Hi all,

Trying to get the new ute running smooth, she's been sitting around a lot for the last few years and has corroded components on the engine which need to be cleaned up or replaced, like the temp sender - the wiring has fallen out of it it's so badly corroded!

I also have a bad miss, looking at the ignition it's all a bit sad. I intend to throw on plugs, leads, coil, rotor and cap but the dizzy is where I'm not sure. It's an 81 build 351 clevo with electronic ignition and I'm certain the dizzy is original and has never been touched.

The ute runs a dual fuel (petrol/LPG gas) (gasoline/propane for the Americans) setup, but in the future I intend to make it straight gas - LPG only.

So - is this dizzy worth keeping, can they be rebuilt and can they supply a decent spark for LPG teamed up with a good coil?

Or - what setups provide good fat sparks for these engines nowadays, I've seen the Procomp complete setups that are reasonably priced, assume they are an MSD copy ( can't afford genuine MSD), are the Procomp components any good?

Any & all comments and advice welcome - I haven't touched a car with a dizzy or leads in 20 years!

Cheers Brad.

 

Brad,
In the early 70s the US had a fuel shortage and I converted several gasoline engines to dual fuel; LP/gas. There were several changes that needed to be made but we kept the original dizzys. Some of the dizzys even had points!! I believe any good dizzy/coil combination will provide enough spark for your LP engine. My 2 cents worth.

 

Get tune up good to go. Then look at ignition issues like proper voltage to distributor 12 volts, need to confirm. also since been setting for awhile look at your engine grounds and related issues from battery and grounds to frame! good rotor/cap and vented cap! make sure distributor doesn't have to much play in shaft from worn bushings. simple stuff thats not so simple sometimes. good luck and chat soon.

 

Good tips there, thanks guys. Now I've just gotta make room in the shed and get working on this baby.

 

Just the main thing I can think of, is re-gapping the spark plugs for LPG/Propane.

 

Thanks Adrian, I've read a bit on using the iridium plugs and gapping them down .1 to a .8mm gap so I'll do that.

 

Well, let me start by saying I agree that it's just time for a tune-up....
then let me speak on the topic of ignition points & the aftermarket "kits".....

You will have to excuse me a little here, but, what is more reliable than points......certainly not the more popular & common “e-box replacement kits”. Yes you can hear people state "It runs so much smoother/better than when it had points"........in each case that an individual said that in my presence, they had very little knowledge about points and the ones they were running were- old & tired or inexpensive aftermarket replacement units or the individual (including professional mechanic) was unfamiliar with not just setting the gap to OEM specs, but setting the dwell & initial timing to what the engine likes.

But let’s look at the OEM ignition system from the early 60’s….
Original Coil Voltage: 20,000; by the end of the 60’s 40,000 volt high performance coils were common…..by the 70’s 50,000 & 60,000 volt coils were easily available & is what we have today. Did we really gain all sorts of HP/TQ with all this extra voltage…….no, what we were able to gain was stronger support (if you will excuse my terms here) for higher RPM’s- specifically in the 6,000+ range…..enough to power NASCAR engines in the 8,000 rpm range at 200+ mph!

Points were used in NASCAR up through the late 1970's, running speeds of 200mph+.........Cale Yarborough did lose a race one time because the ignition points broke. In a street application, if you look at the data very closely that is provided by these more common e-box companies, in street applications (where max power-band RPM is around 6000), when the standard dyno deviation is removed (5% standard per every dyno mfg) there is less than 1% improvement in performance. Further testing by independent aftermarket DIS (direct ignition system) manufacturers verify this through their own testing- there is little gain over an ignition points system until you reach 4000 rpm…then you begin to see a slight sustainment of ignition delivery above what points can deliver but it doesn’t even begin to compare to what a “modern”, real e-based system can & does deliver in a real world street (and race) environment.
I am not promoting this product but their analysis is very demonstrative of actual performance results. link: http://www.compu-tronix.com/MightyMo...risonGraph.pdf
The other item is, in a street vehicle, if you wait to see improvement until 4000+ rpm, the race is over.
Here is a link to a back to back ¼ runs- comparison of points vs a couple of e-box conversions……..no discernible difference PerTronix Track Test

