Mr. Gasket 928 kit - spring weights?
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Mr. Gasket 928 kit - spring weights?
What is the order of this kits spring weights? I have silver, black and grey.
The springs in the distributor are on the far left and have a thicker gauge, but less coils.
Is there a method to stack two springs? I'm trying to get my advance to come in a bit later.
Lastly, what is the little brass fitting for?
The springs in the distributor are on the far left and have a thicker gauge, but less coils.
Is there a method to stack two springs? I'm trying to get my advance to come in a bit later.
Lastly, what is the little brass fitting for?
Race Director
Joined: May 2006
Posts: 18,727
Likes: 2,579
Black is lowest tension
Silver is middle
Gold is highest tension not sure why I dont see them in your picture, see link below.
https://www.summitracing.com/parts/m...SAAEgJbmPD_BwE
Try a combination of black and silver.
The bronze bushing is to replace the stock nylon bushing advance stop. The distributor has to be removed and disassembled to install.
The nylon bushing may or may not be still there.
Your total mechanical advance should be 36 degrees at about 2,800 to 3000 rpm.
Not sure what you mean by later, the stock springs are much stiffer and dont permit full advance at the rpm numbers above.
Are you using a dial back timing light to set maximum advance?
Silver is middle
Gold is highest tension not sure why I dont see them in your picture, see link below.
https://www.summitracing.com/parts/m...SAAEgJbmPD_BwE
Try a combination of black and silver.
The bronze bushing is to replace the stock nylon bushing advance stop. The distributor has to be removed and disassembled to install.
The nylon bushing may or may not be still there.
Your total mechanical advance should be 36 degrees at about 2,800 to 3000 rpm.
Not sure what you mean by later, the stock springs are much stiffer and dont permit full advance at the rpm numbers above.
Are you using a dial back timing light to set maximum advance?
Last edited by MelWff; Apr 18, 2020 at 05:38 PM.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Hey Mel,
This is that exact kit. It appears grey has replaced gold.
I have some detonation issues and I'm trying to delay advance a bit. I switched out the vacuum advance from the B28 to B26 as I'm trying to limit the range and degrees in which vacuum advance and centrifugal advance overlap.
This is that exact kit. It appears grey has replaced gold.
I have some detonation issues and I'm trying to delay advance a bit. I switched out the vacuum advance from the B28 to B26 as I'm trying to limit the range and degrees in which vacuum advance and centrifugal advance overlap.
Burning Brakes
Joined: Dec 2005
Posts: 1,164
Likes: 224
From: Pawleys Island, SC
I measured the spring tension of a few advance spring and cam kits during the process of setting my ignition advance. In the Mr. Gasket 928 kit the silver and black springs were essentially identical, 56oz and 57oz, respectively. The gold spring was 72oz.
If you are looking for a heavier spring, the Mr.Gasket 929 kit gold spring is the next highest I found at 105oz. In the same 929 kit the black was 23oz and the silver was 115oz.
The next lighter springs I found were the gold springs in both the the Spectre and Jegs kits at 34oz.
My final configuration was the Moroso kit advance springs and cam, using the lightest two Moroso springs in the kit ('bronze', 30oz pull tension)
If you are looking for a heavier spring, the Mr.Gasket 929 kit gold spring is the next highest I found at 105oz. In the same 929 kit the black was 23oz and the silver was 115oz.
The next lighter springs I found were the gold springs in both the the Spectre and Jegs kits at 34oz.
My final configuration was the Moroso kit advance springs and cam, using the lightest two Moroso springs in the kit ('bronze', 30oz pull tension)
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Originally Posted by revitup
I measured the spring tension of a few advance spring and cam kits during the process of setting my ignition advance. In the Mr. Gasket 928 kit the silver and black springs were essentially identical, 56oz and 57oz, respectively. The gold spring was 72oz.
If you are looking for a heavier spring, the Mr.Gasket 929 kit gold spring is the next highest I found at 105oz. In the same 929 kit the black was 23oz and the silver was 115oz.
The next lighter springs I found were the gold springs in both the the Spectre and Jegs kits at 34oz.
My final configuration was the Moroso kit advance springs and cam, using the lightest two Moroso springs in the kit ('bronze', 30oz pull tension)
If you are looking for a heavier spring, the Mr.Gasket 929 kit gold spring is the next highest I found at 105oz. In the same 929 kit the black was 23oz and the silver was 115oz.
The next lighter springs I found were the gold springs in both the the Spectre and Jegs kits at 34oz.
