I took the car to A & A Corvettes in Oxnard for the dyno tune this morning.
The mods I have on the car are listed below in my signature. I didn't do a baseline run without the mods because I was so anxious to put all the stuff on when I got them.
So before the tuning the baseline run was;
351 rwhp and 351 rwtq max
First tune and run;
357 rwhp and 359 rwtq max
Final tune and run; 365 rwhp @ 6000 rpm and 363 rwtq 4300 rpm
I was told that there was a little more that could have been pulled out but it would have been on the edge of creating detonation. So I said, "No thanks".
At the crank;
430 hp and 427 tq (estimated drivetrain loss at 15%)
435 hp and 432 tq (estimated drivetrain loss at 16%)
I'm no sure what the drivetrain loss % really is because I've seen different estimates from different dyno shops.
Air/fuel ratio read 13:1 with a small dip to 12.5:1 between 3200 rpm to 6800 at wide open throttle for the final run. But for the most part, it was steady at 13:1.
I had the 1st to 4th, Skip Shift garbage removed and the redline raised to 6800. I didn't remove the torque management because I was told that the small performance gain, if any, is not worth the abuse you'll be placing on your drivetrain. When traction control is off, the torque management is there to prevent your drivetrain from taking a beating as you shift at full throttle (auto and 6M). I was told that it's function is so minimal that removing it won't make that big of a difference. Especially on a street car with little to no mods. A full on race car, well it's a different story. Since I didn't know much about this area, I didn't question it. Also I didn't mess with the speed limiter. There is absolutely no need for me to go any faster than 158 or whatever it's set at anyway. I've done 155 and I don't think I'll be doing that too often.
In my thread "Torque spec for headers" I predicted around 360/360. So when I saw the final numbers I was very pleased. The owner said that some have complained that his dyno gives low numbers. But to be honest, I don't care. I'm happy with the results. For $500 and 1.5 hours of tuning, it was definitely worth it.
Looks good..... And a good call on not going too lean. Common mistake is all these people hop on a dyno and lean the crap out of the engine to create the most HP "Lean is Mean". Unfortunately that also creates detonation and will seriously damage the engine. And as for the top speed limiter, I have personally seen 162 in my GTO, so I am wondering if it really is there???? I have not tweaked my ECU either.
Looks good..... And a good call on not going too lean. Common mistake is all these people hop on a dyno and lean the crap out of the engine to create the most HP "Lean is Mean". Unfortunately that also creates detonation and will seriously damage the engine. And as for the top speed limiter, I have personally seen 162 in my GTO, so I am wondering if it really is there???? I have not tweaked my ECU either.
Thanks. Yeah, I'm starting to wonder about the limiter also. It seems like those with the A4 speak of the limiter more than those with the 6M. I guess one day when I get a wild hair up my turd cutter, I'll try to max out on top end and see what happens.
Charlie actually did the tuning on mine. But Andy has got to be one of the coolest owner's of a performance shop that I've ever met. Very intelligent as well. His original price was $550 but he lowered it to $500 because the tuning didn't take as long as he thought. That is something he didn't have to do but he did. He has truly earned my business. What a class act!
Thanks. Like we spoke of, JBA's so-called "claimed" big gains from their headers was a far stretched. From what I've learned from small bolt ons like I have, if you take the manufacturers claimed hp gain and divide it by 3 or maybe even 4, you'll be more closer to the actual gains you'll see. The headers and wires were 30 hp, the CAI about 12 and I think the catback was around 15. That's 57 rwhp. Not F-N likely! From what I've seen on stock 05's, the rwhp is around 335-340 (6M). With the 365 I pulled, that puts me at 25 to 30 rwhp gain and 15 rwhp of that was from the tune. So without the tune, all I would have seen was a 10 to 15 rwhp gain. So I guess it's true. The best mod (bang for the buck) is a dyno tune.
A little advice: Instead of adding these small bolt ons based on the claimed hp, add them with the expectation of having a component that's superior to stock. Then when you see your gains you'll be pleased rather than disappointed.
Are the JBA's you installed the shorty headers? I was wondering about those as I have seen a couple of threads about them actually making the same power if not less, since the stock manifolds are bigger and lighter than previous ls series manifolds.
Are the JBA's you installed the shorty headers? I was wondering about those as I have seen a couple of threads about them actually making the same power if not less, since the stock manifolds are bigger and lighter than previous ls series manifolds.
Hey guys,
I need help, I have a 67 goat, my rear coils are a little tired. I want to replace them and also raise the rear about 1” to 2”s higher. Does anyone know where I can find a pair of coils that would do that ?
Thanks, John
Hi, hoping someone can help me here, my wife bought a brand new Monaro HRT 427 back in 2008, it has only ever been serviced at the our local dealer we bought the car from, took it in for a service and two new front tires last Thursday and got a call saying the front nearside hub has stripped a...
just rebuilt my 4l60 new converter and trans cooler. Got to temp and lost 1st and 4th took it back and the battery voltage was low. Tried new + terminal and nothing. Any ideas on what could it be? Trans is coming off and getting looked at to make sure everything is good.
Can anyone tell me if the sensor I have circled in the picture is the temp sending unit for temp idiot light on a 68 GTO. The light does not come on when I turn the ignition key like the “gen” and “oil” lights do so I want to make sure it’s working. If that’s it, any advice on testing it?
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