1968 250 6 cyl HEI conversion

[jaw0001]

I have a 1968 250 inline 6 with the big factory A/C compressor. The compressor sits just 2 inches above the top of the stock points-style distributor cap. Has anyone tried to install a large cap HEI in this application? I'm worried the coil-on-cap will hit the bottom of the compressor. There also only seems to be about a 1/2" or so between the stock points distro cap and the side-of-block. There is no reason why the HEI body wouldn't fit at all in there is there? Actually the engine and compressor are from a 1968 Buick Skylark but I figure it would be the same.

Thanks all.

[ray_mcavoy]

Welcome!

You might want to look into getting an early inline-6 HEI.

Unlike the V8 HEI's (which started out with the coil-in-cap setup), the early 6-cyl ones (from around 1975, 76, and into 77 I think) had an external coil and therefore a lower profile cap.

Here's an example pic I found using a Google search ... one on the left is a 75 inline-6 external coil HEI and the one on the right is a V8 coil-in-cap HEI.


The external coil used with the early inline-6 HEI looks looks like this.


And if you can't find an early inline-6 HEI that's already set up for the external coil, I believe a later one can be converted by simply swapping to the early style cap & rotor and changing the wiring harness that connects the module to the coil.

[VetteVet]

Try some of these.

http://www.google.com/custom?domains...D%3A1%3B&hl=en

[jaw0001]

It does seem to shave off a little height to run the external coil, but how much? Upon seeing some HEI 250's on youtube there is no freaking way a normal coil-on-cap HEI will fit under the A/C compressor. When I bought the car it was so novel that the A/C works. But it's kind of a PiTA because it limits working on the engine, because AC is so expensive to work on anymore. One doesn't just willy-nilly blow off the system and purge and refill with R12 when you're done tinkering with something else.

[_Ogre]

the addition of the hei distributor to that motor will impress you as far as easy starting and idle
it would be well worth it just to modify the ac compressor bracket to raise the compressor
no need to discharge the r12 to mod the bracket

an alternative is to use pertronix points eliminator, not quite hei, but a better alternative than points

[jaw0001]

Langdon sTovebolt said no hei, including coil-on-cap, external coil, and his mini hei, will fit a 1968 with factory ac. So looks like pertronix for me.