Distributor gurus (curving)
Thread Starter
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Distributor gurus (curving)
recently bought a Summit ignition kit for my 67 Mulletmobile...
I have heard 18 initial and 36 total is what I want...opinions?
Has the billet dist (mech advance only), MSD box and coil.
358 ci, 10:1
750 DP, ported Team G
302 cfm Dart heads by Mamo
Solid roller 250/254. .670/.660 110
6" rods
T56 Trans, 4.11 rear, tires will be 25-27" tall
Car weight will be around 3200 possibly less.
Opinions?
I dont mind running a little better gas if needed but I built it to run on pump if possible; I imagine it would be hard to hear it ping once its running..
I have heard 18 initial and 36 total is what I want...opinions?
Has the billet dist (mech advance only), MSD box and coil.
358 ci, 10:1
750 DP, ported Team G
302 cfm Dart heads by Mamo
Solid roller 250/254. .670/.660 110
6" rods
T56 Trans, 4.11 rear, tires will be 25-27" tall
Car weight will be around 3200 possibly less.
Opinions?
I dont mind running a little better gas if needed but I built it to run on pump if possible; I imagine it would be hard to hear it ping once its running..
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I forget which advance curve I used on Ol' Red, but it's on the MSD dizzy box. IIRC, it was the quickest one that went flat at 36*. I set it up to get that 36* at 3000 and never even checked the initial. I figured if it kicked at the starter I'd just back it down a touch. So far, no problem.
Instructor
Joined: Apr 2004
Posts: 201
Likes: 1
From: Taunton Ma
Im not an expert but i thought that the inital was derived from the vaccumn can on the side of the distributor and the combination of the vaccumn and mechnical you would set to 36 or all in. In your case there is no vaccumn so how would you set the initial?
Le Mans Master
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
With the vacuum can disconnected and plugged and the RPM between 2500 and 3000 you want 36*, than you can let the motor idle and see what the initial is, than connect the vacuum can. This is just a starting point you may have to adjust the timing a few degrees more or less after this. See the sticky at the top. PG.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
It depends what bushing is in the dist. if it's the 18 deg bushing then you set it for 36deg at 3000RPM and you have 18 degs at idle, if it's another bushing then you idle advance will be different.
The springs control the actual curve or how fast or slow the dist advances timing. You need the assortment of springs and the curve chart to do that properly
The springs control the actual curve or how fast or slow the dist advances timing. You need the assortment of springs and the curve chart to do that properly
Le Mans Master
Joined: Nov 2008
Posts: 5,691
Likes: 12
From: columbus oh
It depends what bushing is in the dist. if it's the 18 deg bushing then you set it for 36deg at 3000RPM and you have 18 degs at idle, if it's another bushing then you idle advance will be different.
The springs control the actual curve or how fast or slow the dist advances timing. You need the assortment of springs and the curve chart to do that properly
The springs control the actual curve or how fast or slow the dist advances timing. You need the assortment of springs and the curve chart to do that properly
.....
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Performance motors like allot of initial timing. I set my mechanical to 15 degrees. So with an initial of 18 I end up with about 33 total and I have the vacuum advance set to a max of 6.
That is allot of cam for a little 358 ci. Are you planning on an 8000 rpm red line?
That is allot of cam for a little 358 ci. Are you planning on an 8000 rpm red line?
Thread Starter
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Plan on shifting somewhere between 68-7200 with 7500 as a redline.
Modeled it to an extent after the Busch series motors....kinda.
Just like to wind em up a little.
No vacuum can on the distributor fwiw, I doubt this motor would make much.
Modeled it to an extent after the Busch series motors....kinda.
Just like to wind em up a little.
No vacuum can on the distributor fwiw, I doubt this motor would make much.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
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