LT1 POWR

Should i use a 93-97 LT1 block or an older SBC block for my procharged 383 build? Are there really any differences or advantages/disadvantages? I'm using reverse cooling converted SBC heads and a Vic Jr single plane. I'm still not certain on a EMU(will probably use the stock pcm since its cost effective and I won't be spinning past 6800rpm) and ignition yet, I'd like to get away from the opti and its "problems" if possible. Also what does the machine work on a 383 cost if I supply all the parts or even install everything myself?

rskrause

As far as the block itself, the castings are essentially the same as far as strength, etc. But if you plan to use the OEM ECU, it's easier to use the LT1 block and keep the Opti. The Opti isn't so bad, you just have to replace them once in a while.

Rich

marshall93z

270,000+ miles on mine!

Zaknafein

You, dear sir, are the exception rather than the rule.

I got a little better than 100k out of my first Opti..... not bad by any standard.

FastZ8

im doing a 383 turbo car right now and the opti is definatly going out the window. ive had nothing but problems with it and life would be much easier wothout it.. lol!

MachinistOne

The cylinder walls on the late model blocks are very thin - I would consider a different block if you want to push heavy PSI.