***Login to the Forum here ***

Support FSC and see no ads! - Click Here
Page 2 of 3 FirstFirst 123 LastLast
Results 21 to 40 of 57
Like Tree1Likes

4.3 to 350 swap

This is a discussion on 4.3 to 350 swap within the Engine Swaps forums, part of the Projects and Builds category; Can you return the intake? if not there is another way. Using the new intake as a drill guide you ...

  1. #21
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap


    Support FSC and see no ads! - Click Here
    Can you return the intake? if not there is another way. Using the new intake as a drill guide you can drill out the middle holes straight down using a Helicoil repair kit. using the kit just drill, tap, insert the thread repair and your done.

    I converted a set of TBI heads to standard intake type on a hotrod project once. But once it's done it's done, you can't go back.

    If you use a TBI adapter on a 4BBL intake you'll have endless intake options if you want to modify the system later, like adding a big block TBI.

    In fact the early TBI 454's used an adapter for the spread bore intakes. GM didn't have a dedicated big block TBI intake intill the early 90's.

  2. #22
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    any idea how much one of those kits are?

  3. #23
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap

    You can pick up a helicoil kit at AutoZone for $21.99

    http://www.autozone.com/autozone/acc..._&viewAll=true

  4. #24
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    is there any way i could possibly run a carb on the truck without having to mess with all my electronics and stuff( wipers, ignition etc)

  5. #25
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap

    I had a 1989 S15 that came with a 4.3. I converted it to a V8. I went through a lot of trouble hacking into the harness trying to convert to a carb. It was my first (S-10) V8 swap and made a LOT of mistakes. If you really want to go with a carb you'll need a repair manual and study the harness well. You'll need to very carfully take the harness apart to get ride of what you don't need. There is a green wire that feeds you temp guage. I think it's a small purple wire that works your oil pressure guage from the back of the engine. If you use an HEI dizzy be carefull what ignition circuit you connect it to. I accidently powered it from the HON switch circuit. That kept it energized even when I turned off the ignition. Keep the HON switch and oil pressure switch circuit intact. You need that for the fuel pump. Unlike EFI when you turn off the ignition on a carb engine you can ONLY kill the spark, the fuel is still flowing through the carb as long as there is gas in the bowl. You'll also need a bypass regulator to get the fuel pressure down to 6 PSI. DONOT use those cheap autoparts store regulators, you'll fry the pump. You'll have to fabricate some fuel lines too. Do not use cheap rubber hoses. Getting all the other stuff to work right will take patience.

    Just remember this, your truck will get real crappy gas mileage. 12 to 14 miles per gallon. This is not a weekend engine swap. Get all your parts together and a real good plan first before you disable your truck.

    I almost forgot, you'll need to change the engine mounts. To do that you'll have to remove both the lower suspension arms to get a wrench on the nuts of the motor mount bolts.

    Going from EFI to carb looks easy but is more trouble than it apears.

    Everything you need for a V8 EFI is already in your truck. Just find a U-Pull-It yard and get a V8 TBI, dizzy, and a 94-95 5.7L truck ECM. Pull the manifolds and Y pipe too. You'll need a V8 radiator and fan shroud, and hoses. All the other sensors that are on your V6 will bolt to the V8 in the same locations. You'll just need to lengthen a few wires. Swap the Cam and lifter set to a stock 94 5.7 for about $150 bucks or less.

    You can make this work. It's not as hard as you think it is.
    Last edited by dualtbi88; 12-23-2010 at 10:26 PM.
    Paul R
    88 Step Side Modified ZZ4 Offenhauser Cross Ram dual TBI, Crane roller cam, FJO injector driver. Hand built serpentine drive.
    still under construction

  6. #26
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    thanks ive run into a problem now finding a flywheel, i need one that will fit my transmission but has to fit the 350, its a 78 model block any suggestions?

  7. #27
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap

    OOPS... I forgot that your using a stick. I had to update this post for that.

    You can pick up a standard neutral balanced flywheel at any auto parts store for a small block chevy 1985 thru 1955. Your block has a 2 piece rear main seal and is internally balanced. The bolt pattern is 3.58 x 6. Most autoparts stores look up parts by vehicle description.

