pertronix ignition gaps

[Anonymous]

What is the best gap size to use with the pertronix flamethrower coil? its 40,000 watts and i remember reading that the gaps could be increased. but to how much? i have the pointless ignition, 7mm wires and 40,000 watt coil? also i was wondering if anyone knew of a place to get colored wires and hoses and all that stuff? trying to trick out the engine appearence a little. any knowledge is so greatly appreciated.

Thank you all
Scott

 

[MandarinaRacing]

Scott Hi...start with 0.040" that should work fine, tried going a little bit further than that and it don't work. I you set up to an MSD and DII you could probably get awy with as much as 0.060".

Alex

 

[Anonymous]

Whats up Alex
What is The MSD and DSII? i've heard a lot about it but not sure what it is, or where to get it. Any ideas would help out a lot. Also do you know of anyway to get rid of the vaccuum advance? i was talking to a guy who said that with a good electronic distributor i could do away with the vaccuum advance. What do you think. Truth? or Blarney?

Thanks for the knowledge
Scott

 

[Anonymous]

I gapped my plugs at .042 on my Mustang. I'm running a weber 38(produces more fuel, so more gap). On my falcon I gapped them at .040 with a stock motor. Both run good with those gaps.


David 8)

 

[CobraSix]

Question #1: When I ran that same set up, I gapped to .040-.042. Worked well.

Question #2: What is MSD and DS2? MSD is an ignition module. Give multiple sparks and generally more energy per spark. Very nice addition. Can be added to Pertronix equipped cars. DS2 is short for Duraspark 2. It is the ignition that came on 200/250 cars in the late 70s. It is similar to Pertronix, but is a little more reliable and easier to find system. The swap to an older 200/250 is very easy. I just completed the swap and it is well worth it. With my MSD Digital 6+ and DS2 with 8mm wires, I opened my gap to .052. Runs very nice and smooth now. I also no longer carry spare points in the back of my car incase the pertronix dies since I no longer have it. I'll be posting a how too on DS2 in a couple of days.

Question #3: Getting rid of vacuum advance. I've seen two ways to do this. #1: Cheap way, 90% solution: Plug the vacuum port, and with a timing light, find out how much total advance you are getting at 3000 RPM. Should be around 32-36* BTDC and you need to replace the mechanical advance springs with different springs if you are much outside of that range.
#2: Expensive way, 99.9% solution: MSD Digital Ignition Controller. You lock out your dizzy to have no mech or vac advance. Basically you set your dizzy for your total advance of around 34* BTDC. This controller (different from MSD Ignition I mentioned earlier) has a completely progammable timing curve. You can program it with a PC Laptop. MSD also make a less complicated and less expensive timing curve controller, but all it does is a simple linear timing curve with little adjustments.

Digital Ignition Controller: $380
Timing Controller: $200

Here is the the website with the two different controllers:
http://www.msdignition.com/n2000a.htm
http://www.msdignition.com/tc_3.htm

Good luck.

Slade

 

[Anonymous]

Slade,

you mentioned that you had to carry spare points around when you had the pertronix system. but i was under the impression that the ignitor was supposed to get rid of the points? whats up with that?

 

[Asa]

Scotts68: in case the petronix messes up, you can swap in the old points system and still get home

 

[Anonymous]

are the pertronix systems that unreliable?

 

[Asa]

nope, not at all, in fact all my experience has shown that they are the opposite

we are just a bit paranoid here 'bout our cars

 

[CobraSix]

I had my pertronix fail withint 2 weeks of initial install, but it was no fault of pertronix, I didn't know that the green tape was supposed to be there until after I had pulled some of it off. Points are just to keep from getting stuck in the middle of no where. Murphy's law.

My pertronix ran for a year with no problems what so ever.

Slade

 

[Anonymous]

Hi Guy's

At the risk of sounding unkind I need to comment on a couple of the above items.

1. The DS2 is not easier to get than the Pertronix.
2. The DS2 + MSD represents a major investment vs. conversion of a standard dual advance system, at least twice.
3. The performance of the DS2 is NOT materially different.
4. The Pertronix unit is very reliable when properly installed, which takes about 20 to 30 mins.
5. Springs do NOT control advance in a mechanical advance unit.
6. Elimination of the vac system by caping it is NOT in any way create an inferior system.

