Performance Tuning and Dyno Tests - Is this Right?

[YouEnvyMySS]

OK, I'm a little confused and don't pretend to fully understand all the intricacies of dyno testing, different types of dynos and so on but I'd like feedback on my situation.

My 2SS/RS was upgraded with a custom cold air intake, and ARH long tubes and cats from engine to stock mufflers. I then had a custom tune to bring all of this into harmony. Here are the results, all figures are RWHP:

Torque:

293 min; 361 max; 330 avg

HP:

113; 351; 262

AFR:

13.0; 13.4; 13.2

WS Temp: 47 deg F

Now, after the tune I can tell you that the car JUMPS at 4,000rpm and really pulls hard from there on up... Not had a chance to do any serious hard running to date, but in sharing these numbers, some are saying that this seems "awfully low gains" considering the mods... the TUNER, on the other hand, thought the numbers were quite respectful and appeared to be approaching 100hp over other LSx engines he's seen that were stock. Yes, I'm kicking myself that I didn't get a run done before the mods, and using the stock tune. As a means of explanation, the tuner told me that the "Mustang" dyno he uses provides much more realistic numbers at the rear wheel (vs flywheel numbers that don't account for all the load losses introduced by the drive train.

So what say you experts out there? The car is AWESOME as far as "feel" is concerned. Is it just naiveté on my part or not having any valid comparison/experience in other high performance vehicles?

Sincerely appreciate the feedback!

[POWERFREAK]

I wouldn't worry too much about #'s...as long as the car runs good and is noticeably faster than stock, who cares, they are just #'s, especially since you didn't get a baseline #.

The mustang dyno is usually a little conservative (numbers-wise)...that said, my LS3 stock did 359hp/362tq on a mustang.

Do you have an L99? What kind of intake? Maybe there wasn't enough air going through it?

[YouEnvyMySS]

Originally Posted by POWERFREAK

I wouldn't worry too much about #'s...as long as the car runs good and is noticeably faster than stock, who cares, they are just #'s, especially since you didn't get a baseline #.

The mustang dyno is usually a little conservative (numbers-wise)...that said, my LS3 stock did 359hp/362tq on a mustang.

Do you have an L99? What kind of intake? Maybe there wasn't enough air going through it?

Sorry - should've been more specific originally... this is the LS3 with 6spd Tremec... CAI was a one-off custom built by a local fabricator... all outward appearances seem to indicate that it's massive. The fabricator seems to know his stuff as well... As for "just numbers" you are of course correct, but I'd love to be able to talk intelligently (ok, BRAG) about the numbers... e.g. if this engine is stock at 426hp (assume that refers to flywheel HP), it would be great to be able to say it's 500 (or whatever)HP today post-mods.

[YouEnvyMySS]

I should also mention this!!! When delivered to the tuner, I had like 1/8th of a tank of gas. Ever since I took delivery in early September I've always filled up at a local BP using their 03 octane.

First attempt at tuning, he could NOT get timing advance like he wanted because the car started pinging like crazy! He brought in 5gal of Shll 93 and was then able to get it "right.

Take a look at the differences in the numbers before & after the addition of "decent" gas, and getting timing "right"!

Min Max Avg (before/after)

HP: 109/113 340/351 254/262
TQ: 285/293 343/361 318/330

Needless to say I no longer buy from that BP dealer!

[POWERFREAK]

Not sure I'd trust a "fabricator who seems to know his stuff" unless he had lots of experience building intakes for LSx motors...but hey, as long as it runs good and it's got balls. #'s-wise w/ your mods, you should be up over 400hp easily.

[YouEnvyMySS]

Originally Posted by POWERFREAK

Not sure I'd trust a "fabricator who seems to know his stuff" unless he had lots of experience building intakes for LSx motors...but hey, as long as it runs good and it's got balls. #'s-wise w/ your mods, you should be up over 400hp easily.

So I'm clear here, "..over 400hp" at the rear wheels? where I'm showing only a max of 351hp on my best dyno run?

[CWI]

Originally Posted by POWERFREAK

Not sure I'd trust a "fabricator who seems to know his stuff" unless he had lots of experience building intakes for LSx motors...but hey, as long as it runs good and it's got balls. #'s-wise w/ your mods, you should be up over 400hp easily.

That's about right. My LS3 got 399 RWHP with ARH headers and 3" to the tips and an ADM intake without the box installed and stock tune.

That's a nice looking air box

[YouEnvyMySS]

Originally Posted by CWIweldace

That's a nice looking air box

LOL!!! Appearance is great, but if I should be seeing another 50hp I'm not real happy about now.

[CWI]

Originally Posted by YouEnvyMySS

So I'm clear here, "..over 400hp" at the rear wheels? where I'm showing only a max of 351hp on my best dyno run?

Sorry, read some of the dyno and performance threads. 351 hp is low even for a stock LS3. You said it had some bad gas, nothing against your tuner, but maybe the ECM needs reset like on the L99s that had low octane fuel in them. Just a thought.

[POWERFREAK]

Originally Posted by YouEnvyMySS

So I'm clear here, "..over 400hp" at the rear wheels? where I'm showing only a max of 351hp on my best dyno run?

YES.

Originally Posted by CWIweldace

Sorry, read some of the dyno and performance threads. 351 hp is low even for a stock LS3. You said it had some bad gas, nothing against your tuner, but maybe the ECM needs reset like on the L99s that had low octane fuel in them. Just a thought.

that shouldn't be an issue after it's tuned.

[chappy48]

I see that you're in Rhode Island. Take a run over to Jannetty Racing in Waterbury CT and have him do a couple runs on your car and check it out. With headers, a good CAI and tune you should be pushing 410-415rwhp.

Edit: BTW, I just looked at your A/F ratio and it's really lean. Don't know who the tuner was, but Jannetty Racing and even the big name guys like Lingenfelter are tuning the car in the 11.6-12.4 range. It's a lot safer on the car and they actually seem to make more power down there.

[POWERFREAK]

Originally Posted by chappy48

Edit: BTW, I just looked at your A/F ratio and it's really lean. Don't know who the tuner was, but Jannetty Racing and even the big name guys like Lingenfelter are tuning the car in the 11.6-12.4 range. It's a lot safer on the car and they actually seem to make more power down there.

It may not have been getting enough air on the dyno (if that's the case, on the street it's probably fine)...but heck yeah, if you're concerned about it, have Jannetty dyno it and re-tune it if the numbers still don't look right.

[Altered]

Ed if you think you are loosing 50HP from my intake please have it dyno run with the stock intake.

[Ravirn]

Originally Posted by Altered

Ed if you think you are loosing 50HP from my intake please have it dyno run with the stock intake.

Considering other threads:

http://www.camaro5.com/forums/showth...ght=stock+dyno
http://www.camaro5.com/forums/showth...ght=stock+dyno
http://www.camaro5.com/forums/showth...ght=stock+dyno

You need to take him up on this offer. I don't doubt the intake, but the dyno run is too low, compared to the bazillion other people who ran stock dyno comparisons to their modded Camaros. Go back and ask for a comparative analysis. Smarter people than I post on Camaro5 (and they have far more experience,) but I'm sure they're raising an eyebrow at your results.