I just joined this forum yesterday, I'm very excited to learn more about the mods and advice from everyone. I've had my '08 GXP for a year as of yesterday. I love it.

Yesterday I happened to run into a stock 2007 LS2 400hp Corvette w/ a 6 speed manual weaving through traffic around 3 pm. This guy was just having his way, so we decided to catch him and do a flyby to get his attention. I just left Sonic with my buddy, so my car was already 175 lbs heavier and had a full tank. We pull up at a light next to the Vette and wait. The light went green and the Vette does his launch.....but we weren't that far behind him. I managed to launch well enough and used TAPshift to get within a car of the Vette but after 60 he begins to pull two lengths and it stayed that way until 95 when we all shut down. We spoke to the Vette owner at the next light and he was surprised my 4-door GXP was that close to him. He said he was stock and asked what I had under the hood. I told him we both have GM LS V8's. He seemed bummed but was more amazed at the fact that a Grand Prix had a V8.

I don't really consider it a loss, but more of a benchmark to see where this sweet thing compares. What mods can I add to immediately improve my top end? Headers? Tune?

 

Welcome to the site.

Your list of future mods is pretty spot on, except you won't need a downpipe with the headers. Other than that, welcome. I would have liked to line up with him It'd be interesting from a dig. Good job on showing him what we can do!

 

Welcome!

Nice race, though I'll need to call "bad driver mod" on the Vette. Your GXP with driver, passenger and fuel (not knowing your weight) is probably going to be somewhere between 3800-4000 lbs. The average C6 Vette with fuel and and even a fat-*** driver is going to be no more than 3500 lbs, and probably less. Factoring in the 100 HP advantage he has out of the box, you should not even have been able to read is his license plate at 95 MPH, let alone be within 2 cars.

Good job keeping, up, but dude probably didn't know how to drive. As far as mods are concerned, you'll be hard pressed to keep up with an LS2 Vette unless you get real crazy with mods. Like AG said above, headers and tune are a good start. But you'd also need an LS6 or similar intake swap. Upgraded 1.8 rocker arms and better springs also free up more power. Of course, at this point, your tranny would be on it's way out, so you'd need to get that done, too...Otherwise, you risk spitting your torque converter out at the pavement!

Even after all of this, you MAY be able to stay within a length or two of a well-driven LS2.

 

Agreed. A bolt-on GTO on the bottle put one car on a bone stock LS2 GTO here locally. It had to be driver.

 

Yup...Bad driver mod is the cheapest way to go slow!

 

welcome and agree with the fellas on the driver of the vette.

 

I totally agree he wasn't a good driver. That's what made it fun. He did fishtail a bit now that I remember.

Thanks for replying so promptly. I just want to make my GXP a solid 13 second car.....I don't want to ruin its reliability due to it being my daily driver.

Has anyone tried drag radials? If so, which ones are best for our cars?

 

Unfortunately, our cars are unreliable without mods, due to our notoriously weak transmissions and uber-crappy torque converters. I would never put drag radials on one of these cars without a built transmission.

 

what he said ^ i'd have to say these cars have easy potential to be 13 sec cars.

 

Welcome

 

13s are easy with exhaust and a tune.

I've run DRs...lol

 

i'll say it again , youre a savage in that monte.

 

not to hijack the thread, but alabamaguy what size of dr's have you run? where did you get em?

 

I believe his borrow a set, and didn't net great results to went back to a street tire.

I run 255/50/16 BFG Drag Radials, which don't help any GXP guys out! I don't launch very hard to stop from hurting the trans. I needed the DR's for my local track, that has horrible track prep.

 

i cant put smaller than a 17" rim on my car thats the issue, ive been looking for dr's for a while now.

 

They sell DRs in 17s. And no, weight transfer was a PIA so it didn't do too hot.

 

that must have been one small shot of nitrous, like a 50 shot. Or possibly not setup correctly.



Oh, you might want to add an air intake to that list of mods.

 

Didn't purge. lol Nervousness. It's set up right, guarantee it. Still a small shot, though.

Air intake?

 

13 sec car thats easy look at my sig \/\/

 

oh ok, without a purge it ain't gonna hit as hard.

Air intake = CAI