Let's say I were to find a fairly inexpensive 2.2L turbo block, manifold, and 2.0/2.2/2.5 heads.

I've got the options to either buy a stroker kit or research the correct pistons, rods, & crank. I realize cost and technology are the 2 main factors you consider - exhorbitant and proven, respectively, for the stroker and fairly inexpensive and as good as my own research can find for the separate parts.

With either the stroker or the bits n pieces, what would then be my next step?

Take the block to a reputable (and hopefully knowledgable about boxers) machinist? Then what? Lay in the crank in w/ rods attached, then close the block, drop in the pistons, connect pistons to crank (through that little hole like they showed in the in one of the tuner magazines), tighten block in the sequence that's in the Suby shop manual, fasten the heads, attach manifold and then drop in engine bay?

How far off am I?

How many thousands of little (or big) things did I leave out?

There. I did said it for you.

 

Any response would be appreciated.

 

I am not totally sure how accurate my info will be, but I dont think its too far off. First off...for boring your block....dont take it to just any machinist....you wanna take it to an engine builder/machinist. When boring an engine block, you must be very careful not to bore too much, otherwise the cylinder walls will get too thin and will break apart when then engine is hot and running, thus getting ingested into the engine...needless to say, this is a very bad thing. Also when boring a smaller engine such as a suby motor...installing sleeves into the bore will ensure that the cylinder walls are strong enough.

as far as Stroking the motor....I THINK this is how it works....by stroking an engine, you are making the distance the cylinder travels up and down longer, therefore you will be replacing the stock crank with a stroker crank, and I am not sure if you have to replace the actual cylinders with ones that have a relief machined into them that allows clearance for the heads, since the cylinder will be getting closer to the heads at the top of the bore than it did in stock form, but by doing this you will increase the compression of the motor, so the rest of the parts must be able to withstand the higher compression as well.

I hope this helps....and if anyone sees any misleading information in what I have said, please correct me if I am wrong. Keep in mind this is MY understanding of this and I am not 100% sure of its accuracy. good luck


-Ted

 

Ted,

Thanks very much. Based on replies to this, I was going to divert the thread towards sleaving. My friend Dom, ImprezaRSX, has researched this a bit and is a big fan of the Darton sleaves which he says cost about $85 per sleave and increase the wall strength at least by 2x. It's almost enough incentive to find a cheap, old 1.8 liter. Although, that would sort've defeat the purpose in that you'd still need to fabricate something in order to pop a turbo on top.

 

right on, I have heard good things about the Darton sleeves as well, if you are boring your motor....they are an excellent idea! I hope your quest for parts goes well, and your engine build up is phat! Post up pics when you start to get everything put together, I would like to see your project throughout its stages!



-Ted

 

Wow, there's probably a lot of things that are common to other engines and a few that are unique to the subie flat-four.

I would try to find an engine builder that specializes in subies. They will probably use a deck plate bolted to the block to hone the bores smooth or oversized. Most of the better machines are honing machines and are very precise. The deck plate distorts the cylinders in such a way as to simulate the same forces pulling on the deck and cylinders when the head assemblies are bolted on.

A stroker kit will probably contain the stroker crank and pistons. If it is a non-factory stroke, the custom pistons are necessary to place the slug properly in the cylinder at TDC, set the correct piston pin height, and maintain a practical compression ratio. Any outfit that supplies stroker cranks can tell you where to get the correct pistons for your engine.

It's the specific things I don't know about like the connecting rods. I don't know if you can use factory rods with a stroker kit or if it's advantageous to use aftermarket rods of different length or construction (H-beam rods :drool.

And GotBoost? is correct - sometimes reliefs must be ground at the bottom of the cylinders to clear the crank throws on a stroker. I've seen it done on a Chevy, not on a subie, though.

--
0==WW==0
"…axles of evil…" - george w. bush

 

Dom told me about that deck weighting machining procedures, and why it's important. If I were to get a chance to do it here on Oahu, there is a shop that uses deck weighting, I'll probably be gone by that time, so I'll need to find another shop. Good stuff to know.