‘97 4.3 2bbl to 4bbl conversion?

[jkimball]

I have a ‘97 4.3 with 2bbl that floods and is needing rebuilding, also have some corrosion on the manifold. So, I figure if I have to consider replacing the manifold anyhow why not go 4bbl.
National Carburetor will build me an Edelbrock 500 cfm for $275 and I plan to use the Edelbrock 2519 (marine) intake.

my question is, other than re-bending fuel line to route to the new location, is the 4bbl throttle bracket the only other item needed for install? Maybe a PSI regulator to keep the carby happy at 6> psi

also, since pulling distributor and reinstalling - I assume I may need to throw a timing light on it?

thanks for the help

 

[Bondo]

Ayuh,...... Just use the 1409 carb right outa the box, 'n it matches the Merc/ Weber carb, Merc fuel line, 'n throttle bracket,.....

 

[jkimball]

Thanks Bondo - I thought about the 1409 but Natl. offered the 500 build so cheap it seemed like the ticket. This makes me rethink it if I don’t have to mess with the fuel line.
what about re-jetting it? Is that necessary with the vortec heads? I’ve heard both ways so seems the jury is out?
Should I still run a PSI regulator or is the fuel psi ok for the 1409?
And lastly, going from the 2bbl and that throttle bracket - do I not need the OEM 4bbl bracket? (805359T -see pic)?

iI just want to do it right and as reliably as possible.

 

[Scott Danforth]

Open the box with the 1409, bolt on the motor and go boating...... Its already calibrated for a 4.3 vortec

 

[Scott06]

Thanks Bondo - I thought about the 1409 but Natl. offered the 500 build so cheap it seemed like the ticket. This makes me rethink it if I don’t have to mess with the fuel line.
what about re-jetting it? Is that necessary with the vortec heads? I’ve heard both ways so seems the jury is out?
Should I still run a PSI regulator or is the fuel psi ok for the 1409?
And lastly, going from the 2bbl and that throttle bracket - do I not need the OEM 4bbl bracket? (805359T -see pic)?

iI just want to do it right and as reliably as possible.

either edlebrock option you may have to redo the fuel line if your original comes in on the left side of carb as you face it it may bolt up.

yes that is the correct throttle bracket

There are a few threads on tuning the edlebrock for a 4.3 on here you can look up or google it.

 

[jkimball]

either edlebrock option you may have to redo the fuel line if your original comes in on the left side of carb as you face it it may bolt up.

yes that is the correct throttle bracket

There are a few threads on tuning the edlebrock for a 4.3 on here you can look up or google it.

Thanks!
I’ve been googling and googling... I feel like I have found the end of the Internet. It’s hard to find a solid answer, seems equally divided though that 1/2 says it’s ready out of the box for Vortec, 1/2 say use the 1485 kit and only one post I found said that he had to mix and match parts to get his right.

 

[Scott06]

https://forums.iboats.com/forum/eng...ves/10154544-stumbling-edelbrock-1409-4-3l-v6