Archaea

I bought a 383 shortblock from a vendor. I need to buy a 400 externally balanced flywheel I've been told. When I called the local performance shop to get the new flywheel they had two questions.

1. How many teeth are on the flywheel?
2. Do I have a one piece rear main seal or a two piece?

The questons should just be standard for a 1990 because the 383 I had build looked like the stock block as best I can tell. Can anyone answer these two questions for a stock 1990 C4 engine?

GREGGPENN

There was a C4 For Sale post for a DMF recently. Another thread was for a complete ZF trans. I saw them within the past couple of weeks. Those threads included good pics of the DMF. I'm thinking you could easily count the teeth from the pics.

I'm pretty sure you have a 1-piece seal.

rodj

Depends
You need to go back to the vendor and find out what block / crank combo is used and how it was balanced.Internal or external ?
Your stock setup WAS a DM flywheel and 153 teeth on a 1 pce seal block
Is the new engine built from a late model 1 pce seal block

What worries me is you say a 400 FW , which could indicate a 400 crank (2 pce) in a 350 block which only came as a 168 tooth.
If changing to a single mass FW then you have more options

Quick check
Is the crank flange where the FW bolts on completely round or does it have a counterweight?

Iroc57

I seem to remember 153
If your starter has inline bolts you should have 153

As far as one or two piece you just need the year of the block. 86+ should be one piece.

This is all from memory so I am sure that someone will chime in to confirm or correct me

rodj

You are missing the point ; as stated
"I bought a 383 shortblock from a vendor."
He apparently (looked like the stock block as best I can tell.) does not know what block / crank combo he has bought.

mgbss

If the back of the crank is round it is a 1 piece if it looks like it has two corners out of it is a 2 piece. The stock flywheel and the one your starter will fit is a 153 tooth.

Iroc57

He wanted to know what his flywheel was...I answered him

rodj

So did I ;in post # 3

Iroc57

Look at the time of the post

we were typing at the same time so I didn't see your reply until after I did it. Had I seen your reply I would have not posted so I ask...why did you direct a comment to me?

It is of no consequence so consider that a retorical question

"swamp rat"

Geez I just read this I'M sure YA'll did the best with the knowledge you had !!! So shake hands & make up !!! everybody has a opinion !!! PM ya know sometimes the thread does not tell you everything !!! Mother tereasa!!!