EFI to carb swap - Off-Road Forums & Discussion Groups
Ford 67-96 F-Series, 78-96 Bronco All discussions of 67-96 F-Series Trucks and 78-96 Broncos

 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 05-15-2003, 06:25 PM
**DONOTDELETE**
Guest
 
Posts: n/a
EFI to carb swap

Alright, did a little searching and really couldnt find a definitive answer about what is necessary to switch from efi to carb. I have a 90 bronco with a 302 and 200,000+ thats never been rebuilt. I've decided to swap in a 351w with a c6, but am still not positive which combination would be better for mild performance. I'll probably upgrade pistons, heads, mild cam, and intake. I know the speed density that is on the 302 right now doesnt adjust well to changes. So, would the 351w with a mass air or carb be the better choice? Any opinions are appreciated. Thanks.
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 05-15-2003, 10:42 PM
 
Join Date: Dec 2001
Posts: 4,011
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: EFI to carb swap

Fuel Injection is always better than a carb. Especially on a wheelin' rig.
BigNorm is offline  
post #3 of (permalink) Old 05-15-2003, 10:49 PM
 
Join Date: Oct 2001
Posts: 2,508
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: EFI to carb swap

I agree with BigNorm. If you had a carb and wanted to go FI, I think that is the more complicated way. I would look toward doing the mass air. I do know that it is not a cheap way to go either. But I'll take the FI over carb any day, especially if you are already equipped. Try to keep it simple.
TheJuice is offline  
Sponsored Links
Advertisement
 
post #4 of (permalink) Old 05-16-2003, 12:12 PM
 
Join Date: Jan 2003
Posts: 518
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: EFI to carb swap

Carbs suck when wheeling. They ussually spill too much fuel at extreme angles and flood the moter killing it or killing power because it's running way rich.

My 2 cents: Stroke the 302 to a 347 keep the speed density, try it. If it does not work well change to MAS. Pricey and can be found through JEGS or Summit. I put a blower on my 302 with Speed density. It ran fine off idle, but I couldn't get the idle I wanted. I did end up doing the conversion too mas. The kit came with a 50mm meter bore and I went larger to 70mm and 30 lb injectors. Now I got the thing to idle well, but noticed very little performance change off idle. Something like $1200 later, I don't think I would have converted it knowing what I do now. I should have researched/tried an aftermarket map sensor that may solve any speed density problems you have. I don't know if it would work. You can also squeeze more out of your injectors by adding another fuel regulator. Just some ideas.
I am running a mild cam. I've heard if you go too radical Speed density won't handle the change. Competition cams has a speed density camshaft that is supposed to increase perf. without screwing up the speed density. If you get too radical with a cam you lose the low rpm torque you need for towing and wheeling. I know I mad ethat mistake in my 84 with comp cam 268 duration. It spun up to nice rpms but at the loss of low rpm grunt for crawling around. Good for high revs in sand/mud/cinder climbing but not elsewhere.
Blown is offline  
post #5 of (permalink) Old 05-16-2003, 01:49 PM
 
Join Date: Feb 2002
Posts: 372
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: EFI to carb swap

If you stay with SD, you can change the cam as Blown has said. You need to make sure there is enough vacuum with this cam. This is where the idle issue comes in.

You can also get the GT40P heads that cam off of the Exploders. This is a nice upgrade that I have been looking into too....but it's far down the list of things to do. You might want to look at what some of the 'stang guys are doing with their SD motors. Check out some of those forums.

More than likely you'll need a chip for all of the mods too. It seems like the Diablo chip seems to be one of the better ones out there because it works throughout the powerband and not just at WOT like Superchips or others out there.
lookinfurfun is offline  
post #6 of (permalink) Old 05-16-2003, 09:48 PM
 
Join Date: May 2001
Posts: 398
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: EFI to carb swap

To swap to a carb you'd need a low pressure fuel pump,new intake manifold and carb.Plus the tranny linkage for an aod(if thats what you have).Throw in a duraspark ignition set up too.Not cheap unless you raid the parts off a donor vehicle.EFI is better for wheeling and gas mileage.However it does'nt take a rocket scientist to re jet a carb or set float levels etc.Tuning a computer (especially SD) hopped up motor can be a major pita,it takes bucks(mass air, computer tune etc) to get it right.Pick your poison.For an offroad vehicle I'd stick with efi and make mild mods.If you want major HP swap to carb and let er rip.


CB

broncobilly69 is offline  
post #7 of (permalink) Old 05-17-2003, 01:25 AM
 
Join Date: Dec 2001
Posts: 4,011
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: EFI to carb swap

I'm missin' out on some lingo here. What is SD? [img]images/graemlins/crazy.gif[/img]
BigNorm is offline  
post #8 of (permalink) Old 05-17-2003, 11:17 AM
 
Join Date: Feb 2002
Posts: 372
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: EFI to carb swap

SD=Speed Density
lookinfurfun is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Off-Road Forums & Discussion Groups forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
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:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not 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

 
For the best viewing experience please update your browser to Google Chrome