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View single post by edward_davis

Posted: 09-01-2006 12:46 am

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edward_davis

Joined:	07-06-2005
Location:	Eugene, Oregon USA
Posts:	162
Status:	Offline

For the crank, you should be able to measure the stroke length and compare it to the stats for the 2.0 and 2.2. Let's see... The 2.0 has a stroke of ~2.72 inches (~69.2 mm), from the workshop manual. The 2.2 has a stroke of 3.0 inches, based on the tech articles from the JHPS site. That should be easy enough to see with a tape measure. Doesn't seem like a quarter inch would make that much of a difference, but it seems to.

I'm not sure what crank I have in my JH. I'm pretty sure that it's the original (the PO told me, I think, that the bottom end had never been opened on her in 130,000 mi, but I'm not sure I believe that.) I'm going to get a bit of thin dowel and measure the stroke through the spark plug holes to be sure. Since I've only ever driven two JH's, and the other one (the one I didn't buy) had low compression and was waaay out of tune, I don't really have a subjective way to judge my car's relative power output. I do know that the compression was around 125 psi when I tested it, but that won't tell me about the stroke. So, the dowel will tell me: if #1 and #2 are three inches different in depth at TDC, I have the 2.2. If they're 2.72, I have the 2.0. Easy enough.

I am curious about the cams, though. Can you tell the stock cams from the 107 and 104? Also, if the 104 is basically a higher-lift version of the stock cam, can I get there by having my stock cams reground? Would that be cheaper or as effective as getting the cams from Delta or the club store? How much of a low-end torque difference would 107 vs 104 make if I went for the HC pistons?

I know there's been a lot of talk about cams on this board, but I'm just fascinated by the prospect of hopping up my 907. That engine is the reason I bought this car - the only way I'll ever get to own/drive something that exotic on my budget. I mean, 140 bhp from ~122 cubes is cool, and the prospect of 200+ bhp from ~134 cubes is insane! Especially with 30 year old technology....

Thanks, folks, for feeding my engine obsession.

Edward Davis