Considering gtp purchase, have ?s

[cadillac adam]

I am looking for some advice on the ups and downs of the gtp's from 97-03 and 04+. What advantages does on have over the other? My mother has a 98 with 150K miles and it runs like a top. Are the newer ones mod friendly? If I het one I'm only looking to do mild mods like a pulley/cai, possibly alc/meth inj. Looking for a fun daily driver!! Thanks in advance..

 

[murphinator]

97 & 98 have a throttle body with a post in it and a more restrictive stock intake than the 99-2003 do this engine is called the L67 (series 2 SC)

starting in 2004 the L32 was the new engine designator (series 3 sc) below is info on the L32 from wiki but it doesnt mention the much stronger powdered metal connecting rods in the L32's:

L32 Supercharged
The L32 is a supercharged Series III. Introduced in 2004, the main differences between the L67 and the L32 is the L32's electronic throttle control, slightly improved cylinder head design, and updated Eaton supercharger, the Generation 5 M90. HP output is up to 260 hp (190 kW) in the Grand Prix GTP.

Applications:

2004-2005 Pontiac Grand Prix GTP
2006-2007 Pontiac Grand Prix GT

the L32 cars did not run any faster or quicker than the L67 cars due to increased torque management but HP tuners can fix that problem easily enough

A lot of people modding 97-03 cars seek out l32 components such as rods & gen 5 blowers as well as complete long blocks


the stock L32 short block has been used in a car running 9.0 @150 , it is stout

alky injection has been tried by several 3800 sc modders no one ever seems to get good results out of it in that application - we need a good GN guy to figure out alky for the 3800 crowd , it seems to work so well on the turbo cars

 

[Torque Overhaul]

It's important to note as well that the 04+ S/C is more efficent. Someone wanting to mod can use a larger pulley on the 04+ and get the same amount of boost than from someone with a 97-03 Gen 3 S/C.
I.E.- 3.4 pulley on a Gen 3 M90= 10PSI
3.4 pulley on a Gen 5 M90= 11-12PSI

The above is just an example.

 

[murphinator]

also you mentioned doing an intake & a pulley without exhaust mods - this doesnt always work out so well , even a 3.6 may knock on the stock manifolds & downpipe , especially with the u bend still in place

a set of 1.9 rockers will move more air through the engine like a pulley drop without the increase in heat which causes detonation without exhaust mods

zzp's 1.9 modified stockers are pretty popular and make more power up high , these cars make more power down low than you can hook up anyways

 

[murphinator]

It's important to note as well that the 04+ S/C is more efficent. .

^^this is true on gtp's which is what he is looking at but just as an fyi incase other w bodys are being considered the 04 + Buicks and Chevys didnt get the gen 5 blower , they still used the less efficient gen 3

 

[cadillac adam]

Thanks for the info guys. Is there a prefered tune for a cai, pulley, ext car? What kinda money should I expect to spend on said mods?

 

[murphinator]

Thanks for the info guys. Is there a prefered tune for a cai, pulley, ext car? What kinda money should I expect to spend on said mods?

you can make a FWI for about $75 total that will work very well

either go to home depots plumbing aisle and buy a 3" to 4" rubber coupler , a 22* 4" pvc elbow , 2 feet of 4" thinwall pvc , and a plastic roof flashing with the rubber insert along with a K&N cone filter

or buy 2 feet of intake tubing from zzp or intense , a K&N cone , and a roof flashing -optionally you can heat wrap insulate it like I did here:

if you are going to drop pulley sizes you need to have a scanner to check for KR $200-$300 as well as the tune you are looking for with a cookie cutter mail order starting at $100 you would be smart to just buy hp tuners for $500 and be able to scan, datalog, & custom tune as many times as you want


do you have a particular goal et wise for the car ? for instance if you only are looking for high 13's you can do that easily on a stock pulley without getting into scanners , tuners, with the right intake & exhaust mods

here is the only pass I ever made on stock pulley size:

YouTube - Regal gs (stock pulley 13.9) vs GN

crappy 60 foot on that run it had a 13.7 in it on the 3.8 pulley

tell us your goals and we can help you achieve them without breaking the bank - also most basic mods are bolt on stuff the best bang for the buck is going to be used mods that you can find on forums generally for about 40% off

 

[cadillac adam]

I'd be happy with mid 13s @ 105ish as long as it doesn't hurt economy and reliability. Just basic bolt ons. What do the 04's run stock?

 

[chris mccord]

99 up would be best. 3.4 pulley with supporting mods should run good.

 

[murphinator]

What do the 04's run stock?

at or near sea level with someone that knows how to prep and run an l67 car about 14.2-14.4

here is a link from baselining my wifes car



http://www.turbobuick.com/forums/3800-supercharged-tech/261332-baseline-passes-my-wifes-98-gs.html