I've searched and searched and can't find my answer.

How do I convert from my current '90 charging system to an older, external regulator, style system? I'm having problems lining up the small block alt. Thought it might be easier to convert?

Thanks!

 

More details! Got more info/pics on the swap or is it in the planning stage? It may be easier to get an older alternator other wise you will have to mod the brackatry.

 

Here's the build thread:
https://dodgeforum.com/forum/1st-gen...ld-thread.html

I have the 383 on an engine stand. I'm trying to figure everything out before I install the motor. I'm thinking it may be easier to modify the original small block alt. bracket instead of going to an external regulated alt. ??????

Or, is there a way to modify the '90 alt. wiring to accept an older alt.????

 

Well, I might have answered my own question.
It looks like a '90 alt with an internal fan will mount up to the big block
brackets.
Off to the parts store.

 

Just a few things i noticed/wondering about. Did you have hardened valve seats put in the 906 heads? Not sure if the alternator had a regulator or did it have a pcm do it in 90. Looks like it would be best to use an external one since the pcm(if any) is not being used. Wonder if the fuel pump will put out enough to feed a big block? You may need to upgrade the radiator also. Nice work so far on the truck!

 

Yep, 906's are in the shop being treated to new hardened seats, new guides, 3 angle grind, bowl and port work.
Using the PCM is where I'm stuck. If I go with an external (old style) regulator, I'll loose my volt gauge.
I'll find out about the fuel pump and radiator. The stock rad is a 2 core. I have a new 3 core bookmarked. Might be able to get away with the 2 core and an electric 'pusher' fan?

Thanks for the compliment!

 

I had built a motor with 906 heads (non hardened seats) back in the 80's just before leaded gas was no longer available. The car was a daily driver until i pulled the motor. When i pulled the head off i was shocked to see the exhaust valve at least a 1/8 inch in the head! Hardened seats are a must! I'm not sure how much the pcm does on a 1990. It could be eliminated with some work. A mechanical gauge dash would be nice.

 

Hardened seats or not hardened seats, that is the question. LOL
I called 4 machinists, 2 said yes, 2 said no. Figured I'd go ahead and do it.

I've been searching the 'net for months about what to do with the alt. None of the articles even mention it. "Just a bolt in" everyone says. I think I had the wrong style alt (external fan blades).

I hate to loose the factory gauge as I have custom white gauge faces in the dash. Attached is a pic of my daily driver '90.

Hoping to have the truck running in the next few weeks.

Thanks for the input!

 

I don't know who told you no to hardened seats but he wouldn't be doing any work for me! The alternators shape has changed but it works the same. Whatever you put on it just use the pcm to regulate it. I'll have to keep an eye on the build thread.

 

Well, I found out my small block water pump pulley and crank pulley won't work.