logo
12 Port News - Features
12 Port History
Casting Numbers
Online Store
Tech Tips
Become a Member
Previous Thread
Next Thread
Print Thread
Rate Thread
#8232 06/30/05 12:40 PM
Joined: Dec 2004
Posts: 25
D
Active BB Member
OP Offline
Active BB Member
D
Joined: Dec 2004
Posts: 25
Hello,

I have a question about the valve adjustment of my '56 Canadian 261.

i got the engine running after i rebuild it, but the idle seems to be very rough. I did put in a new M4F cam with solids and tubular pushrods that i ordered at Patrick's. It also has new valves, .030 pistons/rings and newbearings
the crank was balanced and polished. for now i am using the stock intake and exhaust with the standard rochester 1 barrel. maybe that wil change in the future when i got the rest of my pproject sorted out.
so here is what i would like to know.
What is the right amount of valve lash and what is the easiest way to adjust i(enigine running or not)?
I did adjust them to the specs i have of a '54 261 before first startup and after the first warmup. It idle's around 450-500 rpm can i get it any slower than that? Can it be that i also have to advance the ignition beond the mark on the flywheel?

Thanks,

Dennis.

#8233 06/30/05 08:11 PM
Joined: May 2000
Posts: 243
J
Contributor
Offline
Contributor
J
Joined: May 2000
Posts: 243
Hi Dennis,
The M4F cam should have come with valve lash specs. Check the timing card that came with the cam.
Jim


Jim - #2130
#8234 07/01/05 06:25 AM
Joined: Sep 2003
Posts: 299
C
Contributor
Offline
Contributor
C
Joined: Sep 2003
Posts: 299
M4F Specs:

Intake 0,14
Exhaust 0,16
for heavy duty(racing/towing): exhaust 0,18

Warm it up (drive for a hlaf hour not just idle)
and do the valves while hot.

Set it to #1 firing position (tdc) and do:
1,3 and 5 exhaust and 1,2 and 4 intake

Set it to #6 firing position (tdc) and do:
6,4 and 2 exhaust and 6,5 and 3 intake.

Re check after 2000 mls.

your idle speed is O.K.

advance can change from stock with an 0.03 over engine and different cam. Also the gas is different from the one thy sold in the 50es, where the mark on the fly wheel was set. If you change carbs or exhaust you will see a difference to.

Advance it till it pings under load, tun it back slightly and you`r set. \:D

have fun!

Frank


To old to die young.
#8235 07/01/05 10:28 AM
Joined: Dec 2004
Posts: 25
D
Active BB Member
OP Offline
Active BB Member
D
Joined: Dec 2004
Posts: 25
Thanks Frank and Jim

That was exactly the info i needed, since the cam didn't came with any specs.

It seems i have my inlet to tight.
i had it set for .006 and the exhaust for .020 wich i found in the engine assembly manual.


Dennis.


Moderated by  stock49, Twisted6, will6er 

Link Copied to Clipboard
Who's Online Now
0 members (), 358 guests, and 49 robots.
Key: Admin, Global Mod, Mod
Newest Members
SSG Pohlman, castironphil, uncle dave, trustedmedications20, Jsmay101
6,786 Registered Users
Sponsored Advertisement
Sponsored Advertisement
This Space is Available
Powered by UBB.threads™ PHP Forum Software 7.7.5