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1989 Ford Probe GT project

7323 Views 93 Replies 11 Participants Last post by  brad46
For this who might be interested I figured I’d start a thread on my 89 PGT...

I originally bought this car back in 1999, it had a warped head due to being overheated. I repaired the car and got it back on the road. A few months later I sold the car to a friend for a down payment on a new home.…

Fast forward to a month ago (23 years later), my old friend messages me via FB and asks if I want to buy the car back- Of course I said yes because I had always regretted selling it.

History: Shortly after he bought the car (in 2000) he pulled the engine and had it rebuilt with Ross pistons, ported the head, had everything balanced, etc..He also bought a bunch of other parts (clutch, etc). Has the receipts from 2001
for everything.

He never put the car back together and it has sat in a heated garage for 22 years. I will be heading to MN (from WI) in a couple weeks to pick it up.

I plan on getting everything put back together and perform some minor modifications and post the progress here..

Here are a couple pictures of the car from yesterday- first time seeing sunlight in 22 years!

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Car Wheel Vehicle Tire Hood

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I am hoping for all the advice your willing to give!
The plug wires I got off eBay and they are a Napa brand..nothing special. I do have the originals that I’ll keep and may throw back on if needed.
I am not seeing the black plastic clips for the plug wires- I’ll be getting these on order asap.

I restored an older snowmobile and took all the nuts and bolts to a local place that was able to re-plate everything. I took hundreds of parts to be plated and they charged me $50! If this car was a complete mint restoration I would go this route.
I have bought a handful of new nuts and bolts for the areas that get seized easily- The areas I expect will be coming apart again in the future I added some anti-seize so they will come apart nice and easy.

Finished up the heat shielding today and got everything bolted on. Also started working on the fuel system, got the old gas blown out of the feed and return lines. The fuel pump (as you can see in the picture) is really rusted up and the screws are not going to come out easy. I am going to pull the tank to remove the fuel pump (and upgrade) and see if the tank itself it worth cleaning up. If not I’ll just order up a new one.

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For the fuel pump, pull the tank off the car and clean the heads of the screws with a wire wheel on a drill, use a blade to scratch at the rust in the screw, find the proper sized screw driver, insert it in the screw head and hit the screw driver with a hammer a few times, if it feels like the head is going to strip keep hitting the screw driver. Some will strip, drill the heads off with a large enough bit, pull the sending unit off the tank, there will be enough bolt stem left ti grab and unscrew with vice grips, the screw are metric, fine thread m4's maybe m5's. Even here in the land of rust the threaded mounting holes in the tank never seem to rust.

I see you used grade 10.9 bolts for the heat shield, good move, grade 8.8 or lower will stretch with heat and seize in the manifold after a few months.

Anti seize won't hurt but F2T bolts and threading don't usually seize in the block or transmission even after 35years.
Just google thread torque and anti seize, all lubricated bolts require less torque to achieve the same clamping force
(less force to tighten as far) so you torque according to whats on the bolts, I use high temp red thread lock on many of my bolts (AWR mounts like to shake things loose) and torque them to the lower end of factory torque spec while the are wet. The risk with torquing bolts wet is over torquing them and stretching the threads, with time the lubricant dries, bakes and the stretched threads get set in that position over time and bind, the bolt/nut/spark plug strips the threads and the weaker surface suffers the most damage.

50$ for hundreds of small parts is a damn good price, I looked into getting set up to do metal plating, it's quite affordable (2 coolers, some acid, some electrodes, possibly a liquid heater and a 12V dc selectable amperage battery charger or power supply and the desired plating) but the durability was questionable at best when coating parts that have already rusted and will see winter in the land of rust. And anodizing wasn't nearly as durable as powder coating for aluminum so I gave up on electro plating.

