Roller rockers on a 74 AMC 360?

FullSizeJeeper

I've been researching what I need to do to put roller rockers on my stock 74 heads. Sounds like the stud mounts on the heads need to be milled down and the tapped out to match a conversion kit. The pushrod holes are round, thus I need guideplates and hardened pushrods. The pushrods are easy, several companies make them and don't seem to be much difference. (I think the chevy 350 pushrods are the same size as the AMC, 7.8" long and 5/16" dia?) As to the guideplates and studs, any ideas where to find them? I see conversion kits for Ford and Dodge, but not for AMC, will one of these work? The stud holes are 5/16 currently. If I retapped them to 7/16 and used the ford 7/16 conversion kit by crane cams 52655-16 (availabe at summit) would this work? If not any other pruduct suggestions for Guideplates and studs. I was going to use the Crane aluminum roller rockers. Seems like the AMC 1.6:1 are a good product for price, any other suggetions? I guess the final question is how much to mill the stud mounts, but hat will probably depend on the guideplates, any advice there? Tring to get the most out of my built 360, it currently is bored .030 over, summit 214/224 cam and lifters, Edlebrock preformer intake and 600cfm carb, roller timing chain, K&N air filter, headman headers, and some bling. This goes in my FSJ daily driver/trail rig so I'm looking for mostly low to mid range no high RPMs

tufcj

I used ARP studs for a SBC with girdles. 7/16" where they thread into the head, and 3/8" on top. I used Crane Gold rockers, and had to use a +.100" pushrod to get the geometry right on a 69 390 block with 70 heads.

Most heads need to be milled around .250" + the thickness of the guide plate.

For guide plates look here:

http://www.amcforums.com/cgi-bin/yabb2/YaBB.pl?num=1115854071

Bob
tufcj

FullSizeJeeper

Thanks for the quick reply, I'll contact roguesc1 about the guideplates. The ARP 134-7104s are what you used for studs? Are there any major difference in the crane golds vs. the crane energizers other than the gold coating and a $120 price jump? Do you think the 74 head will need to go to the +.100 pushrods? The difference in price is significant. Should I machine it, instal the rockers and test the length, before getting the longer pushrods? What should I look for to determine if I need the +.100 rods? I've got plenty of time, probably a year before I drop the built engine back in ( :(: emmissions regs up here, no mods allowed to pass test, even if the rig runs cleaner with the mods 111!!!)

tufcj

I used the crane gold rockers because I got a screaming deal (brand new w/cool nuts for $175 off ebay). A lot of people will tell you that rollers aren't needed below 5000 RPM, but the lower friction with the tip of the valve will increase the life of the valve guides, and they say they're good for about 10-15 HP. That's the exact ARP # that I used for mine. The energizers are cast, the golds are extruded, which makes the golds stronger. Probably won't make a bit of difference on a street motor. You have to assemble the engine to check geometry. You want the tip of the rocker centered on the head of the valve, and you want it to stay centered as the valve opens. Remember that the pushrods are the same length as a SBC, so sometimes asking for the GM part will save you money, even though they're identical. Bob tufcj

FullSizeJeeper

Do you know the stock boss height on pre 74 AMC heads? David said his guideplates on pre 74 heads simply need the bosses milled the thickness of the GPs. However, on the 74 and later, he recommended milling the bosses to match the pre 74 height then removing the the thickness of the GP.