About to put a 7MGTE in my 87' Need Suggestions to Keep it Reliable

[suprarick]

Hey guys,

I bought my 87' Supra with a 7MGTE that has a BH and rod knock. I'm considering posting up a WTB post here for a somewhat "good condition" 7MGTE motor so I can get my car running soon. I would like to enjoy it for a few years with minimal mods (fmic, exhaust, boost controller) without experiencing rod knock or another BH.

What do you experts on here recommend I do right away before I drop the new motor in? I'm assuming I need to take it to a machinist to get a new metal headgasket but anything else? I hear that these motors experience rod knock without even trying, which I'd like to avoid if there are some preventative measures I can take prior to putting the motor in. Perhaps I'm worrying too much!

-P

 

[supraguy@aol]

Keep a 1/2 to 1qt. of oil in the engine, above the full line.
Avoids rodknock from oil starvation during turns, acceleration and braking.
For a low power goal(<350hp), a felpro/oem headgasket is fine, with some ARP's.
While the engine is in the shop, have them resize the rods to reduce the chances of rodknock- it's a cheap shop service.

 

[Maple191]

Throw lots of money at it and hope for the best. If that doesnt work, throw more money at it.

 

[jetjock]

Weld the hood shut...

 

[suprarick]

In all seriousness,

I wonder if I should also replace the rods, pistons, and bearings. I'm a bit of a worry-wart and am probably over-thinking this whole thing. I just want a reliable 300whp 7mgte. I'm assuming headgasket and resurfacing is a must as well as arp head studs. But should I open up the bottom end if I plan to get a motor from someone that knows the motor works fine without bottom end issues?

I just hear so many horror stories with the ancient 7m

 

[Dan_Gyoba]

For reliability:

Don't cheap out, if you're going to do it, do it right. The 7M is a fine motor, plenty strong enough for 300WHP with basic maintenance. Change the oil, and take care of the cooling system, and the 7M can live a long happy life.

If you've got a BHG and rod knock, it kind of depends on how bad the knock is. If the crank is scored, then you need a crank, and probably rods. Fortunately those can be had.

If you don't need to bore, then leave the pistons alone. Stock are plenty good enough. You may want to hone and replace the rings, depending on mileage and wear. If you need to bore, stock replacement is still plenty good enough. I'd also say that stock rods are fine. If you've the money to spare and are willing to warm up the engine before driving, then forged rods and pistons may warrant looking into, but only if you've got spare budget for those power goals.

That said, I've got the forged pistons and shot-peened rods, but though my 'goal' is 300WHP, I know myself well enough to know how easily that could morph into 400, so I'm building the block for 600.

With rod knock, replacing bearings isn't an option, it's what you've got to do. While you're in there, I'd replace piston rings and all of the internal seals that I could as well. The block's got to be stripped down, so get it honed and decked. Might as well get it line-bored, magnafluxed, hot-tanked, and new frost plugs.

Get the valves done, new stem seals and the head decked as well. Put it together with ARP studs, and a good metal head gasket, and you'll know exactly what's under the hood.

once you're there, keep it good with fresh oil and a well maintained cooling system, and it'll run forever, like a Toyota should.

 

[jetjock]

...I just hear so many horror stories with the ancient 7m...

There's nothing wrong with the engine. It was, after all, installed in Toyota's flagship. The most expensive and highest tech car they made at the time. The vast majority of its problems, as well as with the car itself, stem from incompetent owners.

 

[supraguy@aol]

It would be an interesting test;
Create a hood-mounted access cap for everything under the hood- oil cap, dipstick, coolant, washer fluid, brake fluid- and see how long a Supra could go without opening the hood.

Probably a bit longer than allowing the average owner to poke around in there...

 

[suprarick]

thanks guys. I am taking my car to get a used 7mgte motor put in next week. I'm nervous and excited. Since I'm using this new motor and tossing the old, I decided to have my mechanic replace the headgasket with a metal headgasket and put in arp head studs. I'm not sure if it really needs anything else. I can see the future of this car at about 420-460whp, I don't want to push the 7m more than that. Do you think the stock block and good maintenance can hold that kind of power?

 

[Zrain25]

Just make sure he decks the block and head before a mhg or it will be useless.

460 hp is like that in between horse power

550 injectors lexus afm, exhaust, intake, fuel pump, afpr, and wideband and some type of tuner. With a 57 trim will get u almost to 400whp

You put a t4 turbo on the set up and ur hitting 500hp + so it's a in-between horsepower range.

Thant being said a good stock bottom end will handle 450 hp with a safe tune that's the furthest I would push it. Some have goon a little over 500hp but you need a very good tune. Make sure ur head is good to maybe a valve job and some new springs. Comp makes small block springs I believe that work well with out for cheap. I believe there chevy small block intake springs that work

Just do mods little by little. Everyone who I talk to when I say I have a supra there like ohhh it must have like 700hp. Noooo it doesn't and those types of people never been in a 400whp car. 400whp car isn't a slouch for a street car.

 

[terrenceLP]

Hey guys,

What do you experts on here recommend I do right away before I drop the new motor in?

-P

Learn how to work on cars and save yourself time and money.
Don't trust anyone unless you understand for yourself, RIF -

Get ready to go standalone.
Always have a JZ Back Up Plan.
Be incremental with your progressions so you learn about your car up close and personal.

Otherwise get ready to have a money eating toilet.

 

[Maple191]

dont forget to have the timing cover bolted to the block when decking it as well. And if you play on overszing the pistons install the timing belt tensioner adn torque it down to specs. it has a tendincy to pull on the #1 cylinder wall.

 

[Backlash2032]

I really wish I would NOT have listened to my machinest when he said that the bearing clearances would be good enough. I should have line bored it and put in oversize bearings. However, so far it's running fine, I just wish it had a bit more oil pressure...