Trim to install HEI

I am starting to look at distributors for my SBB 350 build and was wondering why so many HEI reviews around the interweb for SBB’s gripe about having to trim/grind material off intake (and in one case, the head(!?).

Anyone know the likelihood of me having to do that with TA’s HEI? I assume since they say nothing of that in the description on their webpage it is not any issue, but the curiosity remains. Are other make SBB HEI’s bigger?
TIA

 

Most use a pan head allen bolt on the intake closest to the distributor. Don't know about the 350, but it is tight on the 300 and very tight on the 215!

 

What the side is with the GM HEI is one of the distributor cap clamp screws bumps/ hits the intake making timing adjustments frustrating IF you have to rotate the distributor enough.

 

I used one for many years and never had to trim anything. The only thing that was in the way was the rad hose out of engine. The new hose i have on there now gives more room for an HEI but I do not use that now. I think the GS air cleaner may interfere with the HEI but can't remember now as it has been too long since I have used HEI.

 

What do you use now and why do you prefer it?

 

What matters is the relation of the rotor to the cap. If something on the HEI housing is hitting you can pull the distributor out and rotate the housing, move the wires so the rotor to wires is the same. The rotor must point to the number 1 plug wire which has to match the compression stroke of the number 1 cylinder. Some people will not do that and instead grind material off the engine. By rotating the housing you can find the sweet spot where nothing is hitting!

 

Makes sense that differences in clocking the distributor is why some guys have problems and others don’t.

Thanks everyone.

 

I use the MSD 8548 distributor, it has no vac advance. Get the distributor on #1 with the rotor and make sure damper is at 0 on the pointer then loosen distributor and move it to the position that best does your needs then move the wires to the new positions. you have to move to the next post on cap to make this work.

 

Thanks

 

Dads regal has gm one from the factory. Im confused on what is different on his 77 vs any other? Or is it the ta vs gm one?

 

TA vs GM

 

This is a GM HEI in a 1968 350 in a LeSabre. The hose is tight. I had to loosen it and angle it a bit.

 

Yeah I brought it up because I know they were OEM in later 350’s, but so many people gripe about it in online reviews, I had to ask. As mentioned above, it seems the biggest factor is how you clock the distributor.

 

dads regal has it stock. They may have moved or modded the water neck in those years. You should be able to see it in that video. I dont have any pictures.

 

Yeah there is a way to clock them same with 455s. otherwise the advance is against the coolant hoses.

 

https://www.youtube.com/shorts/uS6we_AdO-0

you can see it real good in this short on my channel. I aint going to be hurt at you if you subscribe too lol.

 

The interference on most engines is very minor and typically it is the aftermarket 4 barrel intakes that have the most interference from the distributor. It is only a problem if you need to rotate the distributor through a wide range to get the timing where you would like it. On this Buick 350 we put together I had to grind a little spot on the aftermarket 4 barrel intake about 1" long and about 1/8' deep on the deep side to clear the distributor through the full rotation. I have circled the spot. I had just painted the engine and had to touch this spot up with a brush. No need to fear installing a HEI distributor over some minor clearancing. You can either work in a tighter range of adjustment or you can do a tiny little bit of clearancing to make it work.
Greg

 

Good info and nice work. Thanks!

 

I use the MSD 8548 no vac advance like Fox. Before that I ran a small Mallory dual point which are old school now.

I run the MSD because I don't like big, honky looking distributors.

 

This NAPA hose may help with a HEI