Need help upgrading a 2005 Grand Prix GTP

[Thegr8t7]

Hi guys, i just bought a 2005 Pontiac Grand Prix GTP, with the 3.8 supercharged v6. Bought from Carmax, love the car. I want to squeeze a bit more power out of it. First thing i got a K and N air filter.

I was looking for a pcm reprogrammer, and only one i found was from Digital Horsepower, Inc. Has anyone used this and if so is it a good product?

Also i spoke to a person at ZZ performance, and he suggested their PCM board 1.0 and a 3.6 pully for more supercharger boost.. was this guy telling me right?

I don't wanna put too much money into the car, and i do want to replace the tires for lower profile ones, and mabye get a flowmaster muffler too, just trying to get some advice on which route is better, the PCM reprogrammer, or what ZZ performance is recommending

I never did anything like this to any vehicle i have ever owned, so im a definite novice and appreciate any help, TY.

[RocketImpala]

Check out http://3800performance.com/

[F14CRAZY]

Check out Bonneville Club.com. Tell them F14 sent ya

[GMCSonoma]

clubgp.com

[Gnitro]

Also ZZPerformance.com

[HoeyHimself]

Upgrading? Its not a computer!

You wanna modify, soop up, beef up.

[big swede]

Originally Posted by Thegr8t7

Hi guys, i just bought a 2005 Pontiac Grand Prix GTP, with the 3.8 supercharged v6. Bought from Carmax, love the car. I want to squeeze a bit more power out of it. First thing i got a K and N air filter.

I was looking for a pcm reprogrammer, and only one i found was from Digital Horsepower, Inc. Has anyone used this and if so is it a good product?

Also i spoke to a person at ZZ performance, and he suggested their PCM board 1.0 and a 3.6 pully for more supercharger boost.. was this guy telling me right?

I don't wanna put too much money into the car, and i do want to replace the tires for lower profile ones, and mabye get a flowmaster muffler too, just trying to get some advice on which route is better, the PCM reprogrammer, or what ZZ performance is recommending

I never did anything like this to any vehicle i have ever owned, so im a definite novice and appreciate any help, TY.

When you say you don't want to put much money into it you need to define "much" because that can be a very different figure for different people. With a budget established you will get much better help. The GTP comes with a 3.8" pulley and I don't even know where you would get a 3.6" pulley.

If I were you I would probably get:
Programmer
3.4" pulley
cai
U-bend delete
Rockers

Spend some time over at http://www.clubgp.com/forum/ and there will be plenty of people who will be glad to help you out. Do a few searches to get a feel for what people start with and work your way from there.

[BOOSTINO5]

If You Listen To This Guy At The Bottom Of The Page Your Car Will Not Run Right!! With The Gen 5 Blower You Can Not Run A 3.4 Pulley With Out Spark Knock..i Would Run A 3.5 Pulley With A Thrasher Intake System If You Want Down The Line A Pcm Would Be Nice..i'm Sure You'll Be Happy With The Pulley And Intake The Whistle Of The Blower Will Get Much Louder!! I Would Stick With Zzperformance They Know What They're Talkin About!

[blown gt]

zz performance is good guys,i bought my blower kit from them,headers,1.9 split ratio rockers are a good choice also, s and s headers are a good choice, easy to install and they hold up very well, along with a pcm and find someone that can tune it for you to get rid of the k-r and set your fuel trims, good luck with your project, i enjoy mine

[Gretsch6120]

I'm looking to do the same thing to my 2004 Comp G gtp, try gutting your airbox I did that to mine, poor mans cool air intake. Looks stock but doesn't sound it when you give it the gas, nice whine from the supercharger. But I have to figure out my cooling issues first before I do anything else

[GMfan1111]

Originally Posted by Gretsch6120

I'm looking to do the same thing to my 2004 Comp G gtp, try gutting your airbox I did that to mine, poor mans cool air intake. Looks stock but doesn't sound it when you give it the gas, nice whine from the supercharger. But I have to figure out my cooling issues first before I do anything else

yeah gutting the box is a good start my bro did it to his Riv and he has been very happy with it so far. Another thing to do along with that is to get the K&N cleaning oil kit that is needed to keep the filter at optimum performance. And please define your budget as mentioned "not much" can mean different things and some after market PCM modifications are expensive

[Mischief007]

For a smaller pulley you need:

CAI
Exhaust work
180 T-Stat
1-2 colder heat range plugs

I always forget something. A question like this can be asked on clubgp.com but I prefer to ask on www.gpona.com. These cars wake up to small changes. Exhaust work is something I'm still contemplating on. I just had Magnaflow mufflers put on and they sound amazing (for me anyway). A full 3" inch exhaust is about $2000 CDN that includes nice and shiny headers, downpipe with cat, and full 3" catback to dual mufflers, installed.

Best thing you can do is ask and ask lots of questions on Grand Prix specific boards.

Another Grand Prix store from CANADA: www.getoverkilled.ca

GetOverkilled PCMs are amazing from what I've been hearing.

[Corr69]

I don't mean to be a ****, but you would be crazy to listen to some of these guys and drop to a 3.4'' pulley right away.

The 04-06 GTP has the GenV M90 which already produces more boost than the GenIII on the L67. Dropping to a 3.4'' pulley would simply cause pre-ignition as there is too much boost and not enough exhaust flow. This increases boost stacking, which increases engine temps. When engine temps increase detonation occurs and knock retard occurs as a result. This decreases performance and can cause severe engine damage.

3800performance.com has great prices, but its "stage 1, 2, 3 etc" kits do not provide enough supporting mods for the pulley sizes they suggest.

The safest and most effective way to mod the L32/L67 is to improve exhaust flow. Deleting the U-bend after the cat is a great start. The manifolds and downpipe are also very restrictive so they have to go!

After doing this not only can you tune the engine for more advanced timing(more power/fuel efficiency) you can also begin to increase boost.

CAI/FWI
Ubend delete.
3'' Downpipe
Ported Manifolds/Headers
Tune
Pulleys(supporting mods)
- 3.4 (headers/ported manifolds, DP, tune, A104s, 180 thermostat)
- 3.5 (ported manifolds, DP, tune/PCM)
-3.6 (DP, PCM)
Rockers
Cam
SSIC(intercooler)

These cars can get into the 13s very easily without spending a lot of money or losing any driveability

My Regal GS (S/C 3.8L) has run a best time of 14.4@97mph w/2.2 60ft. This time was achieved with a simple Fenderwell intake, and 2.5 catback exhaust. My 60ft times are also .2 slower than they should be(****ty tires).

[Mischief007]

No Ubend on 04+ cars...we don't have that problem as the previous gens. I forgot the tune that these cars absolutely need if you drop to a pulley. Listen to Corr69, he knows what he is talking about other than some small specifics .

As I said before...Grand Prix specific forums will give you so much more information and then some.

[Corr69]

Originally Posted by Mischief007

No Ubend on 04+ cars...we don't have that problem as the previous gens. I forgot the tune that these cars absolutely need if you drop to a pulley. Listen to Corr69, he knows what he is talking about other than some small specifics .

As I said before...Grand Prix specific forums will give you so much more information and then some.

Ahh. I didn't know that. Well i guess you learn something new everyday right?

I have mixed feelings on the L32. Although its more reliable, and the Gen V is soo sweet, i just hate drive by wire....and torque management.

The first thing I'd do if I bought an 04+ GP is get a tune.