4.3L Vortec to Carb Conversion? - 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 05-13-2013, 09:07 AM
jaw22w's Avatar
Registered User
 
Last photo:
Join Date: Oct 2011
Location: Indiana
Age: 64
Posts: 141
Wiki Edits: 0

Thanks: 12
Thanked 2 Times in 2 Posts
4.3L Vortec to Carb Conversion?

I have a 1926 T coupe that I would like to put a 4.3 chevy v6 in. I have a line on a 48k mile 2000 4.3L vortec engine. My engine knowledge ends with carb motors. My question is: Can I remove all the electronic injection stuff and replace it with a manifold and carb? Edelbrock has a 4 bbl. manifold #2114 that looks to fit the vortec v6 heads. Is this as simple to install and run as it seems? What size carb should I run? Edelbrock recommends a 500 cfm unit. I want to run a 700 r4 trans. Can this be done with the edelbrock 500 cfm carb?
Also, what needs to be done for the ignition? I assume the ignition is controlled by the computer, so just replace the existing distributor with a hei?
I don't want any computers on this car as I just don't understand them. I appreciate any help you engine gurus an give me.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 05-13-2013, 10:12 AM
Registered User
 
Last photo:
Join Date: Nov 2006
Location: Woodstock
Posts: 894
Wiki Edits: 0

Thanks: 2
Thanked 72 Times in 66 Posts
Sounds like you got a handle on it.

The 4.3 in the 1996-1999 full size GM trucks was rated at 200hp/260lb/ft torque. TBI 350's were rated at 190-210hp with 300 lb/ft torque.

My g-friend had a 4.3 V6 reg cab shortbox 2wd , 4l60e auto, 3.08 rear geared 1997 Chev pickup. I had 1992 reg cab 2wd, 700r4 auto, 3.08 geared truck but with teh TBI 350 engine. We would drag race adn I would get up on her out of the hole, but she would always walk by my truck before the end of the 1/4 mile.
Thats when I sold my 92 rcsb and bought myself a 1997 reg cab shoprtbox 2wd truck which ran a best of 14.8@94 with 2.007 60ft time. Bottom line, the 4.3 L35 you have will work cvery well in your light car.

Personally I would just run the EFI. Just use the PCM from the engine, run a high pressure pump that will feed at least 66 psi to the engine. The throttle response from an injected L35 V6 will be lost with a carb, but its your truck.
The 700r4 requires a TV(throttle Valve) cable to control line pressure and shifting. It mounts around teh carb and attaches to the carbs throttle arm

here is some Lokar stuff that wil work
Buy Lokar Throttle Valve Cables and Brackets from PATC

Not 100% sure if there is a mechanical fuel pump provision on teh 4.3 Vortec block, you may have to run an intake or inline low pressure pump regulated down to 8 psi to the carb.

A standard V6 HEI distributer will work fine for you.

Grab a carb with an air cleaner/breather ****embly.

Exhaust manifolds or V6 headers will work.
You may need to leave some sensors in the holes to prevent coolant/oil leaks.

You must use a squarte bore carb with the 2116 intake manifold
http://www.summitracing.com/parts/ed...s/?prefilter=1

The 4.3 is a 350 mius 2 cylinders, so a 500cfm carb is more than enough, just match it up to your intake.

Be sure you get good intake manifold gaskets, teh stock ones have been reworked a few times by GM. felpro makes a very nice aftermarket set with strong metal inserts, but they are expansive.
QMS98002T by Felpro these also come with upper and lower intake gakets as well as the centerbolt valvecover gaskets Unfortunately you cant get these lower intake manifold gaskets by themselves.
$85
http://www.summitracing.com/parts/fe...make/chevrolet

Stock type impregnated silicone gaskets by Felpro these also come with upper and lower intake gakets as well as the centerbolt valvecover gaskets
QMS95817 $42
http://www.summitracing.com/parts/fe...make/chevrolet

You need to run good intake gaskets because, unlike older 4.3's the Vortec 4.3's and V8's use an intake manifold that has 8 intake manifold bolts which sit at 90 to the ground instead of 90 to the gasket face. This puts the gaskets in a constant state of sheer once torquyed. Then as teh engine heats up the aluminum lower intake expands more than the cast iron cylinder head causing the gasket to "roll", then it rolls agains as the setup cools. So every heat cycle causes this to happen. Eventually teh stock gaskets fail. These Vortec engines are notorious for intake manifold gaskets. On my Vortec 350(same setup as your engine) I have used the more expensive kit and havent needed new gaskets in over 100,000 miles. And that is on my 3 trucks all of which have Vortec 350's. The stock gaskets let go within 100,000 miles on average.
Stock style failed 4.3/5.0/350 intake gasket


Improved Felpro 350 gaskets, same construction of the improved Felpro 4.3 gaskets


This is a pic of a Dorman improved heater hose connection that screws into the intake manifold, this is made of better metal than teh stock connection. The stock material was pot metal and would easily break off. This is a much better piece.


But I suggest you use a standard water nipple such as this type.


Coolant comes out of the intake manifold through this nipple and feeds into the heater core.



The 4.3 should work very well for you.



peace
Hog
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-13-2013, 12:34 PM
jaw22w's Avatar
Registered User
 
Last photo:
Join Date: Oct 2011
Location: Indiana
Age: 64
Posts: 141
Wiki Edits: 0

Thanks: 12
Thanked 2 Times in 2 Posts
Wow Hogg! Thanks so much for the information. That is exactly what I needed. As you said you prefer, I would run the EFI, but I would have no idea how to hook it all up, plus the engine does not come with the PCM. I know I will give up a little performance, but this is just a nice little cruiser. If I need an adrenaline rush I get in my 27 T roadster. 2000 lbs. with 450HP. I am surprised that the v6 vortec would outrun the 350 on the big end.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 05-13-2013, 02:24 PM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
I'd want to use an aftermarket intake, but there are a few OEM options.

Some Chevy V6 info here.

I'd have to add that unless engine length were important, using a SBC V8 would be as cheap if not cheaper and will make more power all else being equal.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 05-13-2013, 03:57 PM
jaw22w's Avatar
Registered User
 
Last photo:
Join Date: Oct 2011
Location: Indiana
Age: 64
Posts: 141
Wiki Edits: 0

Thanks: 12
Thanked 2 Times in 2 Posts
Quote:
Originally Posted by cobalt327 View Post
I'd want to use an aftermarket intake, but there are a few OEM options.

Some Chevy V6 info here.

I'd have to add that unless engine length were important, using a SBC V8 would be as cheap if not cheaper and will make more power all else being equal.
I am leaving the car full fendered and the radiator in the original position. There is only 27" available in the engine bay. 31.5 " is needed for a sbc. I don't want to cut the firewall. So, length is the deciding factor and as stated above I don't want a lot of hp in this car. It is just for cruising. My wife may drive it. I don't trust her with a lot of power and I already have an adrenaline rush hot rod.
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
Vortec Head Conversion 1972RedNeck Engine 2 01-05-2011 04:33 PM
L31 Vortec Conversion to Carb. Ct Street Rod Engine 10 07-25-2010 06:21 PM
carb/fuel injected intake to vortec tb conversion plate 383silverado Engine 5 09-09-2007 10:36 AM
vortec conversion ? slim69 Engine 1 11-08-2004 08:40 PM
4.3L vortec conversion fightingcody Engine 3 05-18-2002 09:41 PM


All times are GMT -6. The time now is 12:39 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.