timing marks
November 23rd, 2010, 10:33 PM
#1
Registered User
Thread Starter
Join Date: Dec 2008
Posts: 173
timing marks
Timing just doesnt seem right on my 403. I found two different examples of the timing marks. I have found crank 12 cam 6 ( rotor pointing at cylinder #6)
crank 12 cam 6 rotor pointing at cylinder #1 (like chevy 350) So which is it? Also does piston have to be at TDC of compression or exhaust stroke? Intake is currently off so couldn't i just just spin it over until both valves fully close? Heres a link to a site forum where they decided the rotor pointed at #6: http://www.ls1lt1.com/forum/showthread.php?t=27823
crank 12 cam 6 rotor pointing at cylinder #1 (like chevy 350) So which is it? Also does piston have to be at TDC of compression or exhaust stroke? Intake is currently off so couldn't i just just spin it over until both valves fully close? Heres a link to a site forum where they decided the rotor pointed at #6: http://www.ls1lt1.com/forum/showthread.php?t=27823
Last edited by dman0712; November 23rd, 2010 at 10:37 PM.
November 24th, 2010, 05:13 AM
#2
Registered User
Join Date: Sep 2010
Location: Shorewood, Il.
Posts: 3,057
I don't see the problem - install the timing chain and gears as pictured, button it up, start the car, set the timing, and drive away! Done!!
Shoud start aimed at number 1 - without a probem!
If you changed cam + lifters, make sure you've used the proper lube and used oil with zinc, so it doesn't 'wipe out'!
If you didn't change the cam, most 'pollution' cams were ground with as much as 10 degrees retard from the factory, back then.
A cheap and basically undetectable horsepower gain would be to buy a Cloyes timing set, and advance the cam the 6 degrees they allow.
I did it once a few years ago, and there was a definate 'seat of the pants' feel, but the old chain was bad!
And make sure you change the water pump, as every one I've done needed a pump soon thereafter!
Seems while out, the seal dries and cracks, and the $25 spent means you don't have to tear it down, again.
Shoud start aimed at number 1 - without a probem!
If you changed cam + lifters, make sure you've used the proper lube and used oil with zinc, so it doesn't 'wipe out'!
If you didn't change the cam, most 'pollution' cams were ground with as much as 10 degrees retard from the factory, back then.
A cheap and basically undetectable horsepower gain would be to buy a Cloyes timing set, and advance the cam the 6 degrees they allow.
I did it once a few years ago, and there was a definate 'seat of the pants' feel, but the old chain was bad!
And make sure you change the water pump, as every one I've done needed a pump soon thereafter!
Seems while out, the seal dries and cracks, and the $25 spent means you don't have to tear it down, again.
Last edited by Rickman48; November 24th, 2010 at 05:18 AM.
November 24th, 2010, 05:55 AM
#4
Registered User
Join Date: Nov 2008
Location: Central Fl
Posts: 7,971
X2 Nick.
The rotor will point to #6 when the crank gear is at 12 and the cam is at 6. The rotor will point to #1 when the crank gear is at 12 and the cam gear is at 12.
Rickman- I believe he has a roller cam, no break in needed. How would you know to advance it 6 degrees if you don't check it. Don't assume, check it.
The rotor will point to #6 when the crank gear is at 12 and the cam is at 6. The rotor will point to #1 when the crank gear is at 12 and the cam gear is at 12.
Rickman- I believe he has a roller cam, no break in needed. How would you know to advance it 6 degrees if you don't check it. Don't assume, check it.
Last edited by cutlassefi; November 24th, 2010 at 05:58 AM.
November 24th, 2010, 09:04 AM
#5
Registered User
Thread Starter
Join Date: Dec 2008
Posts: 173
That answers my question and hopefully solves my problem. I have crank gear at 6 and cam gear at 12 and my rotor points at #1. I will point it at #6 and see what happens
Last edited by dman0712; November 24th, 2010 at 09:54 AM.
Thread
Thread Starter
Forum
Replies
Last Post
