What ARP head studs are used with BMP aluminum wedge block with B1 MC heads?

An engine like that is going to be one of those "figure it out" as you go kind of things. Measure, look in the catalog, make a few phone calls. Good luck, hopefully the parts you need actually exist. Sometimes they don't.

Wouldn't you just run standard B1 studs? I got my B1MC studs from Koffel.

That is what I was thinking.

FWIW, I believe you will need studs with about 1" coarse thread (into the block).
16 short studs about 2.75" long
10 long studs about 5.3 to 5.4" long
8 medium studs about 5.1 to 5.2" long

If you run the rocker package with the 5/8 shafts, one pair of rockers on each short shaft per cylinder, the medium studs may hit the underside of the rocker mounting plate. It needs checking.

I have checked two BMP aluminum wedge blocks made this year (2021).
Both have the head bolt/stud holes drilled 1.30" deep. Not the tapped thread depth
Threading a bolt into the hole by hand, just until finger pressure feels the thread start to tighten was 1.14" deep.
So a head stud with 1.0 to 1.1 coarse thread seems about right.

I don't know what lengths this kit has, but ARP says B1 wedge.
Link to ARP

EDIT:
Wow, ARP responded quickly to my queston about the stud lengths in that kit 145-4007


I bought a used set from another racer, and those studs were 2.75", 5.02", and 5.34"
I imagine the 5.0" would work in both "longer" spots, since my head is the same thickness in both.
The 5" will easily clear under the rocker plate of the 5/8 shaft, paired rockers. I est 0.12" clearance. (checked this morning).
My heads are milled to 60cc, so your clearance may vary (including what thickness head gasket you use).

Thanks for the info I really appreciate the help! I do have the ARP 145-4007 stud kit so I should be fine.

I think you will be fine.

Do you have any way to measure the thickness of the B1-MC heads at the bolt holes?
ie, are they 3.60" or 3.70" , etc.

Do you have your BMP aluminum block yet?
Which rockers are you going to run?

I dropped everything off at the machine shop May 1st so I can't measure the heads. I will be using T&D paired rockers also. The shop asked me if the studs (145-4007) that I gave him were correct for a aluminum block thats why I asked the question.

I have arp 145-4007 supplied by koffels for my b1 originals.

you have to be careful with the studs that go under the rocker stand. Typically they are too short for an alum block, however be careful that when getting longer ones, they dont touch the rocker stand.

I am building an engine with B1 original heads, and using those 5/8" shaft rockers (#8013 for B1 original)
The B1-MC use #8027 and a different offset exhaust rocker. Both 5/8 sets use a longer rocker than the one long shaft per head version.

Scott Koffel told me using the 5/8 paired rocker system will require additional pushrod clearancing of the heads.
I am doing a mockup now, and mine definitely needs material removed. Especially the intake holes. Note the intake holes are angled.

What lifters are you using? I assume you are push rod oiling. Mine is a nitrous combo too, was hopeing to race KOS at Norwalk in July but the machine shop said it will be 3 months until its ready.

I am hoping to use Comp 892 lifters. I am making pushrod clearance to use either all centered pushrod seat lifters (892-C) or centered exhausts with offset intakes (892-L, 892-R)

I am checking to oil hole location in the lifters and the bronze bushings in the block to verify it will work. But I have not completed that work.
Since the block comes without cam bearings, I can't slide a cam in right now. And the lifter bores need final sizing (they come "semi-finished").

Can i make a suggestion, helicoil all of your intake bolts. if you don't do it now you will eventually.


Joe