I have noticed over the years that driving a car all winter after doing cleaning work to the engine tends to have less rust (on the parts I work on) than parking it outside for the winter, the bolts seem to rust faster and the powdercoat fades faster when the car isn't heat cycled every day. The parts I don't treat/coat and cant reach rust way faster driving the car in the winter. Lose lose.
I recommend buying a small parts tumbler to clean all your small stuff, harbor freight has one for 70$, you can take the rust off stuff, debur or polish in one unit, just change the media (shit you put in it), don't have to stand in front of a sandblast cabinet or bench grinder cleaning bolts and small parts for hours on end, just turn it on and walk away.

Your build/restoration is coming along nicely, you are putting all the attention into all the details of what you are working on, remember with some stuff stock and simple is best and with others Custom is King (clutch, turbo, intercoller, pipes, fuel ... ).
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Nice work, I just noticed on your picture a couple posts back you need another bracket when installing. You put on a bracket that goes from the top at the inlet manifold to the bottom of the block (firewall side). On the bottom two bolts you have to add another bracket which keeps the exhaust in place, I think it also bolts to the transmission. Just in case you didn’t know already.
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So I was pulling of my transmission to replace the clutch, and wanted to remove the big bracket on the front of the block discussed a few posts back. I removed the 2 bolts at the transmission and the bracket fell off, in other words: I think the two bolts for the block were missing before I started wrenching on the car. Don’t know how they went missing, but could have been like this for 10,20,30? Years. Really strange…

Anyway, any chance one of you guys know the thread (pitch) and length of these bolts so I can get them?

Seems like they are quite the important bit in holding the transmission in place right?
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They are M10 x 1.25 thread and bout 1.5" long.
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Going to pull the gas tank out this week. All jacked up and ready to go. Probably need to pull the wheels too.

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Got the tank pulled- kind of a pain in the azz. For whatever reason the gas tank when tipped to the right did have a leak, so a new tank was needed regardless of the fuel pump removal.

Thankfully no rust surprises were found on the body!

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Damn- the inside of the tank was nasty! Full pump too! I’ll get everything cleaned up, remove the rust, new pump (understanding I should go right to a Walbro 190 or 255 pump). It’ll work like new when I am done..

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Damn- the inside of the tank was nasty! Full pump too! I’ll get everything cleaned up, remove the rust, new pump (understanding I should go right to a Walbro 255 pump). It’ll work like new when I a, done..

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Wow did your probe run on salt water instead of gas?
The blues, the browns, the oranges it's trippy man.

Do you guys have ethanol in regular grade gas, here 87 octane and 89 octane have up to 10% of that crap in it (ethanol), it is highly corrosive and absorbs water. If you store the probe for the winter make sure the fuel in the tank is ethanol free or drain it.

You should go to a walbro 255 pump if you plan on upgrading performance in the future (beyond the VJ11 turbo), if you run a walbro 255 you will need to run an adjustable fuel pressure regulator to get fuel rail pressure back down to factory settings for idle and cruising.
The easiest way to run an aftermarket fuel pressure regulator is to remove the fuel rail, remove the factory FPR, remove the block nut and washer at the end of the fuel rail (passenger side). You need a 1/4" National pipe thread (npt) tap (male) and a 3/8" NPT tap. The factory fuel pressure regulator hole is the correct size to thread to 1/4"npt (no drilling required) thread the hole and install a 1/4" npt plug (hardware store 2$), the end of the fuel rail you removed the block nut and washer is threaded to 3/8" X who cares thread pitch. it's the same thread pitch as 3/8" NPT but not tapered, thread the end to 3/8" npt and install a 3/8" npt male to 5/16" barbed fitting (Use gas rated teflon tape on the NPT fittings before screwing them in). Get some 5/16" high pressure fuel hose, Run the hose from the barbed fitting to the new FPR and from the FPR to the return pipe the factory fpr connected to.
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Not sure how much ethanol was being used 20 years ago, but there was several gallons of gas in the tank and suspect it was attracting a lot of moisture. Thanks for details on the fuel pump/regulator, I will likely make that a second stage improvement. May just go with OEM spec fuel pump to start (again just to make sure everything works) and then if/when I start adding HP I’ll make these incremental improvements..
The fuel sending unit cleaned up rather nicely over night.
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Well if you are planning to upgrade eventually why waist cash on a factory pump only to replace it, a 255 lph pump and fpr aren't variables that will cause start up issues, you can set fuel pressure before ever starting the engine, just jump the yellow connector on the drivers strut tower, turn the key on, and set the fpr to 40psi fuel rail pressure.
You put on a serious upgrade clutch without requiring it yet.

