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txslow6's 97 TGTP

txslow6

New member
I purchased this 1997 Grand Prix GTP in March of 2010:
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As you can tell it was altered by the previous owner who was a local member of a different forum.

Most ask about the suspension/wheel setup:
Eibach Springs
Otto Racing front Strut bar
Aurora rear strut bar
GMMPP sway bars
GTO spring blockers
18" HP design wheels
SD Hood

Other than the that it had a HAI, 3.4 pulley, 3" downpipe, and 2.5" catback piping through stock mufflers, Intense PCM.

At it's first mod day:
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The $3,000 trophy :th_laugh-lol3:
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Then took it on it's first long distance road trip (1,000 mile round trip through Texas portion of Route 66)

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Back at home for a car show next to my SHO:
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The lower intake manifold gasket had been leaking for some time. Started to pull the top of the engine apart. I also disassembled the M90 to convert it to use in the turbo setup.

Rotors and snout separated from it's case. I forgot how God awful the smell of supercharger oil is.
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The case on the left is what's left after the "guts" were removed. The case on the right is off a 2000 M90. The main difference being the vacuum tree that comes on the 97.
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Fuel rail is removed.
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A tasty 187,000 mile injector. In the words of Ace Ventura- "Yummmmy"
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Blower off.
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M90 case painted.
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M90 block off plate on....
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Re: txslow6's 97 GTP

Everything bolted back on the case and ready for reinstall.
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This just looks funny.
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Ready to move under it's own power again.
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Old Trans:
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Amazing how much better a car feels all around by simple maintenance.

List of things replaced
-rear main seal
-timing cover gasket
-oil pan gasket
-oil pan repaired from the huge dent in it
-built trans installed
-driver side swaybar endlink
-lower engine mount
-trans mount
-driver rear window regulator and pw motor replaced
-alignment
-subframe bolt (one was missing)

No more oil leaks FTMFW!

NA L67 dyno time:
Before the cruise up to GSS:
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Disregard the finger lol
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At GSS:
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Lou decided to stop by and see how his son's dyno day was going:
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Dyno time:
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1st pull 135hp/157tq:
‪NA L67 dyno‬‏ - YouTube

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2nd and 3rd gear pull:
‪NA L67 dyno 2 & 3‬‏ - YouTube

2nd pull: 142hp/171tq
3rd pull: 141hp/164tq
:th_laugh-pointup:
 
Re: txslow6's 97 GTP

Did some work to the GTP

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Had to hack off the tow hitch closest to the the driver side. This is to allow both pipes room to get to the fenderwell.
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Notice how shiny the rear manifold "holes" are?
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Out with the old
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in with the new 42lbers
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o2 sensor out
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Bye bye dp
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block off plate installed as well as wastegate loosely installed.
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Couldn't get the stud all the way out as it was still there and wouldn't allow for me to install the y-pipe cross over. Had to remove the manifold and hated every minute of. The blockoff plate, plug wires, O2, and plugs had to be removed to allow the manifold wiggle room.

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Wastegate reinstalled
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Spent a good deal of time ziptieing the wires(and rerouting) and vaccum hoses away from the exhaust. Paranoia got to me as I became obsessed with this portion. Then I came across the turbo sitting on top of the wires to the PCM
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I have a limited amount of space to work with. If I lean it up against where the headlight goes the airfilter for the turbo gets in the way. Can't move it close to the fenderwell cause the intercooler pipes are in the way. Also I have limited wiggle room with the wires. FML

After trying a dozen different ways I finally figured something out.

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I ended up having to remove the clip that is by the radiator to snake the harness a little more. Then I was able to rotate the PCM just right. Then took the remaining harness(to trans) and wedged it between the drier and frame rail. Pushed the PCM down on top of it, then ziptied the wire going into the trans around the A/C line. Hopefully this helps anyone else who becomes stuck with this portion on their 97.
 
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Re: txslow6's 97 GTP

Jackstand racing:
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New oil sending unit that is not functioning with the autometer gauge:
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T-fitting for the turbo oil feed line and sending unit(ignore the crappy CV boot):
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Crossover and upper dp wrapped:
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Had to cut off some of the bottom plastic to allow a little better clearance for the IC pipes:
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Everything should(in theory) be in order with where the PCM is now:
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TB tapped with an exhaust header stud to block off the PCV passage:
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External MAF installed-I actually ended up removing it due to the plastic on the bottom melting from the turbo:
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Ready to start:
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IC piping all snug and tight:
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Ready to drive on the road again:
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I still need to acquire a boost controller and fuel pump rewire. Also some fittings to try and get the previous sending unit back on. The problem I’m running into is the previous one is freaking huge and I’m limited on space. I will probably have to use a few elbows to find the right angle. Scans were decent, but still need double check the vacuum lines. My scan fluctuated from -18 to -20 for the LTFT.

Finished up the dyno run. They couldn't get the wideband exhaust gauge in the DP.
40% Humidity on 13PSI(stock heads, cam, MAF, and a CT tune):
266hp/293tq
It's about where I thought it would be.
Now I just need to get the rest of the bugs worked out, get a real tune, and install the L26 intake.


