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Discussion Starter · #1 ·
Has anybody here experimented with offset grinding their crank rod journals to increase stroke and static CR?
Just wondering...
Q
 

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This has been done to a number of cranks and will continue to be done. I would not suggest such a change. I think it would be much easier for you to get a stroker carnk and go that way in stead of spending the money on a modified unit. The crank will not be as strong as a forged unit in my opinion.
anyway that are just my thoughts on the matter.
 

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How about for Decreasing Displacement?

We just had an L-20 crank offset-ground to DECREASE the displacement of the engine! The bores on the used engine (we call that a "seasoned block... Yeah, set it out in the rain for a few 'seasons' and you get rust in the bores!) were rust-pitted, and had to have a .020 bore to clean them up. So to keep within our displacement class (2000cc's max displacement) and considering the stock motor is 1998cc's, we offset ground the carnk to give us some measurement error for classifying the engine. Nothing worse than breaking a record and then having it disallowed because the engine didn't tech-out to the correct specs!
It's used in that way much more commonly. Except in the case of Small Block Chevys in the 350-383 world. Then you use the small journal rods, and offset grind the crank for the stroke you want... But with the availablity of stroker cranks, it's pretty much relegated to small displacement 'fudges" to keep within a class, and not much else.
****, you could get a 3.5 liter kit in Japan in the late 80's early 90's, why bother with cc's when you could add 20% in one big jump?

Crower made the crankshaft, BTW...
 

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Building a stroker motor is fairly bolt together but requires many parts that are not stock on a L-28 motor. Just stroking a motor will not greatly improve it's performance. But with the rods crank and piston combo you can build a stump puller, mated to the well build value train and you have a real weekend warrior car. The cranks are not that common and may require some searching. As for the headache of offesting the journals, many say they would not run such an animal due to the diminished strength. I know that it has been done and very successful but the cost vs. stroker crank availability, I would open the phone book and look for the closest junk yard.
 

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I have one,

I purchased an L28 crank that had been welded and then offset ground to increase stroke. It has an 84mm stroke as opposed to the 83mm stroke of the LD28. It was also double Nitride hardened kind of like 'twice baked potatoes.' I often wondered why they called it that as if they messed up the 1st time and had to do it again! Anyway, I have this crank because the guy sold it to me for cheap, $350. I would think the only problem would be finding someone you can trust to do the work.
 

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Discussion Starter · #6 ·
Crower crank kits

Turns out they still make them. Forged cranks, rods, and pistons, all for the bargain-basement price of $5500! For that kind of cash I'd toss a Lexus V-8 in this thing and call it done.
 

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Now you're talkin!

At some point, common sense takes over and says "If I'm going to stroke it to only 3.5, then why not get a V8?"
My limit is 3.0 liters, the rest is boost. After that, it's easier to go Chevy...
 
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