The Stovebolt Site Forums The Shop Area The Electrical Bay Pertronix Question

I have really gone around in circles on this one. I am currently running a 1955 235 with a 1953 distributor converted to 12 volt negative ground. From a previous thread I figured I needed a 1157P12 unit. When it showed up it said positive ground on the box so I knew that wasn’t going to work. Turns out 1157 is for the older distributor with a 12 volt conversion. 1157N6 is what’s required for those not converted. 1158 is supposed to be for 1955-1962 12 volt distributors. I returned the positive ground unit to Pertronix and they said they would exchange it for a negative ground one. It arrived in the mail and it’s the exact same one as I returned so now I have to do it again. Does anyone know the difference between the 1157 and 1158 as in the future I will be dropping in a 1956 261 and would like to use the same unit. Hopefully it’s just a small difference in the mounting plate that I can modify. Since I have to return it again I am wondering if I should just get the 1158. Anybody familiar with this?

Thanks,

Curt B.

Curt,

Are they 1157 & 1158, or 1167 & 1168?

There is good information on the Pertronix site - they have a catalog that can be downloaded. However, they do list 261s in earlier years and 216 in later years.

Here is the Pertinent Page (PDF).

Here is a JPEG of the pertinent page

The 1953 and earlier distributors need a specific style/size unit and the 1954 and later distributors use a different style/size unit. The footnote explains how to specify positive or negative ground and 6v or 12v.

Will you be using the 1953 distributor (1167 Pertronix unit) or the 1956 distributor in the 261 (1168 Pertronix unit)?

To complicate the answer to your question, I think that some people have posted that 1953 was a transition year for the distributor. If you have both distributors, see if you can discern any differences.

Tim

Tim,
Thanks for the reply. I was going by memory when typing (which seems to be slipping away) and was referring to 1167 and 1168(duh). Really what I what to do is put it on the older distributor currently in my truck and when my 261 is built just tranfer it to the newer one.
I considered using the 261 distributor now but it is a low mileage unit and prefer to keep the cam/distributor relationship undisturbed. A local rodder guy is telling me they all do the same thing so just butcher the plate if required. I guess I could pull the 261 distributor and compare them side by side.

Curt B.

Curt,

Ignore the hot-rod guy unless he really knows 216/235/261 engines.

At some points in time the distributors changed. Some of the changes had to do with how the points were attached. the height of the rotor and cap, and the cam drive gear (also the angle of the vacuum unit but that is not really a change in the distributor).

Unless someone can post here what changes might be important to you, you might want to wait on buying/installing the Pertronix unit until you install the 261 - get a 12v 261 unit for a 12v 261 distributor of a known year.

Good luck,
Tim

if your truck isn't stock a later 250 chevy HEI will drop in with minimun mods. the only difference is tou have to remove the stock flange on the HEI so it drops down to engage the oil pump. i built one for my 54' burb and it works great. under $50 bucks