Vac and Timing?
Thread Starter
|
Posting Guru
Joined: Jul 2003
Posts: 1,268
Likes: 0
From: Eureka, Ca.
Vac and Timing?
Can you use the vac to set timing like you do to set the carb?
Highest Vac = best Air/Fuel ratio.
Highest Vac = best timing?
Or am I way off base on this one?
Highest Vac = best Air/Fuel ratio.
Highest Vac = best timing?
Or am I way off base on this one?
Thread Starter
|
Posting Guru
Joined: Jul 2003
Posts: 1,268
Likes: 0
From: Eureka, Ca.
I guess I should give some more info.
complete Edel Perf RPM Power package. 9.68:1 CR,Locked out dist. MSD 6AL box and MSD Timing advance Computer. Total timing is easily set to whatever I want.
The problem is this motor doesn't like stock timing. I am wanting the best timing for My setup.
complete Edel Perf RPM Power package. 9.68:1 CR,Locked out dist. MSD 6AL box and MSD Timing advance Computer. Total timing is easily set to whatever I want.
The problem is this motor doesn't like stock timing. I am wanting the best timing for My setup.
Lead Driver
Joined: Apr 2001
Posts: 6,175
Likes: 21
From: Texas
Randy,
no surprise here. Non stock motors don't like stock timing. More and more I hear of guys at this forum who are running quite a bit more initial advance due to the bigger cams.
I'm going to set mine where it runs best, and avoids pinging on the top end. I'll be pretty close to 20 BTDC intial.
no surprise here. Non stock motors don't like stock timing. More and more I hear of guys at this forum who are running quite a bit more initial advance due to the bigger cams.
I'm going to set mine where it runs best, and avoids pinging on the top end. I'll be pretty close to 20 BTDC intial.
Thread Starter
|
Posting Guru
Joined: Jul 2003
Posts: 1,268
Likes: 0
From: Eureka, Ca.
Trending Topics
Post Fiend
Joined: Feb 2000
Posts: 5,130
Likes: 8
From: Brea CA
I see what you're doing now!
Yes, with your package you're gonna need a lot of initial while limiting the total. Then dial in the curve so it never pings at the lowest rpm's that will see WOT.
Yes, with your package you're gonna need a lot of initial while limiting the total. Then dial in the curve so it never pings at the lowest rpm's that will see WOT.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
Lead Driver
Joined: Apr 2001
Posts: 6,175
Likes: 21
From: Texas
I guess the key is to avoid pinging at all RPM levels. I guess you could have some very odd timing curve that would ramp too fast and have pinging somewhere in the timing curve aside from the max advance. But that seems unlikely. So, I think the basic idea is to watch the max advance and set the rest where you like it!
I'll be playing with that on my setup.
I'll be playing with that on my setup.
FTE Leadership Emeritus
Joined: Jul 2002
Posts: 42,561
Likes: 423
From: Long Island USA
I have my 10.9:1 (or so) 390 w/292/292 adv cam running at around 18 degrees at idle.
I have an adjustable vacuum advance hooked to MANIFOLD vacuum. Adjusted so that it's stiff, the idle is at around 18 BTDC. Hit the gas, timing retards down to 12-13, good low-end torque, no ping.
Dizzy is setup on the short advance side, 13 (cam) degrees, 26 crank. Two weak springs, keeps the mechanical from coming on too low, but gives more advance at higher RPMs.
Total advance doesn't get past about 35 (which is about right).
Funky, but it works great. So, yeah, 18-20 BTDC with a heavy cam seems to work - not sure for how long though
Nice thing about this setup is that when cranking, static timing is down around 10BTDC which is perfect.
IF your MSD can be setup like that, go for it - it's worth a try - but can you set crank advance different than idle? And you might want to back off on the advance at low RPM when hitting the gas - if that's possible with the MSD timing computer. Let us know!
I have an adjustable vacuum advance hooked to MANIFOLD vacuum. Adjusted so that it's stiff, the idle is at around 18 BTDC. Hit the gas, timing retards down to 12-13, good low-end torque, no ping.
Dizzy is setup on the short advance side, 13 (cam) degrees, 26 crank. Two weak springs, keeps the mechanical from coming on too low, but gives more advance at higher RPMs.
Total advance doesn't get past about 35 (which is about right).
Funky, but it works great. So, yeah, 18-20 BTDC with a heavy cam seems to work - not sure for how long though
Nice thing about this setup is that when cranking, static timing is down around 10BTDC which is perfect.
IF your MSD can be setup like that, go for it - it's worth a try - but can you set crank advance different than idle? And you might want to back off on the advance at low RPM when hitting the gas - if that's possible with the MSD timing computer. Let us know!