My LS2 dyno, questions!
Teching In
Joined: Jun 2005
Posts: 21
Likes: 0
From: Conover, NC
Originally Posted by 9D9LS
What kind of dyno where these pulls on??
I saw that it was a dynojet
It's pretty typical for a dynojet to show wildly different numbers between pulls. This is where the 3 pull came from. When I have a bone stock car on my Mustang dyno I never see more than a 3-7hp difference between pulls when no changes are made. When you have a loading dyno you can get much more reliable and accurate numbers. As far as being that different I bet if you look at the logs, you'll notice that the first two peak numbers are probably at lower RPM's than the latter ones. (didn't turn the car as hard)This is the only thing that I can think of that would make the numbers as much as 50hp off.
Torque Management will not effect the dyno numbers. The TM kicks in during shifts to be easier on the drivetrain. I just installed three units on C6's over the last couple weeks and they work awesome! No more delay during the shifts! You don't really notice this delay until its gone!
Highly recommended part if drag racing is important!
Highly recommended part if drag racing is important!
Originally Posted by JohnnyZ28
Also, for $250 you'd think it would be a little prettier. The switch and wire would maybe cost $3. I don't see where the other $247 could possibly be.
Teching In
Joined: Jun 2005
Posts: 19
Likes: 0
Yes, just wait for LS2 edit to become availible. Your car was suffering from some serious heat and stock tune issues. The damn PCM's in the LS2's are so sensitive that it really only makes sense to wait for the software.
Best,
Best,
Teching In
Joined: Jul 2005
Posts: 12
Likes: 0
From: Yucaipa, CA
Originally Posted by JohnnyZ28
I just got my 2005 GTO M6 about 3 weeks ago. I drove the hell out of the car and tried to get as many miles as possible. I went to the dyno with 1300 miles on my car.
My first pull was 305rwhp/301rwtq. My second pull was 297rwhp/394rwtq. These pulls were back to back. I know the engine temp was the skinny bar past the fat middle bar. Since the GTO doesn't show actual engine temp Im not sure what it was.
... My third pull was 351rwhp/349rwtq and my fouth pull, agian back to back, was 353rwhp/351rwtq.
My first pull was 305rwhp/301rwtq. My second pull was 297rwhp/394rwtq. These pulls were back to back. I know the engine temp was the skinny bar past the fat middle bar. Since the GTO doesn't show actual engine temp Im not sure what it was.
... My third pull was 351rwhp/349rwtq and my fouth pull, agian back to back, was 353rwhp/351rwtq.
It takes off like a bat out of hell with only a chirp of the tires. For some reason I have never been able to light up the tires off the line, it just hooks up and goes.
...Then again, that could just be me. I've been driving so many FWD cars that love to spin off the line that I subconsciously am afraid to floor it and detonate the transaxle.
I'm also interested in finding out about torque management and LS2edit when it appears.
i've raced a few different ls2 gto's in my car, they dont seem like 350hp, but then again, ive never had that car to the track to see how it traps, I'll walk out stock ls1 cars about as hard as a stock ls2 will leave me. on the free though from an 80 roll i barely got pulled by ls2 gto, by the time 120 came up i was still at his door.
TECH Senior Member
Joined: Nov 2001
Posts: 10,341
Likes: 1
Originally Posted by 9D9LS
Torque Management will not effect the dyno numbers. The TM kicks in during shifts to be easier on the drivetrain. I just installed three units on C6's over the last couple weeks and they work awesome! No more delay during the shifts! You don't really notice this delay until its gone!
Highly recommended part if drag racing is important!
Highly recommended part if drag racing is important!
There is BOTH engine TM AND Trans TM.
You are talking about trans upshift torque reduction which is a table unto itself.
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Originally Posted by TruDynoSports
My thoughts exactly,
I saw that it was a dynojet
It's pretty typical for a dynojet to show wildly different numbers between pulls. This is where the 3 pull came from. When I have a bone stock car on my Mustang dyno I never see more than a 3-7hp difference between pulls when no changes are made. When you have a loading dyno you can get much more reliable and accurate numbers. As far as being that different I bet if you look at the logs, you'll notice that the first two peak numbers are probably at lower RPM's than the latter ones. (didn't turn the car as hard)This is the only thing that I can think of that would make the numbers as much as 50hp off.
