Distributor Recommendations

[Pat014]

Hey All,

Please forgive if anything I'm writing seems silly, I'm learning as I go here and have very little experience with distributors.

I'm currently in the process of replacing some worn items on an 85 K10; one of the items I am looking to replace is the distributor.  The truck will be used solely as a daily driver and some occasional towing. From what I've gathered the motor installed is an '89 350TBI w/flat tappet cams, the ESC has been removed, the distributor is a Delco-Remy HEI and has vacuum advance.

I have searched through the forum and have a couple ideas, but I'm looking for recommendations on a good quality distributor that I can rely on. After reading some recent customer reviews of some of the more expensive brands I'm a bit hesitant of all of them; not sure how bad Covid screwed everything up.

Regarding fitment, the various sites I've looked at have numerous years/engines listed for compatibility. I have no clue what the motor was originally out of or if that really matters. I would assume selecting a distributor for an '89 Chevy Surburban with a 350 would be fine, correct? Or, should I just be entering an '85 into the search criteria? I know I will obviously have to measure the old distributor height.

In searching I see the following options available:

-Blueprinted units - A quick search says this is probably what I'm looking for. Anything specific I need to know about these units?
-Different types of gears available; can anybody tell me what would be the ideal choice as stock replacement? I'm assuming the cams are stock.
-Adjustable vacuum advance; is there a certain range I should be looking for?
-Some kits have ignition boxes and an external coil is there any benefit there?

I am well aware I can go to the local auto parts store and pick up a replacement, but I honestly have no faith in their quality.  Is there any reason to go with a performance brand(MSD,Holley etc) if the motor is not going to see significant performance upgrades? I am ok with spending up to $350-$400 if it helps buy me reliability.

If you made it this far, thanks for reading.

[JohnnyPopper]

Welcome!

SBC engines haven't changed with regard to the distributor "dizzy" from early on till they went totally electronic.

HEI dizzy's are the same from 73 to 87? So form factor, gearing, height etc should not be an issue.

Someone will flame me if I'm wrong...

So fitment shouldn't be an issue if you're in that year range.

I don't know that much about the advantages of aftermarket dizzy' other than people swear by them for their own reasons.

Full disclosure: I jumped on this thread with my limited knowledge, hoping to glean some gems of truth regarding them.

[VileZambonie]

HEI dizzy's are the same from 73 to 87? So form factor, gearing, height etc should not be an issue.

Someone will flame me if I'm wrong...

I would flame you for saying dizzy's

TBI engine, but not TBI, correct? HEI vacuum advance with a carburetor I assume?

[werewolfx13]

As someone who has worked in the auto parts business for years, if you stay away from MSD/Accel, most parts store house brand GM HEI distributors are fine.

[Pat014]

Johnny - I guess my main concern is that there seems to be so many options for SBCs distributors it can be daunting trudging through the specs.

Vile- The engine, based on the block stampings, shows it as a TBI engine from 89. Now however, it has a traditional carb, not throttle body injection. There is a vacuum chamber attached to the distributor that was connected to the carb; not sure of its operability as I haven’t had the motor running due to an intake manifold leak. I can try and post a picture of it before I tore it down.

Werewolf - I’m taking that as I shouldn’t look at MSD/Accel? Obviously there’s name recognition there but some of their reviews  were off putting, especially given the price.

[VileZambonie]

If it's a stock TBI engine with a carburetor it's not going to be a powerhouse so a stock HEI is fine. If you buy locally you have the advantage of getting a replacement warranty unit lickety-split as opposed to an online purchase.

[Pat014]

Any reason I should be looking at a melonzied gear or is iron fine? Seems like all the standard units have iron gears. The local options seem to be pretty limited with a subpar warranty, one was only 30 days; these are at least 12 months.

These are the two I've been looking at.
https://www.summitracing.com/parts/acc-59130/make/chevrolet#overview
https://www.summitracing.com/parts/MSD-83623

What's the typical thing to go out on one of these units? I've read the coil but anything else internally that ends up going bad?

[Rapid Roy]

I got one from them in 2018 and it lasted about a year. I don't remember the exact one. Replaced with Accel. Lasted 1 week. Finally got AC Delco ignition module and pick up coil in 2019 and has been working great since then. My thoughts are AC Delco parts are the better choice, at least for me.

[VileZambonie]

84-1845 = 24 month warranty

[Shifty]

Whatever you get nowadays will have a chinese module and pick-up coil, keep that in mind if it bothers you.

[JohnnyPopper]

Since you have a HEI, why not have a shop check it out for wear and mechanical advance?

There is a speed shop nearby that charges a buck fifty to go through it. Let me know if you want their contact info.

You must have a dyno shop in your neck of the woods, no?

And yes, the trove of options makes me dizzy too.

[philo_beddoe]

Yeah, ya can’t beat a good ole AC Delco, hand built at the factory in Detroit, MI.

[Stewart G Griffin]

Any reason I should be looking at a melonzied gear or is iron fine? Seems like all the standard units have iron gears. The local options seem to be pretty limited with a subpar warranty, one was only 30 days; these are at least 12 months.

These are the two I've been looking at.
https://www.summitracing.com/parts/acc-59130/make/chevrolet#overview
https://www.summitracing.com/parts/MSD-83623

What's the typical thing to go out on one of these units? I've read the coil but anything else internally that ends up going bad?

Make ABSOULTELY sure you have a flat lifter cam.  If that's the case, iron is fine.  If it's a roller cam, then you have to go melonized.    i'm thinking 89 tbi engine should be roller, but not 100% sure?

i'm not an engine person, but my feeling is stock gm hei is fine.  i also think ProForm is a good brand.

[Stewart G Griffin]

Hmmmm......i'm reading that truck engine DID NOT get the roller cams until about 96-ish?   But car engines DID get rollers starting in 87.

This is a little confusing as the 4.3 v-6 DID get rollers in cars AND trucks beginning in 87.   But the v-8's in trucks DID NOT (apparently) come with roller cams until 96ish.

So, bottom line:  Stock Flat lifter cam + iron distributor gear OK.