advance bushings?
Thread Starter
Burning Brakes
Joined: Apr 2008
Posts: 825
Likes: 40
From: Glasgow, Scotland
advance bushings?
Ive got new mallory dizzy, ive got a 21 degree bushing in at present, ive got my intial timing set at 15 degrees, so add these 2 up and my total is 36 degrees?
when I check my total, dial in 36 on timing gun, give it 3000rpm, thats when its all in, I can see on my balancer wheel that im about 10 degrees short, so put in 21 degrees into gun and it lines up to the zero mark tdc, so why cant I get my 36?
any idea's
cheers
dave
when I check my total, dial in 36 on timing gun, give it 3000rpm, thats when its all in, I can see on my balancer wheel that im about 10 degrees short, so put in 21 degrees into gun and it lines up to the zero mark tdc, so why cant I get my 36?
any idea's
cheers
dave
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
First, the bushings are approximate only and not exact on the degrees.
Second, if you really do have all-in at 3000, you will have some advance coming in at idle, thus shortening your effective curve. Set total for 36 and disregard initial as long as it's in a range of 16-24 degrees.
Second, if you really do have all-in at 3000, you will have some advance coming in at idle, thus shortening your effective curve. Set total for 36 and disregard initial as long as it's in a range of 16-24 degrees.
Thread Starter
Burning Brakes
Joined: Apr 2008
Posts: 825
Likes: 40
From: Glasgow, Scotland
First, the bushings are approximate only and not exact on the degrees.
Second, if you really do have all-in at 3000, you will have some advance coming in at idle, thus shortening your effective curve. Set total for 36 and disregard initial as long as it's in a range of 16-24 degrees.
Second, if you really do have all-in at 3000, you will have some advance coming in at idle, thus shortening your effective curve. Set total for 36 and disregard initial as long as it's in a range of 16-24 degrees.
whats your thoughts on changing my bushing size, ive got 28, 25, 21, and 18, if I changed to a smaller bush, that would give me a longer curve?
is 28 the smallest one in my range?
thanks
dave
Last edited by corvettedave383; Oct 7, 2008 at 02:25 PM.
Thread Starter
Burning Brakes
Joined: Apr 2008
Posts: 825
Likes: 40
From: Glasgow, Scotland
Update
I tried setting the timing to 36 total, I then end up with about 27 for intial!, and the engine doesnt seem happy at that atall
so I changed the advance bushing from a blue 21 degree to a red 28 degree(smallest)
I set timing to 36, and my intial now falls in at about 22 degrees, and timing all in by 3000 rpm, using 2 blue springs on weights, the engine seems alot happier!
thanks
dave
so I changed the advance bushing from a blue 21 degree to a red 28 degree(smallest)
I set timing to 36, and my intial now falls in at about 22 degrees, and timing all in by 3000 rpm, using 2 blue springs on weights, the engine seems alot happier!
thanks
dave
