HEI or Mallory HyFire?

[64FJ40]

I'm in the middle of swapping the 350 out of my 71 K20. It was already running HEI, so keeping that setup seems like it would be easiest.

The motor that's going in already has some kind of *bling* Mallory dizzy, Promaster coil, and a separate box that controls variable advance curves or something like that? This is also a 350, but with a decked block and lots of $$ into port-matching and head polishing and balancing and whatnot.


My inclination is to keep it simple with the HEI if the power difference is negligible, but I don't want to waste potential by going cheap... I like the fact that it would still run off-the-shelf parts as well.


Which would you run and why?

 

[SemiTrkDrvr]

I'm in the middle of swapping the 350 out of my 71 K20. It was already running HEI, so keeping that setup seems like it would be easiest.

The motor that's going in already has some kind of *bling* Mallory dizzy, Promaster coil, and a separate box that controls variable advance curves or something like that? This is also a 350, but with a decked block and lots of $$ into port-matching and head polishing and balancing and whatnot.


My inclination is to keep it simple with the HEI if the power difference is negligible, but I don't want to waste potential by going cheap... I like the fact that it would still run off-the-shelf parts as well.


Which would you run and why?

If it runs fine with the HEI, I'd run that. You answered your own question. Keep it simple and repairable with off the shelf parts. Now if it was going into a hot rod, go for it.

 

[64FJ40]

If it runs fine with the HEI, I'd run that. You answered your own question. Keep it simple and repairable with off the shelf parts. Now if it was going into a hot rod, go for it.

It came from a hot rod, so I just wanted to make sure I'm not missing something by leaving it out when putting the motor into a truck. Swapping the dizzy sucks once it's installed, so I don't want to have to do it again.

 

[SemiTrkDrvr]

I never install a Chevy motor with the Dizzy installed. For several reasons but its mainly personal pref. 1) It's one of the fastest ways to break the dizzy if it happens to catch on the firewall during install. 2) I always prime the motor to build oil pressure before I fire it off for the first time after installed. And this is done where the dizzy is mounted. It really does not take long to swap the dizzy if your truck is already set up for the HEI. Again I just do it this way cause its the way I was taught and its worked for me every time with no issues.
Rgds,
Dennis