To convert a Gbody v6-v8 - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Hotrodding Basics
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-08-2008, 08:04 PM
Registered User
 
Join Date: Nov 2005
Location: tx
Posts: 4
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
To convert a Gbody v6-v8

Basicly my olds cutlass had a sbc when i bought it a while back. I never worried about it. Today I went to look at a 86 v6 regal. The motor seems to be dieing. It Idles rough has a bad motor mount. And turns off when it goes in reverse. Also its an electric 2bl the owner says the problem is the carb which it may be because only black smoke comes out onces it is reved a good bit.

Any how Im wondering what would I have to do to get a v8 from a 86-up sbc in the g body?
I have a pretty good Idea so far.
New hoses
78-88 monte carlo mounts
accessories.

What else am i missing. I think the radiator will be fine.

Im not sure but it might be a 200r4 there but if its not what type of crossmember would i need to place a th350. I just need this thing roadworthy untill i can get a better set up.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-09-2008, 01:32 AM
curtis73's Avatar
Hates: Liver. Loves: Diesel
 
Last wiki edit: How to find cheap parts
Last journal entry: Found an LQ9 today
Last photo:
Join Date: Dec 2005
Location: Carlisle, PA
Age: 41
Posts: 5,289
Wiki Edits: 16

Thanks: 18
Thanked 16 Times in 12 Posts
The G-body is probably one of the easiest swaps to do with any GM engine. At one point or another, every GM V6 and V8 (except caddy) was installed in them from the factory, as well as multiple GM trannys including the TH350, THM200, THM200-4r, 700r4, and a couple other derivatives of those. So, instead of sweating the little things, GM made provisions for every engine and almost every tranny in every G-body.

Basically, every G-body has the same frame, so if you got an El Camino with a 305/200C, it was the same frame as a Grand National with a 3.8 turbo and 200-4r, and the same as a Monte Carlo with a V6/TH350. The frame is drilled for the multiple tranny crossmember possibilities, and the engine mounts are drilled for multiple GM engines.

Its pretty much as simple as buying the right motor mounts, moving the tranny crossmember where it needs to be, and then working out the details. Across the GM family, things like starters, alternators, distributors, sensors, and fuel pumps were on different sides of the engine. You might have to extend certain wires and shorten some, or extend a fuel line to the other side of an engine, but otherwise the swap is gravy with mashed potatoes.

There are also common aftermarket kits to make Caddy engine mounts work, and I've seen several Caddy 500s in G-bodies. There is also a ton of tech on the web about swapping in manual trannys. The factory did such a small number of manuals in G-bodies that its not common to just find a junkyard swap, but many folks have put T5s, T56s, T10s, and many other common manuals in G-bodies using common, off-the-shelf parts.

To me, the G-body is the ultimate easy swap car.... so easy that I wanted to swap a 302 Windsor into my 87 Cutlass just to be different.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-09-2008, 06:01 AM
Registered User
 
Join Date: Nov 2005
Location: tx
Posts: 4
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks guy, I looked through some more google searches and found exactly what I needed but it never hurts to get some GOOD extra advice. Just wondering though would I need to get the drive shaft balanced/shorted or is that where the " moving the transmission crossmember to fit " come in?

Oh btw sbf cutlass that made me smile.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-09-2008, 10:24 AM
1ownerT's Avatar
Home School Valedictorian
 
Last wiki edit: Health and safety in the shop or garage Last photo:
Join Date: Dec 2004
Location: Iowa
Age: 53
Posts: 1,645
Wiki Edits: 4

Thanks: 0
Thanked 3 Times in 3 Posts
If going from a TH 350 to a 200 R4 or the reverse, the driveshaft is the same.
I had a G body Monte with a turbo 3.8, changed it out with a 355. I was able to reuse the pads on the crossmember for the engine mounts. I did have to relocate them though, the holes are there already. It is a PITA to get to the nuts on the inside of the crossmember though.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 10-09-2008, 06:22 PM
curtis73's Avatar
Hates: Liver. Loves: Diesel
 
Last wiki edit: How to find cheap parts
Last journal entry: Found an LQ9 today
Last photo:
Join Date: Dec 2005
Location: Carlisle, PA
Age: 41
Posts: 5,289
Wiki Edits: 16

Thanks: 18
Thanked 16 Times in 12 Posts
Across the g-body line, GM engine/tranny combos always meet at the same point. That is to say, regardless of what engine you use, it will always have the tranny flange at the same point. So, if you are swapping transmissions, the length of the tranny itself will be the most important. The 200, the 200-4r, and the short tail 350 are all the same length and use the same output shaft, so swapping between those three can use the same driveshaft. The difference with those trannys is where the tranny mount is. Even though they are the same overall length, the mount on the 350 is much further forward on the tranny. That's why you might have to move the crossmember.

Take a look here:


Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 10-10-2008, 04:30 PM
Registered User
 
Join Date: Nov 2005
Location: tx
Posts: 4
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
wow that chart is so good it should be a read me somewhere
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 10-10-2008, 05:53 PM
curtis73's Avatar
Hates: Liver. Loves: Diesel
 
Last wiki edit: How to find cheap parts
Last journal entry: Found an LQ9 today
Last photo:
Join Date: Dec 2005
Location: Carlisle, PA
Age: 41
Posts: 5,289
Wiki Edits: 16

Thanks: 18
Thanked 16 Times in 12 Posts
It is...

Transmission Information.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 10-11-2008, 06:06 AM
Registered User
 
Last wiki edit: How to title a hot rod Last photo:
Join Date: Feb 2007
Location: West Virginia
Age: 25
Posts: 3,393
Wiki Edits: 8

Thanks: 16
Thanked 1 Time in 1 Post
3.8s will work with normal gen 1/gen2 transmissions right?

Shane
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 10-11-2008, 08:47 AM
1ownerT's Avatar
Home School Valedictorian
 
Last wiki edit: Health and safety in the shop or garage Last photo:
Join Date: Dec 2004
Location: Iowa
Age: 53
Posts: 1,645
Wiki Edits: 4

Thanks: 0
Thanked 3 Times in 3 Posts
Quote:
Originally Posted by Chevrolet4x4s
3.8s will work with normal gen 1/gen2 transmissions right?

Shane

Not sure what you are referring to.
In my case, the Monte had a Buick 3.8 w/TH350. I changed the trans first to a 200 R4, dual pattern. Then later changed the 3.8 for a 355, used the same trans and drive shaft. I used the cross member from the 87 Monte donor, and made a bracket for the passenger side frame rail on the 80 Monte, since they did not have the OD trans in 80.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 10-11-2008, 09:35 PM
Registered User
 
Last wiki edit: How to title a hot rod Last photo:
Join Date: Feb 2007
Location: West Virginia
Age: 25
Posts: 3,393
Wiki Edits: 8

Thanks: 16
Thanked 1 Time in 1 Post
Thats what I was needing to know..I forgot to add V8 after gen1/gen2

Thanks
Shane
Reply With Quote Quick reply to this message

Recent Hotrodding Basics posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
V6 TBI in a V8 ???? Augusto Engine 12 11-15-2007 10:46 PM
V6 or V8 700R4 swap? cacsmret Transmission - Rearend 4 05-05-2006 10:28 PM
Engine Swap 1987 Pontiac Firebird V6 to V8 bccsrc Engine 12 01-15-2006 07:01 PM
V6 to V8 mini van ? bowtieorbust Engine 13 01-16-2004 08:27 PM
Convert From V6 to V8 in 86 camaro??? 1986 Camaro Engine 4 10-14-2002 01:29 PM


All times are GMT -6. The time now is 11:35 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.