81 grand prix v6 to 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> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-12-2004, 01:28 PM
Member
 
Last photo:
Join Date: Oct 2003
Location: jacktown
Age: 28
Posts: 110
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
81 grand prix v6 to v8

I have a 81 grand prix with a 231 v6 engine and I was thinking about changing the motor to a v8. I finally found a motor in a monte carlo I think the motor is a 305.. What all do I need from the monte carlo so I can drop the motor in my 81 grand prix?
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-12-2004, 04:19 PM
DoubleVision's Avatar
Not Considered a Senior Member
 
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 40
Posts: 10,643
Wiki Edits: 0

Thanks: 13
Thanked 56 Times in 53 Posts
Motor mounts, cross member, fan shroud, radiator, some fuel line routing from drivers to passengers side for fuel pump, exhaust, some minor wire rerouting, and you`ll need the front coil springs, the V8 will make the front end drop by about a inch or more and will effect handling, for your safety swap the coil springs. Other than this, it`s pretty much a direct forward slam dunk swap, did many like it into Olds Cutlasses. If you plan to have A/C you`ll need the monte`s system as well.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-12-2004, 06:46 PM
Member
 
Last photo:
Join Date: Dec 2003
Location: over there, next to that.
Posts: 210
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Are you set on getting the 305?


It would be a good idea to hold out for a 350. They aren't hard to find and they are cheap, best part you'll have a better base to build off of. It may be tempting to jump in and get the 305 have that v8 sound, but don't give up there are 350's everywhere.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-12-2004, 07:21 PM
Lonestar's Avatar
"May the Schwartz be with you"
 
Last wiki edit: How to rebuild an engine
Last journal entry: Finally getting going...
Last photo:
Join Date: Aug 2004
Location: United States
Age: 43
Posts: 1,054
Wiki Edits: 1

Thanks: 0
Thanked 0 Times in 0 Posts
I agree with 357ford, why do all the work for a pathetic little 305. Find a 350 at least. It's just not worth it otherwise.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 10-12-2004, 08:53 PM
Member
 
Last photo:
Join Date: Oct 2003
Location: jacktown
Age: 28
Posts: 110
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Im not planning on racing the car I just want a v8 engine so I can put some flowmasters on it. Thanks for the help.....do u think a shop would charge over 400.00 to swap the motors?
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 10-13-2004, 10:20 AM
Member
 
Last photo:
Join Date: Feb 2004
Location: Halifax, NS
Posts: 189
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Getting a 305 for the sound alone is a waste of money.
It will burn more gas without giving you the power of a 350, although it will give you the weight to lug around.
That's like buying aftermarket parts just to put thier stickers on a car.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 10-13-2004, 07:39 PM
Member
 
Last photo:
Join Date: Oct 2003
Location: jacktown
Age: 28
Posts: 110
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
But I feel like im getting a deal the motor and transmission for 350.00 well actually the whole car.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 10-13-2004, 07:45 PM
Member
 
Join Date: Feb 2003
Posts: 37
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
transmission

May want to keep the pontiac tranny if it is a 200R4 with overdrive. It should have a combo chevy and BOP bolt pattern so both the 305 or 231 would fit.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 10-13-2004, 09:08 PM
Member
 
Last photo:
Join Date: Oct 2003
Location: jacktown
Age: 28
Posts: 110
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I think the trans is a bop 350 i dont think it will fit chevy
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 10-14-2004, 12:02 AM
Grumpy
 
Last photo:
Join Date: Dec 2002
Location: D.C.
Posts: 1,450
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
It's a bit more than some people think. Exhaust system has got to go, different suspension, sway bar, (as said) springs, mounts, wiring. Am I missing anything.

The biggest hangup is the suspension system. Just look under the back of any V6 cutlass and than look at the back of any V8 cutlass, you should start to see the differences. Also different rear ends in some. A V6 model will more than likly have the 7.5" when some V8's got the 7.625's and 8.5" rear ends and all performance cars got the 7.625", and 8.5" rear ends.

It is much cheaper to find another 81 pontiac with the V8 setup already there.

Just my 2 cents on the swap.

Do what I'm doing on this V6 cutlass I have, swapping the exhaust from a dead cutlass V8 I have sitting, installing a cam, 4bbl intake, trans, and gearing. It might only get to the 17's or 18's if I'm lucky, but so would a stock 305 pontiac or cutlass. Plus I'm getting all this done for almost nothing.

There's a different view of it for ya.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 10-15-2004, 11:35 AM
Member
 
Last photo:
Join Date: Oct 2003
Location: jacktown
Age: 28
Posts: 110
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
And one more thing how will I hook the speedometer back up......would I just run a line straight from the speedometer to the side of the transmission where the speedogear is?
Reply With Quote Quick reply to this message

Recent Engine 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:
If you do not want to register, fill this field only and the name will be used as user name for your post.
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



All times are GMT -6. The time now is 01:31 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.