Rebuilding an NA block for my 951(157k--some at 25lbs. of boost which did her in)--I think that the crankshafts are the same but can someone please confirm?

Also, anything I should watch out for? It is an 87 block and does have the port for the oil to the turbo. Oil pump the same?

Many thanks,,

Cyrus

 

Same.

Get the NA - it will have been less stressed.

 

You would need to tap the upper balance shaft cover for the oil feed line for the turbocharger.

 

The main differences are the pistons, rods, head, oil filter console, left engine support, oil separator, flywheel. Oil pump and crankshaft are interchangable.

 

Thanks Guys---the 87 NA already has the oil port

 

Use a N/A crank, they do see a lot less stress than their turbo counterparts, and are exactly the same part. I am using a N/A crank for my spare 951 motor build. Then again, I'm also using N/A pistons.....

Anyhoo, all year's oil pumps are the same, no worries there, since it's an 87, watch out for the tensioner mountings. Probably best to just go back to the manual tensioners from the pre-87 cars (pre-spring, and pre-hydraulic tensioners).

 

Euro or standard n/a? I suppose one could use either as long as a close eye is kept on the tuning. Honda guys routinely boost 11:1 or 12:1 engines without problems - the 10+-ish:1 Euro pistons should be fine as long as you don't knock.

 

Haha, yeah, but honda guys only run 6-7psi of boost. I plan to run the full 12psi stock boost, with an EBC though, so I can push it a little bit higher.
I don't really care if I get euro or ROW N/A pistons, early or late, I will work with whatever I can get. Hosrom has a darn good price on some new over-size N/A pistons, as long as they aren't 16V, then I'll be buying a set from him, since I need to bore out the cylinders a tiny bit on my donor block. I always like to start from 0 miles on a rebuild. It's going to haul *** when I'm done. If I can get the 10.2:1CR pistons, at 12psi of boost it should be maybe 280-290hp?... It will have a very nice torque curve anyways, plus it will be just as streetable as a N/A with all the get up and go (and then some more) of a stock 951

I guess that's a little off topic though

 

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We are talking about the '87 N/A he is using.