These e-box “conversion kits” have literally the same design limitations as the “conventional points”- because they are essentially using the same delivery system (rotor, cap, wires, etc.) and they are subject to the same inherent design impactors of which there are numerous….including ozone that is produced within the cap…..none of this has by miracle “disappeared” and in fact when compared in true recorded data-frame analysis, the benefit will be gone by 5800 rpm and the loss, although slightly less, parallels that of points. In racing conditions that could very well make a difference, but in a street application, you could literally change brand of fuel and see that level of improvement or degradation. Additionally, there are companies such as ProComp whose “High-Tech Multiple Discharge Ignition Systems” are nothing more than re-boxed low tech conversion parts purchased in bulk from other companies- mostly Chinese-based. Check out this pic procomp ignition box?? of a “new” ProComp e-ignition system- it’s a glued together GM part stuffed into a pretty aluminum box. Considering they were sued in 2006 by MSD (and prohibited as part of a settlement from using/distributing any of their parts), I’m not surprised by anything I see with their crap….but this includes much of the e-box aftermarket industry- a lot of PR documents which physics does not play any part!

Very good quality ignition points/condensors are available and when set properly, are very reliable and provide excellent performance. There have been no less than 5 people who I personally knew were going to get e-boxes, then I had them get a good set of points/condenser, a high voltage (40k+) coil, and installed them showing them specifically how to do it......the engines ran smooth and strong. One person did end up buying an e-box, why, because he said he just got tired of not being "cool", after spending $500 for a distributor, etc (he went “Popular” high end), a year later (when he asked me to help him fix something) he admitted, it was a waste of $...it didn't run any better than after we put the points in.

While many state the positives of e-boxes (and there are certainly many positive attributes), there are conditions which reduce an e-boxes effectiveness & reliability....to start with the circuitry and handling (container vessel shipping) of it from China (which is where 90% of the more common/popular e-box company's products originate). Any aspect including temperature control, static safeguards, moisture can & will cause both detectable and undetectable damage which may not show up until after you have subjected the installed component to real world vibrations, heat, cold, moisture & grease/oil. Yes, all of these damage e-components, but the systems (based upon a variety of factors) are suppose to be prepared to endure these exposures but that is based upon many, many assumptions. Including proper handling & q/a.......given all of the 3rd party involvement in the final product, it is unrealistic (IMHO) to believe that e-boxes have an increased reliability as compared to their mechanical-based counterpart. And in terms of “Dwell Control” I won’t even go into that in detail but I will say, what the “kits” provide is a joke…..you can actually get more control over the dwell by having an understanding of how to set timing versus dwell setting with points than the most popular e-box conversion kits can provide…..which makes for a very smooth running engine- this is not just IMHO, but well known among the "higher quality" aftermarket engineers whose systems reflect this ability to "tune"!
If you need to say I got rid of my points…ok, that’s fine, but if you are really serious about actually upgrading the ignition system then do so……although it has been scrapped by the OEM’s in favor of more advanced, effective systems, there are aftermarket DIS units (yes the same as Ford used in the 90’s & developed by Porsche in the 80’s) whose cost is within reach of most buyers and will actually perform as stated.

 

Wow, great write up Beechie,
That's exactly what I needed to read, especially the procomp data and pics.

I have a factory electronic dizzy, so no points, but now I'm definetly going to stick with the factory dizzy.

I'm scared to rev this ute to 6 grand, it's not built to go that fast!

 

IMHO great, smart choice....the oem's (including Porsche) spent a lot of $'s developing those and they really perform well!!!!!!!!!!!

 

Well, to play Devil's advocate here that statement applies to 90% off all the electronic devices and components in America. TVs, cell phones, computers, telecom gear, avionics, whatever. I know Made in China is supposed to be universally bad, but where something is assembled doesn't matter if the supply chain and QC are properly managed.

Which is why an MSD branded product made in China doesn't concern me. They have a very significant interest in maintaining their reputation. They're not going to allow Flextronics or whoever assembles their boxes to send back products that don't meet the same quality standards as their domestically made boxes.

If it's a worry to you then get a made-in-the-USA 6AL box. Which would still have to be shipped down under, though.

The multiple spark at low rpm from a cd box is nice but the Duraspark II works very well.

You might also check out the DUI Duraspark distributors, Summit Racing sells them. They blueprint them out and recurve for your engine. The one I got is very nice, very precise advance.

 

Thanks Baron,

Yes Summit have some great stuff, you guys can go nuts with free delivery etc. unfortunately for us we still pay through the nose for freight. But it does give us more options to get parts.

Cheers Brad.