• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

351 Swap

NickC24

Contributor
Jr. Member
Joined
Apr 4, 2017
Messages
171
Basically I am doing complete frame off build and have everything stripped down to the frame. New body is almost done and the other drivetrains parts are getting there. I was looking at engine options and came across a local, reputable shop that has a 351 they are building to sell and will let me customize how I want since they have just started the build. I called them at the perfect time. I looked into just rebuilding mine but the machine shops around me are charging 9k and taking 6 months-2years on builds. I am pretty set on using the explorer front dress, carb, and 4r70w. Im running 4.11 gears with 32" tires. Planning a 1" BL and 2" SL. I have done a lot of research on the explorer front and it seems like the best option. Same with the 4r70w. Im going with the carb for ease of install and I don't like the look of the explorer efi system/air cleaner. Going of a more classic look. It will most likely never see a trail and will be for driving around town and shows.

I have looked a lot on here about using the explorer with a 351 but I haven't found a comprehensive list of issues and or parts necessary.

My questions are the following:
-Are there any issues with the 351 and the 4r70w i.e. balance and felxplate, bolt pattern, torque converter and so on.
-Will the explorer front bolt to the 351 if using aftermarket aluminum heads and not running the large efi intake (going with carb) I am going to go saginaw dual return for hydro boost brakes with the brackets from WH to run the AC as well
-Any hood fitment issues if not running the stock large air cleaner, going carb (I would like to have as little BL as possible)
-Any oil pan issues (I have read that they are a bit different). If so which one would you recommend.
-What heads and carb setup would you use/recommend
-balance and crank pulley which ones

I know its a lot but I figured I would give it shot. Any information would be much appreciated.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
35,628
351 will work just fine with 4R70W. You do need the right flexplate. It is a standard part, no big deal. Just not the flexplate that comes with the transmission

Explorer front drive will work, but this does require a little modification. The balance factor in the damper is wrong. You need to get it rebalanced from the late 5.0 balance to the early 351 balance.

Hood clearance is a maybe. A 351 can fit under a stock hood if the right parts are used. The high rise performance intake isn't the right part.

There are several oil pan options. Stock 80's truck pan (rear sump) needs clearancing. There is the dual sump crown vic pan, forget the details on that one besides it has the 2 drain plugs. And there is a Bronco specific aftermarket one that has a nipped corner for diff clearance.
 

sanndmann3

Contributor
Bronco Guru
Joined
Jun 13, 2007
Messages
1,790
send the harmonic to DamperDudes for rebalance to 28 oz-in or just buy one of theirs... Explorer crank pulley/harmonic is one piece and has unique offset. Alternative is to buy WH crank pulley and use your harmonic.
Assuming its a 351W and not 351C, all the pieces will bolt up perfectly...
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
35,628
send the harmonic to DamperDudes for rebalance to 28 oz-in or just buy one of theirs... Explorer crank pulley/harmonic is one piece and has unique offset. Alternative is to buy WH crank pulley and use your harmonic.
Assuming its a 351W and not 351C, all the pieces will bolt up perfectly...
The WH crank pulley requires you already have a good 3-bolt damper to reuse. Won't work with a 4-bolt damper. How old is the rubber in your old damper? Probably best to just get the newer one. My vintage damper decided to delete the bond holding the rubber to the iron. Caught it just before the outer ring deleted itself.
 
OP
OP
N

NickC24

Contributor
Jr. Member
Joined
Apr 4, 2017
Messages
171
351 will work just fine with 4R70W. You do need the right flexplate. It is a standard part, no big deal. Just not the flexplate that comes with the transmission

Explorer front drive will work, but this does require a little modification. The balance factor in the damper is wrong. You need to get it rebalanced from the late 5.0 balance to the early 351 balance.

Hood clearance is a maybe. A 351 can fit under a stock hood if the right parts are used. The high rise performance intake isn't the right part.

There are several oil pan options. Stock 80's truck pan (rear sump) needs clearancing. There is the dual sump crown vic pan, forget the details on that one besides it has the 2 drain plugs. And there is a Bronco specific aftermarket one that has a nipped corner for diff clearance.
Thanks for the info. If I’m using after market intake for a carb I’m thinking I should be good with a 1” BL correct. Is there a carb setup that works best for 351 and has low clearance.
 

rocknhorse76

Contributor
Bronco owner since 1993 💪🏻
Joined
Jun 7, 2014
Messages
443
Loc.
Central WA
Damper Dudes 28oz harmonic balancer, flex plate for C4/302, US Shift Quick 2 or 4 transmission controller with a throttle position sensor for your carburetor, and wiring mods for the 4G alternator.
 
Top