Speaking of the ACT clutch, I cant tell how thick the pressure plate forks are or if it runs needle bearings, I can tell the disk is unsprung. If when the clutch pedal is pushed to the floor there is a lot of resistance on the pedal, than it's a stage 4 clutch, they are very dangerous to these motors, especially one that's freshly rebuilt.
I recommend, first starting the car and letting it idle for about 20 minutes, dump the oil and filter, put in 20w 50 oil and a new filter (first start up after a rebuild procedure).
Then let the car run for a while without driving it or using the clutch pedal, when driving the car, refrain from holding the clutch to the floor at lights and in traffic, keep an eye on the oil under the valve cover (pull the valve cover and check for sparkly bits with a light). if you find any sparkles in the oil the pressure plate is walking the crank and it's chewing up the thrust bearing, you will need to change the pressure plate it this happens. After a few thousand miles and an oil change you can start using the clutch normally, but if it is a stage 4 ACT they also have a tendency to crack the release bearing arm over the pivot ball in the transmission and the release bearing can cut into the pressure plate forks due to the extreme pressure on the release bearings bearings.
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Ok- ordered up a Walbro 255 kit. Advice on a fuel pressure regulator? Looks to be plenty of them on eBay - some cheaper than others.

The clutch came with the car new in the box- damn I should have kept the packaging- not sure which model it is.

Thanks for advice on the start-up- hoping that will happen on the next 1-2 months. Waiting on parts (fuel pump, modify the fuel rail, buy a fpr and new gas tank).

I pulled the muffler off and separated all the exhaust pieces to I can clean them up- The exhaust is a 2-1/2” system from the cat (which appears to be missing) back. Not sure what brand this exhaust is, but expect the picture below should help someone in here identify- especially with the yellow stripe on the chrome exhaust tip..

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The exhaust is a pace setter.

Got any other pics of the pressure plate that you didn't post?
there is a serial number pressed into the housing, also you can zoom in on the pressure plate forks and get an idea of which pressure plate you have.
These are current listed pressure plates part number and pictures, older pressure plates have different part numbers and flat forks on the diaphragm.

My ACT clutch dissertation:

Heavy duty pressure plate, MZ010
Torque capacity 420 ft/lbs
Light to moderate pedal effort, aggressive engagement, increased gear rattle
Moderate friction life, extended by ACT's exclusive diaphragm design, rigid design may increase spline wear

Xtreme pressure plate, MZ010X
Torque capacity 560 ft/lbs
Moderate to heavy pedal effort, aggressive engagement, increased gear rattle
Moderate friction life, extended by ACT's exclusive diaphragm design, rigid design may increase spline wear

MaXX Xtreme pressure plate, MZ010XX
Torque capacity 625 ft/lbs
Heavy to very heavy pedal effort, aggressive engagement, quicker shifts, increased gear rattle
Moderate friction life, extended by ACT's exclusive diaphragm design, rigid design may increase spline wear

(Torque capacity's are with 4 or 6 puck sprung and rigid disc's)

Heavy duty:


MaXX Xtreme :

Release bearing fork crack:

Release bearing wear on pressure plate forks:

You can see these are really thick forks, so the most aggressive ACT pressure plate.

