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Old 10-04-2010, 07:54 PM   #1
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Default what would you do?

i figured this would be a good discussion to have here, as there are many more people here who truly abuse their turbo bp's compared to the fwd crowd.

i cooked my motor recently. damage = i melted the edge of the piston near the valve reliefs in cyl 4. i can see the top ring with my buddies borescope :(. i'm thinking this was probably caused by one injector being a little down on flow... we'll see

i can do one of three things:
1. rebuild motor with forged pistons. its still running fine otherwise, no knocking and it doesnt even smoke. hell it still runs low 12's. i figure this would be pretty straightforward, however it would probably cost just as much as my other options. i dont "know anyone" who can do machine work or assembly work like this.

2. replace with a built BP long block. my friend is selling his built BP but he used a small nose crank engine :(. i could buy his motor, swap out the crank and oil pump, and drop it in. the motor has generic h-beams, wiseco 8.5:1 pistons, arp head/main studs, OEM mazda bearings, etc. solid motor and should take whatever i can throw at it.

3. replace with another GTR engine. if you don't know what the GTR is please click here for some info. for the same price as #2 i can get a complete (used) GTR engine from another friend. it will come with the turbo, manifolds, everything. if i dont screw up my damn settings again it should last a long time. plus, i can sell some spares to recoup some money since i already have 2 spare turbos, and who keeps spare manifolds?

what would you do, mt.net?

Last edited by therieldeal; 10-07-2010 at 02:15 AM.
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Old 10-05-2010, 09:57 AM   #2
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I guess that would depend on your budget and how long you are willing to wait.

Myself, I would go ahead and rebuild the motor with forged pistons, and perhaps do a few upgrades. I prefer to build the motor myself, but I have learned to stick with a machinist that is familiar with the BP even if I have to ship parts or drive a long way.

Options number 2 and 3 would keep me from sleeping well. Everytime I buy something used, the condition of parts are never exactly what I expected.
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Old 10-05-2010, 12:32 PM   #3
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more notes:

1. the current engine may also need serious head work or even a new head, i wont know until i pull the head. i need to keep the car running as long as possible as I live in an apartment and don't own a trailer etc. through the borescope my pistons look just like Savington's supertechs, just not quite as extreme (the top ring is still in one piece, and I still have some compression).

2. The guy selling the motor is a friend whos also a machinist/fabricator/BP guy. He also built an awesome stainless steel downpipe for my car. He built this BP to run a big t3/t4 in his escort, but ended up selling the complete car just after break-in. The guy who bought the car parted it out, and my friend wound up buying the motor back to save it for a future project. If not for the small nose crank, I'd probably be going this route 100%.

3. I have had great luck with my GTR motor which was also a used import (well, until now but that’s likely my fault as I said above). I've been beating the crap out of it on the street and drag strip for several years now, and it has outlived several different drivetrain setups. Its true that you never know what you're getting, but this motor is very clean and clearly from a low-mileage vehicle. No signs of mods, the stock boost solenoid and vacuum hoses are all still in place.

Decisions, decisions....
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Old 10-05-2010, 12:39 PM   #4
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I'm thinking I might go with #3 for now, then I can rebuild my old engine at my leisure to exactly what I want. If this motor lasts even half as long as the first one, that should be plenty of time to save up and build one hell of a motor...
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