no HP gain
Thread Starter
Instructor
Joined: Apr 2007
Posts: 145
Likes: 0
From: Kingston, On
no HP gain
Hello, hoping somebody could shed some light on my issue. Last year at Carlisle I dynod 371 hp with the following mods. LS1 intake, stock heads,VRX3 cam, stock TB, LT headers no cats and borla exhaust.
This year I added a BBK intake and 80mm TB as well as a set of MTI racing stage 2E heads, high flow cats. I dynod on the same dyno at Carlisle and got 369 HP. I didnt gain a thing from my added mods. Now my tune is finished yet, could that be it? I also logged the dyno runs and could see KR at the upper rpms. Also last year my car was still pulling at 6800 rpm, this year it was dropping off at 6400. I can send the logs and dyno info if somebody would like to take a look at it for me. Thanks, Dan
This year I added a BBK intake and 80mm TB as well as a set of MTI racing stage 2E heads, high flow cats. I dynod on the same dyno at Carlisle and got 369 HP. I didnt gain a thing from my added mods. Now my tune is finished yet, could that be it? I also logged the dyno runs and could see KR at the upper rpms. Also last year my car was still pulling at 6800 rpm, this year it was dropping off at 6400. I can send the logs and dyno info if somebody would like to take a look at it for me. Thanks, Dan
Le Mans Master
Joined: Jan 2007
Posts: 9,844
Likes: 33
From: S. FLA :: Professional Devil's Advocate
Hard to say for sure because dyno power varies a lot based on temps, humidity, etc. You could drive around town and dyno on 4 machines and get 4 different readouts.
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
Most of us think putting a car on the dyno is like getting on a scale and weighing something. You get a number and thats it... There are way to many variables with a dyno.. I just saw a post on here and the guy was making 350rwhp and 385rwtq on a basically stock LS1
Last edited by David426; Aug 30, 2009 at 12:32 PM.
Thread Starter
Instructor
Joined: Apr 2007
Posts: 145
Likes: 0
From: Kingston, On
I would have thought that with a set of aftermarket heads, intake and TB I would have seen a little bit of increase in power. What about the cats I had installed, would that cause the 0 power increase?
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
A proper tune can definitely pick you up power. Don't be disappointed until you know it's tuned correcly. I was running a little lean at the track the other day. I added a little fuel and timing to the tune and picked up 3mph. Did they put a wideband on the car while dynoing it? If so, what was your air fuel ratio?
Thread Starter
Instructor
Joined: Apr 2007
Posts: 145
Likes: 0
From: Kingston, On
the air/fuel at 4000 was 13.77. at 5000 it was 13.41. 6000 it was 13.34 at 6700 it was 12.56. I can scan the dyno sheet if it would help. I also logged the 2 runs with HPtuners. Thanks for the help.
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Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
I noticed you said you made two passes with HP Tuners. Are you an experienced programmer or tuner with HPTuners? If not find an expert with HPTuners and let them do their magic.
Just because we can buy a copy of HPTuners or EFILive, does not mean we know how to use it in 2 hours of playing with it.
Thread Starter
Instructor
Joined: Apr 2007
Posts: 145
Likes: 0
From: Kingston, On
the tune it it right now is just a starting tune for it to run alright with the mods I have. I have an experienced tuner that will be doing the full tune for me. I logged the 2 passes. I hear you about buying the tuning software and being able to tune in 2 hours
I have owned HPtuners for a year and am still learning. just hooked up my wideband in my car last week.
I have owned HPtuners for a year and am still learning. just hooked up my wideband in my car last week.
Safety Car
Joined: Jun 2004
Posts: 4,986
Likes: 393
From: Stoney Creek Ontario
prob needs to be dyno tuned properly with wide band - my set up is small VRX1 cam, Lingenfelter ported heads, long tubes, high flow cats, UD pully, Yella Terra rockers, cat back, CA intake, etc, with mods before tune - 378 hp, after tune - 409.97.... had to fiddle with the tune a time or two afterwards, but now drives like stock...screams pretty good when the pedal is pushed though...
