Harland sharp roller rockers on 304

hound51

i'm trying to find information on which ARP studs i need to get to make bolt in with out haveing to do any machineing work on my factory heads. can anyone help?? 1976 cj-5, 304

tufcj

If you're trying to use a Chevy style rocker, you have to machine the pedestal and install guide plates on 74 and newer heads, there's no way around it.

If you're using the Harland Sharp SV4004 rockers (bridged together), they include the stud kit if you buy them new. I don't know if ARP makes one that will retrofit. The catalog lists it as a .650" long pedestal 1.750" bolt. You might contact them to see if you can buy the studs separately.

http://www.harlandsharp.com/bolton3.htm

Bob
tufcj

Mudrat

tufcj wrote
If you're trying to use a Chevy style rocker, you have to machine the pedestal and install guide plates on 74 and newer heads, there's no way around it.

If you're using the Harland Sharp SV4004 rockers (bridged together), they include the stud kit if you buy them new. I don't know if ARP makes one that will retrofit. The catalog lists it as a .650" long pedestal 1.750" bolt. You might contact them to see if you can buy the studs separately.

http://www.harlandsharp.com/bolton3.htm

Bob
tufcj

Bob,
I've been looking at those (the SV4004) for the360. I had a guy tell me today that he's seen some of the HS's grenade inside a Chebby engine :shock: When the rocker cover was pulled off there were needle bearings all over???

Have you heard anything like that?

Pat

hound51

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=4026&prmenbr=361

These are the roller rockers that i have and i hear something about a regular 3/8 stud will work but just would like to make sure before going the wrong way on a spending spree

Mudrat

Hound,
That's what HS recommends on their page for a 3/8 stud (about halfway down).
Note what they also add ...
"1974 and newer heads require studs and pushrod guide plates
Extra relief cut for stud clearance"

bricklin

I had a guy tell me today that he's seen some of the HS's grenade inside a Chebby engine :shock: ....Pat

Averybody has a failure once in a while. I'm sure the failure rate for made in USA harland sharpe rollers are much lower than the cheep chinese stuff you find all over ebay. I have used HS rokers for years on fords and never had a rocker related problem.

Mudrat

bricklin wrote
Averybody has a failure once in a while. I'm sure the failure rate for made in USA harland sharpe rollers are much lower than the cheep chinese stuff you find all over ebay. I have used HS rokers for years on fords and never had a rocker related problem.

Allllrighty then :mrgreen: Thanks bro...- shopping for the best price on a set of HS 4004 rollers!!
Jegs was 215, Summit was 205 ... anybody have an "in" with HS somewhere???

Pat

bricklin

while talking to "one of the family" at HS , they told me that jegs and summit are by far their 2 biggest customers and they demand special pricing. I doubt if you could find better pricing even if your "local guy" gave them to you at cost. That price is pretty good for USA made product, almost the same as the ones made in china where the workers are paid with a bowl of rice.

tufcj

:smile: I think bare minimum what you'll run into on a stock 74-up bridged rocker head is that the stud hole in the head is 5/16". ALL screw in studs that I've seen are minimum 3/8", a lot are 7/16", so the holes need to be drilled and tapped. The later heads also have round pushrod holes, they relied on the rocker bridges to hold the arms straight. Without the bridges, you need a guidplate to hold the pushrods/arms straight. Now you need somewhere to bolt the guideplates down (approx 1/8" thick). That's under the rocker studs, which makes them too high to adjust the rockers down without running out of threads or hitting the stud base, even with an extra relief. Most 74-up heads take about .250" machined off the rocker pedestal to work with standard roller rockers. Some take even more if the guide plates are thicker. On my 390, I also had to use .100" longer pushrods to get the geometry right on the rockers (Crane Gold). Don't forget that you need hardened pushrods with guide plates or pre-74 heads. Standard pushrods will wear quickly and severely, and the metal frags will ruin your oil pump and bearings. Bob tufcj

Mudrat

tufcj wrote
:smile: I think bare minimum what you'll run into on a stock 74-up bridged rocker head is that the stud hole in the head is 5/16". ALL screw in studs that I've seen are minimum 3/8", a lot are 7/16", so the holes need to be drilled and tapped.

