Dynamometer Results & Comparisons - lq4/l92 torquer v2 40rwhp gain from removing flowmaster

my numbers are low as shit tho..lq4 with l92 heads and a torquer v2 camshaft with 1 3/4 headers I believe...through 4l60e with 3500 stall (converter was locked on pull I think) with 3.73 gears

Chris Tuten dynoed it at The Muffler Shop of Columbia on a dynojet

has 4" flowmaster merge redused to 3.5" then into a 3" flowmaster (not sure what it is, doesn't say, came on car")

1st dyno pull was 358rwp so we stood there looking puzzled, I figured it would be a little low but not that low...the AFR was 11.9 (rich) and timing was only 26.5..so I told him lets remove the flowmaster & see how much closer it gets us...we made zero changes & it jumped from 358 to 398 just like that

tune is not finished yet...my tuner only did a street tune & is out of town, I just paid for a couple dyno pulls to see how far off I was

well thats pretty damned good.

Odd combo you have there...l92 heads and a torquer v3? What's the compression?

Did the A/F ratio change when you pulled the Flowmaster?

Was the muffler a 3" inlet with a single 3" outlet? Or was it the crossflow with an inlet and outlet on one end, and just an outlet on the other end?

it was single inlet with a pipe coming out of each side into tail pipes...it's stock compression so I believe around 9.5-9.7:1 compression...It wasn't an all out build just parts I got for real cheap from a buddy so I'm not expecting too much but still should make more than 400 & we didn't check the AFR after we removed the flowmaster but it's definitely fat

also I've saw a thread where a guy posted 460rwp with l92 heads & a torquer v2 so it's definitely possible to make power with that camshaft..only difference he had an ls2

firing order is wrong for a flowmaster. They are horrible for these cars.

dyno graph updated...can anyone explain why it stops pulling at 5600 rpms? that doesn't look right at all does it?

Well now I see where a good bit of the power came from...The car leaned out a ton when you pulled the muffler off. You need to get that tune adjusted...it's way too lean now. That could explain why your graph flatlines up top.

The straight through design Flowmasters make good power on LS1s, the crossflow style like you have do not.

Some more compression would definitely help.

naw it leaned out because once he unhooked the exhaust he didn't put the A/F gauge back on the car it just stuck in the tailpipes which weren't being used

bump up the timing and add some fuel..those L92 combos like more timing than the LS1/6 engines(usually,anyway).

Ahh I see....

Fucking hate my cross flow turdmaster. Thats crazy.

Removing the restrictive exhaust leaned the car out some...making it less pig rich! You need a better tune...also that cam profile isnt great with those heads. You need a cam that is better spec'd to L92/LS3 heads.

oh god... dont tell me the flowmaster isnt the best thing out there!!!!!!!!!!! :swing:

Stock compression for an LS1 is 10.1:1...and an LS2 is 10.5:1...so you are already down on compression using an LQ4 with dished pistons...therefore you wont make anywhere close to that kind of power with your setup.

I made 460rwhp on LS2 L92 and MS4 Holley hi ram intake long headers

I made 460rwhp on LS2 L92 and MS4 Holley hi ram intake long headers

Yeah, and I bet your compression ratio isnt in the mid 9's like the OP is saying his is...thats why I said he wont make your kind of power with his setup...plus his cam being quite a bit smaller than yours...

The difference in compression shouldn't make THAT much of a difference I don't think..what's the difference in a lq4 & ls2 compression wise? I think it might be 1 tops...& if 1 compression bump equals 4% like I've read that's only 18 horses..either way I hope I can get atleast 420+ out of this thing next time it's on the dyno

You need to get some flat top pistons, a better tune, and mill some heads or get another cam. Theres power left on the table!

I don't post here often (yet LOL)....I'm just starting to gather parts for a LS swap into my mustang.
However I did recently do my own "muffler shootout of sorts"...seeing the title of this threat, I figured it would apply....

Here are the results (copied from my post on YB)
We've all heard the rumors and stories, and I admit...I change exhaust a lot due to boredom. I've always wanted to do some sort of comparison, and here it is.

Here are the contestants. I tried to make them all a bolt on "cat back".
Mufflers like the vibrants could obviously be shorter but I wanted to keep variables to a minimum.
My car repeats very well and this wasn't done on a dyno but at a track!
My car is a budget 347, with 1 3/4 big tube shorty headers and a X pipe.



Starting top left and going clockwise
http://i287.photobucket.com/albums/ll144/Shifterlou/7abbd195.jpg

Vibrant race mufflers
Flowmaster super 44's
Mac Flowpath
Pypes race pro (similar to magnaflow/ultraflow?)

Last year I ran the race pro's the entire season.
All the passes today were made in a 2 hour window, so D/A should have changed little.

Up first was the Pypes race pro's (they were already on the car). These are a straight through and most people say they are quiet...but sound good at WOT
Off the trailer it went 11.41 and 11.42 at 116.3
1.57 60'

Second was the flowmasters....solidly the losers of the group. Typical flowmaster sound but the super 44's are a deeper sound.
back to back 11.48 at 115.4 and 115.3
Literally on the first pass when I pulled it into high gear I swear it felt slower than the previous passes with my pypes....and the time slips tell the tale.
1.57 and 1.58 60'

3rd was the MAC mufflers. IF you must run a chambered muffler run the MAC's! These had a chambered sound but definitely different and a bit louder than the flowmasters.
11.46 with a 1.59 60'
11.44 with a 1.57 60'
trap speed was 116.1

Last up was the vibrants.
First these are about 15lbs lighter for the complete exhaust vs the others.
These are LOUD, but sound pretty bad ass.
Ran the rest of the day with these and made 4 passes:
11.38 with 1.56 60' first pass
then we had lunch and I ran a buddy 3 times as the day rolled on
11.34 with 1.56 60'
11.35 with 1.57 60'
11.34 again with 1.56 60'

trap speeds were all 116.5 - 116.6


So ok, I'm a believer....if you want to go fast, find a straight through muffer that you like the sound.
There was a .15 ET and 1 mph difference from the fastest muffler in the test to the slowest.