best option for distributor upgrade on 250-6

[psychobilly451]

I want to upgrade my distributor. should I get an hei? or pentronics? and what else needs to be replaced? plugs, wires, coil?

[71meangreenc10]

I put HEI in mine, but i had to wire up the coil from scratch, but it worked, you should regap the plugs to get the best spark from HEI if they are ok, plug wires must be changed unless you can get a kit to change the ends to fit HEI caps.

If you dont want to do all that Petronixs is fine, I have used it and it worked. Just easier to get HEI parts if something goes wrong...

Smitty

[bubba327]

Absolutely get a HEI of some style. I have always used a stock GM with never a problem. I grabbed the the last one from a 77 Nova with a 250 I-6 in the junkyard .
Some guys have gotten the E-bay specials but they report some extreme play in the tolerances on occasions especially on the imported stuff.
My local pick a part yard always has at least one usually found in a old farm truck or 4-door nova with a I-6. Grab the plug wires while you are there.
Remember to remove the resistor wiring found in the old wiring harness for the points set-up

[geezer#99]

Definitely an HEI. Pertronix if you want a stock look. With the Pertronix you're putting new parts in an old worn out distributor. I had both. Hei cured some missfires I had with the pertronix. You'll need new wires with an hei though.

[psychobilly451]

hei it is.

[bubba327]

It does not hurt to check them out if it does come from the junkyard, I have never found one that needed shimming to get back in specs. I have bought 4 now and never had a problem with any one.
Most yards have a return policy- grab two and use the best one, return the other.
You timing will need changed. Your 250 should like about 8*-12* and 32*-36* total advance where you are probably 2*- 4* now

[psychobilly451]

thanks for the heads up for timing.

[raycow]

I agree with all of the above. Pertronix if you want the stock look and factory HEI for cheap and easy parts availability. One advantage of the Pertronix not mentioned above is that if you carry the stock points and condenser in your glove box, you can re-install them in a hurry if it dies while you are out on the road. You can't do that with an HEI.

Ray

[chevy88]

Originally Posted by bubba327

Absolutely get a HEI of some style. I have always used a stock GM with never a problem. I grabbed the the last one from a 77 Nova with a 250 I-6 in the junkyard .
Some guys have gotten the E-bay specials but they report some extreme play in the tolerances on occasions especially on the imported stuff.
My local pick a part yard always has at least one usually found in a old farm truck or 4-door nova with a I-6. Grab the plug wires while you are there.
Remember to remove the resistor wiring found in the old wiring harness for the points set-up

What happens when you forget to remove the resistor?

[El Jay]

HEI need the full 12VDC to work properly.

[chevy88]

My truck seems to power out around 60mph hopefully that is the problem.

[bubba327]

The wiring for the old points distributor has a resister wire in the harness from the key to the old starter relay post then on to the coil/distributor. (I do not remember the color Maybe pink???, check the wiring diagram here in the FAQ) I think purple is the starter engage wire.
This drops the voltage from the key to the coil to a lower voltage (approx 9 VDC) which extended the life of the points,The (Yellow?) wire from the starter delivered a full 12+ to the coil only while the starter is engaged. There are two sources of power while the starter is engaged.First from the "key on" the resistor wire and second through the starter relay contacts from the positive battery cable.
The HEI wants a constant 12 VDC from the key thus the resistor wire needs replaced with a normal conductor and the starter " voltage booster" wire needs removed and eliminated.