A few GXP questions....

[jeremy]

#1. The stock wheel sizes are 18x8 Front with 255 tires and 18x7 Rears with 225. Anyone know why? It is kind of strange I was just curious about it.

 

#2. Were these ever available with Navigation? I haven't stumbled across was equipped with such and I wondered if it was even an option.

 

#3. What did these things run in the 1/4? My ass dyno is telling me low to mid 14s, but with 303hp and so much torque I thought they would be quicker then that.

 

#4. What is the aftermarket for the 5.3 like? Is there even one or is it pretty limited?

 

That's all for now. Thanks

[jdcutty]

#1 - The smaller size rear tires were put on to help break the rearend loose when cornering hard to fight understeer due to the extreme weight bias.

 

#2 - Yes they are available with on star turn by turn navigation

 

#3 - 0-60 in 5.7 and 14.3 in the 1/4

 

#4 - Not sure on this one, but my guess with it being fairly new, there is prolly not much out there yet. And they already had to modify the 4T65e to handle the extra torque, so who knows how much more it would handle after that as far as power goes.

[BIGBULS]

I've seen You Tube vids of turboed 5.3 cars making 500+ whp.

 

And even basic bolt-ons will net decent gains from what I hear.

 

 

 

 

As for performance, I have *heard* of 13 second timeslips from LS4 W cars..........with 303 crank hp, I don't doubt it.

 

 

 

And the staggered tire sizes are (as mentioned) to help balance handling balance and reduce torque steer. Good luck finding an all season that'll work though

 

 

 

 

 

[jeremy]

 

#2 - Yes they are available with on star turn by turn navigation

 

I have seen the onstar....no indash navigation though?

[jeremy]

 

 

As for performance, I have *heard* of 13 second timeslips from LS4 W cars..........with 303 crank hp, I don't doubt it.

 

thanks for chiming in

[jdcutty]

No i dont think that in dash navigation is available for it.

[Euro]

I could've sworn in dash nav was available in GXP's. It's factory on the Comp G's so I don't see why it couldn't be in the gxp.

[Euro]

ooop, hit POST too soon. GXP's(at least 07/08's) were available with in dash voice-activated DVD based nav.

[Nick1234]

from what i have seen, right around 14.3 -14.4. Only thing i dislike about the gxp is the grille. looks stupid.

[xtremerevolution]

Its pretty disappointing to find that they mated a 4T65E to a 5.3L V8 instead of the 4T80E that they're using on the Northstar 4.6. IIRC the difference in the transmissions is pretty significant.

[5speedz34]

You looking to get one?

[jeremy]

You looking to get one?

 

I"ve been looking at them but I don't know alot about post-gens . Not sure if I am getting one or not We will see how things turn out.

[bdyman]

i have a 05 gxp, with the navigation radio, and the updated disc for it too, i works pretty good for being a factory device, and yes it is voice controled, and i have on star direction /connection plan and when iam lost they download the info to my car and i see it on the screen its freakin sweet

the 18x8 18x7.5 tire combo is to reduce torque steer, improve handling, and gives it the "on train track" feel, and the weight up front, honestly you dont even feel the difference when driving this car and it does handle very well, the bilstien struts gives it a firm a real firm ride its lowered from the factory a 1/2 whoo hooo

there are allot of guys running low 13s with factory cars, and the trans is beefed up to handle more power , see ls1tech.com for more info, the aftermarket is what it is becasue its front wheel drive not allot of companies are fallin over them selves to make products

k&n makes a warm air intake for it, i love mine

hp tuners

diablo sport hand held tuner

vector motorsports ecm and tcm re tune

cat back magnaflow, mine is custom made and it sound great

pfyc.com makes a hood for it, and a different wing

i have goodyear f1 tires and i couldnt be happier with them

w-bodystore.com has some products for the car

sprint springs

ssc spring

eibach no longer makes a spring but they did

intrax makes a spring

05-08 grand prix springs fit on the gxp its the same strut as in the regular car, even the comp g

hogan performance makes a bigger down pipe catted or not catted up to 3 inch , allot of guys love the results

coldairinductions.com makes a real cold air intake kit

allot of prodcuts from the ls2 fits on the ls4 as the ls4 heads up is the same, allot of guys have done roller rockers, ported and polished head work , ported upper intake, ported throttle body, the turbo guy his car was the guinne pig for cartunning turbo his trans was also beefed up then what was done at the factory, from what he says not one problem with the kit

i have had allot of small issues with the car but overall i cant complain its a great car performes great, i just wish it didnt have the dod system to make it a true v8

 

 

[5speedz34]

You don't like the '99?

[jeremy]

You don't like the '99?

 

I love my '99, but getting a car with 30-50k on the clock and a 100k powertrain warranty instead of 140k with no warranty would certainly give more a little more piece of mind...

[5speedz34]

You don't like the '99?

 

I love my '99, but getting a car with 30-50k on the clock and a 100k powertrain warranty instead of 140k with no warranty would certainly give more a little more piece of mind...

 

Very true but you're going to spend alot more money buying that car right?! Plus there isn't much of an aftermarket compared to a L67 car.

[jeremy]

btw...I went back to the dealership today and they were closed all day....WTF is up with that? When my dad was the finance manager at the Chevy dealer they were open every Saturday, even in the winter....

 

[Nick1234]

im sure you are aware of this, but since the 5.3 is such a tight fit, i recall it being very difficult to replace things that should not be difficult to replace. something to consider when the warranty is gone, or you have to fix something that isn't covered.

[jeremy]

im sure you are aware of this, but since the 5.3 is such a tight fit, i recall it being very difficult to replace things that should not be difficult to replace. something to consider when the warranty is gone, or you have to fix something that isn't covered.

 

I was hoping to go back to the dealer yesterday and nose around under the hood to check things out better when I wasn't on my lunch hour but like I said before they were closed. I have a couple that I have my eye on and will be making a few calls on again tomorrow. We will see if any thing becomes of it.