454 ARP and exhaust manifolds
 

So I'm into the final assy of the rebuilt 454 I'm putting in place of the original 350 in my '69. I used a nice set of ARP head bolts. Going to put the exhaust manifolds on first so I don't have to fight them over the fenders and glad I did. Turns out the manifolds hit the top of the ARPs, thus not letting them fit flat on the cylinder heads. The manifolds are new Dormans so I'm not too fond of grinding on a brand new manifold. As it is now I am sanding (with my air sander and 36 grit) the top and one edge of the bolt head... Yikes. Still plenty of meat on the bolt itself, but.... Anyone else run into this or is it headers for everybody. Not a header fan myself on a daily hauler

Re: 454 ARP and exhaust manifolds
 

:wop:

Re: 454 ARP and exhaust manifolds
 

Yes we had the issue on our 468 build, and my dads neighbor had issues with his big block.

both of us using headers but different applications. I don't know what brand he used. our were hooker for a 79 c30

it would probably take you a long time to sand down ARP bolts, as they are pretty hard steel.

we ended up just putting stock head bolts back in the bottom row. my dads neighbot ended up having his ARP bolts machined down to fit.

Re: 454 ARP and exhaust manifolds
 

They actually sanded down pretty quick with 36 grit and my air sander. Couple of pics for ya

Re: 454 ARP and exhaust manifolds
 

Do you absolutely need the washers? might give you a little room and not have to shave so much of the bolt. just a thought...

Re: 454 ARP and exhaust manifolds
 

Yeah I thought about just that, but I didn't want to disturb the torque settings. What you see is completed, everything is clearanced and torqued down.

Re: 454 ARP and exhaust manifolds
 

What are the silver bolt heads? Are those plugs for an air injection? I like the shields and with all that cast iron mass they're going to be necessary. It looks good and as long as everything is clearanced you should be good to go. Personally, I wouldn't have touched them bolts before giving them manifolds the once over with one of these but thats just me... ;) http://appliedmaintenance.com/images...ROTO_FILES.jpg

Re: 454 ARP and exhaust manifolds
 

The Dorman manifolds are already pretty thin without grinding on them, that's why I went the other way. And yes the plugs are the air injection holes. All the replacement manifolds are universal, even down to the O2 sensor hole.

Re: 454 ARP and exhaust manifolds
 

Fascinating. I did a quick google with "454 gm arp head bolt clearance with stock manifolds" in the search term box and saw that a few others had the same issue -- even with headers. Those guys were either grinding the header flange or searching out stock bolt sets without the fat washer.

Good to know if I ever get tired of my small block.

Re: 454 ARP and exhaust manifolds
 

You may have had clearance issues anyways with the Dorman imported cast manifolds...., but WHY did you use the washers?? Just because they were in the kit?
Washers are necessary to keep the hard steel bolt from gauling ALUMINUM heads and influencing torque value. . You don't need the washers with iron heads (which these appear to be with that casting texture and casting flash,,, but they 'may be' painted aluminum heads???) Regardless iron and steel will not gaul so just the ARP moly torque lube and no washer would have been perfectly fine here.

Grinding on the bolt before, removing the washers is definitely not the prefered way to get clearance here. Hopefully it doesn't jump up and bite you on disassembly.Be sue and use a 6point socket on those that you reduced the hex flats of.