Thread: Just got a GTP, have a few questions for the experts

Originally Posted by Bio248

catless downpipes suck. the cat helps with a deep tone and less rasp. if you have enough money, get one with a cat.

also, youre not going to want to run a 3.4 without a good tune. do all of the flow mods first, then buy a pulley later. your car will feel awesome after you open up the intake and exhaust.

Money's not an issue with getting the right parts, I just dont wanna stick half the price of the car in mods since its just a DD, Was wanting to keep it around the 5 hundo mark if possible but no biggie. So you recommend the 3" DP with the high flow cat then?

Originally Posted by superv6

Well there u go. To each his own. I've never heard a dp with highflow cat. I just know I like the catless dp. But bios right about the pulley. Its really not the most important thing to get a pulley. I've noticed a lot of inexperienced guys will get the pulley as their first upgrade. I would do It different if I could go back and do it again. But yeah these cars love intake and exhaust mods. Plus a good tune. They like that too

I just figured the pulley would be a very effective and cheap mod, I know how GM loves to half ass these setups like by putting a way to big stock pulley on them and quarking up the exhaust. The fender mount CAI I made and put on made a decent difference, I woould think the pulley would be the best bang for the buck, but thats why im on here posting to see what exp says on these cars

Also, do you have to chg the plugs when going to the 3.4 or?? Tried callin ZZP today to order the dp,pulley,t-stat and maybe the plog but no one ever picked up, do they have an acct on here or another num other then on there site? I dont like ordering stuff like that without talking to someone from there first...

And again thanks for all the advice to everyone

ZZP is pretty good about getting parts out. with a 3.4 you might want to run 104s, but its up to you if you want to change plugs. it might help with knock a tiny bit.

Originally Posted by LSXHP

Also, do you have to chg the plugs when going to the 3.4 or?? Tried callin ZZP today to order the dp,pulley,t-stat and maybe the plog but no one ever picked up, do they have an acct on here or another num other then on there site? I dont like ordering stuff like that without talking to someone from there first...

And again thanks for all the advice to everyone

Screw ZZP's customer service...yet again another fail IMO.

Just e-mail them...they seem to get to that quicker.

And I would get a 180* or 160*, Autolite 104's, the 3" Downpipe, Front PLOG and a Tune...THEN drop pulley sizes.

Originally Posted by bluegtp91

Screw ZZP's customer service...yet again another fail IMO.

Just e-mail them...they seem to get to that quicker.

And I would get a 180* or 160*, Autolite 104's, the 3" Downpipe, Front PLOG and a Tune...THEN drop pulley sizes.

Well today they actually answered the phone and the guy actually was on the phone with me for damn near 50 min somehow.He actually said the car would benifit more from a stage 1 TB more then a Plog, that sound right? He also said the pulley is the single best bang for the buck on these cars. The 3.4 he reccommended 1 stage colder plug a Tstat and the Down pipe. He said if I do the pulley before the pcm I just wont see the full benefit of it but is in no way going to hurt anything. I guess on the 04+ cars its a different story but on the 99-03's not at all. I also talked to them about there pcm v1.0, seems like a good piece, said they got a lot of time and research into them, he said there on the concervative side and there unlocked so I could always have it tweaked at a local shop I wanted a more aggressive tune or decided to mod heavier someday.

Originally Posted by LSXHP

Well today they actually answered the phone and the guy actually was on the phone with me for damn near 50 min somehow.He actually said the car would benifit more from a stage 1 TB more then a Plog, that sound right? He also said the pulley is the single best bang for the buck on these cars. The 3.4 he reccommended 1 stage colder plug a Tstat and the Down pipe. He said if I do the pulley before the pcm I just wont see the full benefit of it but is in no way going to hurt anything. I guess on the 04+ cars its a different story but on the 99-03's not at all. I also talked to them about there pcm v1.0, seems like a good piece, said they got a lot of time and research into them, he said there on the concervative side and there unlocked so I could always have it tweaked at a local shop I wanted a more aggressive tune or decided to mod heavier someday.

no way that the car would gain more with a throttle body. they just want your money. exhaust mods first. then think about your intake.

My advice to you, LSXHP, is to listen to the guys on this site. I was one of the new guys who added a cia, plugs and 180 tstat and a 3.4 pulley. I was very disappointed with the performance. It was hardly better than stock and from what I hear, could have damaged the engine. luckily I took advice from Bio and a few others and am completely happy with my car now. GET THE PLOG, 3" DOWNPIPE, AL 104's, 180tstat,CIA and an OVERKILL PCM!!! GET THE 3.5 or 3.4 pulley LAST. Scan and be happy!

