Edelbrock Rpm heads on 360

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Danny denial

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I have a sweet wee 360 with 30thou hyperutechnic pistons, balanced and running 4 speed 833 O/D with dodge 8 1/4 3.9 LSD. Its in a rough old 1971 Valiant ute.
Have done about 1000miles in it and it went well with steel J heads 1.9intakes,
Have just purchased some edelbrock RPM heads to go on it.
Heads have been checked over and reassembled and the springs to suit cam installed.
Planning on using factory rocker gear off the J heads.
My question is will my rockers and pushrods fit the new heads?
Have a head stud kit and felpro gaskets but looks like I need some 1008s.
Anything else I should be aware of before I install them?

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Nope. All will work just fine as long as the cam is mild. And you dont get carried away
I did this exact same thing. Took a bone stock 70’ 340 with 2.02 J heads and just some bolt ons i had added( headers, holley 700, aluminum dual plane intake) and swapped on stock eddie heads and added a hughes hydralic cam.... if i remember it was 230-238...... reused the pushrods and factory rocker gear.
Drove it that way for awhile before i started worrying about pushing holes in the factory rockers and replaced them with Cranes.
 
Nope. All will work just fine as long as the cam is mild. And you dont get carried away
I did this exact same thing. Took a bone stock 70’ 340 with 2.02 J heads and just some bolt ons i had added( headers, holley 700, aluminum dual plane intake) and swapped on stock eddie heads and added a hughes hydralic cam.... if i remember it was 230-238...... reused the pushrods and factory rocker gear.
Drove it that way for awhile before i started worrying about pushing holes in the factory rockers and replaced them with Cranes.
Cool thats good news then, Thanks
 
Edelbrock recommends 1008's for a reason...as for the heads nice upgrade running a set on my current "stock stroke" 360 best so far 11.78..have another set that have been cnc'd by Hughes along with upgrading the intake valves to 2.08's and much better springs and locks(installed by my builder)..trying to decide what to put them on.as for your rocker arms don't know if I'd trust factory ones especially if you've got some good lift in that cam..
 
Compression, You are going from a open chamber head to a closed chamber. You will want to measure compression ratio. How far are the pistons in the hole, flat tops? Also what do you have for exhaust manifolds. An A body stock 340 exhaust manifold style can hit the eddy head on the drivers side. Not sure what your ute has. Also alternator can hit the head. Not insurmoutable issues just things to keep in mind. Also they take a different head bolt/stud kit.
 
What furry said
which hyper piston
what's your compression height and deck clearance
if 0.0 deck with a FT use the .040 fel pro
if down the hole .010 use the .028 gasket
if down more than .010 you got work to do
stock rockers should be fine- if you go roller tips you have to shim/ relocate the shafts PITA but necessary (a hidden cost to roller rockers)
did you say what cam?
if you do not have it apart yet do a compression check first and report
 
only problem you might encounter is the spring pressure will push the pushrod thru the rocker arm seat....
 
magnum lifters and oil through the pushrods helps on the pushrod through the rocker problem
use them on iron rockers and roller rockers too adjuster balls smoke too
 
I have the same combo with the Hughes 230/237/110 cam, A833/3.09low, but with 3.55s. At 10.9Scr it is a screamer, and even 325/50-15 BFG-DRs cannot tame it.
Get some big brakes,big front tires, big suspension, and extra insurance, and go have some big fun..

I run the Hughes 1110 springs and roller-tipped-only adjustable aluminum rocker arms.I highly recommend adjustable valve gear and minimum lifter preload; with a manual trans, missed-shifts are a common thing and the minimum preload can save your engine.

If you run factory rockers, IIRC the 340 ones are a little meatier in the critical areas and are factory modded for spring/retainer clearance. But if she punches an arm, bends a pushrod, and catapults a lifter,at 7500, that can be a catastrophic oil pressure loss, with near instant rod-bearing failures following.
 