The later heads also have round pushrod holes, they relied on the rocker bridges to hold the arms straight. Without the bridges, you need a guidplate to hold the pushrods/arms straight.

Now you need somewhere to bolt the guideplates down (approx 1/8" thick). That's under the rocker studs, which makes them too high to adjust the rockers down without running out of threads or hitting the stud base, even with an extra relief.

Most 74-up heads take about .250" machined off the rocker pedestal to work with standard roller rockers. Some take even more if the guide plates are thicker. On my 390, I also had to use .100" longer pushrods to get the geometry right on the rockers (Crane Gold). Don't forget that you need hardened pushrods with guide plates or pre-74 heads. Standard pushrods will wear quickly and severely, and the metal frags will ruin your oil pump and bearings.

Bob
tufcj

OUCH!! And this after $250 in machine work and 3* valve job - may have to stick with stnadard rockers for a while ...

Pat

hound51

with all this great info...looking around is there any certain guide plates that should be used? i've seen everything from edlebrock to cran cams to summit brand guide plates and haven't seen any that are speccified for the AMC 304 engine. any ideas?

73hornut

Can someone use 3/8 chromolly pushrods on the 74 and later heads, and get away without using guide plates?

ol' school power

bricklin wrote

I had a guy tell me today that he's seen some of the HS's grenade inside a Chebby engine :shock: ....Pat

Averybody has a failure once in a while. I'm sure the failure rate for made in USA harland sharpe rollers are much lower than the cheep chinese stuff you find all over ebay. I have used HS rokers for years on fords and never had a rocker related problem.

Many people beat Harlands to death including myself.
Bunch of the Mopar folk use the paired sets on the Magnum motors in both 1.6 and 1.7 ratios without failure.
There's always 2 sides to a story and not knowing what the Chubby guy did still leaves one end open.

Mudrat

ol' school power wrote
Many people beat Harlands to death including myself.
Bunch of the Mopar folk use the paired sets on the Magnum motors in both 1.6 and 1.7 ratios without failure.
There's always 2 sides to a story and not knowing what the Chubby guy did still leaves one end open.

Well I have quite a few open ended wrenches too :shock:
but understand the different sides to a story, that's why I asked. Now to muster up the extra bucks for the machine work ... and with the SV4004's that are bridged, would I still need the guide plates?

Pat

ol' school power

Mudrat wrote
ol' school power wrote
Many people beat Harlands to death including myself.
Bunch of the Mopar folk use the paired sets on the Magnum motors in both 1.6 and 1.7 ratios without failure.
There's always 2 sides to a story and not knowing what the Chubby guy did still leaves one end open.

Well I have quite a few open ended wrenches too :shock:
but understand the different sides to a story, that's why I asked. Now to muster up the extra bucks for the machine work ... and with the SV4004's that are bridged, would I still need the guide plates?

Pat

No plates or mods required. They're connected pairs so they stay aligned with each other.

Mudrat

Mudrat wrote
ol' school power wrote
Many people beat Harlands to death including myself.
Bunch of the Mopar folk use the paired sets on the Magnum motors in both 1.6 and 1.7 ratios without failure.
There's always 2 sides to a story and not knowing what the Chubby guy did still leaves one end open.

Well I have quite a few open ended wrenches too :shock:
but understand the different sides to a story, that's why I asked. Now to muster up the extra bucks for the machine work ... and with the SV4004's that are bridged, would I still need the guide plates?

Pat

Well Harland was the inventor and still tops according to thier history page and other writes ups I've read fom around the world. Your experiance and saying guides are not required are good enough for me.

Now the question, 3/8 or machine work for the 7/16 studs?

Pat

ol' school power

KI say neither. I believe if you check with them ( Harland) those are bolt on series using stock size bolts.

hound51

the SV4004 rockers have a bridge on them but the S4004 roller rockers are seperate peices, so i'm guessing i need guide plates...any idea what ones i need on a 304?

ol' school power

Which rockers were on there originally? If they were bridged, then you need to have the boss's milled down and all the holes redrilled and tapped with 7/16 threads.

hound51

the factory original were on before...i have a machinist already drilling them for 7/16 and told him i am going to need them milled down for guide plates but need to find the right guide plates so he can get it right. any idea on a which one is right? Dave