1 at higher rpm's. I think there is 30 or so more HP in it with a good tweaking. If we can hit the right A/F and get the timing worked i think 380 or so to the wheels. That will make me happy. Look at the HP Curve at 5800 RPM there was another tuner on site he said it looked like something was pulling timing. He mentioned that the curve was heading for the 350+ mark but something was falling short. This motor is built for a 250 shot, once the N2O is finallized i will post more numbers.

Car Went 12.51 @ 108.13 with a 1.8 60' 2.73 gears BFG DR's 2800 Stall and 95 Deg temp on a Florida July afternoon. This was about a week after the Dyno Day, and the MAP Sensor working !!!! I ran those times across some HP calculators on the Net, assuming a 3700# race weight that puts the HP from 360 to 380 depending on whose calculator you use.

 

Did you flow your heads? That is probably what is holding you back. I think your going to have some fun with that 250 shot once you get the bugs worked out. My 100 shot is getting boring.

 

No the heads were not flowed, the guy that did them claimed about 265/215 w/pipe Those numbers are not too bad but definately not AFR 215 numbers like I would like to use. However my target is 11's on motor then spray the heck out of it. hopefully netting a high 10 in the 1320 with a lot of susp. mods.

 

Hhmm get it tuned right and see how you do. BTW my car made best power at 13.6:1 so your car may not be that far off... Like mentioned already those heads could be costing you a bunch..

 

what heads are you running on your setup???

 

TEA LT4's...

 

hmmmm...that seams a little weak...I have a 96 TA hooker long tubes, cc 306 cam, STOCK heads and 4.10 gears...I dynoed 353 RWHP and 343 RWT...i dunno i think the heads might do it and those damn 2.73 gears.

matt

 

i have to agree with everyone else.

i have a 97 z with a 355 forged interals 210/224 cam and stock heads that are ported and polished and i put down 403RWHP and 378RWTQ with stock exhaust manifolds. that was with a very safe tune.

i think there is alot of room for improvement.

 

1slowlt1, who did your heads? Those are some nice #s for that cam with still stock manifolds.

 

Jeeez! Is this for real? I'm impressed if so. Nice numbers.

SnkEatr-

There's much need for improvement there in my opinion from what I've seen.
Seems to me the A/F ratio is still a little rich. Though every car is different. My car goes down into the low 12's lean at peak RPM. And it seems to be great. But, I haven't put it on the dyno yet.

 

Jeeez! Is this for real? I'm impressed if so. Nice numbers.

SnkEatr-

There's much need for improvement there in my opinion from what I've seen.
Seems to me the A/F ratio is still a little rich. Though every car is different. My car goes down into the low 12's lean at peak RPM. And it seems to be great. But, I haven't put it on the dyno yet.

 

I would definitely say that your heads are holding you back. I just dynoed 375/363 with a stock bottom end and a 224/230 XE cam.

It's all in the heads.

 

I don't think you mean rich, you mean LEAN!!!
You should fatten that bad boy up for the sake of safety if anything.

Also the bumpy curve usually indicates a timing issue, bad spark plug wire or coil wire etc. You might take a look at those and see if anything is going on.

Great #'s though...

Mike

 

Those are incredible numbers for such a small cam. A little too incredible. Can you back this up with some proof? If so, I'd love to know who did your heads? What's the lift on that Cam? Ect. ect.

I just don't see that happening.

I'm not trying to be a **** or anything, but if this is true then why isn't everyone climbing all over each other to get heads done by whoever did yours and running that same cam???

 

I would say without the MAP connector being attached, the dyno results are in no way indicative of the engine's capabilites. MAP is used for the timing maps, and probably affects the target A/F ratio in PE mode. Without any input from the MAP sensor, the PCM is flying blind in some areas and has to make some very conservative assumptions. Who knows what kind of defaults it uses.


Its the other way around..... "low 12's" is richer than 13, which is richer than 14.7, etc. It's the "A/F" ratio, so a high # means lots of air.