944S block the same as NA?
 

Got a good one....

Have a friend with a 944S. Discovered cracked cylinder after doing top end. Is the NA block compatible? What might be the options?

Pretty sure all the blocks are the same. Just different piston crown design and/or height. Might need to swap a sensor or two. The "Turbo" crank might be different but I've never seen anything to substantiate this such as a parts number comparison.

early blocks might have different bearing size and 87+ have auto tensioner for cam belt. But neither issue will matter in using the block with your S head.

The key will be the piston crown if they are cut for valve clearance. The NA pistons would be missing 2 dishes. But if the crown is lower then it wouldn't matter except possibly lower your compression a little (now you can run lower octane gas and save some pennies)

Ok, so far so good. He says he can switch pistons.

The question then is does the early NA block have the mounting holes for the auto tensioner? I have an early block in my '83 NA, but of course don't remember if there are holes there. Would think not.

Thanks again,

Michael.

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AFJuvat

It's a CONSPIRACY!

There is no difference!?!?

I went into this a few months back. I had a S that dropped a valve in the back piston and cracked the block. As you already know, the pistons are different the belt tensioner. The belt tensioner can be fitted on the early block, but the holes will have to be tapped. On trying to find all of the differences, I was also led to believe that there is also a couple of coolant passages that would have to be tapped on the early block.

Well, it appears that the 87 -88 NA block is closer to what will work. Solves the tensioner mount, might be some studs that need to be longer, and the piston swap.

I am thinking I was glad I passed on an S a couple of years ago.

My 83 944 just went to Vegas and back from LaLaLand in the last two days. Outside temps were 105F in Vegas, 109F in Baker, and 70F at the top of the two 4800' climbs each way. Coolant temp never went above half, and the A/C never faltered.

I believe all the cranks are the same as well but I'll have to dig through my emails.

I've heard the auto tensioner can be retrofitted, not sure what that entails.

Basically, it's my understanding that all the 944 blocks can be interchaged with minimal effort with no "special" modifications. Supposedly can be done by the average shade tree mechanic...

gas is ONLY $1.60 for you?!!!!! $2.35 HERE!!!!!!!