351 Distributor

Ant · #1 (**permalink**) 09-11-2011, 01:29 AM

I am after information on Ford 302/351 distributors regarding height differences.
Is it possible to get a lower 302 distributor and change the gear to suit my 351 camshaft?

Rick Parker · #2 (**permalink**) 09-11-2011, 03:52 AM

The Fly in the ointment (we say that up here

) may be the diameter of the shaft vs guide hole in the block etc?? But you can always machine the hole in the gear larger or possibly make a sleeve for the shaft?
Or better yet, remove a section of the 351 shaft, reweld it. Then grind or true it in a lathe and use a 302 housing and size bushing(s) accordingly.

Here are helpfull hints on actually getting the installed length correct.

http://www.fordracingparts.com/downl...tM-12390-A.pdf

mreid · #3 (**permalink**) 09-11-2011, 06:15 AM

The bigger issue is the oil pump drive shaft. It is 5/16" in a 351w, but only 1/4" in a 302.

wolf k · #4 (**permalink**) 09-11-2011, 06:36 AM

I am pretty sure the dimensions are the same on the two distributors in regards to gears and distance to clamping surface. The dimension of 4.035 is the same on 302/351 distributors and gear outside dimension is same on both. 302 gear will mesh with your cam. So your issue would be oil pump drive as stated by mreid and interference with intake manifold.

Ant · #5 (**permalink**) 09-11-2011, 09:39 AM

My engine is dry dumped so the oil pump drive not an issue. I am been looking to see if there are shorter 351 distributors as I have got this one from ICE and the lead retainer thumb-bolts are just poking through the hood, will talk to them about getting a custom distributor done 2" shorter. The MSD8578 was about 1.5" lower.

mreid · #6 (**permalink**) 09-11-2011, 01:43 PM

If you went with a crank trigger, you could lose almost three inches in height.

bobcowan · #7 (**permalink**) 09-11-2011, 06:11 PM

The only differance between the two distributers is the oil pump drive shaft. So, for, they're all the same.

I also needed a short distributer for my intake. The shortest I could find for my application was the Mallory Unilite.

I looked at the blower specific distributers, They're much shorter but their advance is limited to about 12-14*, IIRC. I'm almost willing to bet they could be modified for more advance, but I'm not sure. If the Unilite had been too tall, I would have tried that.

Ant · #8 (**permalink**) 09-12-2011, 03:24 AM

I have heard that a Cleveland distributor is 1-1/4" shorter than the windsor is identical in the important dimensions for fitting to a windsor block and all that is necessary is to fit the windsor drive gear to its 0.530" shaft.

Jac Mac · #9 (**permalink**) 09-12-2011, 12:10 PM

Just make sure you get the correct clevo dizzy for a USA block Ant, the Aussies reduced the spigot size where the shaft runs in the block by about 0.025" or so, why, I dont know, all it acheived was many ruined dizzy gears when guys replaced the late model blocks with earlier USA ones and refitted the late model distributors.

Ant · #10 (**permalink**) 09-12-2011, 04:16 PM

Quote:

Originally Posted by Jac Mac

Just make sure you get the correct clevo dizzy for a USA block Ant, the Aussies reduced the spigot size where the shaft runs in the block by about 0.025" or so, why, I dont know, all it acheived was many ruined dizzy gears when guys replaced the late model blocks with earlier USA ones and refitted the late model distributors.

Thanks for your input Jac Mac, their website lists the two sizes for Cleveland 0.530" and 0.490" I am sure he would be up to speed on my requirements but better to check out for peace of mind. ICE gives great service as they are paying for the freight on the exchange when they supplied the correct part. I also havent found a bad report on them.

Ant · #11 (**permalink**) 09-12-2011, 04:34 PM

Thanks guys for the good information.

I am not sure I really need this Ice Ignition system, as most of my use will be under 6000rpm at least is should have a nice spark when I use it around 7000rpm plus good reliability which is the main reason I purchased it. Also I am used to setting up total advance and altering springs to set the advance curve, with this setup it has a heap of programmable advance curves. This engine had all the advance in by 2500rpm which I think is too low. I am a fan of setting things and leaving them.

Ant · #12 (**permalink**) 09-28-2011, 03:28 AM

I contacted ICE and Cleveland dizzy on the way same shaft as Windsor with the correct steel gear for my flat tappet cam, he mentioned there is a chance of spark scatter due to not having an oil pump connected to the dist and backlash in the gears could become more of a problem as the oil pump acts like a damper, this may only happen in 1 out of 10 and if that happens a crank trigger would be a solution. I dynoed my engine with an MSD8578 Dist and the timing was very stable.

Better to get to work and finish the interior, build a new IRS and I have an intake system to design so heaps to do before the engine makes another noise.

mreid · #13 (**permalink**) 09-28-2011, 06:02 AM

A flat tappet cam needs an iron gear, roller gets a steel gear. Is that what you meant?

Glad to hear you got the rest of it worked out!

Mark

Ant · #14 (**permalink**) 09-28-2011, 11:07 AM

Quote:

Originally Posted by mreid

A flat tappet cam needs an iron gear, roller gets a steel gear. Is that what you meant?

Glad to hear you got the rest of it worked out!

Mark

Yes Iron gear, thanks for your comments.

Ant · #15 (**permalink**) 10-12-2011, 04:27 PM

Dizzy arrived and it has got a 0.490" spigot shaft, the gear measures ok - damn I was hoping it was the correct shaft. I spoke to supplier he said its not an issue as the housing has a bearing and bush supporting the shaft, and its less of an issue for me as I am dry sump. They supply this distributor for US windsor as well and never had a problem.

I am thinking for peace of mind I should get a sleeve made up to take up any side loading.

Rick Parker · #16 (**permalink**) 10-12-2011, 05:00 PM

The shaft MUST be supported on the end in the block under the gear. The bearings or bushings in the distributor alone are not enough to support the shaft alone.

Ant · #17 (**permalink**) 10-12-2011, 06:16 PM

Rick,

Does it still need supporting if you arent driving an oil pump?
I could get a machined sleeve it would be 0.020" thick which is getting thin, or have the shaft ground for a thicker sleeve, as there is no real load on the shaft I am wondering if the shaft would deflect at to touch the block spigot hole.