440 into 70 challenger

[steveschwenke]

Hello everyone
I have 70 challenger that had a 318 in it and i have the chance to either put in a 340 or a 440
what is entaled and needed and approx cost in the 440 conversion because this is the route i would rather take
Thx steve

 

[R/T4speedconv]

While a 440 is sexy the E-body is at its best with a 340 sixpack in it as far as handling the corners and aint bad at "go". I have a 440 but it is at its best straight ahead. The E-body with a small block is a better over all, In my opinion. (let the flaming begin ) If I ever get a second Challenger I will go for the small block myself and enjoy the better front/rear balance.
The 440 will bolt up to the K member, you will need the heavier torsion bars and springs. Bigger brakes. Manual or auto tranny? But then again you will for the 340 too. Price wise I will guess it will not be much difference between the 440/340 in the long run. It is a bit of a squeeze to get to the plugs on the 440 and much easier on the 340.

 

[Cranky]

A small block will be an easier swap since the under hood wiring is the same and you can probably use the same radiator but sticking in a big block isn't hard. Since the distributor is up front on a BB, you'll have to address the wiring for that etc. You might can use the same radiator depending on your water pump housing suction location. You will need a big block trans (727), drive shaft will be shorter if the teen came with a 904. What rear do you have. Small block K frame will take the BB with the right motor mount brackets. What's your plan for the car? Street, street/strip, cornering? If drag racing is in your plans, you can use the 318 bars....like R/T4 says, plugs are a bit tighter to get to but you can even get to them from the bottom.....

 

[steveschwenke]

A small block will be an easier swap since the under hood wiring is the same and you can probably use the same radiator but sticking in a big block isn't hard. Since the distributor is up front on a BB, you'll have to address the wiring for that etc. You might can use the same radiator depending on your water pump housing suction location. You will need a big block trans (727), drive shaft will be shorter if the teen came with a 904. What rear do you have. Small block K frame will take the BB with the right motor mount brackets. What's your plan for the car? Street, street/strip, cornering? If drag racing is in your plans, you can use the 318 bars....like R/T4 says, plugs are a bit tighter to get to but you can even get to them from the bottom.....

I have the tranny and mostly looking for steet and some strip

 

[Chryco Psycho]

you will need a different trans or belhousing as the bolt patttern is different between the 2 , I would recommend 1" torsion bars , the rad needs to be bigger & you need all the associated hardware for the big block such as mounts alt brakets , power steering brakets . Wiring is simple eonough , 4-5 wires need to be extended to reach the front of the engine,
Simple swap really

 

[71383bee]

Hands down the 340 is the better way to go. It will drop right in and need almost nothing. The 440 will need as mentioned a whole laundry list of items. Besides the 340's lighter weight will make the car handle better and getting 400+ from a 340 is very easy to do.

As for plug changes. big blocks are a complete PITA compared to a small block.

I guess I am a bit biased, but I really like 340's and its fun to against the grain.