Oil pump install with ARP main bolt?

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dgully

dgully

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I used ARP main stud bolts and when installing the oil pump the pump hits the bolt leaving about 1/8 inch gap. Should I start grinding? And I really don't want to pull the bolt and remove the washer.

Any ideas?

Thank you
 
When I ran ARP bolts I ran a factory bolt under the pump.
 
Do think iam OK with un- torquing it and installing the factory bolt?
 
Also if the ARP is torqued to 100 what does the factory bolt torque too?
 
If you call ARP they will probably send you a bolt that can be used. One with a short head that will torque the same as your studs. They've done it for me a few times. I don't know why they don't offer a kit that addresses the issue. Every time I call they tell me it's the first they have heard of it but then offer to send a bolt that is their solution to the problem.
 
grimreaper said:
If you call ARP they will probably send you a bolt that can be used. One with a short head that will torque the same as your studs. They've done it for me a few times. I don't know why they don't offer a kit that addresses the issue. Every time I call they tell me it's the first they have heard of it but then offer to send a bolt that is their solution to the problem.
Click to expand...

Funny how they have never heard of it, but have the fix available right off the shelf....
 
Why not get a grade 8 bolt and washer that will work at a local hardware store??? 3/8" x 16 x 1 1/4"

Torque it to factory specs... 30 ft*lb
 
krazykuda said:
Funny how they have never heard of it, but have the fix available right off the shelf....
Click to expand...

They have Heard about it for all three of my engines...and sent me a bolt all three times.
 
OK just called ARP and must have been a new guy, said he's never heard of this on a small block only big block but I have a bolt that should work. Lol. So he's sending one out that "might work"
 
Yeah, they literally field this question every time someone goes to install their stud kit on a SB Mopar...so i'm guessing that their bolt that "might fit" is going to be just fine.lol
 
I took my main cap and had it shaved down .100 on the landing for the nut and cut the stud with a hack saw flush with the top of the nut. I then removed a small amount of material from the pump. That gave me enough clearance.

I spent good money on a set of studs, i'm not sacrificing the integrity of the stud setup by using a single bolt with the studs. I know many have done it this way, but I wouldn't be able to sleep at night knowing that bolt is in there.
 
ARP isn't immune.

Same as tti telling me 3-4 times that it was the first time they ever heard about Z bar interference with SB A body headers. :)

You'd figure they might take the time to engineer a solution that doesn't require mailing out a bolt, OR, just put the dang bolt in the stud kit!
 
Mine are all bolts and not studs so the bolt has a lower profile hasn't weakened anything. Same size bolts just one has a low profile head?
Or did I read the last post wrong
 
Dgully,

I think we all assumed you were running a Stud kit. But nonetheless, you're still not "sacrificing integrity" by using the lower profile bolt they send you.

nor would you be sacrificing anything if you replaced one ARP stud, with one ARP bolt for clearance issues.
 
That's what I was thinking also. I have both ARP bolt and stud kit and for no reason at all I decided to go with the bolts. Is one better then the other? Why? Just curious and maybe I'll swap over to the studs....
 
I cut the stud down and use a 12pt nut on it. As long as the pump sits flush to the cap, and the nut has full thread engagement on the stud, you're good. I'm not a big fan of using one bolt with studs, but others have done it without issue.
 
dgully said:
That's what I was thinking also. I have both ARP bolt and stud kit and for no reason at all I decided to go with the bolts. Is one better then the other? Why? Just curious and maybe I'll swap over to the studs....
Click to expand...

The whole argument of studs vs bolts comes down to torsional loading, and bolt stretch.

In super simple terms...When you torque down a bolt, you are twisting the bolt, AND stretching the threads. This adds a margin of error to torque specs.

On a stud...you are only dealing with the stretch, and the rotation of the "bolt" is non existant, since the stud is staying stationary.

this being said...studs can be thought of as "better" but...it's really irrelevant in most instances.

my 7000 RPM, 650 horse, 408, has all studs..and one lonely ARP bolt that (they had to airmail me) under the oil pump. Am i Thrilled with that?..ehh.. not especially.
Do i think it's the lesser evil than grinding on everything, and running my main cap through a heat cycle to "shave" the landing area...Yes.

To each his own. The typical "do i need a return line?" "edelbrock vs holley" "takeout my thermostat?" style argument.
 
Thank JohnnyMac, that makes sense now. This is my first 340-416 stroker build, so iam learning as I go. Thanks for everyone's input
 
grimreaper said:
If you call ARP they will probably send you a bolt that can be used. One with a short head that will torque the same as your studs. They've done it for me a few times. I don't know why they don't offer a kit that addresses the issue. Every time I call they tell me it's the first they have heard of it but then offer to send a bolt that is their solution to the problem.
Click to expand...

Exact same line I got.
 
As for my decision - All my engines get align honed. Once a cao is torqued with a stud, the cap deforms differently from a bolt because as Johnny said - they clamp differently. Then the bore is honed to size. When you loosen the fastener, the cap and block distort. If you don't use the same fastener to put it together as what it was machined with, when you do bolt it back together it is very possible the bore will not be the right shape or dimension. So I just found a way to make the same stud work. No cutting on the cap or heavy clearancing on the pump body. It will be a problem on mains 1 through 4, but 5 is a lot thicker and has more contact area witht he block. So it's possible it fine. I've never checked myself....lol.
 
Is this issue all ARP main stud kits or only the 6 point kits? I have the 12 point kit on mine. Ill probably have to cut the stud though which is no problem.
 
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