Thread: Confirm what all has been done to my car, help solve the mysteries!

As the title states, I would like to enlist the help of fellow GP enthusiast to help me confirm what all has been done aftermarket wise to my 99 GTP based off of folder full of receipts and invoices. There are a few obvious parts and components that I can see clearly do match up to the paper work but needing help confirming the rest. I have a long list of what I was told has been done to the car along with a pile of paperwork...my issue I guess, is that for what all has been done to this GTP I expect more power out of it? It is quick for sure but being modded to the gills, figured it would damn near fly if wings were added. I would also like to know for repair/replacement instances and of coarse what all I can do or add as I can never leave well enough alone and seems like EVERYTHING has been done on this car already.

Can definitely upload better pictures if that helps as well.

Thanks in advance!!!

To start, here is a short list of what I was told is done as well as what I can see (sure I am forgetting or missing something):

Upgraded pulley for the supercharger (obviously not stock, but has no markings..any way to check size, is it as simple as measuring the diameter?)
MSD coils
Exhaust (receipts for both magnaflow mufflers and SLP? haven't yet looked under the car)
Headers (there is a sticker for TOG headers under the hood, anyway to confirm brand as did not find receipt)
Fuel/air chip (not hooked up currently but in the glove box as well as a receipt)
Baer Brakes
Intercooler (stage 2 zzp according to paper work)
PRJ Fuel rails (paper work says 42lb injectors, any way to confirm?)
BMR Braces front and rear
Fender braces
ZZP dog bones
alternator rewire kit
Python alarm system (key fob batt's are dead...might have remote start, anyone with experience here)

Below is a smaller list of what may be done but do not know how to confirm (also have been trying to track down original owner as I would love to pick his brain on the car)


-How can I determine if the car is indeed cammed? (paper work states zzp XP cam along with upgraded rockers, springs, ect)
-Any identifiers to let me know if it does have zzp aluminum heads as an invoice states?
-Found invoice also for DHP tuning...anyway to confirm, will the PCM have branding or markings?
-Upgraded gears (3.29 iirc)
-ZZP trans rebuild according to paper work (will this just be internals or with the case have any markings?)
-Meizer electric fuel pump (cant quite see at quick glance)
-Smaller tooth reluctor wheel (first...what does this do anyway and does it matter if it is there or not?)
-High velocity throttle body? found receipt only marking I find says "Hitachi" and seems to have a spacer?

Again sure there is more here that I am missing and is a lot, that is why I am asking for help even though I am asking alot. Thanks

Ps, something else I found odd...all this work and parts and no indication of a way to monitor KR? There are autometer boost, water temp and oil pressure gauges in the car so unless another gauge was mounted else where or it was monitor through tuning software (DHP?) I dont see how this may have been watched. Maybe he didn't with all the supporting mods to reduce KR (headers, inter cooler, ect)?

Just measure the pulley, it looks really small like a 2.8 or 3.0.

MSD coils are worse than factory, many see problems.

If headers say TOGS, then they are TOGS. The other guys headers is the name.

Pull the injectors to really see what they are or read the part number off them.

A XP cam is going to have a lope to it at idle unless the idle rpm is really high. You'd have to remove it to see exactly what cam it is, they grind the specs into the cam on one end.

Aluminum heads are pretty easy to spot because they are aluminum. Factory cylinder heads are iron.

Electric water pumps have no pulley, so that's easy to spot.

Tuned computers with DHP use the factory computer still, there won't be any markings saying it was tuned with DHP. It will just have the GM sticker on it still.

With no scangauge to monitor the engine it's hard to say if this thing was even tuned right or running correctly.

looks like a 3.0. lets hope its not a zach howard tune. if it came from CO. that guys a total hack.

you need a way to scan for kr. t app, aeroforce, scangauge pick one.

only way to find out just what cam is installed is to pen the engine and see it.

I'd get a fresh tune in it before you drive it too much, I would never trust an unknown tune.

Yes, HP Tuner could see if it was tuned.

You'd either have to know what stock parameters look like or know stock numbers in certain tables or just find a stock 99 GTP file from the repository and compare it the file pulled off the computer. Then you could see anything that looks different than stock.

hp tuners works.

TOGS are headers, they replace the stock exhaust manifold. they are a good brand of header to have too.

Originally Posted by dblackston

Ok great thank you. I dont personally have HP tuners or the knowledge but know local LS guys that do who may be willing to take a look and I could probably locate a stock file and do the comparisons.

hp will cost your friend credits to read your pcm. how they do it, you pay to unlock each car, or pay more and unlock a full year.

Originally Posted by Scottydoggs

hp will cost your friend credits to read your pcm. how they do it, you pay to unlock each car, or pay more and unlock a full year.

Actually.... they can read it for no cost. It's modifying the file / flashing that you need a license for. Scanning and reading is free if you have the equipment.

Yup, you can pull any file you wish and read it for free no matter the vehicle. If you want to edit the file it will cost you money/credits.

Pretty sure you can edit any file without it being unlocked, just need to unlock to flash it.

fpr all you know its fine. only way to find out is to scan it for its long term fuel trims, timing and kr. if you have a droid phone and 15 bucks you can get the torque app. works as good as a dhp scanner. i got both, so i know first hand.

down load torque scan, its a free add on. after that you should see more pid's.

the pid's are listed alphabetically, kr is listed as knock retard.

You can see the mount for that shock thing in the photo posted, right between the dogbone mount and the diagonal brace...