3.8 crank in a ordinary 4.1 ? any real reason why NOT?

**bbatka** · 03-29-2011, 08:42 AM

My first question is:
I'm building a N/A 252- the original 252 crank is already .020 under and now has slight grooves in the mains. So I'm afraid to have it ground any more. I have a fresh .010 under 231 crank. I know the filleted crank of the 252 is stronger, but is it necessary in a stock 252?? Is there any devastating reasons why I cant use the 231 crank in my 4.1??

Second question: I'm considering the comp 206/206 roller cam (for a little pep and so I won't always need ZDDP). Will that be too much for the stock 231 crank in my 252?

thanx, brad

**sean buick 76** · 03-29-2011, 03:57 PM

From what I know the 3.8 crank should work since the stroke is the same as the 4.1. There could be other changes though.

The roller cam is a good idea, I would not worry about the block as it should be safe to about 900 hp. Just remember that there are a few other things to go with the roller cam like a button for the front cover.

**sean buick 76** · 03-29-2011, 04:00 PM

I would not worry about grinding the crank more than 20 thou as there are people who have offset ground Buick 350 cranks and make 600 hp withut issue.

**BigRivy** · 03-29-2011, 10:41 PM

Undersized crank will not be a problem. Using the 3.8 crank will not be a problem. Switching that motor over to a roller cam is gonna be a lot harder on your wallet than it's gonna be on that crank. Adding a little oil additive every once in a while would be a lot cheaper.

**bbatka** · 03-30-2011, 10:18 AM

I got a deal on a never-used (old stock) comp cams 206/206 roller cam and lifters (well under the current price) some years back. So I figure its about time to use them! The heads are at the machine shop as I write this, getting prepped for the additional lift and new springs.

Where can I find a nylon/teflon cam button for this cam? I was told NOT to use the stock spring button- especially with a roller cam. I'm gonna look thru ebay, but any advice is always welcome!!

**sean buick 76** · 03-30-2011, 04:41 PM

Originally Posted by bbatka

I got a deal on a never-used (old stock) comp cams 206/206 roller cam and lifters (well under the current price) some years back. So I figure its about time to use them! The heads are at the machine shop as I write this, getting prepped for the additional lift and new springs.

Where can I find a nylon/teflon cam button for this cam? I was told NOT to use the stock spring button- especially with a roller cam. I'm gonna look thru ebay, but any advice is always welcome!!

I would call Ta performance.