Anyone out there using the BM alu Hemi block

[mopardave]

I am about to pull the trigger on a new aluminum Hemi block and have the KB block in my sites. I can get this block for $7400 with just about all the machine work done. I have also been looking at the Bill Mitchell aluminum Hemi block for a bit less money $5800 i believe, but needs a bit more machining before assembly. Anyone out there using the BM block? I would like to know the quality and how its holding up. I have been told it uses smaller main and head studs than the KB block. I will be building a 12:1 572 using one of these blocks. Thanks

[Thermionics]

You need to speak to Todd Marsh. He has experience with both the KB and BM blocks.

http://www.mopartsracing.com/

[rickseeman]

Buy the KB.

[mopardave]

Do the raised cam blocks help with pushrod clearance? What are the pros and cons to raised cam blocks?

[Super_Stock]

KB. I think Tim said the new KB's have a few extra refinements. I like Marsh's 1990's style web page!!!

[mopardave]

Yeah, the KB block can be ordered many different ways and i don't really know what i need for street/strip deal. Tim is trying to sell me a raised cam block with 60mm cam bore and suggests a belt drive on the street. I don't want to buy what i don't really need.

[Thermionics]

KB. I think Tim said the new KB's have a few extra refinements. I like Marsh's 1990's style web page!!!

The new design is much improved over the original that the old KB was selling.
I have one of the older blocks here in my shop, a new style at my machinists.

Are you running a KB block?

Dave, besides cylinder finishing and lifter bore sizing, what work have you been told that the KB and BM blocks require?

[mopardave]

I'm told the BM block needs decked, lifter bore sized/honed, cylinder bores finish honed and cylinder to rod clearance. The KB, just needs cylinder to rod clearance and cylinder bores finish honed. Tim will do this before i receive it. Ready to assemble. The price for the KB is not much more than the BM once machine work is complete. You might save $500 with the BM block once done from what i figured. I will be talking to Tim again in a couple weeks and know the exact cost for the KB. Right now it looks like KB is $7400 plus cylinder to rod clearance and Finish hone cylinders.

[Super_Stock]

Buy the block and the pistons at the same time, have the block finished to suit those pistons. Get any feasible machine work done before you ship it, if a problem shows up, it's better that it is discovered before you have shipped it down under.

[mopardave]

That is my plan. Tim only carries CP pistons thou and i was planning on using a Diamond.

[rebelrouser]

Been using a Bill Miller aluminum wedge block for 10 years, changed displacement three times, blew it up once. Been very dependable, even after the repair from the rod going through the side of it. When I bought it new, had it bored to fit a rotating assemble from an iron block that had cracks, honed the lifter bores myself, and used the deck as it was. I make around 100 passes in a season, car runs 9.70's 138mph 64 Dodge 3,300lbs Before I bought the aluminum block I was freshening my OEM iron block engines about every 3 seasons, and the blocks always had issues with cracks and barreled cylinders, they never blew up, just could not be used again. After 3 seasons with the aluminum block, took it apart and it was like new, best money I ever spent. It blew up because I got greedy and did not replace a set of aluminum rods, they would last one more season right? nope.

[mt-engines]

That is my plan. Tim only carries CP pistons thou and i was planning on using a Diamond.

Whats wrong with CP?

[Thermionics]

That is my plan. Tim only carries CP pistons thou and i was planning on using a Diamond.

Tim is a good guy to deal with. I got a rotating assembly from him a couple years ago. He said his new piston and ring package was good for about 30hp over the street piston he previously used. I assume he is still going 4.502" on the bore.

As for machining, the BM block has bushed lifter bores that have to be finished to size. You won't know on the KB until you have the lifters and check the bores.
The BM tech page says the block has clearance for 4.5" stroke but I'll believe it after I check the one I have ordered. The KB at the machine shop now had to be clearanced for the 4.5"stroke 7.1"x 2.2" journal rod. It also had to be decked to correct an end-to-end difference in deck height. Lifter bores were sized for Morel solid roller lifters.

Good luck with your build, whatever route you take. It should be a lot of fun.

[Super_Stock]

Dave, Tim builds a lot of Hemis and is also developing new parts for them. I wouldn't be worrying about the CP pistons. If they were sub par, he wouldn't be using them. Also if you plan on using Stage 5 rockers, then you better order them now because sometimes they can be a real pain in the ass to get. Make sure the lifter gallery is drilled for oiling, if your going to use it on the street.

[mopardave]

Tim does not like the BM block. CP is the best in my world, its the price i'm sure i will not like. Diamonds are $1000-$1200 a set. CP i have seen for $1500 a set. Still on the fence with the BM block. I'm glad to see it getting good reviews on here thou. Spoke with Todd Marsh about it and he had nothing bad to say about the BM block.