THIS NEEDS TO BE STICKIED SOMEWHERE!!



Honestly if you have a '97-'03 or L67 powered car drop to a 3.5" or a 3.4" with the basic bolt-ons but for a '04-'08 GenV'ed car you can only drop to a 3.5" or 3.6" as you have to accomidate for the more efficient blower

Originally Posted by 04compggtp

My advice to you, LSXHP, is to listen to the guys on this site. I was one of the new guys who added a cia, plugs and 180 tstat and a 3.4 pulley. I was very disappointed with the performance. It was hardly better than stock and from what I hear, could have damaged the engine. luckily I took advice from Bio and a few others and am completely happy with my car now. GET THE PLOG, 3" DOWNPIPE, AL 104's, 180tstat,CIA and an OVERKILL PCM!!! GET THE 3.5 or 3.4 pulley LAST. Scan and be happy!

He said the pulley just wouldnt be as efficent without a tune, but reguardless I did the cai, just picked up a 180 stat tonight, tomorrow ill order the 3" off road DP. They said i get a $50 credit if I send in my cat so ill just use that towards the 3.4 pulley. So...I'll do it the way the guys on here suggest....thats why im askin......so...next question can some of you guys give me more detail on the tuned pcm deals? ZZ seemed promising, price is nice too ($99) but if I gotta pay a little more for something that vital thats ok. Figured ill install the pcm and pulley at the same time then do the Plog in a month or so. Hows that sound for a game plan?(Also be doing NGK TR6 plugs when I install pulley&PCM)

I just like to hear from the source selling the product too, I also thought that was wierd he said TB over plog....

Originally Posted by Bio248

no way that the car would gain more with a throttle body. they just want your money. exhaust mods first. then think about your intake.

Just wonderin about ur sig guy, why you got 2 pulley sizes listed? Or am I readin it wrong??

Did I not say they were crap? If not...don't buy ZZP PCM's they blow ass. Just wait on the damn pulley and get all of your other supporting mods...why does everyone want to drop a pulley size...just because you have a tiny pulley doesn't mean you have a faster car.

Originally Posted by LSXHP

Just wonderin about ur sig guy, why you got 2 pulley sizes listed? Or am I readin it wrong??

No, he has a MPS, Modular Pulley System...I have 3 pullies...just depends on the weather. The colder it is the smaller pulley I can run Everyday I run a 3.2"...when it is hot I run a 3.25" and a 3.1" when it is bitter cold

Originally Posted by bluegtp91

No, he has a MPS, Modular Pulley System...I have 3 pullies...just depends on the weather. The colder it is the smaller pulley I can run Everyday I run a 3.2"...when it is hot I run a 3.25" and a 3.1" when it is bitter cold

going to only have one pulley..i pullied up to a 3.4 today and that is where it is going to stay until i sell the car. oops, so sad, too bad.

read the KR stickey. the eaton puts in alot of hot air and adding a smaller pulley just increases the hot air. with the stock exhaust the hot air can not escape the engine thus causeing knock. when it knocks the computer pulls timing. pulled timing equals SLOWER car. there have been many of stories of pullied gtps losing to stock pullied gtps. ask bio about that one also ask bluegtp about the motors the zzp pcm blew..

Originally Posted by blowfishRus6

read the KR stickey. the eaton puts in alot of hot air and adding a smaller pulley just increases the hot air. with the stock exhaust the hot air can not escape the engine thus causeing knock. when it knocks the computer pulls timing. pulled timing equals SLOWER car. there have been many of stories of pullied gtps losing to stock pullied gtps. ask bio about that one also ask bluegtp about the motors the zzp pcm blew..

Hmm didnt know these cars had that problem, I know my buddies 07 SC/Cobalt is runnin a 2.8 pulley with just full exhaust header and cat back and a tune, but I guess thats the newer technology for ya. Anyone got a link to those guys that have the good pcm's for the mods im doing? Ppl been mentioning overkill and Intense I think it was?

the eaton is gonna put heat in no matter what the technoligy. are the cobolts intercooled?? thats also comparing an apple to an orange. the stock exhaust on a grand prix SUCKS.

INTENSE-Racing.com - G8, Grand Prix, Bonneville, Regal, L67 3800 Supercharged Performance Products.

and overkill is a vendor on here.