roller rockers

[dwg86]

It looks like he was using a shaft rocker arm setup. He did use BBC rockers. So maybe the single BBC 1.6 rocker will work? I know they are a lot cheaper than 1.6 AMC rockers. Use a stud with a 3/8 bottom and 7/16 top.

[Alex22]

last week while i was assembling a 4.5 for another member here i had some down time and decided to see what i had that may fit. a 1.7 bbc rocker looked like it should work,7/16 screw in studs,sbc adjustable guid plates. the stud bosses will need to be milled down but i dont see any other reason for it not to work . im gonna find an old head to play with this combo and if i can get a proven setup i will make some kits . i think i can do it for less than $200 with off the shelf parts.

Here's a page where it's been done and he was nice enough to put the machinist drawings out for all to see.

Page 1
http://members.tripod.com/~Mojo_Page/Rokr1.htm

PAge 2 with drawings
http://members.tripod.com/~Mojo_Page/Rokr2.htm

The steel bar that "mojo" made for his AMC head is not nessescary for the 4.0 head since it has individual rocker arm bosses in the head. I was also playing around with this idea for a while but didn't get around to puting the cam and lifters back in to see how far to mill the bosses. There is definatly enough meat there to mill the bosses and drill deeper for a 3/8 rocker stud. I think it was maizie[SP] who used Mopar Magnum rocker arms on his build. 351 cleavland rocker ams look like they will work as well.

[Exos]

I was planning on going with roller rockers, but after reading all this, I'm really unsure. I taught that roller rockers meant more durability, as well as stability?? My plan was to buy these : (S40196A) http://www.harlandsharp.com/amc_jeep_olds.htm

[Plechtan]

Alex22 Wrote:

The steel bar that "mojo" made for his AMC head is not nessescary for the 4.0 head since it has individual rocker arm bosses in the head. I was also playing around with this idea for a while but didn't get around to puting the cam and lifters back in to see how far to mill the bosses. There is definatly enough meat there to mill the bosses and drill deeper for a 3/8 rocker stud. I think it was maizie[SP] who used Mopar Magnum rocker arms on his build. 351 cleavland rocker ams look like they will work as well.

I basically agree with this statement, but if you are not using 1.6 rockers, the pivot point of the rocker should move more towards the pushrod. If the distance from the center of the valve stem to the centerline of the lifter is considered fixed, then as you change ratios, the pivot of the rocker will have to move. Of course you can run the pushrod on a angle, but you will be limited by the clearance on the head. I think you end up with a less than ideal valve train geometry.

It may be easier to move the pivot with a shaft style system. Perhaps a BB Chevy setup could be modified.

[Exos]

So, I'd like some advice on my previous post. Should I go with roller rockers (Harland Sharp adj.), or stick with stamped steel? What are the pluses and minuses of both (besides price, I don't mind paying more if it means durability and performance, if these two words can even be together..) ?

[Exos]

Like I said, I was on the impression that alum. rockers meant more durability, after reading Dino's site, and other posts here. I'd rather have an engine without rocker failure in the 65k range, than have roller rockers giving me 15HP for 65000 miles.

[Alex22]

So, I'd like some advice on my previous post. Should I go with roller rockers (Harland Sharp adj.), or stick with stamped steel? What are the pluses and minuses of both (besides price, I don't mind paying more if it means durability and performance, if these two words can even be together..) ?

basically, whit a good high quality rocker arm the advantage is durability. The stamped steel ones will work as long as you are not trying for very high RPMs or using a strong spring.
At work we use alot of Comp, scorpion and Jessel rocker arms on the stuff we build. But there is a BB Chrysler that we put harland sharp rocker arms on during its last freshen up. I forgot what it was running before but I will find out.

Plechtan, There's no need to be afraid of pushrod clearancing, just grab a die grinder or set it in a Bridgeport iirc, there is alot of room around the stock pushrod. and also, comp hardened pushrods can rub for a long time before it becomes an issue.

[Exos]

Ok.... I would like more input, but, I think I will revert to good quality stamped steel rockers. Looking at my old ones, they look very good, with almost no wear pattern, and they look sturdy. I think I'll buy a set of new ones and go with that, and Mopar perf. springs with a Comp 232-4 and new OEM lifters.

[Alex22]

The BB Chrysler I mentioned before was running the Harland Sharp rocker arms for the last two seasons and the engine got a new set of the same brand because the customer switched to a different style cylinder head. They are a good product, but because they switched to a needle bearing design instead of a bronze bushing a lot of oil will come out of the rocker arms because they are force fed by the pushrods.

There is nothing wrong with using a stock rocker arm if you aren't going crazy with either the cam or the valve spring tension.

[Plechtan]

I sent my Hesco Head off to Harland Sharp last month and they worked up a shaft system for it. I should be receiving the parts this week, and I will post some pictures when i get the system installed. The system will sell for about $1,000.00 which is inline with V8 Shaft systems. The Jesel system is $1,250.00 so the harland sharp is 20% less.

Why do I ( or anybody else ) need this? Well I will be running a Roller cam with a .650 lift at the valve, about 450lbs of spring pressure open. The valves stems are very thin on the Jeep, and you do not want to side load them at all. My valves will be about .300 longer than stock valves. The shaft system is the most stable of all, and the arms are a little stronger because they do not have a slot down the middle.

I will be using a 1.6 ratio, the profiles on a roller all have a great deal of lift, and if i used a 1.7 i would have ended up with over .700 lift. A stock jeep engine has about .450" of lift. The arms will be available with different ratios.

This is probably overkill for a Dual purpose rig or DD, but it would let you have a 1.7 or 1.75 adjustable rocker. The Yella Tera rockers are not adjustable. So you could get a little more lift from your cam, but you would have to be careful on which springs you use. You do not want to bottom them out , and the would have to be strong enough to work with the maximum rpm you are looking for,

[Exos]

excuse my ignorance, but what is the difference between shaft rockers and "pedestal" mount from Harland? Is pedestal mount different from stud mount?

edit: I googled it, found my answers. I still wanna go with adjustable pedestal mount rockers from HS.

[Plechtan]

Good Choice

[Plechtan]

Here are some pictures of the Harland Sharp shaft setup

shaft_rocker_1.gif

Shaft_rocker_2.gif

Shart_rocker_3.gif

[Plechtan]

More pics

shaft_rocker_4.gif

Shaft_Rrocker_5.gif

Shaft_rocker_6.gif

[TurboTom]

Here are some pictures of the Harland Sharp shaft setup

shaft_rocker_1.gif

Shaft_rocker_2.gif

Shart_rocker_3.gif

Pletchtan,
Those stands look awfully tall to get the geometry right. Am I missing something???
By the way are the stands steel or alum.?
Good looking setup though