• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Roller rockers time?

Mark1972

Well-Known Member
Local time
8:18 AM
Joined
Jun 26, 2018
Messages
358
Reaction score
285
Location
Winnipeg
Punched another pushrod through a stamped steel rocker last Sunday. That's two in two years. Was looking at these:

https://www.hughesengines.com/Index...a2VyIEFybXMgJiBBY2Nlc3Nvcmllcw==&partid=26774

440
Edelbrock E-Street 75cc heads
Been using stock stamped steel rockers
CompCams XE268H 224/230 477/480

It's a cruiser, not a race car, but one of these days I'm worried I'm going to do more damage than just ruining a rocker and pushrod. Any thoughts appreciated. Also looked at Harland Sharp, but am waiting for an email back from them to see if they can fit these heads. Hughes advertises they will. Also, I assume no reason to go 1.6 from stock 1.5 for my purposes. As always guys, thanks.
 
There was some for sale here
 
Personally I'd be looking for ductile iron rockers... Isky/OE/Crane/Erson... Last word in reliable long term service..
 
I remain an Isky ductile fan. They served me very well over the years. Crane, not so much. The Hughes rockers I have are excellent.
 
I would go with the Ductile Iron Rockers for you application.
You should be able to find a nice complete set with everything
for $350.00 I trust them much more on a street car.
 
I've reached out to Isky and Erson. Waiting for a response. Crane rockers show up on Summit as singles, not sets. I'm having a tough time even finding Crane online. This morning I'll reach out to Edelbrock and talk to them as well. I don't think they make adjustable rockers, but they may have some input on what they recommend for the Edelbrock E-Street heads.
 
Punched another pushrod through a stamped steel rocker last Sunday. That's two in two years. Was looking at these:

https://www.hughesengines.com/Index...a2VyIEFybXMgJiBBY2Nlc3Nvcmllcw==&partid=26774

440
Edelbrock E-Street 75cc heads
Been using stock stamped steel rockers
CompCams XE268H 224/230 477/480

It's a cruiser, not a race car, but one of these days I'm worried I'm going to do more damage than just ruining a rocker and pushrod. Any thoughts appreciated. Also looked at Harland Sharp, but am waiting for an email back from them to see if they can fit these heads. Hughes advertises they will. Also, I assume no reason to go 1.6 from stock 1.5 for my purposes. As always guys, thanks.
Geez what kind of seat pressure are you running because your cam lift isn't that crazy? Was it the same one that went south?
 
2 years ago, it was #4 cylinder exhaust valve. Last week it was #7 cylinder intake valve. Waiting for the engine builder to call me back now that I've discovered the problem.

IMG_20220815_074238.jpg
 
The Isky ductiles will you a long reliable service, even under extreme use.
 
Since they don't make any ductile rockers currently if you go that way you'll be searching for a used set.... They pretty much stopped making them twenty plus years ago since everyone buys roller rocker cause they are bling... Ductile are boring.. But they are as reliable as a stone..

Whereas roller rockers do all kinds of interesting stuff & yes there is even a picture of a failed Harland Sharp in thee...

Screen Shot 2022-08-15 at 8.02.06 AM.png
Screen Shot 2022-08-15 at 8.01.21 AM.png
Screen Shot 2022-08-15 at 8.00.18 AM.png
Screen Shot 2022-08-15 at 8.00.02 AM.png
 
Get the Hughes set. I have them and they are fantastic. Originally I had a set of Crane ductile iron I bought new and the tips were soft and wore down within a year. Used , old ones might be better made but why buy used, old technology?
 
Since they don't make any ductile rockers currently if you go that way you'll be searching for a used set.... They pretty much stopped making them twenty plus years ago since everyone buys roller rocker cause they are bling... Ductile are boring.. But they are as reliable as a stone..

Whereas roller rockers do all kinds of interesting stuff & yes there is even a picture of a failed Harland Sharp in thee...

View attachment 1328844View attachment 1328845View attachment 1328846View attachment 1328847
I have several sets for big and small block ductiles that have been
sitting 40 years.
 
I agree with @68Moparmaniac asking what your spring pressures are. No doubt the suggestions above can address the issues you have blowing through rockers, but why is that happening in the first place? A decent street engine should have 100# seated and 300# open give or take unless you are going to be revving the heck out the engine. More spring pressure is needed for high revving engines, but why put lots of extra pressure on your rockers, lifters, pushrods and cam if you don't need to (plus parasitic loss on top of that)?

Note: my above comment assumes a general "street" build engine. I don't know the specs of your engine, cam etc. so maybe you need the high spring pressures? But if you don't...
 
Hey guys. So first, I don't know the valve spring pressure. Edelbrock advertised 120lbs, but doesn't give the pressure at .500" lift. I don't have a tool, and none of the loan a tool programs locally have them. Possibly Edelbrock tech support knows, but I waited on hold for 30 minutes and had to get off. I did make a decision, for right or wrong on the rockers. The machine shop has had really good luck with the CompCams 1621-16 units for the Mopar big blocks. Link below. So I went that way. Last night I followed the pushrod measuring process and got those numbers to the shop, so they can order them. Hopefully these units will do the job. I'm hoping the pushrods are here by Friday so I can assemble everything and have the car out this weekend. Time will tell.

COMP Cams 1621-16 COMP Cams Pro Magnum Shaft Mount Roller Rocker Arms | Summit Racing
 
Edelbrock BB Chrysler E-Street Cylinder Heads # 5090 have 130lbs Seat Closed Pressure, and @ 1.400” Open Pressure is 280lbs, and also for Hydraulic Flat Tappet Camshafts Only, All E-Streets and All, Engine Families….

This was the response from Edelbrock tech support by email asking about the spring pressure.
 
Edelbrock BB Chrysler E-Street Cylinder Heads # 5090 have 130lbs Seat Closed Pressure, and @ 1.400” Open Pressure is 280lbs, and also for Hydraulic Flat Tappet Camshafts Only, All E-Streets and All, Engine Families….

This was the response from Edelbrock tech support by email asking about the spring pressure.
OK, I'd call that "normal" for a street engine. No way that should be enough pressure to be blowing through rockers.

Were the rockers in good shape? Note that on stock rockers the metal surface where the rocker touches the pushrod is hardened, but the rocker is not hardened all the way through. Even a little bit of wear here means that the rocker will wear quickly and cause you grief. Could that have been an issue?

It's spilled milk now since you have ordered a new set of rockers. But it might be good to check your old ones carefully.
 
The Comp pro magnum are prone to gulling. Photo in article below look about the same as my friends set:
https://www.hughesengines.com/TechArticles/6stainlesssteelironrockerarmsthiscanbeagauldingexp.php

Changing rockers, the pushrods are likely going to be different length and tip configuration too.

I would just get the Harlan Sharpe Rockers (they come with spacers and hold downs too):
DODGE Harland Sharp S70015K Harland Sharp Heavy-Duty Roller Rockers | Summit Racing

I don't know the exact difference between the S70015K and the S70015KE?, but the KE is way more expensive. I know the "KE" version is what Trick Flow recommends.
I have run the S70015K on the RPM Heads with no problems? I also have the 1.6:1 ratio HS rockers on the 505" stroker with the Stealth heads.
 
Would like to know what aftermarket Rocker Arms you went with back in 2020

I posted in your other thread about my observation with Elgin brand stamped steel rockers

I run the E Street Heads 5090 on my 383/432 Stroker
Comp Cams XE275 HL

Comp Cams magnum chromoly push rods

Sealed Power Stamped Steel Rockers and Shafts
No longer made

Going on six summers now with this set up on the street
 
Auto Transport Service
Back
Top