Re: Eddy RPM heads and stock rocker assembly
[Re: GregY]
#1308333
09/21/12 06:14 PM
09/21/12 06:14 PM
|
Joined: Jan 2003
Posts: 1,263
Southwestern Ontario Canada
racealittle
pro stock
|
pro stock
Joined: Jan 2003
Posts: 1,263
Southwestern Ontario Canada
|
Been working for me. Everything seems to fit and clear. Never gave it another thought.
Too many cars, too many parts, too little coin, too little space to work in, too little time left to make it all happen!
Update: down to one ride, still too many parts, a little more jingle in the pocket, gaining space, and it's going to happen this year!
|
|
|
Re: Eddy RPM heads and stock rocker assembly
[Re: radar]
#1308335
09/21/12 10:04 PM
09/21/12 10:04 PM
|
Joined: Jul 2003
Posts: 3,378
Rancho Cordova, CA
Exit1965
master
|
master
Joined: Jul 2003
Posts: 3,378
Rancho Cordova, CA
|
Good point on the preload.
It will depend on many things, the head gaskets, block, heads, cam, lifters.
The preload can be easily checked by putting a piece of tape on the pushrod and marking it with the shaft tightened 1) with the slack taken out and 2) fully, which should put preload on the lifter. The difference is the amount of preload.
Definitely check it. I had too much and it was causing valvetrain noise, and probably a performance decrease too. Up to about .070" is OK from what I read.
If the preload is OK, yes that cam will work fine with stock rockers. I am using a .509 cam with stock rockers and eddy heads on a 440.
|
|
|
Re: Eddy RPM heads and stock rocker assembly
[Re: Exit1965]
#1308336
09/22/12 10:44 AM
09/22/12 10:44 AM
|
Joined: Jul 2003
Posts: 3,378
Rancho Cordova, CA
Exit1965
master
|
master
Joined: Jul 2003
Posts: 3,378
Rancho Cordova, CA
|
You should measure the preload when the valve is fully closed. If you spin the engine to TDC of the power stroke of a cylinder, both valves will be closed.
It's probably better to check at least 1 cylinder on each side, but one side might do.
For #1, rotate the engine towards the point where you can't move or spin the intake pushrod, and the exhaust pushrod spins. Keep rotating towards the 0 mark on the balancer/timing cover, when you get there, both pushrods should spin since both valves are closed.
When I measured, I used a piece of blue painter's tape on the pushrod, and used the surface where the valve cover attaches, as the marking point where I used a razor blade (just the blade, so it sits flat against the head surface) to put a soft mark in the tape. Do it once where everything is torqued down, and once where you have just tightened to the point that the pushrod doesn't freely move up and down. The difference is the preload on the lifter.
Even a non primed lifter will have a spring hard enough that the pushrod can sit on the seat without pushing it down any.
Last edited by Exit1965; 09/22/12 10:49 AM.
|
|
|
Re: Eddy RPM heads and stock rocker assembly
[Re: Exit1965]
#1308337
09/22/12 11:10 AM
09/22/12 11:10 AM
|
Joined: Jan 2003
Posts: 1,194
Rochester, New York
GregY
OP
super stock
|
OP
super stock
Joined: Jan 2003
Posts: 1,194
Rochester, New York
|
Quote:
Do it once where everything is torqued
down, and once where you have just tightened to the point that the pushrod doesn't freely move up and down.
Okay, this is part that is still confusing me.
When you say "tightened to the point the pushrod doesn't freely move up and down" , does that mean I am loosening the rocker arm, then tightening to some point less than fully torqued?
Sorry, this is my first motor, I can't afford to screw it up
|
|
|
Re: Eddy RPM heads and stock rocker assembly
[Re: GregY]
#1308338
09/22/12 11:17 AM
09/22/12 11:17 AM
|
Joined: Jan 2003
Posts: 75,043
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 75,043
U.S.S.A.
|
Quote:
Sorry, this is my first motor, I can't afford to screw it up
then get or make a checking pushrod , if you have a hollow pushrod you can cut it , tap the inside and put a fully threaded stud and 2 nuts to adjust the pushrod length which is a hell of a lot easier, and more ACCURATE, than trying to not fully seat the rocker system.
|
|
|
Re: Eddy RPM heads and stock rocker assembly
[Re: GregY]
#1308339
09/22/12 01:03 PM
09/22/12 01:03 PM
|
Joined: Jul 2003
Posts: 3,378
Rancho Cordova, CA
Exit1965
master
|
master
Joined: Jul 2003
Posts: 3,378
Rancho Cordova, CA
|
Quote:
Quote:
Do it once where everything is torqued
down, and once where you have just tightened to the point that the pushrod doesn't freely move up and down.
Okay, this is part that is still confusing me.
When you say "tightened to the point the pushrod doesn't freely move up and down" , does that mean I am loosening the rocker arm, then tightening to some point less than fully torqued?
Sorry, this is my first motor, I can't afford to screw it up
Yes exactly- one measurement is taken at the first point that all the slack is out (no up/down movement, but it should still spin fairly easily). The 2nd measurement is when everything is torqued down. The difference on the 2 marks in the tape is the preload.
|
|
|
|
|