An mx6 GT I bought came with a brand new ACT clutch, unsprung 6 puck and nightmare pressure plate, I installed it in my 89mx6GT.
First the ACT walked the crank on a freshly rebuilt block(new factory bearings and rings and honing), everything was mint but I changed it anyway.
Installed another factory cleaned and honed block (broken in the F2T crank can handle the pressure plate) , after 6 months the release fork cracked, I adjusted the clutch pedal but after a week I couldn't disengage the clutch so I pulled the transmission and changed the fork.
5 or 6 months later I was having trouble disengaging the clutch, checked the release fork, it wasn't cracked so I though the crank was walking again until I puled the rubber vent boot off the transmission and looked at the clutch forks. The release bearing was not worn or seized or damaged in any way.

I pulled the clutch out of the car and installed a centerforce stage 2 clutch I had kicking around and dropped the act and a flywheel off at bully clutch.
After the proper breaking in, millage and time the centrforce slipped at 15psi (junk).

Installed a bully stage 4 clutch 6puck unsprung disc and needle bearing pressure plate with 700 ft/lbs torque capacity.
Light pedal engagement, aggressive/instant but controllable engagement (due to light pedal effort), fastest shifting (due to light pedal effort), no increased gear rattle (due to light pedal effort), reduced wear and tear on components (due to light pedal effort).

The pressure plate is very heavy and extremely thick but the needle bearing diaphragm makes it very easy to disengage and once the forks are flipped (pedal to the floor) the pressure plate offers no resistance (Pedal doesn't push against your foot).

My ACT clutch's MaXX Xtreme Effort pressure plate review:
When not destroying the engine or itself the ACT stage 4 6puck unsprung clutch disc and Mr. Universe pressure plate lock the crank to the transmission and don't slip at all while offering your left leg the workout of a life time.
If you think the clutch pedal is hard to get to the floor (you will be giving the drivers seat and steering wheel a strength test) wait until you try and hold it to the floor, the Aneurysm Detecting pressure plate is designed to increase resistance with pedal travel and offers the most resistance at full pedal travel giving you the best possible work out, you will feel the burn.
If you got impatient waiting at long red lights the Maxx Xtreme Leg Cramp pressure plate will make holding the pedal down for 30 seconds feel like a lifetime. This ACT Torture Device doubles as a security system, you can leave the key in the ignition and the doors unlocked, no one else can drive the car, most can't get the pedal to the floor, those who can will stall the car, your friends will only ask to drive your car once and never bother you again.
As well as giving your left leg the most challenging physical work out of it's life, the ACT clutch's Will Fight You Every Step Of The Way pressure plate also works out your whole body while offering you the opportunity to practice and improve or hone your engine swapping and transmission removal skills.
Eat your Wheaties and enjoy your Advanced Clutch Technology Medieval pressure plate.

My tips for Operation:
The position of the steering wheel and drivers seat are key to the operation of ACT clutch's Atlas workout* Pressure plate, the seat should be close to the steering wheel to offer the best leverage point, braise your entire body to the seat and position your foot over the pedal, as you start pushing on the clutch pedal pull on the steering wheel to avoid braking the seat back or ripping it from the floor, avoid pulling too hard on the steering wheel to avoid bending the wheel or ripping it from the column, a careful balance of pressure to the seat and pull on the steering wheel is required to get the pedal to the floor from a seated position. Roughly 150 lbs force on the pedal is required to get the ACT Why Is My Leg Shacking pressure plate to disengage the clutch disc.
It is recommended to position the steering column so once the clutch pedal is pressed to the floor your left knee can be braced under the steering column bezel while waiting at the tree, start line or red light. ACT's Luke Crank Walker brings you an hour workout in seconds.

My only real criticism of the ACT Big Left Leg pressure plate would be that there is so much pressure trying to raise the clutch pedal that attempting to shift under acceleration on bumpy roads can/will kick your foot up and off the pedal causing miss shifts.

*as seen in comic books.

ACT states the Maxx Pain pressure plate and 4 puck rigid disc clutch kit offer the quickest shifts.
I don't know about you but I can get a pedal requiring 28 - 30 lbs pressure through a gear change with a tap of the toes, I had to kick the clutch pedal like it owed me money and try to rip the motherf&*ker from the firewall when running the ACT. I mean the ACT Maxx Xtreme pressure plate might have the fastest engagement because the pedal comes up faster than a human can lift his foot but getting the pedal to the shift point is definitely slower for all mere mortals that can fit in a Probe, mx6 or 626.

