66 to 71 engine swap (200 to a 250)

Help, I'm looking to see how much work it would be to install a 71 250 6 cyl. engine into my 66 coupe. It will come with c4 tranny still connected along with motor mounts and radiator. I heard the 250 is too tall for the 66 engine bay with hood clearance. I just want to get the car on the road this spring and my 66 200 6 cyl. and tranny will both need rebuilt. Any and all help will be appreciated.
Thanks! Bryan Denis

A 250 can be fitted it just requires some work on the engine mounts to lower it some or if you can find the right factory ones. The Falcon Six Performance Handbook is a good sorce for this info on those parts, you can find that book at severial places one is Vintage Inlines. Good luck on your swap

This spring is a tall order. Cheap rebuild, ie: valve job/rering on the 200 and keep the 250 and plan for a build next winter.

The 250 is several inches wider at the mount bosses than the 200. This width causes the engine to sit higher, then add the fact the 250 block is taller (9.469" vs. 7.808") and hood clearance becomes a problem.

You can lower the 250 engine by slotting the holes in the engine mounts, or install 250 frame mounts from a 69-70 Mustang (if you can find them). Make sure the 69-70 frame mounts are for a 250, not a 200 (which was also available in these years) because the different frame mounts take in consideration the block widths. The mounts come up for sale every now and then on eBay. Also find a low profile air cleaner, the stock 250 air cleaner from a Maverick will work.

I wish I knew what problems there were installing a 250 in my 65 Mustang back in 1977. I didn't know about slotting the engine mounts and had to "massage" the Maverick air cleaner with a BFH to get sufficient hood clearance. I also had to have a machine shop replace the front yoke on the 200 driveshaft with the 250 3-speed front driveshaft yoke. Do you already have a C4 behind the 200 in your 66? I don't know if there are any major differences between the 200 and 250 C4 transmission yokes; you may be able to use your original driveshaft and front slip yoke with the 250 C4.

The 250 swap made a world of difference in my 65. I didn't have any problem using the 7.25 rear axle behind the 250.

Good luck with the swap. Keep us informed.

W E L C O M E to this forum and the whole site !!!

"...66 coupe..."
stang? Each can B different but
most models have the '60s/'70s ford's "low hood issues". There R may B 6 or 7 work-arounds
that many of us have accumulated in responce to these problems. One or 2 mentioned above.
8)
Congrats on the purchase!
It avoids all the pre 1968 issues in the SCV/LOM feedback system. As may B posted above - more info on all this at
"the Handbook". Order one 2: 1) get up to speed/understand just what's up w/these a-lill-different-from the -ordanry-motors; 2) a 'staged build' process that allows U 2 drive while modin & savin 4 the costs involved; 3) ck out carb choices; 3) C a method to do this swap in several ford models; & much, much more. I think it has budget considerations and choices on DYI or contracting out (machine shop etc). Order frm Vintige Inlines if U want - another source for these 'falcon' or ThriftPower engines' parts.
While waiting 4 delivery peruse the "Tech Archive" at above crossed screw driver wrench icon. Then you'll have some more specific Qs that we would be pleased to chim-in on
Where R U?
What will be done 'in-house' (by U) or contracted out?
Again, which model?
What is the specific end goal U seek w/this vehicle (driving conditions? typical uses? 80% of RPM range, etc).

Thanks all! So far the guy is going to give me the motor mounts and the radiator from the 71 250 stang. Should I try to get the frame mounts to put on my car(not sure if the 71 will work, someone mentioned using them from a 69-70 car. The transmission is still attached to the back of the motor, apparently it the same bell housing as the v8 engines of the time. I know I wont be horsing the motor, I just want to drive it down the road, for now, but I figure I will improve it once on the road. Does anyone have a pic of what is meant by lowering the bolt holes on the motor mounts? Once again, thanks all! It's been a long time since I have messed with one of these old cars!

"...lowering the bolt holes..."
'egg out', slot, etc.
to use a die grinder or other means of enlongating the spherical hole into a longer slot (thus 'lowering' the mount/tower/motor, etc. and raising the bolt/frame of the vehicle thus raising the hood).
Also start w/a 'later Maverick' tower (& mount) ie '77.
Now U have 2 or 3 of the ~ 6 methods...
U may not need to do any of this, search out the threads thru use of the search function here to become more informed.