My neighbor has a 74 Mustang with a V6 that is seized up. I know a V8 conversion won't be that difficult, but I would like to know some specifics about whats compatible with the V8 from the V6. Does the bell housing interchange? I'm guessing no. It's an auto trans, will it need a new torq converter? I'm sure motor mounts will have to be changed. Anything else you can help me with would be greatly appreciated.
1974 Mustang V6 to V8 conversion
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A v8 conversion on a '74 is more involved then with the other years because the 1974 was not designed for a v8. You will need to find motor mounts, bell housing, radiator, and other odd and ends parts. You will also have to cut the radiator support out and secure your hood with hood pins. Also you will need to get a v8 front suspension and beef up the sub frame connectors or as other members will vouch for, your car will quite literally rip in half. The v8 is to heavy for the '74 sub frame. Now with all that it is not impossible in fact it is very doable, it is just more involved then the other years. My suggestion is to fit another 2.8 under the hood and look into beefing that up. I have a '74 and if you do your research, the 74 had 105 hp, the next year 75 the 302 only had 135 hp, so to get to that generation 302 power would not take much with a 74 v6. If you use a later 70's motor you might want to keep the heads off the 74 as they were non smog heads and they flow a little better. But that is my 2 cents. Feel free to correct any information i might have wrong (pain meds my back is out):shiny:
No they did come with a 8 inch rear end though. I think the 2 options in the mustang 2 was the 6.25 and 8 inch rearends with a variety of gear ratios. When you look under the back side of the car, if you can see bolts on the pumpkin then it is a 6.25, if you don't see bolts then it is an 8 inch rear end (obviously this is the better choice
) as for the choice on rebuilding the engine, if you do your research the 2.8 cologne was a very popular 6 for racing in europe. You can find some parts here in the US such as the offy 4 barrel intake and headers you just have tp dig a lil. The six is just a little more challenging to build but just think put enough in it, and watch the v8 guys mouth drop at your growling v6 passing them up:gringreen. offy intake $400, headers $300, the look on the guys face in the camaro you just passed priceless.
) as for the choice on rebuilding the engine, if you do your research the 2.8 cologne was a very popular 6 for racing in europe. You can find some parts here in the US such as the offy 4 barrel intake and headers you just have tp dig a lil. The six is just a little more challenging to build but just think put enough in it, and watch the v8 guys mouth drop at your growling v6 passing them up:gringreen. offy intake $400, headers $300, the look on the guys face in the camaro you just passed priceless.
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engine swap
ok,i have done the 1974 swap...my car originally had the 2.3 four banger with 4 speed manual,i took it out and stuck in a 289 hi-po with automatic tranny. This is what i had to do...first you will need to find motor mounts...they are not easy to come by...then you will need to locate a fan spacer that is only 1 inch or less in length(I had to have one machined.) The wireing harness from a v-8 mustangII will work,but you will have to modify a couple of the plugs...ie for some reason you will need to lengthen the wires going to the altenater.
next...you have to take your hood latch off of your hood,and actually cut the hole bigger so your radiator cap will fit inside of it,when its closed...then you will have to cut the top of the radiator mount off the car,this includes takeing off the hood latch,and you will need to remave the air conditioner condenser from its place in front of the radiator,also remove the power steering cooler and splice your power steering lines back together without it.
now you will have to locate a square radiator out of an older model ford car or truck...late 50's or 60's,as the original rectanguler radiator will not work...make sure if you plan on useing an auto transmission,that it has coolant ports for the transmission coolant lines...the radiator must be removed from the car,andthe new one placed in front of the old radiator mount,directly behind the grill...a few other odds and ends will probably have to be removed from there...ie...the horn,and so forth. you will have to drill new holes to mount the radiator with,next you will have to find a long universal flex coolant hose to use on the bottom of the radiator.
a fan shroud must be used,and you will have to make one...i used some old tin i had laying around...DO NOT USE A FLEX FAN FOR YOUR FAN...you will not have room for a clutch fan,and will probably want to buy a flex fan...dont do this,as the flex fan actually will cause your v-8 to over heat...for some reason it actually will block incomeing air,instead of bringing air in...you will have to find a solid four or five blade fan,and bolt it direct.
