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Discussion Starter #161
Yes, that's the one I have.

I'm having a hell of a time finding oversized 5MGE pistons. Does anyone know of any manufacturers? I'm finding plenty of oversized 7MGE pistons but not sure where that would put my compression. I think my current concoction has CR somewhere in the mid 10's. If a complete 7MGE rotating assembly in a 5MGE had compression in the high 8's, then I suppose that would be ideal for a project I've been considering.

Any experts still around here that would know?
 

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I have a set of 20 over 5m pistons brand new in the box. I found a set of the 8.8 5m pistons with rings. They would make 9.2:1 compression on your setup, which is better for boost than the domed pistons would be. PM'ing you the link. They are 20 over.
 

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I've seen several 7MGTE rebuilds using only ARP studs on the stock HG. They say it holds "low boost", but I suppose that's subjective. Not saying its a good idea. Just that it's been done. At any rate, I ordered a new HKS gasket because I dont trust my judgement either.
Yeah I have a bottom end from a guy who went that route. He managed to blow the gasket out of 5 of 6 cylinders and flooded the entire block with coolant. It's a time bomb. I know people who have gotten some years out of that combo, but it always goes eventually, spectacularly sometimes.
 

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Discussion Starter #165
Methinks they get brave and turn the boost up once they retorque with those pretty new bolts. I guess there's a reason almost every 7M swap needs a rebuild before installing.
 

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Discussion Starter #166
Had a couple hours to break the head down today.

I had the head rebuilt at a local shop that's since gone out of business. I wanted to ask the tech what this ring is on the number 1 intake valve spring seat. It wasn't there when I disassembled it years ago. Is it a shim? If so, I've never seen a valve spring shimmed and would have to wonder why he'd put one there.
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All other valve spring seats were normal.
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I think some lapping may be in order.

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Hey, now, I dont remember breaking this one :unsure:
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Looks like they used a random piece of metal as a replacement for the factory spring seat. There is supposed to be a stamped washer under each valve spring.
 

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Discussion Starter #168
Looks like they used a random piece of metal as a replacement for the factory spring seat. There is supposed to be a stamped washer under each valve spring.

I dont recall anything being between the springs and reliefs(?) when I broke the head down for the first time. It only had about 150k miles on it at the time so I'm pretty sure it was the first time the valve train had been disassembled.

Then again, there's all kinds of stuff I'm coming across that I dont remember doing. Knowing myself back then, I wouldn't be surprised to find out I discarded them because i didn't understand their purpose (which, of course, would have meant they had no purpose).

Sounds like I'll have to find some. When I built the 2ZZ in my corolla last year, that was the first time I'd come across such a part. Any other head I've ever tinkered with had valve springs that make direct contact with the cutouts/reliefs. I figured Yamaha put them in the 2ZZ head to help alleviate the stress on both surfaces caused by rotation of the springs at high engine speeds. But now that I'm enlightened, who knows how many vital engine components I've tossed 🤷‍♂️

Oh, well. I sure hope this build goes better now that I dont know everything.
 

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I think pretty much every aluminum head has a variation of them to protect the head itself..
 
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Discussion Starter #170
Copy that. Is it called valve spring seat? Locator? Either I suck at searching or they dont make them anymore. Maybe both.

I can't help but think that any washer with the same thickness that fits in the relief would suffice.
 

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Toyota calls it "Seat, Valve spring" p/n 13734-43010. They look just like this;

 
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Discussion Starter #172
Nice!
Everything is sold out or discontinued. No surprise there. But at least I have the dimensions so I can get some regular steel washers now. I'm glad some OGs are still around to help the rookies 👍
 
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