Vortech to TBI swap questions... - 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 01-16-2011, 08:04 AM
Registered User
 
Join Date: Jan 2011
Location: Luzerne,Mi
Posts: 3
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Vortech to TBI swap questions...

I have a 1991 GMC Pickup with a TBI motor that has a spun bearing..I have 99 Chevy Express Van with a vortech 350 that I would like to swap the motor out of as cheaply as possible and I have some questions..

Heads/Intake: What would I need to swap the TBI heads onto the Vortech motor so I can keep everything else (Intake) stock..Will this even work?

Tranny: They both have the 4L60E although one is 4wd and the van is 2wd..I presume this doesnt matter as far as bolting up

Exhaust: Would everything be the same from the Vortech over to the pickup?

Any other major issues I might encounter as far as fuel pressure...Head squish..Deck Height?

Thanks Trent

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 01-16-2011, 08:26 AM
How fast is fast enough?
 
Last photo:
Join Date: Jun 2005
Location: St. Louis, MO
Age: 29
Posts: 9,108
Wiki Edits: 0

Thanks: 17
Thanked 335 Times in 315 Posts
If you just want to change shortblocks that shouldn't be a problem, it should all just bolt right up.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 01-16-2011, 09:29 AM
Registered User
 
Join Date: Jan 2011
Location: Luzerne,Mi
Posts: 3
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
What size head gaskets would I need to get? Thanks Trent
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 01-16-2011, 02:18 PM
Registered User
 
Last photo:
Join Date: Sep 2008
Location: louisana
Posts: 225
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
ther is a tbi intake that will fit the vortec heads. thats how i would go. most bang for the buck. I think but not sure you can modify you intake to make if fit, but heard its not realy right.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 01-16-2011, 03:53 PM
Registered User
 
Join Date: Jan 2011
Location: Luzerne,Mi
Posts: 3
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
That is why I am swapping the heads..Thanks
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 01-16-2011, 04:19 PM
Registered User
 
Last photo:
Join Date: Sep 2008
Location: louisana
Posts: 225
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I think just put the intake on the van 350 and drop it in your truck. why open a good motor just to give it less power. if you do the intake all you have to have is the intake gaskets. If you elongate your middle holes in the intake you can bolt it on. if the vortec intake is to much find you an duel plan intake that would bolt to the vortec and us adapter plat. If I could help it i would not take those heads off. your other option is since you have the complete van just transfer all the fi from the van to the truck
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 01-16-2011, 11:54 PM
Member
 
Last wiki edit: Ford axle ratio codes
Last journal entry: Rear Suspension
Last photo:
Join Date: Aug 2005
Location: Prattsville
Posts: 6,389
Wiki Edits: 31

Thanks: 2
Thanked 58 Times in 54 Posts
I would not put the TBI heads on the vortech shortblock.. the pistons are diffrent because of the heads, and it will lower the compression.. a kid I went to autoshop class with, did the same thing. had a Vortech 350 short block, did a re ring and bearing, and stuck the TBI heads on it. I warned him, that it wasn't gonna run good and he should have gotten the GMPP or Edelbrock conversion manifold ( back when Eddy was still making them )... that truck didn't even idle right, because the stock cam had become too big for the engine due to the compression being so low.. no power and threw a CEL for the MAP sensor
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 01-17-2011, 08:32 AM
Registered User
 
Join Date: Nov 2010
Location: Lynchburg Va
Posts: 133
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Leave the Vortec motor alone, either buy a edelbrock TBI Vortec intake, or buy a Carb intake for vortec and an adapter.

Seriously the best bang for the buck.

Then strip the TBI motor and pray its a 4-bolt 1pc roller, and sell it for 100 Bucks.

Scrap the rest.

