I am sorry about hijack, but this plays in well with this discussion, I think. Fakesnake brings up a good point. Under what application do you need an iron gear, steel gear, or bronze gear on the dizzy? What is included with the stock dizzys and why would you need something else?

What I used on my 351W stroker was MSD8578. It is quite as large as the normal dizzys but it is mechanical advance only, which I preferred.

As for why go MSD, because it will fire when other ignitions will not. I was having bad plug fowling issues when first starting the turning process (dead rich), but I never had a cylinder firing issue, mostly because of MSD's multiple sparks I think.

 

iron gear for a flat tappet cam
steel gear for a roller cam
bronze i *think* will work with both - but i cant recall for sure

also, and most people just dont know this.... crane makes a much nicer ignition box IMO than msd does, i would seriously consider using their stuff. i have an msd 6al and blaster 2 coil, but if i had to buy it again i'd be going crane.

 

I tend to not like generalizing what needs to be used when. I called MSD regarding the gear and they couldn't say which to use and recommended I call the Comp Cams and ask them. OK.. so I call Comp Cams and wait 20 minutes on hold for a 60 second question. The tech stated that their cams are designed for the stock gear. WTF? Stock could be iron, steel or bronze. I asked about the generalization (iron = flat tappet ; steel = roller) and he said no and went on to explain. Basically he said it comes down to what water pump your using. If its a stock pump use an Iron gear and if its a high flow pump use a Steel gear.

So again.. its back to generalizing.

urban_cowboy.. no worries on the hijack. I have no problems with people asking questions related to the thread. Wish it worked a bit more like that here actually. Thanks for your suggestion on the 8578 distributor. I noticed its an Iron gear.. what pump are you using.. lol. Do you have an oval air filter? The wife wants an oval filter though at this point she'll get what will fit.

MSD has a long time proven track record regarding ignitions and their reliability. I want something that I feel 99.9% comfortable with. Don't think I've ever even seen a Crane ignition box in a car. Not saying they aren't good just haven't heard of them before.

 

Let's try to clear this up a bit. There are actually four types of cam gears:

1. Iron: Required for iron core cams, most common for older cars with flat tappet cams.
2. Steel: Required for steel core cams, most common for newer engines with roll cams.
3. Bronze: Can be used with either, but is "sacrificial" in that it wears relatively quickly, particularly with a steel roller cam. Debrise is not significantly harmful to the engine, but is typically used in race applications with frequent engine rebuilds.
4. Composite: Relatively new product from Comp cams, can be used with either flat or roller cams.

A flat tappet cam (both hydraulic and mechanical) use an iron core for the cam and require an iron gear on the distributor. A roller cam (both hydraulic and mechanical) use a steel billet core for the cam and require a steel gear on the distributor to be totally compatible (stock set up for roller Ford engines).

Now, unfortunately, we can make this confusing. Some cam manufacturers press an iron gear on their steel billet core roller cams to make them compatible for retrofits. BTW, that wp comment from the tech guy is pure bs. I can only assume he means that if you use a reverse rotation wp on a Ford, there is a good chance it is a steel cam and requires a steel gear, but that is really lame thinking.

So to cut through all this crap, post the part number for your cam and I'll tell you what gear and MSD distributor to get.

 

http://www.cranecams.com/index.php?s...&lvl=4&prt=127

they make em in a small or large cap.

http://www.cranecams.com/?show=brows...mber=6000-6400

better than the 6AL, no extra "chips" needed to be bought to set your rev limit

http://www.cranecams.com/?show=brows...umber=730-0092

coil

and there ya go

 

Mark, the Cam was listed above.. and is CL35-424-8. Specs are linked at the bottom of that page. Thanks for your suggestions as I do value your advice. The tech didn't say anything about a reverse rotation pump.. just standard flow vs high flow. I though it sounded odd myself however I'm completely new to this so who am I to disagree with the tech who 'should' know more than I?

MSD suggested 85840 (steel) or 8584 (iron). I like the shorter 8578 (iron) that urban_cowboy is using because it might allow an oval air cleaner though not a priority. The iron gear can be changed to steel if needed using 85834 which requires drilling, correct installation and more money of course. How can a smallish gear like this cost so much!

my77stang.. Thanks for the suggestions and the links. I might have to look into their stuff a bit more. Note that the new 6AL-2 MSD boxes don't require the chips any longer either.

 

yeah and i believe they dont "pop" off the rev limiter like the 6AL's do.

that crane dizzy has "vacuum" curves programed into it, and has a bunch of different advance curves so you can just dial it in without having to mess with weights and springs (if i remember correctly). it really is an excellent piece of automotive hardware.

 

I run a 6 AL on the track car and so far it runs great. Also a MSD distributor with a mechanical advance. If you plan on running boost in the future, then you may want to look at the 6AL2. Here is a good article on distributor gears.
http://www.carcraft.com/techarticles...ars/index.html

 

I am still putting together the pieces but so far for my 351c 8477 distributor with the 6AL2 and Blaster coil, I went with the 6AL2 for the smaller size and rev limiter installed instead of buying rev chips, also has low and high limiters.

I dont know the cam as I bought the engine assembled without specs on the cam so hopefully the distributor supplied (8477) is the correct one.

One question as I have not installed this, what do you guys do with the wires that are not used on the control box? Any tips on where to place the box? 72 Mustang.

Thanks

 

So what happens if you run a iron gear on a steel cam?

Adrenolin, I am running a round K&N filter, but It looks like an oval cleaner would clear over the top of the dizzy...of course that would depend mostly on how high your intake is. I am running an Air Gap, so my cleaner is way up there.