Roller Rocker on stock head with no machining?

The PIG Smith

I've done some searching and some reading and more corn-fussed than ever. My question: Can a person install a set 1:6 (stock) roller tipped rockers on a stock, post 80's AMC 360 head, without a trip to the machine shop? If so, what vendor/brand/part numbers? I've read where roller tipped 1:6 rocker are provide zero HP gains over the stock OE units. While I may believe this is true, I do feel anything a person can do to increase efficiency is a good thing. My thoughts are, increasing efficiency should let the engine run smoother, easy starts, increase gas mileage, etc...

AMX69PHATTY

Understanding is that Harland Sharp sells full roller rockers, not just roller tipped, that are a direct bolt on for the bridged rocker heads put they can be a little pricey, Part #SH40046A. Someone on the defunct AMCForums was a dealer and gave better pricing. Not aware of roller tipped rockers being available that will replace stock bridged pieces. Maybe some else here knows of some.

They even include a picture of a Hornet on thier new homepage :t:

http://www.harlandsharp.com/

The PIG Smith

AMX69PHATTY wrote
they can be a little pricey

Okay, that's the cold water I needed thrown on me.
I am officially humbled now.

http://store.summitracing.com/partdetail.asp?part=CSP%2DSV4004&autoview=sku
Rocker Arms, Bolt-On Series, Pedestal Mount, Full Roller, Long Slot, Aluminum, Orange Anodized, Kit
$512.95

Summit states this as part number CSP-SV4004.

82Waggy

That's probably not such a bad deal relative to the stud mounted rockers. By the time you machine off the bosses and clearance the head for studs and guideplates and purchase the parts you will have spent about the same if not more than the pedestal mount system costs. I think the Harland Sharp stud mounted rockers are running about $290 a set now. Will cost around 125 for machining, 50 for guideplates, and 50 for ARP studs = 515 to get er done this way. Some have the early heads with slotted pushrod penetrations and therefore elect to forego the guideplates, but that limits pushrod alignment and diameter options. Either way, it is not a cheap upgrade. As an aside, I now have more $ in my 090 castings than a set of new Edelbrocks costs, and I've slept in a Holiday Inn Express before ! 111!!!

401 Pacer

While it's debatable if roller rockers will give your more power or at least less parasitic drag, what they WILL do is prolong valve guide life as they reduce the side loading of the valve stems against the guides. Regardless of what some rocker makers might say, you do NOT want ones with bearings, bushings are better in this instance because the rocker doesn't rotate 360 degrees. No need to trust me on this one, do some research and I think you'll find what I say is true.

milnersXcoupe

What manufacturer for bushed AMC rocker arms do you know of - recommend ? :idea:

jeepsr4ever

The problem is the 5/16" stock bolt for the bridged rocker heads.

jeep_man_401

While it's debatable if roller rockers will give your more power or at least less parasitic drag, what they WILL do is prolong valve guide life as they reduce the side loading of the valve stems against the guides.

I have always heard that the power gain is from less flex of the rocker itself, resulting in extra lift of the valve=more power of course.

The problem is the 5/16" stock bolt for the bridged rocker heads.

Isn't this why they came up with rocker stud girdles for Chevys? less flex of the drive train. PAW carries them for AMC's if I remember right.

Comp. Cams carries a few differnert styles of rockers, one is a stainless set for $407...http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=1132-16&Category_Code=

Now this is assuming you have a big cam with heavy spring pressures.
I have stock rockers on my 360 that I ran years ago and turned 6000rpm all the time with pretty hefty springs and cam. So stock can be done...depends on want you are doing.

Goose

well in addition to the small block Chevy stud girdles minimzing flex.. the Studs on a SBC are pressed into the head and a stud girdle will keep them in the head.. (yes i know they have been tapping them and screwing them in for years..not my point.) Many years ago a young kid brought this small block powered sand rail to me and said, the cam was wearing the lobes off?? when I asked what he meant and if there were metal shavings etc.. he said no... Pulled it down and sure enough the big ol' valve springs and binding rockers had pushed the studs up about a 1/4 " thus the "flat cam and clattering rockers" even though he adjusted them and they were fine for a week..

jeep_man_401

Thats why I'm not a chevy man...only have messed around with AMC's. :?: But now I find the need to use Chevy drivetrain... :oops:

Goose

Well humble opinion here but f you must use a chevy, (And dont get me wrong I still love a SBC just not as much as my ramblers..) find a 400 small block.. absolutely the best bang for the buck.. and dont let people tell ya they crack if they overheat.. thats a load.. they have steam holes in the head/block and all the "experts" decided they would crack..so after 50 jillion of em and no trouble .. not so much.. But with the 400 when you get the "bigger faster bug" you order the 383 kit from jegs and build a mail order stroker.. (the only real advantage the SBC has over the AMC.. is I can go to almost any swap meet and buy any manifold/crank cam whosits ever created for the dang thing for 25 bucks.. cause there are so many of them.. Sigh..oh w)ell..

amundaza

Scorpion Makes the Pedestal Mount Roller Rockers for AMCs. I bought a set recently from Mountain Peformance Online and returned them because I'm going to run the earlier small chamber heads with stud-mounted roller rockers. You can review the Pedestal Mount Rockers with pics on the IFSJA.org forums at http://www.ifsja.org/forums/vb/showthread.php?t=80888

Sincerely,
GregTaylor
Oxford, MI
1989 Grand Wagoneer : Water/Hydrogen Injection 360-V8. 4.5" lift 31" BFG A/T's. Killer32 front bumper