As to swaps exhaust manifolds and everything will bolt up, if it bothers you, change the timing covers Vortec's have a Crank sensor and a plastic cover your TBI motor I don't think does. and you need to use your TBI distributor.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 01-17-2011, 08:33 AM
Registered User
 
Join Date: Nov 2010
Location: Lynchburg Va
Posts: 133
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
if you want swap a GM performance roller cam compatible with TBI and long tube headers as well :-) then maybe a Holley 670CFM TBI unit (its bolt on) and reflash your ECM
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 01-17-2011, 11:48 AM
Registered User
 
Last photo:
Join Date: Apr 2007
Location: Seattle, Wa
Posts: 6,852
Wiki Edits: 0

Thanks: 4
Thanked 457 Times in 392 Posts
Quote:
Originally Posted by thek5king
I have a 1991 GMC Pickup with a TBI motor that has a spun bearing..I have 99 Chevy Express Van with a vortech 350 that I would like to swap the motor out of as cheaply as possible and I have some questions..

Heads/Intake: What would I need to swap the TBI heads onto the Vortech motor so I can keep everything else (Intake) stock..Will this even work?

Tranny: They both have the 4L60E although one is 4wd and the van is 2wd..I presume this doesnt matter as far as bolting up

Exhaust: Would everything be the same from the Vortech over to the pickup?

Any other major issues I might encounter as far as fuel pressure...Head squish..Deck Height?

Thanks Trent
Oh boy where to start?

Tranny the 91 would have a 700R4 which became identified as 4L60 and trips up a lot of people because of the electronic version the 4L60E that came out in 1993. The 700R4 and 4L60 are the same transmissions which have mechanically controlled hydraulics; where the 4L60E is mechanically the same as the 4L60 but has electronically controlled hydraulics. so the tranny you have is not the 4L60E, at least not what the factory put there.

Your existing 91 would have the TBI swirl port engine whether 305 or 350. At a very basic level if the existing engine is a 350, then the swap engine also being a 350 will not require a changed chip in your existing computer. However, the 99 has that central port Vortec injection and runs off what's called OBD II computing, where the 91 has Throttle Body Injection (TBI) and OBD I computing. Nothing between these systems is compatible right down to the fuel pump.

What you can do is a lot.

1) You could use the Vortec bottom end with your swirl port heads and TBI system again 350 to 350 if not some messing with your 91 computer will be necessary for the additional 45 cubes that have to be fed over a 305. This swap saves money in a new intake but can't take advantage of the more efficient and powerful Vortec heads of the 99.

2) Use the 99 L31 and adapted it to TBI. This takes a GM intake 12496821 which connects the vortec heads to the TBI and has EGR. However, the Vortec heads have no exhaust cross-over so are unable to feed the EGR in the same way as the Swirl Port heads. This is solved by patching a fitting into the exhaust and running a tube to a fitting on the intake. Once upon a time Edlebrock and GM sold the parts to make this happen, but today this is a case of getting fittings and tube at your local home improvement center. This intake is a bit pricey, but being this is a pick up there's a lot of air cleaner to hood clearance so another way to go is with an aftermarket 4 barrel to Vortec head and a carb flange to TBI adapter which may prove to be a little less expensive approach. You'll still have to fab an EGR source if you keep it. Be aware that terminating the EGR will have bad effects on passing emissions if you must. It also causes the mixture in the engine to be lean unless a new chip that corrects for the missing function is installed to the computer. You will use the existing distributor and coil from your TBI engine. The L31 will have a crankshaft sensor on the timing cover, the TBI has no use for this so just coil and stow the wire and connector from it if you don't remove it altogether.

3) Swapping the L31 stuff from the van into the 91 can be done but it is really time consuming. All the engine management and functional systems right down to the fuel pump and all the wiring for all the systems would have to be swapped in, this is a huge job, not impossible, but most who tried greatly underestimated what they were up against. But this would let you use the L31 and its OBD II systems

Bogie
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
cam questions with vortech heads buskey Engine 7 12-27-2009 11:21 AM
TPI Swap Questions hzemall Engine 0 05-09-2009 01:25 PM
Cam swap Questions wayfast77 Engine 3 10-18-2006 04:52 AM
lt1 swap questions sb motorsports Engine 1 11-15-2004 10:44 PM
327-454 Swap Questions. Coleman396 Engine 0 10-12-2003 09:14 AM


All times are GMT -6. The time now is 04:10 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.