Which intake for Balance shaft vortec engine/Balance shaft removal?

CatriderF7

Petty Officer 2nd Class
Joined
Jun 8, 2011
Messages
126
So Im in the middle of an engine swap. the boat is a 1990 with a non balance shaft, non vortec 4.3. I bought a used 1993 Vortec 4.3L With balance shaft in it. The old 1990 intake doesnt fit it because it has a bulge that hits the balance shaft and keeps the intake an inch or two too high. So I ordered an intake off of a Vortec engine and the bump on the bottom of the intake is much smaller. (it looked flush in the pics on ebay) but its still too much and this one also hits the balance shaft.​
-
So what intake do I need to buy to not have this problem? Is just removing the balance shaft an option if I switch over the timing chain setup from the non balance shaft engine?
I had another post mentioning this but dont feel like trying to find it, and I think it started off as a different topic anyway.

I have a 1993, Balance shaft 4.3L to put in my boat. Problem is the original engine is a non balance shaft engine. And my intake off of that engine doesn't fit with the balance shaft. Is it possible to eliminate the balance shaft in my new engine so as it use the old mercruiser intake? I tried buying a newer style intake off ebay but it still doesn't clear the shaft. Only other option I see is to buy an edlebrock intake which is like $300. I paid $250 for the engine and am not willing to spend $300 on just an intake. So what I want to do is combine these 2 engines, using the old timing set. is this possible? I haven't taken them apart to see if everything will swap out easily or not. I also believe Ill have to plug the oil passage for the shaft after removing it but that wont be a problem as long as everything else swaps out easily​
 
Last edited by a moderator:

CatriderF7

Petty Officer 2nd Class
Joined
Jun 8, 2011
Messages
126
<a href="http://www.freeimagehosting.net/"><img src="http://i.imgur.com/XHhp0LB.jpg" alt="Free Image Hosting"></a>
 

CatriderF7

Petty Officer 2nd Class
Joined
Jun 8, 2011
Messages
126
No Title

Trying to upload pics but as always its being difficult. Every time Ive posted anything on here in the past month I get a message saying "Error" my post wasnt able to process or something to that effect.
 
Last edited:

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,932
I had another post mentioning this but dont feel like trying to find it, and I think it started off as a different topic anyway.

I have a 1993, Balance shaft 4.3L to put in my boat. Problem is the original engine is a non balance shaft engine. And my intake off of that engine doesn't fit with the balance shaft. Is it possible to eliminate the balance shaft in my new engine so as it use the old mercruiser intake? I tried buying a newer style intake off ebay but it still doesn't clear the shaft. Only other option I see is to buy an edlebrock intake which is like $300. I paid $250 for the engine and am not willing to spend $300 on just an intake. So what I want to do is combine these 2 engines, using the old timing set. is this possible? I haven't taken them apart to see if everything will swap out easily or not. I also believe Ill have to plug the oil passage for the shaft after removing it but that wont be a problem as long as everything else swaps out easily

Ayuh,.... I ain't tried it,.... You can be the 1st,..... Document it for others,...... ;)
 

CatriderF7

Petty Officer 2nd Class
Joined
Jun 8, 2011
Messages
126
Well I lied about taking pics. Phone was dead when I started working on it. But I did remove the gear that runs the balance shaft so as to make the balance shaft not rotate anymore and with that gear off I was able to turn the balance shaft in a certain way so that the weights are at their lowest point. And I was able to beat the heat shield (that goes up and over the balance shaft) down in the middle with a small sledge hammer and make enough room for the newer vortec manifold to sit and bolt down. With the original intake, which has a much larger bump on the underside, I would've had to remove the balance shaft altogether
 

CatriderF7

Petty Officer 2nd Class
Joined
Jun 8, 2011
Messages
126
Well I lied about taking pics. Phone was dead when I started working on it. But I did remove the gear that runs the balance shaft so as to make the balance shaft not rotate anymore and with that gear off I was able to turn the balance shaft in a certain way so that the weights are at their lowest point. And I was able to beat the heat shield (that goes up and over the balance shaft) down in the middle with a small sledge hammer and make enough room for the newer vortec manifold to sit and bolt down. With the original intake, which has a much larger bump on the underside, I would've had to remove the balance shaft altogether
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,537
I will do it for you

XHhp0LB.jpg
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,537
Personally, I wouldn't be doing what you are doing and just get the correct intake manifold.

You also don't have a Vortec. Vortec didn't come out until 1996 or so.
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
The balance shaft came around before the vortec did so a vortec intake should fit with balance shaft just fine.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,537
The balance shaft came around before the vortec did so a vortec intake should fit with balance shaft just fine.

He is trying to use his original no balance shaft intake with a balance shaft engine.

OP is very confused on Vortec and non Vortec engines. He doesn't have a Vortec engine or a Vortec manifold.

Here is his original thread:
http://forums.iboats.com/forum/engin...-vortec-engine EDIT - This link is going to loop back to this one since the topics were merged. GA_B.
 
Last edited by a moderator:

Idlespeedonly

Senior Chief Petty Officer
Joined
Jun 30, 2011
Messages
779
GM has been calling the 4.3 v6 engines VORTEC since the mid 80's.
But what everybody now considers a vortec engine would be the CPI and SCPI engine.
I believe these started showing up in 1992.
 
Last edited:

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,537
GM has been calling the 4.3 v6 engines VORTEC since the mid 80's.
But what everybody now considers a vortec engine would be the CPI engine.
I believe these started showing up in 1992.

http://en.wikipedia.org/wiki/General_Motors_90°_V6_engine

Major design changes to the 4.3L V6 for the 1996 model year. Like other small block Chevrolet V8s, the 4.3L engine received redesigned heads which had improved airflow and combustion efficiency. These heads are referred to as Vortec heads.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,537
Last edited:

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
Took the liberty to merge both topics. I had no trouble finding the first topic.
 
Top