    Just make shure it has the same diameter as your V6 flywheel. You may need to get a flywheel for a 1984 vette.
    Last edited by dualtbi88; 12-28-2010 at 02:27 PM.

  8. #28
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap

    Paul R
    88 Step Side Modified ZZ4 Offenhauser Cross Ram dual TBI, Crane roller cam, FJO injector driver. Hand built serpentine drive.
    still under construction

  9. #29
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    its been a while since ive posted but got the motor in and its runnin on open headers right now (until i can get a set of longtubes so i dont pay to have my exhaust fixed twice) but i found out the hard way my slave cylinder wasnt in line, and i never wouldve imagined the power steering pump pulley could be this big of a pain, we thought it was on good, the belt lined up and everything went smooth the first 2 or 3 minutes of runnin it then the belt wrecked and the pulley nearly flew off, (so now im out another $30 for a new belt)
    anyone have any suggestions on the pulley? any help would be greatly appreciated

  10. #30
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap

    So what type of belt drive are you using? Did you go with the carb and HEI?
    Last edited by dualtbi88; 01-12-2011 at 01:45 PM.

  11. #31
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    nah im runnin the serpetine system
    and just drilled the tbi intake

  12. #32
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap

    So how did it go as far as the EFI conversion from the 4.3?

  13. #33
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    i just bolted the throttle body from the 4.3 down to the intake and used the same injectors and such yet to locate a v8 throttle body locally

  14. #34
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap

    there is a U-pull it about 40 miles from my house. I can see if they have any. If they do I can send it to you. Did you have much trouble getting the v8 distributor?
    Paul R
    88 Step Side Modified ZZ4 Offenhauser Cross Ram dual TBI, Crane roller cam, FJO injector driver. Hand built serpentine drive.
    still under construction

  15. #35
    FastOrange BlacK20's Avatar
    Join Date
    Nov 2010
    Location
    Williams Lake, BC!
    Age
    22
    Posts
    2,253

    Re: 4.3 to 350 swap

    Try to stay EFI, a carb swap isnt THAT hard, i went from a TBI 4.3L to a Carb 350, but its alot of tedious Bull**** wiring.


    1978 K20 RCLB, 400 SBC, 4-Speed, Lifted
    1998 Pontiac Grand Prix GT, Coupe

  16. #36
    FastOrange BlacK20's Avatar
    Join Date
    Nov 2010
    Location
    Williams Lake, BC!
    Age
    22
    Posts
    2,253

    Re: 4.3 to 350 swap

    opps, just saw that you stayed EFI, also a 4.3L TBI is the EXACT same as a 350 one, Injectors are only difference.


    1978 K20 RCLB, 400 SBC, 4-Speed, Lifted
    1998 Pontiac Grand Prix GT, Coupe

  17. #37
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    theres a couple yards around here but i just havent been due to the weather, and ive got to get a new slave cylinder (thats pretty much gonna do me in on funds for a while) how do you take a slave cylinder off the metal line?

  18. #38
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    and yea i found a distributor took alot of looking but a guy that my dad works with had one

  19. #39
    Cajun Road Warrior dualtbi88's Avatar
    Join Date
    Oct 2006
    Location
    Patterson,LA
    Age
    42
    Posts
    593

    Re: 4.3 to 350 swap

    There should be a tiny metal pin holding the line in place. If it's the kind I think it is. Push out the pin and the line should pull out.
    Paul R
    88 Step Side Modified ZZ4 Offenhauser Cross Ram dual TBI, Crane roller cam, FJO injector driver. Hand built serpentine drive.
    still under construction

  20. #40
    Registered User
    Join Date
    Dec 2010
    Location
    ky
    Posts
    39

    Re: 4.3 to 350 swap

    alright thanks hopefully ill be driving it by saturday the damper pulley on a 78 motor wouldnt have been pressed on would it, ive tried both sae and metric bols but a 14mm bolt is too small and a 15 too big , same way with a 9/16 and 5/8

 

 
Page 2 of 3 FirstFirst 123 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •