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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Which Distributor?

  • Thread starter Thread starter 69Rcode_Mach1
  • Start date Start date Dec 20, 2011

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Dec 20, 2011
#1
  • Dec 20, 2011
  • #1
It is winter time which means the car is going under the knife again. I got new front suspension on the way, and need to decide on a distributor. I called MSD and they recommended this distributor to me. http://www.summitracing.com/parts/MSD-85805/ I understand the purpose of a vacuum advance but am wondering if with my setup it is necessary or not.

Now I told the guy my combo and he felt that it is not the most streetable thing in the world so I wouldn't benefit from having any vacuum advance. The guy kept talking like I used it as a strip car so I want your guys feedback. I understand the car is not the most tame, but it is used as a weekend cruiser not so much a drag car. Once I move down to the Southern California I plan to drive this car to and from work as much as possible. The only reason it's a weekend cruiser here is because of our winters.

Given that I will drive this on the street quite a bit, do you think I would benefit from something like this: http://www.summitracing.com/parts/MSD-83541/ or should I just stick with mechanical advance and call it good?

Open to all suggestions, but want an MSD distributor to go with my 6AL box. Thanks guys.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Dec 21, 2011
#2
  • Dec 21, 2011
  • #2
with the cam you are using, i would delete the vacuum advance as you really cant use it to its fullest effect, and it is one less thing to deal with when troubleshooting problems.
 

2vNotch

Active Member
Dec 6, 2011
519
21
29
Rogers, AR
Dec 21, 2011
#3
  • Dec 21, 2011
  • #3
+1
 

mtaqua

Member
Oct 7, 2006
345
4
19
Dec 22, 2011
#4
  • Dec 22, 2011
  • #4
mech adv, or lock it out. I've got a little more cam and head and run 34 degrees locked out. I have a programmable 6 box and tried running an advance program and the motor did much better locked out than with a ramp.
 

BuckeyeDemon

Member
Apr 13, 2010
130
9
19
Cincinnati, OH
Dec 23, 2011
#5
  • Dec 23, 2011
  • #5
shouldn't you be looking at the 8578 (mechanical) or 8478 (mechanical w/vacuum) if you already have a box?

if you get the one with the vacuum then you at least have the option to use it. big cams can lead to low vacuum at idle and with the option of the vacuum you can gain a little more advance at idle. locking your distributor to 30-34 may make it a little more difficult to start.

whatever you decide, make sure you read and understand about adjusting the bushings and springs. i doubt the base setup will be what you want.
 
G

grainboy

Member
Feb 2, 2006
140
0
17
Goodyear, AZ
Dec 23, 2011
#6
  • Dec 23, 2011
  • #6
After viewing this thread, I am seriously considering summits plug and play billet distributor for 179.
 

mtaqua

Member
Oct 7, 2006
345
4
19
Dec 23, 2011
#7
  • Dec 23, 2011
  • #7
mine did worse starting with timing pulled. Not that I have the same build. I'd spend the money and get the MSD.
 

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Dec 23, 2011
#8
  • Dec 23, 2011
  • #8
Yeah my mistake, I will be getting the one compatible with my box. Setting it up isn't an issue, I am doing 22 initial and totals up to 36 once it is all in by 3000. I will play with it once I get it back on the dyno. Just torn on whether the vacuum advance is worth having or not for a car that will be driven quite a bit, performance comes first, but more than 10mpg with a 5 speed would be nice.
 

BuckeyeDemon

Member
Apr 13, 2010
130
9
19
Cincinnati, OH
Dec 24, 2011
#9
  • Dec 24, 2011
  • #9
you'll need to order a special bushing to get 14 degrees of mechanical. they are available. just not from MSD. i think you'll find 36 will be a lot more than that engine wants.
 

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Dec 26, 2011
#10
  • Dec 26, 2011
  • #10
Yeah that's what I figured. I thought these engines like around 34-36 total timing?
 

mtaqua

Member
Oct 7, 2006
345
4
19
Dec 26, 2011
#11
  • Dec 26, 2011
  • #11
Probably somewhere between 32-36. Mine liked 34 the most, lost power either direction. Getting 8 MPG. 4.30's bigger heads, cam and 1100 dommy.
 
P

palerider94

Member
Feb 21, 2006
573
1
19
Dec 26, 2011
#12
  • Dec 26, 2011
  • #12
+ ive got the vacuum advance on my 347 set up and ended up capping the hose. I need to pull it out and lock it out one of these days. I was having some off idel acceleration issues. Thought it was carb but local engine builder was looking at my car and plugged - not more offi idle issues.
 
G

grainboy

Member
Feb 2, 2006
140
0
17
Goodyear, AZ
Dec 27, 2011
#13
  • Dec 27, 2011
  • #13
69Rcode_Mach1 said:
Yeah that's what I figured. I thought these engines like around 34-36 total timing?
Click to expand...
More like 34 total.
 

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Dec 28, 2011
#14
  • Dec 28, 2011
  • #14
I see, well looks like no vacuum advance it is. She'll just have to be an expensive daily driver.
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Dec 29, 2011
#15
  • Dec 29, 2011
  • #15
How much advance the motor likes depends on how good the combustion chamber and spark plug location is. I don't know about the Vic Jr. heads, but I would think modern heads with a good combustion chamber should like less than 34 degrees advance. I would expect 34 degrees with 60s or 70s iron heads, though.
 
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