My final configuration was the Moroso kit advance springs and cam, using the lightest two Moroso springs in the kit ('bronze', 30oz pull tension)
Drifting
Joined: Aug 2019
Posts: 1,510
Likes: 498
If the timing change looses to much power or don’t work try some VP Racing Octanium octane booster , this stuff works and you might only need a few ounces at fill up , local stores like Autozone and O’Reilly’s have it in stock
https://www.jegs.com/i/VP+Racing+Fue...CABEgInl_D_BwE
https://www.jegs.com/i/VP+Racing+Fue...CABEgInl_D_BwE
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Originally Posted by Eric P
If the timing change looses to much power or don’t work try some VP Racing Octanium octane booster , this stuff works and you might only need a few ounces at fill up , local stores like Autozone and O’Reilly’s have it in stock
https://www.jegs.com/i/VP+Racing+Fue...CABEgInl_D_BwE
https://www.jegs.com/i/VP+Racing+Fue...CABEgInl_D_BwE
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2020 C3 of the Year Finalist - Modified
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You dont need later advance you need lower total advance or increase octane, or lower the engine temps
hers a good read https://www.hotrod.com/articles/hppp...ne-detonation/
https://help.summitracing.com/app/an...ine-detonation.
I hope its an easy fix
hers a good read https://www.hotrod.com/articles/hppp...ne-detonation/
https://help.summitracing.com/app/an...ine-detonation.
I hope its an easy fix
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Forget trying to put a bandage on. Your real problem is your too small of duration cam for the rest of your engine build.
You have exceeded 8.3 or 8.4 Dynamic Compression Ratio.
When I was younger and I built my first 383 and didn't want to go overboard with the cam lobes. So I installed a 232/238@ .050 along with aluminum heads and 10.7 or so static compression ratio. I had serious rattle/ pinging going down the road. I tried every bandage. The fix was to install a new cam with more duration
You have exceeded 8.3 or 8.4 Dynamic Compression Ratio.
When I was younger and I built my first 383 and didn't want to go overboard with the cam lobes. So I installed a 232/238@ .050 along with aluminum heads and 10.7 or so static compression ratio. I had serious rattle/ pinging going down the road. I tried every bandage. The fix was to install a new cam with more duration
Last edited by gkull; Apr 19, 2020 at 10:08 AM.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Originally Posted by gkull
Forget trying to put a bandage on. Your real problem is your too small of duration cam for the rest of your engine build.
You have exceeded 8.3 or 8.4 Dynamic Compression Ratio.
When I was younger and I built my first 383 and didn't want to go overboard with the cam lobes. So I installed a 232/238@ .050 along with aluminum heads and 10.7 or so static compression ratio. I had serious rattle/ pinging going down the road. I tried every bandage. The fix was to install a new cam with more duration
You have exceeded 8.3 or 8.4 Dynamic Compression Ratio.
When I was younger and I built my first 383 and didn't want to go overboard with the cam lobes. So I installed a 232/238@ .050 along with aluminum heads and 10.7 or so static compression ratio. I had serious rattle/ pinging going down the road. I tried every bandage. The fix was to install a new cam with more duration
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
You can even try advancing the cam 2 or 4degrees
What are your cam specs @ .050 and your C/R
Le Mans Master
Joined: Mar 2004
Posts: 7,493
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From: Little Rock AR
Too much DCR shows up at lighter throttle out cruising at highway speeds. I tried retarding timing and the crane came adjustable vacuum can. Octane boosters.... detonation even when you can't hear it is very hard on the engine.
You can even try advancing the cam 2 or 4degrees
What are your cam specs @ .050 and your C/R
You can even try advancing the cam 2 or 4degrees
What are your cam specs @ .050 and your C/R
Do not fall into the DCR trap applying it on a GM cam. The recomended DCR will not work on a GM slow ramp cam. The recomendations are from empirical evidence using typical aftermarket cams.
George - We have another thread on this particular engine. Bottom line - The C/R is not the issue but quench is bad and cam is too far advanced.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Guys,
Went with the grey springs and B26 vacuum advance. Centrifugal advance is 36° all in at 3500 RPM. Idle is excellent and throttle very responsive and no more detonation at any performance point. Very snappy motor off the line, I'm sure I've lost much off the top, but that's fine, 0-4000 is where I'll live 99% of the time.
Went with the grey springs and B26 vacuum advance. Centrifugal advance is 36° all in at 3500 RPM. Idle is excellent and throttle very responsive and no more detonation at any performance point. Very snappy motor off the line, I'm sure I've lost much off the top, but that's fine, 0-4000 is where I'll live 99% of the time.
Last edited by LeMans Pete; Apr 20, 2020 at 09:15 PM.
