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Discussion Starter #1
I am going to be replacing the head gasket in a newly turboed 82 Supra with the stock 5MGE. If I'm going through the trouble, should I upgrade the block to the 7MGTE. I know where a block is, probably cost me $60 for the core plus machine shop work. I thought someone had mentioned that this would be the ultimate combination. If so, what are the suggestions for the build up? Bore, pistons, rings, bearings, head work. I'm on a budget cause my wife is watching the $'s.
 

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If your not aiming for crazy hp numbers a stock spec 7mgte bottom should be good for at least 300 reliable hp. Thats the beauty of doing this frakensteing conversion, toyota already provided all of the built parts you need.

Unless 7m pistons aren't forged, but I'm pretty sure they are.
 

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Discussion Starter #3
Suprafriend

No, I'm not looking for crazy HP numbers. I have a '70' Cuda for that (also a pilot, hence the login). 300-325 streetable horses would be great on the street in an 82 Supra.
 

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7m pistons are not forged stock :( Trust me,I have a few melted one's in the shop :roll: Still good for 300+hp though,with the correct engine management.
 

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Don't forget that combo makes the engine an interference engine.
 

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oh yeah should have mentioned that. If you go with the 7m bottom, pick up some custom forged pistons that have appropriate recesses for the 2 valve heads . Theres lots of people who have gotten them here, they aren't THAT expensive. But that should really be all you need to upgrade on a 7m bottom. Just get a good hg and refresh it and you should have a sweet turbo platform.
 

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If you're going to the effort of putting in a 7m block + getting forged pistons etc, why would you not do it the *right* way and put in the whole 7m-gte? At least that way you get a better flowing head, plus all the electronics that were designed around a turbo.

Just my $0.02
 

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because putting in a block is EASY.

rewiring the whole front half of your car is NOT.

:) just my 2 cents
 

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I know it's easier. But wiring up a 7m isn't all that hard, you don't have to rewire the whole front of the car.

And anyway, the easier solution is not always the better one. I remember Mike Lewitz(from the mk2 list) had all sorts of issues with his. And I don't think he was aiming for heaps of power out of it either.

Not saying it's a stupid idea, it has obviously been proven to work. There just seems to be much better ways of doing things. :confused:
 

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Discussion Starter #10
The reason for not dropping in the entire 7mgte engine is that the head and manifolds have already been stripped from this car. Because I already have the turbo setup, and the head and intake from the 5mge, I was just figuring if it was worth the effort to drop in the 7 block.

I'm also trying to do this car on a budget. I currently have $2300 into the '82', and that includes purchase, turbo setup, and fresh paint job. I'm doing everything myself except for paint.
 

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also some might argue that the 5m head will be stronger with its bigger valves and flow better for boost.
 

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flygfsh1 said:
The reason for not dropping in the entire 7mgte engine is that the head and manifolds have already been stripped from this car. Because I already have the turbo setup, and the head and intake from the 5mge, I was just figuring if it was worth the effort to drop in the 7 block.

I'm also trying to do this car on a budget. I currently have $2300 into the '82', and that includes purchase, turbo setup, and fresh paint job. I'm doing everything myself except for paint.
I reckon that you'd probably best to leave the 5m block. Another thing that I just saw on the mk2 mailing list is that the 5m uses a different pulley style to the 7m, V vs ribbed I think. Apparently the 6m has the V style pulleys, so you'd need to track down the appropriate pulley(s) from one of them to match the 5m.

Instead of getting the 7m block I'd say you might want to consider just getting some forged pistons for the 5m block. Having oil squiters isn't going to make a huge difference IMO for lower power outputs.

And good work doing it on a budget, sounds like it'll be a bit of a weapon :twisted:


SupraFiend said:
also some might argue that the 5m head will be stronger with its bigger valves and flow better for boost.

There is that, but I can't see that argument standing up to be honest. There is no way that a 2 valve head will flow better than a 4 valve. A better flowing head at the very least will give you better fuel economy correct? If, assuming that the 2 valve head does indeed flow better than a 4 valve, why do manufacturers even use a 4 valve head? If the 2 valve is better then they should be using that. As well as the fact that is is cheaper and easier to make than a 4 valve head.

The 2 vavles *might* be stronger than a 4 valve head. But I've never heard of a 7m busting it's valves because they were *weak*.

Again, just my $0.02 :D
 
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