I think we all have an obligation to work toward offering facts on this forum. Opinion should be offered as such.

Steve

 

[CobraSix]

Steve,

In the spirit of opinions...of which of 99% of all posts here are:

1) I got a DS2 stuff over the counter at Autozone. I had to order my pertronix and wait for 3 days to get it. now if my pertronix fails, then I have to wait again. If my DS2 fails...I go to Autozone.

2) I never mentioned DS2/MSD as being cheap.

3) I disagree...my DS2 runs much smoother then Pertronix. Pertronix still ran much better then points. I would know, I just did the swap...

4) You are right...pertronix is generally reliable. But if you venture out of this forum, you will find problems with it. Though not frequent, they do occur more often then DS2 or points failures. Many of the V-8ers swapped to duraspark as well.

5 & 6) Springs DO help control the amount of advance. The springs are there to counter the centrifugal force of the mechanical advance weights. Mechanical advance works by spinning of weights as the dizzy speeds up. The springs counter that force and help keep the advance curve at a certain location. The Vacuum advance helps that. If you remove the vacuum advance, you remove part of the equation the dizzy relies upon. Sure you can get by by just advancing the dizzy to around 18* BTDC so your full advance is still achieved, but I dont' want to run 18* BTDC at idle.

DISCLAIMER: THESE VIEWS ARE EXPRESSED AS FACTS TO THE BEST OF MY KNOWLEDGE. BEING THAT I DO NOT KNOW EVERYTHING, TAKE THEM AS THAT, THEY MAY JUST BE OPINIONS...THEY ARE FACTS THAT I HAVE FOUND THROUGH MY OWN RESEARCH AND EXPERIENCES. THEY MAY DIFFER FROM YOURS...WHICH MAKES THEM ALL OPINIONS...

Slade

 

[Kstang]

i dont know about 1-4 as i have stock ingition as of now(indecicive) but i second the Facts that cobra six posted on numbers 5&6.

 

[Anonymous]

Last comment.

You are misinformed regarding items 5&6. The springs control the rate of advance change, not the amount. The amount is regulated by the stop cut into the weight. As for vac vs. centifugal advance, they are unrelated and used for different purposes. One cannot assume the operation of the vac advance dizzy represents the operation of the dual advance unit. The argument made is, however, approximately correct when related to the dual vac units.

As for the balance of your comments, in my opinion you are comparing apples to oranges. A dual vac dizzy converted to electronic via the original technology Ignitor (your system) probably is not as strong a performer as the DS2. However, the correct comparo is the Ignitor 2 and FlameThrower 2 with the ballast resistor removed.

Steve

 

[CobraSix]

Yes, vac and mech advance are for different purposes...mech advance is for speed of engine, vac advance for load purposes, so if the car is under RPMed, the engine can still get the needed advance for the load.

I am NOT, and have NEVER run a dual vac advance. I've always had vac/mech advance systems on my car and I do not have any ballast resistor. Did I compare Ignitor 2? No...because I have no experience with that and it wasn't asked.

the RATE of advance is just as important as the amount of advance. You generally don't want to be at full advance at 2000 RPM. That is why you may need tol recurve the dizzy. The vacuum above 1000 RPM (when the ported vacuum should start to operate) helps advance the dizzy. If you remove that help, then you are not getting the correct advance. That means you have to start your dizzy at 18-20*BTDC. Yes, people on this forum have done that with no problems...but I prefer to keep mine closer to stock specs around 8-10* BTDC. If you had read my post properly, I may have not used the 100% correct terms, but I explain that vac helps control the amount of advance. I never said it sets the advance. READ my ENTIRE post.

Steve, you are right that the springs do not control the ENTIRE advance, that is the weights and stops. Springs merely control the amount (or excuse me, rate) of advance at other points.

If you get rid of the vacuum advance and just go Mechanical, then yeah, you should be fine, but you have to make adjustments. They are to either recurve the dizzy with new springs or advance the dizzy to the point where you reach full advance at 3000 RPM. In my opinion, the second option is not a 100% solution, it is a 90% solution. It's good, but not as good IMHO as recurving the dizzy.