For anyone interested in experiencing an identical simulation to pushing the clutch pedal with a MaXX Xtreme pressure plate, get in your car (manual or automatic) don't start the car, pump the brake pedal once with your left foot, now try to push the brake pedal to the floor.


On a serious note after writing the above I zoomed in on the picture of the pressure plate on the engine, it does not appear to be a MaXX Xtreme pressure plate, so you have 420ft/lbs or 560ft/lbs torque at the crank rating, it should take less effort to operate the clutch pedal and be less of a pain in the ass, it should never crack your release bearing fork.
There are two "types" of pressure plates, those that after the diaphragm forks/splines/fingers move a certain distance needle bearings, pivot bearings or rod or other flip and hold the actual pressure plate away from the clutch disc with minimal effort (pedal has resistance going down but takes no effort to hold to the floor) and pressure plates that you could call "unsprung" the pressure on the diaphragm required to get them all the way to the floor is required to hold them to the floor.
Although this may sound like it's a simple question of more effort, (personally it was cool, stiff clutch pedal, manual rack steering, short throw shifter, stiff brake pedal and soft gas pedal, the car was so much fun to drive the effort was worth it and it all got easy including using the clutch) but the power exerted on the pressure plate from the release bearing and hydraulic clutch assembly which is 6:1 pedal travel to master plunger travel X whatever:1 slave to release bearing travel (usually 2:1), so pressure on the pedal X 6 X 1.5-2 or say 30ft/lbs X 6 X 1.5 = 270 ft/lbs pressure against the pressure plate, that would be a conservative pressure for a factory F2T clutch, if the pressure plate "pivots" when the pedal is to the floor (hold it with a couple fingers) you can calculate how much pressure is at the pressure plate/flywheel when holding the clutch = very little. If the pressure plate dose not pivot and there is 30, 45, 75 or 150 pounds resistance holding the pedal to the floor how much pressure is pushing on the pressure plate/flywheel/crank/ low pressure oil film between the central crank bearing (thrust bearing) and crank to keep the crank centered during idle (low oil pressure) and that is all that is resisting against the clutches pressure.
So load on the crank and release bearing and clutch system are much higher with an unsprung pressure plates when holding the pedal down. Could still walk the crank or wear the pressure plate forks (only slower).

Writing this and thinking about it don't pump the clutch pedal no mater what kind until after the engine has been started and runs a while, especially with rebuilt engines, jump the safety neutral switch at the clutch pedal and start the car in neutral (bleed the clutch after getting the engine running and up to oil pressure). Use the clutch on cars that have been sitting a while as little as possible to start it and let the car and oil warm up with the car in neutral, only gravity bleed hydraulic clutch systems and avoid pumping the clutch pedal with the engine off or running with cold oil. Any time a crank moves without oil pressure it's bearing against crank friction.

I hope you checked the piston ring gap like Juan mentioned on page 1, forged pistons heat and expand faster than cast pistons and cylinders walls, they require being warmed to op temp before every use (idle for warm up).
Also you should find out what bearings your friend had installed in this engine, it will decide your power potential tri- metal bearings deflect and take high boost crank deflection but bi metal bearings don't.
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In looking at each of the pressure plates it appears I have the heavy duty model. Good advice on the first start up..Here is a close-up:

Regarding the piston ring end gaps I didn’t check and to be honest I just didn’t have it in me to pull all the pistons. That being said, I did message my friend who sold me the car and he said the builder back then built the engine for increased HP from a larger turbo and “thinks” he remembers a conversation about the ring gap, but who knows. I may regret not checking/and or increasing them. He doesn’t recall which bearings..

Got the muffler cleaned up and a coat of high temp paint. Also a couple small things cleaned and paint (fuel pump cover along with a new gasket).

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