LUVTruck.com

phpBBV3 Message Board
It is currently Fri Mar 29, 2024 6:33 am

All times are UTC - 6 hours




Post new topic Reply to topic  [ 5 posts ] 
Author Message
PostPosted: Sun Sep 27, 2015 11:10 am 
Offline
Addicted to LUV
User avatar

Joined: Thu Jan 21, 2010 11:47 pm
Posts: 2944
Location: Vancouver, Washington
Does anyone know if there is a difference between the header flanges on the pre vortec 95- and the vortec 96+ v8 and 4.3 v6 engines? I was looking at 4.3 header flanges on eBay and there are only a few and none specified for vortec heads they just say rwd, 1978+ Chevy & gmc, 3.8 and 4.3 non BOP engines.. looking at pictures of the heads they dont look very different on the exhaust side but I'm not sure if the ports are bigger or the spacing is different

any idea? later down the line i would like to weld up a different header layout so I'm trying to plan for the overall cost and where I can get parts

If they are cross compatible I can use the 4.3 specific ones. If not I can just as easily get flanges from a vortec v8 and cut off the extension to one outside port on each.

_________________
Luvless :(
1980 Mikado-Sold.

1993 Lexus SC400 my Daily
2004 Yamaha WR250F my new love in life
2016 Toyota Camry my girls ride


Top
 Profile  
Reply with quote  
PostPosted: Mon Sep 28, 2015 8:58 pm 
Offline
lives at LUVTruck.com

Joined: Sat Feb 21, 2009 12:57 am
Posts: 357
Location: Minden, Nevada
The SB V6 heads from the production factory are all basically the same castings. The 18* heads are close. You cannot cutoff one end of a V8 flange. However you could cut the two ends off of three V8 flanges. If your lucky you might score a set of spayed valve V6 heads $$$$$.
www.powerbyace.com has the SAP flanges available for 1 5/8" tubes.

_________________
The light at the end of the tunnel, may just be a train coming!


Top
 Profile  
Reply with quote  
PostPosted: Mon Sep 28, 2015 9:27 pm 
Offline
Addicted to LUV
User avatar

Joined: Thu Jan 21, 2010 11:47 pm
Posts: 2944
Location: Vancouver, Washington
The 96+ vortec heads have bigger and different shaped intake ports and a different chamber shape based on lt1 heads vs the old swirl port heads my concern is for a change in the exhaust port size to match the other changes headers etc are listed pre and post 96 usually so I'm trying to figure out what changed

Why would I need 3 flanges? The heads are the same as the v8 minus a cylinder if I cut off one front and one rear port from a pair of v8 flanges they should line up with the v6 ports as far as I can tell. Same goes for intake manifolds if you have the time to cut down a v8 sheet metal intake it will fit a 4.3.
Looking at long term build ideas and regardless a good 1/2" flange would be good to have.

_________________
Luvless :(
1980 Mikado-Sold.

1993 Lexus SC400 my Daily
2004 Yamaha WR250F my new love in life
2016 Toyota Camry my girls ride


Top
 Profile  
Reply with quote  
PostPosted: Tue Sep 29, 2015 1:09 pm 
Offline
lives at LUVTruck.com

Joined: Sat Feb 21, 2009 12:57 am
Posts: 357
Location: Minden, Nevada
The cylinders that were removed were #5 & #6. These ports were rear of the two center ports. Just cutting the ports off of a V8 flange, you would also be missing a needed mounting bolt. The V6 has no conjoined ports as does the V8, it has three individual ports with two bolts per port.
If you can find a copy of "Chevrolet Power" 1994 GM# 24502488 has blueprints for the V8 and V6 heads, V6 pg# 158.
You also might find the inside cover to be very interesting reading.
1/2" for an N/A engine is extreme overkill. Due to the port separation 5/16" will handle anything you need. The thick flanges are need for the lack of cooling between the center ports. If you're thinking of hanging a turbo onto the flange with no additional support, you'll also want too use 14ga tubing to prevent cracking at the welds to the flange.


Attachments:
6132 Chevy SB Header gskt.jpg
6132 Chevy SB Header gskt.jpg [ 73.21 KiB | Viewed 3479 times ]
6136 Chevy 4_3L V6 header gskt.jpg
6136 Chevy 4_3L V6 header gskt.jpg [ 64.01 KiB | Viewed 3479 times ]

_________________
The light at the end of the tunnel, may just be a train coming!
Top
 Profile  
Reply with quote  
PostPosted: Tue Sep 29, 2015 9:52 pm 
Offline
Addicted to LUV
User avatar

Joined: Thu Jan 21, 2010 11:47 pm
Posts: 2944
Location: Vancouver, Washington
Ahhh I see I was thinking the v8 had the same spacing as the 2 close together v6 ports for some reason.
And I am considering a supercharger/lpg build later on down the line which is why I thought 1/2" would be ideal.
Thank you for the information I was way off

_________________
Luvless :(
1980 Mikado-Sold.

1993 Lexus SC400 my Daily
2004 Yamaha WR250F my new love in life
2016 Toyota Camry my girls ride


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC - 6 hours


Who is online

Users browsing this forum: Google [Bot] and 17 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group