Polylocks to valve cover clearance
Thread Starter
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,321
From: Fleming Island, FL
Polylocks to valve cover clearance
Hi, I need to know does a roller rocker arm polylock style nuts fit under the 78-82 stock aluminum fin valve covers. I've taken some "rough" measurements and I've come up with 0.550 of a inch clearance between rocker stud to valve cover. My guestimating is telling me it close.
Thread Starter
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,321
From: Fleming Island, FL
I guess it's how the screw in stud bosses are machined. I don't think the height of the stud is going to be a problem. The fulcrum point of the rocker arm will always be at the same height, hence the polylock would remain constant.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Most Walmart toy section have a product called Silly Putty. Comes in a plastic egg.
With V.C gasket removed, and poly-lock torqued to zero lash on any valve, doesn't matter, place a gob of that putty on top of the nut.
Install V.C and press down. Remove V.C.
How much clearance (putty) do you have left?
Then adding the gasket thickness for a safety margin is your clearance.
Do you have Oil Drippers? I know some people grind them off. Which defeats the purpose.
With V.C gasket removed, and poly-lock torqued to zero lash on any valve, doesn't matter, place a gob of that putty on top of the nut.
Install V.C and press down. Remove V.C.
How much clearance (putty) do you have left?
Then adding the gasket thickness for a safety margin is your clearance.
Do you have Oil Drippers? I know some people grind them off. Which defeats the purpose.
Burning Brakes
Joined: Oct 2002
Posts: 1,040
Likes: 109
Actually his silly putty idea is probably the best idea & the cheapest
I have a motor that has roller rockers, stud girdles & locks, I bought a set of fabricated aluminum covers and (just guessing) need anywhere
from 3/8" to 1/2" additional clearance
My guess for yours is a BIG NO especially if you have the oil drippers
I have a motor that has roller rockers, stud girdles & locks, I bought a set of fabricated aluminum covers and (just guessing) need anywhere
from 3/8" to 1/2" additional clearance
My guess for yours is a BIG NO especially if you have the oil drippers
Drifting
Joined: Sep 2016
Posts: 1,492
Likes: 524
From: Ventura California
I used something similar to the silly putty. It’s silicone putty.
Mix a base and catalyst together, then do the same thing as the silly putty. Difference is that the silicone putty hardens and you can more easily measure
Mix a base and catalyst together, then do the same thing as the silly putty. Difference is that the silicone putty hardens and you can more easily measure
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Thread Starter
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,321
From: Fleming Island, FL
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Oh but it will.
It does not matter if you are measuring piston to valve clearance. Air cleaner to hood clearance or rocker arms nut to V.C.
These are all "blind" measurements that need a putty / clay imprint so you can visualize the clearances.
It does not matter if you are measuring piston to valve clearance. Air cleaner to hood clearance or rocker arms nut to V.C.
These are all "blind" measurements that need a putty / clay imprint so you can visualize the clearances.
Thread Starter
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,321
From: Fleming Island, FL
I really didn't want to publicly say what I'm planning but here it goes. Not to rag on the Crossfire, but TPI IMO is way better. So what I'm thinking is Flotek 180cc heads, a Comp Cam 12-388-4, TPI controled by a Megasquirt 2 for a nice mild 300HP. I have in my mind the visual appearance that's why I'm asking because the heads require roller rockers. I already have the TPI and the Megasquirt ready to go.
Burning Brakes
Joined: Oct 2002
Posts: 1,040
Likes: 109
SPACERS are available but you are still going to have to figure how thick of ones you will need. Keep in mind the oil drippers if your covers have them = I'd keep the drippers if possible or
make sure your oiling system is up to snuff
You aren't building something someone else hasn't built already, the more information you provide & figure out flaws BEFORE will make your project go much smoother.& less expensive.
With those runners you will get decent bottom end to mid range, not going to be a rocket ship.
build it your way and enjoy
Thread Starter
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,321
From: Fleming Island, FL
SPACERS are available but you are still going to have to figure how thick of ones you will need. Keep in mind the oil drippers if your covers have them = I'd keep the drippers if possible or
make sure your oiling system is up to snuff
You aren't building something someone else hasn't built already, the more information you provide & figure out flaws BEFORE will make your project go much smoother.& less expensive.
With those runners you will get decent bottom end to mid range, not going to be a rocket ship.
build it your way and enjoy
make sure your oiling system is up to snuff
You aren't building something someone else hasn't built already, the more information you provide & figure out flaws BEFORE will make your project go much smoother.& less expensive.
With those runners you will get decent bottom end to mid range, not going to be a rocket ship.
build it your way and enjoy
I have the valve covers off for a leak. I'm probably going to pull the engine. Sort of like a leaky faucet turns into a whole remodel.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
The short poly locks will fit......I have short poly's and LT-1 covers on my 82' Z/28....with the Comp magnum roller tip rocker.
I also have them on my 406....but the valve cover rail on most aftermarket heads is 1/2" taller......
Jebby
I also have them on my 406....but the valve cover rail on most aftermarket heads is 1/2" taller......
Jebby
Thread Starter
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,321
From: Fleming Island, FL
That's good to know. I just didn't want to buy all this stuff and end up having to use some sort of tall valve cover. I'm just very (well the word I'm looking for begins with A and we'll just leave it at that) fussy about certain things on my car. I looked at hundreds of valve covers online and nothing else appeals to me.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
That's good to know. I just didn't want to buy all this stuff and end up having to use some sort of tall valve cover. I'm just very (well the word I'm looking for begins with A and we'll just leave it at that) fussy about certain things on my car. I looked at hundreds of valve covers online and nothing else appeals to me.
Use studs and stainless nyloc nut with those $50 fel pro valve cover gaskets and it is forever......the $50 gaskets raise the cover up an 1/8" too.
Jebby
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
You can also get extra thick valve cover gaskets to gain you a little bit more room, and then use spacers as a "backup plan" if you need even more clearance than the extra thick gaskets provide. (The spacers are shockingly expensive for what they are, IMO.)
P.S. Nice to see another C3 TPI conversion! MegaSquirt is a geeky way to go with it, too.
Adam
P.S. Nice to see another C3 TPI conversion! MegaSquirt is a geeky way to go with it, too.
Adam
Thread Starter
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,321
From: Fleming Island, FL
What sold me on going with Megasquirt was I downloaded Tuner Studio just to check it out and right away I saw how user friendly it was compared to TunerPro that I used with the Moates stuff. After I built the kit I made a adapter harness to go from the Megasquirt to the car's two ECM plugs. I configure the Megasquirt for TBI and HEI/ESC. Connected it and to my amazement it started right up😃. I did a little tuning work and was convinced that Megasquirt was right for this build.
Thread Starter
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,321
From: Fleming Island, FL