New here, swapping vortec into 86 ss

Status
Not open for further replies.

Mrchillwill

Not-quite-so-new-guy
Jan 25, 2019
10
2
3
New here, and i was wondering if i can still use my original wire harness and computer with the vortec engine from 98 chevy truck, i will be swapping it to carb, since it has the hole for the mechanical fuel pump and push rod, any help will be much appreciated

Swapping into a 86 monte carlo ss
 

Gwarren79

G-Body Guru
Oct 29, 2018
711
1,547
93
Safford, AZ
Mechanical fuel pump not drilled correctly. It is cast, but not machined. You have to disassemble the engine, and have it drilled larger, then honed to spec.
 

Mrchillwill

Not-quite-so-new-guy
Jan 25, 2019
10
2
3
Mechanical fuel pump not drilled correctly. It is cast, but not machined. You have to disassemble the engine, and have it drilled larger, then honed to spec.
Are you sure because i have it monted on engine and it seems fine, its a 305 vortec, i should have clarified the engine
 
Oct 14, 2008
8,806
7,746
113
Melville,Saskatchewan
That is a rare engine, the 305 weren't nearly as common. You need a spreadbore intake manifold for a Vortec motor. I believe they were made for marine and industrial motors, Rktpwrd on here is using one. If you can find one, it should work fine. What accessories are you planning on using? Good luck.
 
  • Like
Reactions: 1 user

Yav8

Master Mechanic
Aug 19, 2014
275
114
43
Manitowoc wis.
I have done a lot of these vortec motors that are set up for a fuel pump. All will come with a plate to cover the machine holes and will have a slug of oil when you take the plate off. IF you have one that is not drilled but had the holes started all you need to do is get a 1/2 long drill and finish the last 1/8 inch of cast iron. You will also need to drill the small hole for the oil to drain back. If your motor has not been started or machined in any way JUST get a electric fuel pump and intall it. The intake you will need are the ones for the vortec bolt pattern. New or used $80-$150. The 305 is a good start but you could alway upgrade to a 350 and reuse the parts you have for the 305. Maybe at a later date.
 
  • Like
Reactions: 2 users

Mrchillwill

Not-quite-so-new-guy
Jan 25, 2019
10
2
3
Thank you very much for the help. I already have intake and carb, so are you saying it will be easier to put a electric pump, also would it be inline or in the tank? I will upgrade later but i got the engine for free and its running 😁

Intake and carb and dist. Are from summit,
I have done a lot of these vortec motors that are set up for a fuel pump. All will come with a plate to cover the machine holes and will have a slug of oil when you take the plate off. IF you have one that is not drilled but had the holes started all you need to do is get a 1/2 long drill and finish the last 1/8 inch of cast iron. You will also need to drill the small hole for the oil to drain back. If your motor has not been started or machined in any way JUST get a electric fuel pump and intall it. The intake you will need are the ones for the vortec bolt pattern. New or used $80-$150. The 305 is a good start but you could alway upgrade to a 350 and reuse the parts you have for the 305. Maybe at a later date.
Thank you very much for the help. I already have intake and carb, so are you saying it will be easier to put a electric pump, also would it be inline or in the tank? I will upgrade later but i got the engine for free and its running 😁

Intake and carb and dist. Are from summit,
 

Mrchillwill

Not-quite-so-new-guy
Jan 25, 2019
10
2
3
That is a rare engine, the 305 weren't nearly as common. You need a spreadbore intake manifold for a Vortec motor. I believe they were made for marine and industrial motors, Rktpwrd on here is using one. If you can find one, it should work fine. What accessories are you planning on using? Good luck.
Engine came from a gmc, dont know what parts yet besides intake and carb
 

Yav8

Master Mechanic
Aug 19, 2014
275
114
43
Manitowoc wis.
Its going to be a roller cam motor. Heads have the ramp in the intake side not like the 350 heads 906 or the 062s. Keep it together and put the intake and dist on the motor and have fun. As for the fuel pump just get a inline and splice it into your fuel line and hook up the hot wire and ground the other. It a lot of work to drop a fuel tank just install a intank pump. A simple inline should cost under $40-$50 and be sure its for a carb application not a fuel injected one.
 
  • Like
Reactions: 1 users
Oct 14, 2008
8,806
7,746
113
Melville,Saskatchewan
Interesting conflicting info on these heads. Looks like a L98 chamber 1.84" intake valve and similar ports to the 350 Vortec heads. It is rated at 230 hp so I would bet the above info is right.
 
Last edited:
Status
Not open for further replies.

GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.

Please support GBodyForum Sponsors

Classic Truck Consoles Dixie Restoration Depot UMI Performance

Contact [email protected] for info on becoming a sponsor