Bolts for Eddie heads?

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doogievlg

doogievlg

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I was looking at my old stock head bolts and was curious if they will work with my Eddie rpm heads. If not then what kit is best to buy?
 
Put the bolts into the heads with out them installed on the engine. See how much of the bolts/threads stick out the bottom. There should be at least 3/4 inch of threads sticking out.

Minimum thread engagement is 1 1/2 times the diameter of the bolt. Ie. a 1/2" diameter bolt times 1 1/2 equals 3/4", so you would want a minimum of 3/4" threads. (1" would be excellent if you have enough threads in your block)

I would then screw one into the engine and see how deep the threads in the block go. Then make sure that the bolts will not bottom out. Make sure that there are more threads in the block than you have sticking out of the bottom of the head when you "test fit" the bolts for length. But you must have a minimum of 3/4" to hold the torque required for a head. One inch would be great if your holes in the block are threaded deep enough. (Caution - check the thread depth with another bolt, not a wire. They always drill the hole deeper than it is threaded for "chip allowance". Chip allowance is to allow some chips to fall into the hole while tapping out the hole, so the chips won't fill the hole and the tap "bottom out" before the tap is finished threading the hole when they machine the part.)
 
doogievlg said:
If not then what kit is best to buy?
Click to expand...

You would definitely want to get a good grade 8 head bolt. I would try Mancini racing, summit, or any of the fastener suppliers here that make reproduction bolts, ARP, SPS etc. The head bolts are 1/2" coarse thread. I believe 1/2" x 13 threads per inch.

Figure out what length you need as I described in my other post above and then look for those lengths. Remember one of the "long" head bolts is longer than the rest as it has a higher "boss" in the head. Make sure that you check each hole in your head (pun intended) to make sure that you have the proper length. Maybe draw a "map" of the bolt pattern for your head on a sheet of paper and number them. Then under the diagram list 1-10 and then use each line to record what length/depth bolts you will need.
 
With aluminum you want a flat ground washer under the head bolt or it will gall the head and potentially loose clanmping load over time. The ARPs are not really expensive - just buy them.
 
ARP makes a bolt set specifically for the RPM heads. I have them on my 360. I would not reuse the stock bolts. Something in the dark recesses of my memory is prompting me that there is an issue with them in this application.
 
rapom65 said:
ARP makes a bolt set specifically for the RPM heads. I have them on my 360. I would not reuse the stock bolts. Something in the dark recesses of my memory is prompting me that there is an issue with them in this application.
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I don't recommend re-using stock bolts also unless you know how many times that they've been torqued. If they have been torqued too many times, they can stretch and that can lead to premature failure...


Nobody likes "premature failure"...
 
here's the general instruction sheet for the heads

[ame]http://static.summitracing.com/global/images/instructions/edl-6077_inst.pdf[/ame]
 
Thanks. Hopefully I'll run up to jegs before the weekend and get everything. I'll post pictures!
 
With Edelbrock heads, there are two of the longer bolts per head and the ARP kits only come with 1 per head for normal LA castings. If you're buying Edelbrock heads new, they will issue with the spare bolt. If not, just call ARP and tell them your plight and they'll probably just send you 2 more bolts as necessary...just ran into this a few weeks ago with a new 340 build.
 
Normally I would say go for the studs, but I will be using bolts otherwise to remove the drivers side head you will have to remove the booster and or master cylinder, or if your real froggy take the engine out lol
 
cumminsperformanceparts.com 144-3603 part number $61.75 shipped for arp bolts
 
jrwood said:
Normally I would say go for the studs, but I will be using bolts otherwise to remove the drivers side head you will have to remove the booster and or master cylinder, or if your real froggy take the engine out lol
Click to expand...
Unbolt booster and slide it out of the way. No need to disconnect master cylinder either from booster or hyd lines.
Totally worth it to use Studs.
 
moper said:
With aluminum you want a flat ground washer under the head bolt or it will gall the head and potentially loose clanmping load over time. The ARPs are not really expensive - just buy them.
Click to expand...


The washers need to be hardened too
 
txstang84 is right. The eddy heads have 2 long instead of 1. I had a set or arp head bolts for standard heads and had to order the ones for the eddy's. The bolts otherwise are the same. Hardened washers come with the bolts and are a must.
 
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