434 SBC w. 'mystery heads'

[Claus Moeller]

Just swapped my 355 for this 434 sbc!!


Yes that's right. -My old 355 w. roller cam/lifters/sr torquer heads, I got a 400 block w. LUNATI crank/rods/pistons, 'mystery ported aluminum heads.

-What a great swap!!! -I only have to ad rocker arms, and it's ready to go.
-I kept my old milodon 6 quart pan, and checked crank, -A-OK!

-Here's a few pics of my prep work so far..






I have no idea what the heads are, as they have any markings removed..

only clue is 90 60 stamped right under first cylinders springs (90 under exhaust, and 60 under intake springs)

-Any ideas what these mystery heads are??

btw cam is .480 lift, so I'll swap in on old roller cam w. .525 lift and get some roller lifters/shorter pushrods)

ANy help is appreciated.

[PeteLeathersac]

Looks good but if the block is truly a 400, won't you need to crack the heads off and make sure they have the 400 steam holes before you try and run it?.

~ Pete

[Fast67VelleN2O]

With a 434, you have plenty of room to go bigger with the cam. Like 600" lift at around 282 duration @ 050, lose the RPM intake too. I bet it could make 550 on motor alone with a different cam and intake.