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magnum lifters and oil through the pushrods helps on the pushrod through the rocker problem
use them on iron rockers and roller rockers too adjuster balls smoke too

with stock oem rockers it is not an issue with oiling....it is the spring pressure that punctures the rocker...
 
I used the stock eddie springs( which arent very stout) and didnt have any issues
The HE3038AL peaks around 5400 with my Eddies, in a 367. With an auto that calls for a shift rpm up to 1000 rpm higher. I didn't try to take the stock Eddie springs that high; I have 1.6 arms, which,with that cam's advertised lifts is .549/.571. The Hughes 1110s go 7200 all-day long.
That cam is a real good ripper @10.9Scr........I have a manual trans.
 
only problem you might encounter is the spring pressure will push the pushrod thru the rocker arm seat....

If that's the case..Maybe he can get away with a pop up retainer or .050 pop up locks, that is if they still have enough to control the valves aka fall within the psi range recommended.
 
the extra oil really helps on the push through problem
most are blue from heat where pushed through
 
I just installed a set of 60779's on my 360 and tried using stamped steel rockers.They hit the valve spring retainers.Luckily I had a set of 273 rockers lying around.
 
how much lift? should not hit retainers - stock size springs? good fix but check the stripe on a valve stem top with some dykem and check- it should be NARROW
 
I have added an image of my Lunati cam specs and a picture of how far the pistons come up in the block.
Still waiting for the 1008 gaskets to arrive and turns out I was using 318 headers so am in for a new set of headers to.
I have Ferrera stainless valves 11/32 stem, and the springs to suit cam, I bought the heads bare. Heads were assembled by a engine builder and he wants to come check preload etc when I bolt the heads on.
The old steel J heads only had 1.9 intake valves.

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Compression, You are going from a open chamber head to a closed chamber. You will want to measure compression ratio. How far are the pistons in the hole, flat tops? Also what do you have for exhaust manifolds. An A body stock 340 exhaust manifold style can hit the eddy head on the drivers side. Not sure what your ute has. Also alternator can hit the head. Not insurmoutable issues just things to keep in mind. Also they take a different head bolt/stud kit.
I cant remember what compression ratio engine builder said it was but thinking it was 9 to 1.
I was using extractors but they are 318 ones so am going to use 360 manifolds until I get a new set of headers sorted. I got a ARP head bolt kit and 1008 gaskets, things I didn't know I needed until afterwards.

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Those pistons look like some aftermarket lower compression 340 pistons.... could be standard bore, low compression 340 pistons with the 360 block bored out .040". But they ought to come right to the top of the bore at TDC. Those eyebrows look to be the 10 cc variety.

Can you very accurately measure from the deck down/up to the flat top of the pistons at the absolute highest point in the stoke and let us know? And are there any markings on the piston domes? Once that measurement is known, then the CR can be computed.

Not a ton of lift on the valves so not much to worry over there.

Cam is small...good for low/mid RPM torque. But that's another good reason to take the measurement requested to figure out the CR, and then make sure you are not moving too high for DCR with that small cam, and straying too close to detonation problems.
 
with that cam the 318 headers will work fine,new would only help at the top end where that cam is going to run out of breath anyway and might hurt low end
try them b4 you change
that cam should work fine with true 9:1 and plenty of lift for that duration compared to a lot of "white box" cams that only give you .420 or .440
I have run a similar cam in a 9:1 360 with ported stock heads- but with KB pistons .020 over
did you ever report how far down the pistons are or what hyper piston
? why not the KBs ?
if you do come up with the numbers NM9 will run the numbers for you
ask lunati where you intake closes at .006 I'm guessing around 56 ABDC they give you .050 timing for degreeing the cam but not the seat timing for figuring dynamic compression
 
Sorry for delay been pretty busy lately so have finally got the numbers off the pistons and measurement for how high they come up in the bore.
Pistons look to say
H405P .030
03 - 025 - 04 - C

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