More Power
Asked by Kyle Jun 07, 2008 at 05:08 AM about the 2003 Pontiac Grand Prix GTP
Question type: Car Customization
What's the cheapest/easiest way to add power to a 3800 series II S-charged? So far I only have a K&N air filter and am interested in low-cost mods. I heard that those new pulstar plugs will add about 9-10 hp, and they cost about $150 for a set of six. And then theres air induction and high-flow exhaust. Any suggestions for mods, especially specific brands?
14 Answers
try a smaller supercharger pully, it will increase the boost.
since you all ready put the intake on it the next step you need to go with is exaust Ractive makes a a good full exaust kit thats fairly inexpensive and you will also want to put heaers on it it doesn't matter which brand you go with they are all gong to be around the same price range. with a full exaust system with headers you will add about 25 to 30 more hp. Then you can look at getting a SuperChips power progammer to remap the ecu and add about 10 to 15 horses.
Get a tuner and tune it up using that i.e.(diablosport, hypertech, etc) None of those mods are as sufficient if the computer doesn't know what you got. Basically you'd just be waking the E.C.U. up but i would do that next then exhaust (cat-back).
check out sites like www.zzperformance.com www.3800performance.com and www.clubgp.com for ideas.
I agree w/ Derrick, use a smaller supercharger pulley and use higher octane gasoline.
a computer reprogram will add alot of power places like westers garage will make you a custom program for a couple $$ you can also remove the factory speed limiter
Don't waste your money on those plugs, they never add that much power, and if they claim they do they probably burn alot hotter than your current ones, putting fancy plugs in is a quick way to fry your engine, that sort of thing is usually best in conjunction with a high performance starter and ignition sytem, MSD make those type of things, Air induction and headers are probably the best way to go without lots of tech knowledge and money, you might look into underdrive pulleys and ECM module chips that sort of thing might only cost you a couple hundred(cranking the pulley ratio on your supercharger will add power, but also make your gas mileage worse)
I have a 99 GTP and I will list you all that I have done in the order I have done it. By the way without drag radials I run a low 13 (13.2) and a high 12 (12.99) in the quarter mile. Just beware of the transmission. They aren't tuff in our cars. First I did a cold air intake. Make sure yours is truly cold air. Like you will need to make it a box. I got mine from thrasher but it's expensive. zzperformance.com has a wizaired one that is fine. If you don't make it into a box your hot engine air will get sucked in and might cause knock. Then I removed my resonator and since I live in Ohio I also removed my CAT and got O2 simulators also from ZZP. I had the exhaust shop do this for me. Now another thing you can do is get a aeroforce gage from PFYC that tells you a bunch of stuff but more importantly knock. Then I reprogrammed my computer with Digital horsepower also from PFYC.com but ZZP has an even better one for cheaper. Then I got a 3.4 modular pulley and since my car wasn't doing too bad spark knock wise I then got a 3.25 " pulley. Then I got pacesetter headers. Headers are outrageously expensive for our cars. Pacesetter has cheaper really nice ones that ZZP sells and they even have bigger primaries than the more expensive headers. Now I am listing everything I have but that doesn't mean you have to do everything I am saying. I then got a ZZP short stack intercooler and pacesetter 3 inch exhaust because it is a racecar for me and I don't care too much about sound. It doesn't sound bad but you should only go with 3 inch exhaust if you have enough power. ZZP is extremely helpful and if you send them an email with your exact question you posted on here they will help you out. I have used other people before but I trust ZZP completely. I guess if I knew how much you wanted to spend I could tell you exactly what to do. I spent almost $2000 in about 2 years.
and I forgot to mention... I get about 19 mpg in the city and usually 32 mpg on the highway. So as long as your foot stays out of the gas with these mods you should be okay.
low thirteen high twelve. have you tried some expirimentals that may cut close to a second off of that. or is your car a daily driver
i agree with the person who said be careful of the trani. I have a non modified 97 and had to do the trani but my husband has a modified 97 he changed the pulley and a couple extra boosting him from about 270hp to about 320hp and blew overdrive. This can be unfortunate situation can be slowed if not possibly avoided if you drive it like a standard between third gear and overdrive. I do this and only use overdrive when I am not using the supercharger and when over 80 kms per hour. My husband is an automotive service tech and has been for about 10 nor so years so i trust what he has told me. I do plan on boosting the horse power but only slightly because the trani was built for the cars original horse power. If your careful and try to not over load the trani it should be ok but try to start driving your car like a standard to take the extra strain off the trani.