Hi all, I've heard of this U-Bend Delete mod. before. I have a little better idea of the concept of this modification from these posts. I have a 07 3.8 Grand Prix GT (supercharged). What do ya all think, would my car benefit from this type of modification? The only mod I have right now is a Cold Air Intake. I would like to get this car up to about 300 horses. Right now I would give it 270, maybe a few more. I don't know if I want to go with a complete reconstruction of the total exhaust system. I don't think its that restrictive.
upgrading performance
- Thread starter ndwings11
- Start date
minichopper6hp
Banned - Busted For Scamming
04-up doesnt have the ubend so you cant do it lol its already there from the factory in a sense.
blueguy
The Blue One
Robotech
New member
I think he is thinking crank horsepower not wheel horsepower.
JGT, realize that 260 rating is at the crankshaft. When we begin modding our cars we test for horsepower at the wheels. Because of the parasitic loss caused by the engine needing to turn the gears in the transmission, the axles, hubs, and finally tires/wheels, 100% of that power does not make it to the ground. Most experts in our community place our drivetrain loss at around 15-20%. Thus if you see someone on here saying they have 300 HP they mean they have 300 wheel horsepower. That would be apx 350-375 crank horsepower. Your 260 crank hp winds up being apx. 208-221 wheel hp.
blueguy
The Blue One
That's what I meant too
I just wasn't in the mood for explaining it like you did :th_biggrin2:
Funny, but most L32 cars I have seen don't make as much power as L67 cars stock for stock...I've just wondered why that was...maybe it was the dyno's being used idk. You would think they would make more because of the GenV :th_scratchhead: Or maybe I just haven't seen enough dyno sheets...
Liquifire
New member
I haven't seen any dyno sheets on this, but I did drive a couple of the 04+'s and was not impressed by their performance both handling and acceleration.....imho....maybe I just wasn't test driving the right ones????? I was looking at getting one for the wife........but it doesnt look like that will happen. I will look for something else.That's what I meant too
I just wasn't in the mood for explaining it like you did :th_biggrin2:
Funny, but most L32 cars I have seen don't make as much power as L67 cars stock for stock...I've just wondered why that was...maybe it was the dyno's being used idk. You would think they would make more because of the GenV :th_scratchhead: Or maybe I just haven't seen enough dyno sheets...
Swash
New member
I got such a hard on reading that...I love it when you use those big, sexy words.
-Swash
Robotech
New member
That's what I meant too
I just wasn't in the mood for explaining it like you did :th_biggrin2:
I'd hope with an I/C, 3.1, and the rest that he'd see more than a 40 crank HP gain! LOL
swash said:
Down boy!
Swash
New member
Sure it is...sort of. If you "just" delete the U-bend - you will stay at the stock exhaust size from the manifold to the muffler = 2.25". If you put in a 3" downpipe - you will help the motor breathe - but you are still going from manifold -> 3" -> 2.25". The "ideal" situation is to go 3" DP to full 3" exhuast - but that can create a cash hemorrhage.
-Swash
Swash
New member
Swash
New member
Actually - that is true - you can run 2.5" and it will be more than adequate. I'm not sure what the diff is between 2.5 and 3" (cost).
-Swash
blueguy
The Blue One
Calvin made mine Shannon...3" all the way from the downpipe back for $250 :th_biggrin2:
Swash
New member
G&C's is the hook up. He did both of my Spintechs and modified my GTO DP a bit - for $50.
-Swash
Robotech
New member
Dang. I'm in need of a new exhaust but I have a feeling the drive to MO would offset the cost savings from getting it done here.
IF you have someone redo your exhaust, I HIGHLY suggest having them center the Y in the back so that the length of the exhaust to each muffler is the same. Ever see a stock GP idling in the morning and notice that the passenger side muffler is putting out more water vapor than the drivers?
IF you have someone redo your exhaust, I HIGHLY suggest having them center the Y in the back so that the length of the exhaust to each muffler is the same. Ever see a stock GP idling in the morning and notice that the passenger side muffler is putting out more water vapor than the drivers?