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ARP head bolts shorter than oem

Phoenix440

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I am installing reco iron heads on a 440.
Decided to guy ARP bolts, Felpro marine gasket, trying to avoid the previous leaks that were in the motor.
Was about to install one of the heads and thought it might be a good idea to make sure the bolt lengths are correct.
The long centre bolts with washer installed are exactly the same length from bolt tip to under the head ( washers installed on ARP).
The short ARP bolts with washers installed are a bit over 3/16 shorter than oem ( so this much less thread engages in the block).
The kit is AR145-3606 which is standard replacement.
Anyone ever struck this and want are people's opinions on this? Will the less thread cause any issues with clamping force ?
I have contacted ARP, havnt heard back, but just wondering if anyone has seen this or did they mix up the bolts?
Any ideas are appreciated
 
I have had ARP bolts that are the other way: too long [ & too short ]. You have to double check ARP stuff, their QC is terrible..if it exists at all.
Nothing wrong with the factory bolts.
 
I have a set of ARP bolts that were on a 1990 360 that I bought from a friend. Those were shorter than factory head bolts by a good 3/16".
Not good.
 
As long as your threads are engaged, you should be alright. If this was airplane stuff, they like 3 threads showing. My Hemi has about 1 thread showing with Edelbrock heads.
 
No, you want as many threads as possible engaged, especially cyl heads & main brg cap bolts. Head bolts can distort the cyl bore when tightened. You want as many threads as possible to reduce distortion. For this reason, one of the benefits of studs over bolts is more thread engagement.
 
You won't have any problems. If you are concerned with the shorter bolts, don't use the washers. The ARP bolts already have a flanged head, so they will work fine as is. When using main studs, and there was not enough thread above the nut, ARP said to just eliminate the washer, and everything worked out fine.
 
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