FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: ChiefDanGeorge on February 16, 2016, 04:50:23 PM
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In the process of ordering various hardware and thought I'd see what the preferences were for attaching heads. I see ARP has both studs and bolts.
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Are you using stock heads? If so the ARP will work but buy 12pt nuts for aftermarket heads. If using T&D or other rockers some require special Allen bolts. I ended up with studs outside and Allen bolts inside to work with my T&D race rockers with 12pt nuts to clear the exhaust ports. I also had to smooth the ares around the port a little to clear the socket.
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Using Edlebrock heads and Harland Sharp rockers.
Are you using stock heads? If so the ARP will work but buy 12pt nuts for aftermarket heads. If using T&D or other rockers some require special Allen bolts. I ended up with studs outside and Allen bolts inside to work with my T&D race rockers with 12pt nuts to clear the exhaust ports. I also had to smooth the ares around the port a little to clear the socket.
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If a torque plate was used to hone the block, use whatever fastener was used to do that.
Otherwise, in all but the most severe applications, bolts work just fine.
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If a torque plate was used to hone the block, use whatever fastener was used to do that.
Otherwise, in all but the most severe applications, bolts work just fine.
Even stock bolts are fine for most street performance builds. I have yet to have a stock head bolt fail in any of my long-term engines. If it were mine, I'd start considering replacing them if I didn't have a good set, or if I were starting to push the horsepower up considerably over stock.
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I bought a 427 CO block this year with the knowledge that there is a small crack between two head bolts and the water jacket. One on each bank.
Seller, a long time acquaintance, also provided a stud set for the heads. The builder I'm using (local to me) said all should be fine with sealant in the holes for the studs.
Just my knowledge. This my first 427 block.
Richard
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For the heads you can use either the ARP bolts or studs.
On the Edelbrock head you "should" drill the bolt hole on each head where
the oil supply hole is. Drill it to 9/16" which is the stock factory size.
You may have oil supply issues if you don't.
While you're drilling holes in your heads.
Drill out the return holes also, the return holes are only .437" on the Ed's and
on stock they are .610".
Now will be a good time to start making up the oil restrictors for the heads.
You need a 3/16" rod and drill a hole .070" in it. That will fit in the oil supply hole on
the Ed heads.
Use the studs for the rocker stands.
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I did open up the oil feed to 9/16" on both heads(I read and re-read your modification thread). For the oil return, I was going to have them opened up as well, but I am questioning if that is really needed. Is the oil drainback an issue with a normal volume pump or an HV pump?
For the heads you can use either the ARP bolts or studs.
On the Edelbrock head you "should" drill the bolt hole on each head where
the oil supply hole is. Drill it to 9/16" which is the stock factory size.
You may have oil supply issues if you don't.
While you're drilling holes in your heads.
Drill out the return holes also, the return holes are only .437" on the Ed's and
on stock they are .610".
Now will be a good time to start making up the oil restrictors for the heads.
You need a 3/16" rod and drill a hole .070" in it. That will fit in the oil supply hole on
the Ed heads.
Use the studs for the rocker stands.
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I think it is.
If you put a head bolt in the hole and look at the area around the
hole that is on the intake face you can see how little area there is for oil drain.
If you open the drain hole that small area gets bigger.
Also blending the valley in the upper drain area will help a lot.
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Chief,
If ya need a set of stock headbolts, let me know. I've got a few sets of them in good condition. For the junk I'm building now, I'm erring on the side of overkill.
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I use studs everywhere I can on my engines. Heads, mains, oil pan, make my own for oil pumps, intake if possible, etc.
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Chief,
If ya need a set of stock headbolts, let me know. I've got a few sets of them in good condition. For the junk I'm building now, I'm erring on the side of overkill.
Actually stock head bolts don't fit that good on Ed heads.
You have to machine some of the bosses so you can get the socket on them.
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I would first base it on how the block was prepped.
Second to that would be how much hp/compression you're working with. However, I just built a 777 hp Clevor with 13.5:1 that worked just fine with bolts.
A distant third would be looking at how much clearance you have to get the heads off and how often you'll be having to pull them. Studs make it a little more time consuming to get the heads off in the event of a tear-down or inspection if you can't slide the heads up over the studs. Of course, aluminum blocks get studs as a default.
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If you're putting the engine in a shock tower car, and think you might ever want to remove a head while the engine is in the car, you might want to use bolts instead of studs.
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2X on bolts for a shock tower body style, studs or bolts for say a wide-bay Galaxie.
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It's a Colony Park wagon.
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Could you explain the first one, how does that have an affect on the fasteners?
I would first base it on how the block was prepped.
Second to that would be how much hp/compression you're working with. However, I just built a 777 hp Clevor with 13.5:1 that worked just fine with bolts.
A distant third would be looking at how much clearance you have to get the heads off and how often you'll be having to pull them. Studs make it a little more time consuming to get the heads off in the event of a tear-down or inspection if you can't slide the heads up over the studs. Of course, aluminum blocks get studs as a default.
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Doesn't affect the fasteners, but affects the block. Bolts will stress/distort the block differently than studs, so if your machinist used bolts on the torque plate and you put head studs in, you could potentially see a difference in cylinder shape. Same with the mains....mains will distort so you always have the mains honed with the fasteners you're going to use.
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Ah, ok I understand. Thanks for the explanation.
Doesn't affect the fasteners, but affects the block. Bolts will stress/distort the block differently than studs, so if your machinist used bolts on the torque plate and you put head studs in, you could potentially see a difference in cylinder shape. Same with the mains....mains will distort so you always have the mains honed with the fasteners you're going to use.
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Not sure i'm following the logic of drilling the head bolt hole larger so it doesn't restrict the oil and then plugging the passage above it to restrict oil. :-*
If it blocks it off completely just file a slot from the deck up to where it intersects that passage.
Make sure the drains have room around the bolt or stud, not just the diameter of the hole, it flares around the bolt too.
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If it blocks it off completely just file a slot from the deck up to where it intersects that passage.
I guess I could go to the file drawer and get a file, but I hate filing.
In the olden days one of the machinist apprenticeship projects was to make a file.
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N/m
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If you're putting the engine in a shock tower car, and think you might ever want to remove a head while the engine is in the car, you might want to use bolts instead of studs.
Not here. I'm of the opinion that if a head needs to be pulled, it's all coming out and going on a stand. I ain't lifting 50 lb heads over a fender anymore, screw that :)