2 bolt mains

[SSDan]

I have a 454 with 2 bolt mains. I put a new BDS 8-71 blower on it, and it's underdriven.

The question is...is there anything that can be done to the lower unit that would help support or strengthen the mains short of taking the engine apart and drilling and installing 4 bolt mains.

When I bought the car, most of the work was already done. If I would have built the engine from scratch, I would have started with a 4 bolt block, but I'm stuck with what I have!

New Bolts, Girdle?

Dan

[USAZR1]

A good two bolt block with studs & girdle can handle probably a 1,000hp,Dan. Even without them,your block can probably handle 750hp,safely. BBC blocks are a lot tougher than small blocks.

[cykotic]

I second the stud girdle advice. Modifying a 2 bolt block to 4 bolt mains actually weakens the block. Best to either start with a 4 bolt, or just stud girdle it.

[rocketman]

I wouldn't do anything special,I would either do ARP bolt's or just run it.

A splayed 4-bolt block is stronger than a factory 4 bolt.

I wouldn't worry about a BBC block is quite bit stronger than most think

[Texas Hotrod]

I have heard that stock cast 454 cranks have a weak spot behind the 1st throw area. Is this true? I'm not much of a big block guru yet.
You didn't mension if you had a steel crank or if you installed a crank hub.
I agree w/the stud/girdle combo. It worked for me.

I built a s.b.400 (509 casting) w/a stock bottom-end and I have a 671 on top of it. I studded the mains (and the heads) and used forged pistons. It's a way mild combo and makes a ton of torque. It's been on the street for 6/7 years w/no problems.
Use an MSD btm, and don't ever let it ping and rattle. It'll grenade before you can lift your foot out of it.

Good luck!!!!!