May 24, 2013 update to the Subaru Impreza WRX project car

Busted Upside the Heads

We dropped our heads off at Express Engines and were promptly told they were crap.
Look closely between the spark plug and the top right valve. The crack goes from one to the other.
If you've got a good eye, you can see one here, too. Both heads were scrap.
Our Supertech valves and guides will get to remain in their packaging for a little while longer.

Knowing we had a badly cracked valve and that every exhaust valve leaked—but none of the intake ones did—suggested to us that we had a lean mixture. High temperatures burned our valve seats and cracked one valve pretty badly, so we got a new set of valves from Supertech. Stainless steel intake valves and Inconel exhaust valves should be more durable and handle higher temperatures than the stock valves.

We talked to a Subaru specialist in Orlando, and they recommended that we also replace the valve guides. Apparently these also tend to wear out. We got Supertech’s manganese bronze valve guides to do the job.

And then we took our shiny, new valves and valve guides to our engine shop, Express Engines. We have one guy who’s working on our engine: Fritz. He turned the heads over and immediately saw a bigger problem. One of them is cracked.

So is the other one.

He didn’t recommend welding them. “With something like this, you’ll just keep chasing cracks. It’s not worth it.”

So we began looking for a pair of heads on craigslist, eBay Motors, and all the various Subaru message boards. After finding several cracked heads and a few dodgy ones—someone was actually trying to sell a pair of cracked heads for $200 apiece—someone on NASIOC helped us out with a pair of heads for just over $400, shipped. We sent the payment via Paypal and waited for them to arrive.

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Comments
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jstein77
jstein77 SuperDork
5/24/13 12:29 p.m.

Wow, first the bottom end and now both heads? Might have been cheaper/easier to buy a reman long block? They're about $5K. Then again, hindsight is 20/20.

noddaz
noddaz Dork
5/26/13 7:38 p.m.

Cripes.. At least you have replacements coming. Move along, nothing to see here...

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