Still Fixing timing, Help!
Thread Starter
Instructor
Joined: Dec 2007
Posts: 245
Likes: 2
From: Jersey shore NJ
Still Fixing timing, Help!
Hi guys, this is an update to my last thread.
This is what I have going on with my stock HEI.
I'm only getting 16 degrees mechanical. I've checked and its not getting hung up. It only gives 16 degrees?
so I have to set Initial at 20 degrees to get 36 total.
Next problem is that its all in by 1500 RPM ( with stock springs). I bought a new spring kit but all of the springs are softer than my stock springs so it brings the full advance in even earlier.
My vacuum can is only giving me 9 degrees, ( i can fix this with an adjustable one). so right now I'm sitting at 47 degrees with vacuum.
Whats wrong?
This is what I have going on with my stock HEI.
I'm only getting 16 degrees mechanical. I've checked and its not getting hung up. It only gives 16 degrees?
so I have to set Initial at 20 degrees to get 36 total.
Next problem is that its all in by 1500 RPM ( with stock springs). I bought a new spring kit but all of the springs are softer than my stock springs so it brings the full advance in even earlier.
My vacuum can is only giving me 9 degrees, ( i can fix this with an adjustable one). so right now I'm sitting at 47 degrees with vacuum.
Whats wrong?
Thread Starter
Instructor
Joined: Dec 2007
Posts: 245
Likes: 2
From: Jersey shore NJ
ok, Another update!
I was reading one of Lar's old papers and he said most stock HEI distibutors will only give you about 15 to 18 degrees of mechanical advance. ( i'm getting 16 so maybe i'm good).
But, it sounded like you need to alter the weights to get more advance so you do not need to set Initial at 20 degrees. ( to get 36 total)
I was thinking of filing down the edge of the weights that stop them from opening more to try and get them to give me a few more degrees. Has anyone done this ???
I was reading one of Lar's old papers and he said most stock HEI distibutors will only give you about 15 to 18 degrees of mechanical advance. ( i'm getting 16 so maybe i'm good).
But, it sounded like you need to alter the weights to get more advance so you do not need to set Initial at 20 degrees. ( to get 36 total)
I was thinking of filing down the edge of the weights that stop them from opening more to try and get them to give me a few more degrees. Has anyone done this ???
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Under the plate the weights set on there's a pin in a slot. That's where you'll get more mechanical advance. Here is a link to MSD's Pro Billet. Look down thru the pages and you can see how MSD did the advance stop.
http://www.msdignition.com/instructi...ve+distributor
http://www.msdignition.com/instructi...ve+distributor
Thread Starter
Instructor
Joined: Dec 2007
Posts: 245
Likes: 2
From: Jersey shore NJ
Thanks Tim, Thats what Gordon suggested also, I am going to look at the pin now to see if I have more room to work with. I would Like to another 2 degrees out of my mechanical so I can drop my Initail timing down to 18 degrees from the 20 I have it at now.
Thread Starter
Instructor
Joined: Dec 2007
Posts: 245
Likes: 2
From: Jersey shore NJ
OK another update,
I checked the slots in the bottom plate and there is plenty of room for the mechanical advance to move more , but the weights are maxing out and stop when they hit the center plate as they should.
I checked the slots in the bottom plate and there is plenty of room for the mechanical advance to move more , but the weights are maxing out and stop when they hit the center plate as they should.
Burning Brakes
Joined: Dec 2007
Posts: 952
Likes: 0
That's what they do. Change the springs to a pair of gold springs from a Mr gasket 928G.
Thread Starter
Instructor
Joined: Dec 2007
Posts: 245
Likes: 2
From: Jersey shore NJ
I do not think the springs are the problem now. The weights are opening fully until they hit the center plate and stop. they will not open any more. My stock springs are giving me full advance at 1500 RPM, if I use the gold springs it comes in even earlier.
Racer
Joined: Mar 2006
Posts: 366
Likes: 1
From: Houston Texas
My weights are stock w/106 stamped on them. The gold spring brings advance all in at ~2500. NAPA shows 106 weights in their catalog.
http://www.napaonline.com/NOLPPSE/(S...114_0000999999
See 2nd view for stamped number.
http://www.napaonline.com/NOLPPSE/(S...114_0000999999
See 2nd view for stamped number.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski