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having nothin but problems needing some help

geiger92

geiger92

New member
i got a 2000 Grand prix gtp with a comp cams, xp-hot cam specs are: 212/224 deg at 0.50" intake lift, .325" (.536" lift at 1.6:1 rocker ratio) 116 lobe separation and it has 1.7:1 rockers on it. 3.1 size pulley that i know is WAY to small producing 10lbs of boost witch is rediculously high i still have stock injectors i need new bigger ones 105lb valve springs and my car is running lean this is the third time this engines had issues n had to be pulled out im wondering if anyone else is having issues running lean, my air to fuel ratio is a mixture of 14,15,16 jumps around i think there suppose to sit at about 12,13 im wondering what to do what do i need to do with my pcm or computer and whats a way i can avoid running lean im wondering if anyone else is having this problem and whats a way to avoid this? some help would really be appreciated
 


Those readings are from a wideband?

No exhaust modes?
Is it tuned?

14+ is lean to the point of hell!!!

You want it in the 11s
Try tuning it, that car is probably knocking soo haard!

Do you have access to live data?
Check inyector duty cycle. To see if you need bigger inyectors.

Just pulley up.
 
You need to do a few things here...

First- read this thread closely- http://www.grandprixforums.net/safely-modding-your-3800-powered-car-17482.html

Second, pulley up to a stock pulley before you blow it up, because at the rate you are going its going to melt some pistons real quick.

FLOW MODS!!! You need headers, u-bend delete, etc... Covered in the 3800 modding thread.

How are you scanning for this? Aeroforce? Laptop?

Why did this engine have to be pulled? Did you blow it up already? If all it was doing was running lean then really no need to pull it. Just put the supporting mods on it, get a REAL tune and go from there.

Hope you can save it.
 
10 psi is fine for a cam and headers.

Afr of 11.0 to 11.4. Minimum 16* wot timing.

Hope you have vendor valve seals and modded retainers though.
 
well got the engine out and stripped down and to machine shop..#1 was a complete melt down..it had way too small of pulley and too small of injectors for the cam .machine shop did some math and figured i was pushing compression past 15:1 with the way it was set up.leaned out hard..block took enough damage it is getting bored..luckly crank is fine ..so it looks like i bought a very fast time bomb..and the timer wasnt set for very many minutes..heads are getting redone and set up proper. all things that should have been done when cam was installed by previous owner..grrrrrrrrrrrrrrrr..so thanks guys for all the help , im now enrolled in the mechanical school of hard knocks , so hopefuly with this education program i will be able to help others out as well in the future..dropping a non supercharged 3.8 in for now to allow time to do this thing up right..i sure appreciate the help from you all..
 
Hopefully the machine shop knows to align bore the block before installing new bearings. These motors like to blow up shortly after a rebuild if the bottom end isn't done right.
 


Please list the rest of the mods to the car.

Exhaust
Headwork (because 1.7's on an XP and you at least have to have the valve guides milled or you'll automatically have trouble.)
Headgaskets, which are you using?
Supercharger Gen 3 or Gen V?

Off the bat, it looks like you are running a smaller pulley than you are ready for. At least pulley up to a 3.4" until you get some things figured out. Then go back down as you learn. Springs, I'd think you should be on a stronger spring (say 130#) for that lift. However you should have a timing chain (double roller) to go with them.
 
I take it you have headers? 10 pounds seems right on the money for an XP, headers build with rockers and so on. Honestly, it looks like all you need is injectors and a tune. That should be a priority as soon as you get a new block in there. Should make a pretty fast car, and solid build.

Now if your heads aren't set up for the lift, that's a whole new can of worms.make sure you have at least 90# springs in there with the XP cam, and get rid of the 1.7 rockers, or have your heads clearanced. I'd buy your 1.7s and you can get a tune with the money.
 
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