the transmission coolant lines are a bear to get in,as the tranny is a tight fit,if you go with an automatic...the 74 mustangII wasnt made for a v-8 so the lines will have to be routed through your frame rails,and back out and up to the tranny...otherwise they will be to close to the exhaust,and cause the transmission to overheat and burn up(I learned all this the hard way...lol) If you use an automatic transmission the fram crossmember near the rear of the engine compartment will have to be unbolted and removed,and a new one fabricated,preferably out of stonger material,but it will have to hang much lower.
the springs,need to be changed to heavier ones...i did not,and as a result,i only had 1.5 inches of ground clearance...if you like low riders then this is fine.
you will need to install hood pins to keep your hood shut...
now all this being said...i did all this,and the car was fun,but i broke two door hinges and a windsheild,because of frame flexing...also i couldnt keep a transmission as they kept burning up...my little 6.25 rear end handled everything ok...never had a problem with it,but i kept the 13 inch tires,so spinning them was very easy,and traction wasnt hard on the rearend. BUT I HAVE NOW CONVERTED THE CAR BACK TO A 2.8 V6 and it is waaaaaay more fun and driveable!
here is a website for v-6 performance parts for the 2.8ltr (i am new to this so i hope this works...) Ford Ranger/Bronco II 2.8 liter Engines
anyway if it doesnt link then copy and paste it minus the parts. good luck and have fun...MUSTANG II'S ROCK!
ok,i have done the 1974 swap...my car originally had the 2.3 four banger with 4 speed manual,i took it out and stuck in a 289 hi-po with automatic tranny. This is what i had to do...first you will need to find motor mounts...they are not easy to come by...then you will need to locate a fan spacer that is only 1 inch or less in length(I had to have one machined.) The wireing harness from a v-8 mustangII will work,but you will have to modify a couple of the plugs...ie for some reason you will need to lengthen the wires going to the altenater.
next...you have to take your hood latch off of your hood,and actually cut the hole bigger so your radiator cap will fit inside of it,when its closed...then you will have to cut the top of the radiator mount off the car,this includes takeing off the hood latch,and you will need to remave the air conditioner condenser from its place in front of the radiator,also remove the power steering cooler and splice your power steering lines back together without it.
now you will have to locate a square radiator out of an older model ford car or truck...late 50's or 60's,as the original rectanguler radiator will not work...make sure if you plan on useing an auto transmission,that it has coolant ports for the transmission coolant lines...the radiator must be removed from the car,andthe new one placed in front of the old radiator mount,directly behind the grill...a few other odds and ends will probably have to be removed from there...ie...the horn,and so forth. you will have to drill new holes to mount the radiator with,next you will have to find a long universal flex coolant hose to use on the bottom of the radiator.
a fan shroud must be used,and you will have to make one...i used some old tin i had laying around...DO NOT USE A FLEX FAN FOR YOUR FAN...you will not have room for a clutch fan,and will probably want to buy a flex fan...dont do this,as the flex fan actually will cause your v-8 to over heat...for some reason it actually will block incomeing air,instead of bringing air in...you will have to find a solid four or five blade fan,and bolt it direct.
the transmission coolant lines are a bear to get in,as the tranny is a tight fit,if you go with an automatic...the 74 mustangII wasnt made for a v-8 so the lines will have to be routed through your frame rails,and back out and up to the tranny...otherwise they will be to close to the exhaust,and cause the transmission to overheat and burn up(I learned all this the hard way...lol) If you use an automatic transmission the fram crossmember near the rear of the engine compartment will have to be unbolted and removed,and a new one fabricated,preferably out of stonger material,but it will have to hang much lower.
the springs,need to be changed to heavier ones...i did not,and as a result,i only had 1.5 inches of ground clearance...if you like low riders then this is fine.
you will need to install hood pins to keep your hood shut...
now all this being said...i did all this,and the car was fun,but i broke two door hinges and a windsheild,because of frame flexing...also i couldnt keep a transmission as they kept burning up...my little 6.25 rear end handled everything ok...never had a problem with it,but i kept the 13 inch tires,so spinning them was very easy,and traction wasnt hard on the rearend. BUT I HAVE NOW CONVERTED THE CAR BACK TO A 2.8 V6 and it is waaaaaay more fun and driveable!
here is a website for v-6 performance parts for the 2.8ltr (i am new to this so i hope this works...) Ford Ranger/Bronco II 2.8 liter Engines
anyway if it doesnt link then copy and paste it minus the parts. good luck and have fun...MUSTANG II'S ROCK!
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