250 CI Swap into 1970 Bronco

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70Bronco250
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250 CI Swap into 1970 Bronco

Post #1 by 70Bronco250 » Wed Sep 18, 2013 10:17 pm

I doubt this is the first time someone has brought up the swapping of a Ford 250 six cylinder in a 1970 Bronco. So forgive me for bringing up a topic that likely has taken up much discussion time in the past. I would simply like to have a short totorial on a successful swap. Anything that removes easily avoided mistakes would be great. I understand that the 250 is roughly 2 inches taller than the 170 or the 200 and does that require a body lift for hood clearance issues or a hood scoop of some kind? I amconsidering a transmission swap also to get better economy and again a little more fun factor . Recommendations on transmission swaps would be welcome also.


This is a father son project and I am not looking for rocketship performance but rock solid reliability and fun factor for my son and myself. He wants to learn to drive a stick and I can not think of a more fun stick to learn to drive than an early Bronco.

Thank you ahead of time.

Doug

bmbm40
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Location: Carson City, NV

Re: 250 CI Swap into 1970 Bronco

Post #2 by bmbm40 » Thu Sep 19, 2013 9:17 am

Do a 1" body lift. Your rubber body bushings are most likely in need of replacement anyway. I slotted my motor mounts to drop the 250 lower but doubt if it was really needed. I have no hood clearance issues with the stock air cleaner.
I went with the NV3550 which is the best choice in my opinion but if i did it again I would use the M50D as it would probably cost a lot less. The torque characteristics of the 250 are well suited to the bronco along with a trans upgrade it is a great driving experience.
Start gathering parts soon. Let me know if I can help. Also classicbroncos.com has lots of good info.
66 Bronco-1970 250, NV3550, DSII, 4 turn ps, uncut, 1" bl, 2.5" sl, front disc, twin stick D 20, 30 x 9.50
NEXT- direct mount 1.08 on D8 head, power brakes, rear limited slip, 3G, electric fan, electric upgrades, custom curved DSII, header, 31" tires

New guy? Get the Falcon Performance Handbook and Ford six high performance parts from https://vintageinlines.com

bmbm40
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Posts: 1080
Joined: Tue Feb 22, 2005 6:25 pm
Location: Carson City, NV

Re: 250 CI Swap into 1970 Bronco

Post #3 by bmbm40 » Fri Sep 20, 2013 5:15 pm

Also you may want to move this to the Bronco section. Not sure how to do that.

I don't think there are any real pitfalls to this conversion. Mine was done about three years ago but I remember having to fab up some clutch linkage. Also you will need a 300 flywheel and bell which you might get with a junkyard M50D which was used on F 150's. Somewhere on Classic inlines site there is a discussion on 250 swap stuff just have to look around. The oil pan needs a little work and someone on this site or classicbroncos.com came up with a good solution, when I find the link I will send it to you. Good luck.
66 Bronco-1970 250, NV3550, DSII, 4 turn ps, uncut, 1" bl, 2.5" sl, front disc, twin stick D 20, 30 x 9.50
NEXT- direct mount 1.08 on D8 head, power brakes, rear limited slip, 3G, electric fan, electric upgrades, custom curved DSII, header, 31" tires

New guy? Get the Falcon Performance Handbook and Ford six high performance parts from https://vintageinlines.com

bmbm40
Registered User
Posts: 1080
Joined: Tue Feb 22, 2005 6:25 pm
Location: Carson City, NV

Re: 250 CI Swap into 1970 Bronco

Post #4 by bmbm40 » Wed Sep 25, 2013 1:26 pm

It's all coming back to me now.
You might find a 250 flywheel somewhere I happened across one on Ebay but a member on here might have one. Also any sbf bell should work and I seem to remember if you use a 300 bell and flywheel you can use a larger clutch.
If i remember any thing important I will let you know.
66 Bronco-1970 250, NV3550, DSII, 4 turn ps, uncut, 1" bl, 2.5" sl, front disc, twin stick D 20, 30 x 9.50
NEXT- direct mount 1.08 on D8 head, power brakes, rear limited slip, 3G, electric fan, electric upgrades, custom curved DSII, header, 31" tires

New guy? Get the Falcon Performance Handbook and Ford six high performance parts from https://vintageinlines.com

bmbm40
Registered User
Posts: 1080
Joined: Tue Feb 22, 2005 6:25 pm
Location: Carson City, NV

Re: 250 CI Swap into 1970 Bronco

Post #5 by bmbm40 » Fri Oct 11, 2013 10:57 am

See the work jimmyv did on his oil pan. That is the way to go.
66 Bronco-1970 250, NV3550, DSII, 4 turn ps, uncut, 1" bl, 2.5" sl, front disc, twin stick D 20, 30 x 9.50
NEXT- direct mount 1.08 on D8 head, power brakes, rear limited slip, 3G, electric fan, electric upgrades, custom curved DSII, header, 31" tires

New guy? Get the Falcon Performance Handbook and Ford six high performance parts from https://vintageinlines.com

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