I got the crank in and it spins fine BUT has zero end play. One stud was a little funny on the thrust cap (interference) when I was doing my pre work on this engine.

I turned the shank down .005" by hand but still causes the main cap to flex and cause interference with the crank. My friend was over and he is going to take it to his tool and die shop to take another .010" off of the shank.

I tried the same main cap with the factory bolt and the crank has .005" end play. Well within the .002-.007" spec.

My guess is when the block was originally machined by the factory they were off a little but because the factory bolts have a much narrower shank it did not interfere with the cap.

Left alone, this probably would have been a spun main bearing.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

Hmmmmm

_________________
10.74 @ 127.47 mph 1320 ft
6.65 @ 107.80 mph 660 ft

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Good to know. How much HP are you trying to make? Stock bolts would probably be fine, IMHO... I have 1/2" main studs on my new Project V motor, installed by the guy who gave me the block, and I'm not sure I'd have bothered. No clearance issues in my case. Seems maybe the cap was distorted somehow??

Lou

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Home of Slant6-powered fun machines since 1988

Lou, I really don't know how much power to expect but I figure the stock motor is currently making somewhere around 350-370hp (crank).

The new engine will have the advantage of a fully ported head with big valves & camshaft. Say 450 to 550hp at the crank? I really don't know what to expect.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

Great. OK, I would probably do studs too. 500HP seems doable.

I will be shooting for 300 HP on 6-8psi with stock short block and a good head/cam (street car, pump gas), then move up in boost from there.

Lou

_________________
Home of Slant6-powered fun machines since 1988

Very doable!!

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

Check the hole thru the main cap... sometimes those are a little "cock-eyed", end to end.
The last time I had this problem, I used my die grander on the offending edges of the main cap holes so the stud did not make contact.
Be sure to "align the faces" of that thrust bearing.
Basically, get the cap on and lightly snug, then tap the crank forward and back, to align the thrust bearing surfaces on the top and bottom bearing shells. I alway end the alignment process with a tap in the rearward direction, because the front surface of the thrust sees the most contact.
DD

Thanks Doc. Will do if the extra material off of the stud does not clear up the problem.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

Aren't you really supposed to get the block align honed if you use main studs?

I honestly don't know for sure, but have been told you should.

My junk don't make enough power to break stock bolts anyway.

_________________
Official Cookie and Mater Tormentor.

I had the line checked with the studs and it checked ok. The issue seems to be with the fore and aft assoeciated with the thrust. Not sure if a line hone would have corrected this.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

I dont think that an align hone would have corrected the problem your having.
Frank

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Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

We decided to hone the cap as the stud may only be case hardened. Need to order 1 stud.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc