Which head bolt kit for 1999 454 Mag MPI ?
Merc showing $130 per side with kit 8M0102366

I just used ARP for my Gen VI 502 MPIs.
ARP-135-3601

I agree and That's over $20 cheaper than the GMPP headbolts (which I think are ARP also).

Clean oil off the bolt threads (brake clean or etc after using a thread chaser (not tap) and use something like Permatex Thread Sealer.
Also, make sure threads in block are clean too.

I thought Gen VI didn't require sealer because the head bolt holes are all blind ended?
Also, ARP includes instructions for using their particular thread lubricant and the corresponding appropriate torque specs.

Thanks
Also need head gasket for .060 over bore

And the bolts go into water jackets

We are using perfect seal on bolts

Maybe that's 454 vs 502. I'm 100% sure my Gen VI 502 head bolts do not go into water passages.

You are probably right but this is a Gev VI 454 with 502 heads

Findings
502 STD bore 4.446
454 bored .060 over 4.310
The first 502 head gasket set picked up was larger then the bore of the 454.

Felpro gasket 1071041 is for a 454 which is bored and has cut outs for intake valves.
Felpro gasket 17048 is for a 502 being a larger bore doesn't need the same cut outs. Will this work?

Can someone verify kit 135-3601 bolt lengths? Made a mistake and bought a set 135-3607 for 454 and was the wrong one. Had 3 different bolt lengths and 8 of them where 5 inches. Picked up 8 additional which came out as 4.25 long which were real close to factory ones at about 4.125 and short were 2.125. Then noticed the 3607 kit bolts were only 4.0 long, so this is where the problem was noticed because they do not extend thru the full thickness of the block.

Standard Merc bolts for motor are 24 each 4.060 and 8 each 2.060
The STD Merc appears to be for the 502 head

502’s are blind. 454’s go into water. Another bonus of 502’s. :thumbs