I saw that it was a dynojet
It's pretty typical for a dynojet to show wildly different numbers between pulls. This is where the 3 pull came from. When I have a bone stock car on my Mustang dyno I never see more than a 3-7hp difference between pulls when no changes are made. When you have a loading dyno you can get much more reliable and accurate numbers. As far as being that different I bet if you look at the logs, you'll notice that the first two peak numbers are probably at lower RPM's than the latter ones. (didn't turn the car as hard)This is the only thing that I can think of that would make the numbers as much as 50hp off.
I'm suprised Dynojet has not sued them over some of the crap they spread. The truth is that while they have some limitations, a Dynojet will repeat as close as any, actually closer than most Mustangs. 7 rwhp variation on an untouched vehicle, at the same temps, is unheard of here. We seldom see more than a couple hp, if that, if the temps are all equal. Probably the best one out right now is the Superflow. That is what I would have bought if they had been building chassis dynos when I bought mine. I always liked their engine dynos. I looked at the Mustang, but too many of the shops I tune for, that had Mustangs, were having some reliability/maintenence problems at that time. About seven years ago. They are probably better now.
People that are now actually tuning the LS2s know that coolant and intake air temps make much more difference in spark advance than the LS1/LS6 PCM. They pull a butt load of spark advance as the temps go up. That is easily addressed when tuning them. If that gentelman was driving his GTO on a warm day, in traffic, with the AC on, and did not cool it off first, he could easily gain that much power between pulls by simply letting it sit for a while with the hood open, and maybe a fan blowing on it. The LS2 in factory tune, is very sensitive to coolant & intake air temps. Even much more so than the old iron block LT1/LT4. Get an LS2 near warm enough for the fans to come on, and power drops like a rock.
Good luck, Ed
Originally Posted by CHRISPY
TM WILL affect dyno numbers if the PCM calculated torque is higher than the threshold it'll drop power.
There is BOTH engine TM AND Trans TM.
You are talking about trans upshift torque reduction which is a table unto itself.
There is BOTH engine TM AND Trans TM.
You are talking about trans upshift torque reduction which is a table unto itself.
Good luck, Ed
11 Second Club
Joined: Aug 2004
Posts: 891
Likes: 0
From: minneapolis,mn
My o4 gto was going over torque limit all the time Now it's at 640 also and I'm not having this problem anymore. Dynos won't win races so who cares what the hp is. Yes I have mine listed and it seems low to me but what do I know. It's cam and headers only oh a couple bolt ons.
Hey johnny you should just come race either one of my cars and see how your gto does. My 04 only has ten mor horses than your car so it would be a good race.
Hey johnny you should just come race either one of my cars and see how your gto does. My 04 only has ten mor horses than your car so it would be a good race.
On The Tree
Joined: Mar 2003
Posts: 105
Likes: 0
From: Here and there
Originally Posted by Ed Wright
Some people can't accept that the M6 cars have it, but I promise you they do. I knocked close to 8/10th off one M6 GTO's 1/4 mile times by just shutting that off in the ECM. No other tuning changes at all. I'm sure others have seen even more by now. BTW, there are several torque limiting tables in the LS2 TCM.
Good luck, Ed
Good luck, Ed
Teching In
Joined: May 2005
Posts: 28
Likes: 0
From: Upper West Side, New York City/Very Downtown, Houston
Originally Posted by JohnnyZ28
My first pull was 305rwhp/301rwtq. My second pull was 297rwhp/394rwtq. These pulls were back to back. I know the engine temp was the skinny bar past the fat middle bar. Since the GTO doesn't show actual engine temp Im not sure what it was.
My stomach sank to about my knees because I was so disappointed that LS1 GTOs were dynoing higher than my LS2 GTO. I then let the car sit and cool for 30-45 minutes and also disconnected the battery. I reconnected the battery and fired the car up and made two more pulls. My third pull was 351rwhp/349rwtq and my fouth pull, agian back to back, was 353rwhp/351rwtq.
saved. I can call and ask. Thanks a lot!
My stomach sank to about my knees because I was so disappointed that LS1 GTOs were dynoing higher than my LS2 GTO. I then let the car sit and cool for 30-45 minutes and also disconnected the battery. I reconnected the battery and fired the car up and made two more pulls. My third pull was 351rwhp/349rwtq and my fouth pull, agian back to back, was 353rwhp/351rwtq.
saved. I can call and ask. Thanks a lot!
How else does one explain the wopping 394 rwtq on the second pull? Then the loss of 50 rwtq on the 3rd and 4th pulls, while simultaneously gaining 50 rwhp.
(unless you meant to report 294 rwtq for the secon pull)
Maybe you should take the GTO to a diff. dyno.
I dont feel bad paying $35 for 3 pulls 