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Dyno video of my GTP for anyone that cares:
‪Turbo GTP (1997)‬‏ - YouTube
 
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Re: txslow6's 97 GTP

Resolved the hood latch issues
What you will need:
2 1/4-2 1/2 exhaust clamp (you can find them at Autozone etc)
Welder
Friend
Sandpaper
10mm socket
Rachet
Damp towel/rags
Vice grips
Remove the bolt and u portion where all that remains is this:
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The part of the exhaust clamp you will be welding should look like this:
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First you need to unbolt(3 bolts 10mm) the hood latch where only the mount remains.
You will need to sand the bottom portion of the latch where the weld will take place as well as the bumper.
Your welds don't have to be perfect just as long as it holds. It will be hidden behind the cover anyways.
Go ahead and set the damp towel/rags on the bumper to cover any exposed wires.

First weld the clamp on to the bottom of hood latch mount. Make sure to get both sides and make the bead fairly thick. It should look something like this:
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Here's where your friend comes in handy. Have them take the vice grips and pull the clamp so it is sitting on the bumper.
Tac it real quick to hold it in place then finish your bead-again it can be crappy like mine just need it thick enough to hold:
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Reinstall the latch and adjust up/down as needed. Give the hood a little drop and watch it snap in place.
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Went ahead and wrapped the turbo and reinstalled the external MAF. Seems to be running much better. Next paycheck I'm getting a threaded IAT and I'm tapping the TB where the stock MAF goes.
Here's how it looks now with the turbo wrapped:
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Found a place for the PCM (In the bumper cover) far away from the turbo and cleaned up the engine bay a little.
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Decided to paint the calipers.
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Ordered new badges for the GTP:


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Hope to have someone call BS.

They will be placed were the factory GTP badging was.


I also ordered the valve cover breather as I'm borrowing one
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And last but not least a 2.5" exhaust flange so I can weld it on my factory exhaust and bolt it on. No more race car exhaust. FTMFW. It will be nice to be back in stealth mode.
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Time to get to work. Racetronix fuel pump arrived:
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Started fuel pump replacement. GM was kind enough to design an access panel in the trunk area. Removed the nuts holding it down and here is the module it's in. You can I had already started removing the lines:
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Clip was removed with a screwdriver:
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Pump and bucket dismantled:
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All back together and ready for reinstall:
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I’ll post more as I continue with it. I should have pics up later this week with the new badges.
 
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Re: txslow6's 97 GTP

Nice work, keep it going man. I'll have to check it out when i'm in dallas next time.
 
Re: txslow6's 97 GTP

I like your attention to detail. The strategic retention of the rust ring around the rotor hat is sheer genius.
 
Re: txslow6's 97 GTP

Very nice i like the 1st gen sho too. I also snapped my crossover bolts taking them out.
 
Re: txslow6's 97 GTP

holy ****,,
very nice, well done sir
Thanks it still has a ways to go to get it where I want it. As they say, "Its never finished."

Nice work, keep it going man. I'll have to check it out when i'm in dallas next time.
Let me know next time you are in town.

I like your attention to detail. The strategic retention of the rust ring around the rotor hat is sheer genius.
:th_laugh-pointup:
I went to the other side and realized it, its actually all coated. ;)

That reminds me-ordering drilled rotors and new pads soon. :)

Very nice i like the 1st gen sho too. I also snapped my crossover bolts taking them out.
It seems common in the GP community. LOL




Gonna hack off the factory downpipe in a bit.
 


Re: txslow6's 97 GTP

Looks clean. It was very interesting to see those dyno numbers with no rotor pack.
 
Re: txslow6's 97 GTP

never actually seen this car, good work man.
Thanks I'm glad you enjoy it.

Looks clean. It was very interesting to see those dyno numbers with no rotor pack.
Yea, it was a dog. I was getting passed by smart cars.



Cut the downpipe off the catback. I'll get the flange welded to the catback later:
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Had some issues with the car I couldn't resolve with it not starting and checking everything I could possibly think of. Off to the shop it goes to have a real mechanic fix it.
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Re: txslow6's 97 GTP

Good work.

To think that GM generated roughly 170BHP from a 3.8L engine is mind blowing.
 
Re: txslow6's 97 GTP

Going to pick the car up from the shop today. :) it will be nice to finally drive it again. I haven't driven it in 3 weeks. :(
 


Re: txslow6's 97 GTP

What ended up being the problem?

A few.
-I bent the wrong tab during diag.
-Fuel pump relay pins in the rear of the vehicle had wallowed out the contacts.
-Cartuning PCM Kuntzie sent me with the turbo kit I purchased.

They put the Intense PCM back in and it's running rich. Going to stay out of boost until the new PCM arrives.
 
Re: txslow6's 97 GTP

Oh and not that it matters, but my GTP's VIN wasn't even programmed into the PCM even though all the info was given to Kuntzie's guy. Makes me wonder what else wasn't programmed in to that "tuned" PCM. Just a shady deal all around. I learned my lesson with that seller and hope no else has to deal with what I have.


Made it back home without a hiccup FTMFW!

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On a funny side note when calculating manual miles(odo) and how many gallons is being used(DIC) it came out to 60mpg. :th_laugh-lol3:

There's no fing way.
 
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Re: txslow6's 97 GTP

Didn't no you where a hyper miler! 60MPG! :th_laugh-lol3:

Car looks ****ing mean with no front end on it and that IC sticking out!
 
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