YOu don't need vacuum advance to allow the car to run well, just two ways to correct after you get rid of it.

Steve, I think we are just going to have to agree to disagree on this topic. Besides, we are basically saying the same thing. YOu have to readjust something to make up for loss of vacuum advance. Your method is to advance the intial timing, my method is recurve the dizzy. both will work, it's just a matter of opinion on which is best. Unless someone is willing to dyno the difference, we'll never know (though I suspect there is NOT a measureable difference either way other then maybe gas mileage).

Anyways...see what you started Scott?

There is no shortage of opinions on this forum.

Slade

 

[Lazy JW]

Well stated, Slade, you and Steve are saying basically the same things, just using different ways to describe them. I, personally, would never disable the vacuum advance on a daily driver. I still want all of the fuel economy that I can get. On a pure race car it is just extra baggage. And there are still some breaker points controlled ignitions that will make as much power as the new-fangled breakerless systems. That's my opinion, and I'm stickin to it.
Joe

 

[CobraSix]

Joe,

I am still running vacuum advance for the same reason. I drive my mustang 100 miles everyday. I want as low an initial advance as possible and get as much fuel economy as I can get. Currently I'm getting around 26 MPG with my set up.

Slade

 

[addo]

Batting for the vacuum advance:

This is cribbed from a mate's ramblings. He knows what he's on about and has built successful (on the track) quick sixes, both NA and turbo.

There's an en passant explanation of the spark control valve type setup, too.

•Vac advance is on engines generally for one reason and one reason alone - economy. At part throttle there is less a/f in there so it's not as highy compressed as a cylinder full would be at the same rpm. This means the engine can tolerate and delivers more at part throttle with more advance than would be right for full throttle at that rpm....whilst it's not worth any power at all, I'd still suggest keeping the vac advance in there.

Fuel economy is a good thing - might as well make the most of things. there is another reason. Remember the bit about transient response - where it's not producing more power on a steady state dyno, but picks up rpm better against a fixed load, and how this is important and can potentially provide better acceleration than a setup that provides the better steady state fixed rpm bhp. Well the vac advance comes in at part throttle. Depending on setup they are either routed the the manifold - where whenever there is inlet manifold vacuum the vac advance will be in effect. Others are 'ported' that's where the vac line is hooked to a port on the carburettor that is above the throttle plate slightly. At idle the orifice is above the throttle plates, so at idle it gets no vacuum at all.


As you open the throttle partially, the throttle plate lifts on that side and the orifice is now situated a little bit below the throttle plate - so then it sees vacuum. I'm not sure what all the reasons for such a setup are, but possibly there is an emissions related factor. At higher ignition advance NOx emissions go up. in the UK the EPA testing is mostly concerned with CO2 percentage at idle, but quite possibly there are other standards in effect in Aus built/sold cars...

•Personally I would - given a choice - run the vac line to the inlet manifold. The reason? this extra part throttle advance will drop away when you nail the throttle, but that split second where it lingers - the extra advance will actually allow the engine to pick up rpms a little bit quicker - so it will have a sharper throttle response. This will benefit a street driven car massively, a circuit racer enough that I'd run it for sure - even if it was worth 1/10th of a second per lap, it's got no downside or risk.

 

[Anonymous]

so your saying i should set the gaps at .40 or what? i didnt think it was all gonna go down like this. i mean i appreciate the knowledge but i'm still not sure where to set the gaps... whats goin on here fellas? thank you all for the help

p.s. anyone out there in inliner land know where to find colored hoses and wires. blue specifically?
Thanks guys


Scott

 

[CobraSix]

Scott.

For your set up...I'd recommend .040-.045. THat's what I ran with the same set up when I had it.

As far as color hoses and wires? I don't know of any colored hoses, but I have seen the stainless steel braid hose colors. You can get those from any Autozone/Pep Boys type place. You can get colored wire holders as well. As far as colored wires, the same places may have some higher performance wires that are different colors, just check to make sure they will fit. Sometimes V8 wires will fit without having to trim.

I had to custom cut mine because no local store had fitted with the ends I needed for the DS2 set up.

Good luck.
Slade