Burgundy 69

Looking for info/advice regarding converting a 3970010 2-bolt block to a 4-bolt block. I seem to recall reading at one time that this was not a bad idea. Any thoughts? Thanks.

Mark

Fevre

No need to unless you think you will punish more than this 2 bolt with all stock lower end:

http://www.chevyhiperformance.com/te.../148_0303_n20/

TedH

Save the cost of the 4-bolt conversion and instead put it in good fasteners (ARP) and other quality engine parts. Unless you are making over 500hp and planning to punish the engine regularly (1/4 mile), I'd stay with 2-bolt.

gkull

If you plan on using a really hard forged crank like 4340 you need a four bolt and it's preferrable to use a studded bottom end. The harder the steel the easier they break if the main caps have any movement. That's why lessor forgings like 5140 or even cast cranks have some advantages.

IMO - You just have to justify the cost and have peace of mind in what your doing.

ken markusa

When you add up the cost of parts and labour it would probbably cheaper to just get a 4-bolt block.
Ken :cheers:

Twin_Turbo

if you want to convert to 4 bolt, IMO don't waste the money and get a splayed 4 setup. It's a little more costly but if you are aiming for more revs & power in the longer run you could regret going to a normal 4 bolt setup.