4 bolt main BBC conversion?
4 bolt main BBC conversion? I'm building a 700 hp 454 with a forged crank and H-beam rods. My question - is it worth it to convert the block to 4-bolt mains? I'll be turning between 6500-7000 rpm with 10.5:1 compression.
I've heard of people running 700 hp on 2-bolt blocks, but have never actually seen it done.
I've heard of people running 700 hp on 2-bolt blocks, but have never actually seen it done.
I've turned 8500 with a two bolt main 1966 427, stock forged crank, car type rods with ARP bolts.
Sold that engine because the block was worth a lot of money. So then I built a two bolt 468 with a stock cast crank, stock truck rods with ARP bolts. It made more power down low so I had a 6800 rev limiter and it would see 6500 a lot.
Both blocks were fully machined and the rotating assemblies were balanced.
So IMO the conversion isn't worth it.
Sold that engine because the block was worth a lot of money. So then I built a two bolt 468 with a stock cast crank, stock truck rods with ARP bolts. It made more power down low so I had a 6800 rev limiter and it would see 6500 a lot.
Both blocks were fully machined and the rotating assemblies were balanced.
So IMO the conversion isn't worth it.
I've turned 8500 with a two bolt main 1966 427, stock forged crank, car type rods with ARP bolts.
Sold that engine because the block was worth a lot of money. So then I built a two bolt 468 with a stock cast crank, stock truck rods with ARP bolts. It made more power down low so I had a 6800 rev limiter and it would see 6500 a lot.
Both blocks were fully machined and the rotating assemblies were balanced.
So IMO the conversion isn't worth it.
Sold that engine because the block was worth a lot of money. So then I built a two bolt 468 with a stock cast crank, stock truck rods with ARP bolts. It made more power down low so I had a 6800 rev limiter and it would see 6500 a lot.
Both blocks were fully machined and the rotating assemblies were balanced.
So IMO the conversion isn't worth it.
My wifes 489 is a 2 bolt block. She shifts around 6500. has a Ohio 4340 crank and rods. Can go higher, but why? We bracket race and if it is consistent, it does the job without tearing up stuff. Makes about 600 with a small cam. And runs in the 10.70's.
Staging Lane
Joined: Nov 2008
Posts: 57
Likes: 0
if it is going to be forced induction or nos i would do it just to take the bigger hit believe or not i saw a two bolt cap bust in half with a 400 hp DP but NA you should be good have seen alot go past 7000 with stock block.... good balance is key
