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engine swap for 302 -- 6 or 4 cyl-OD

  • Thread starter Thread starter straight deuce
  • Start date Start date Oct 21, 2008
S

straight deuce

New Member
Oct 21, 2008
1
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0
Oct 21, 2008
#1
  • Oct 21, 2008
  • #1
Have removed 302 and c3 trans(both need rebuild) from my mustang II. Looking to replace with a 4 or straight 6 perhaps (from 64 falcon); preferably an OD transmission. I've seen a '76 that had a v6 and the guy had it replaced with a straight 6 from a bronco II/ ranger. Some modifications were made; I don't remember what.

Has anyone here done a similar swap, and/or what could I make (for a motor and trans combo) fit in there without modifying the V-8 driveshaft? Any info would be greatly appreciated.
 

Vegas Stang

New Member
Feb 27, 2008
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Oct 22, 2008
#2
  • Oct 22, 2008
  • #2
WHY?
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Oct 22, 2008
#3
  • Oct 22, 2008
  • #3
Vegas Stang said:
WHY?
Click to expand...

Isn't that a question.

My guess is he is looking for mileage, all needed for that are tires that fit comfortably in the wheelwells, 2.79 gears and a set of heads and pistons that make a little better compression than stock. That should get the car into the 20s.

And about hte OP:

I don't think it was a C3 transmission removed.

And

I don't think a straight 6 could fit inside the engine compartment without a SawZall.
 

Steel Steeds

New Member
Aug 31, 2005
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Portland, OR
Oct 22, 2008
#4
  • Oct 22, 2008
  • #4
Wart said:
I don't think it was a C3 transmission removed.

And

I don't think a straight 6 could fit inside the engine compartment without a SawZall.
Click to expand...

Right-O. Rangers/Bronco IIs never had a straight six option, those were V-6 engines that were optional. They'll fit.
 

78CobraII

Moderator
Jul 31, 1998
1,808
8
39
Birmingham, AL
Nov 11, 2008
#5
  • Nov 11, 2008
  • #5
I have a pic of a straight 6 in a II archived somewhere...I'll try to dig it out. It was really tight, but even so I suspect that it was a 200 rather than a 250. It was not an attractive swap.

For any engine or transmission swap, plan on modifying the driveshaft. Its rare not to have to.

In many cases, a smaller engine does not necessarily get you better gas mileage because you have to work the smaller engine so much harder.

If the need for fuel mileage is not extreme, then a mild 302 with a T-5 and 3.00 rear gear would get pretty good gas mileage. Usually a properly tuned small 4-bbl carb will get better gas mileage than a big 2-bbl (as long as you keep your foot out of the carb!) because the front barrels are smaller than those of the 2-bbl...unless of course you are using the progressive 2-bbl Weber carb found on the MII 2.3 and 2.8 engines.

Hmmm...how about a pair of the 2-bbl Webers on a dual carb manifold? If you tuned them right you would run on the smaller primary barrels most of the time...
 
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