I want to drop a crate 440/425hp engine into the 318 base Challenger.
Any requirements, recommendations and suggestions in regard
upgrades to transmission, rear end, brakes, suspension, cooling, exhaust etc ?

thanks

Make a list of what is under the car now and we may be able to make some suggestions. You do know that just about anything that connects to the small block will need to be changed for the big block, don't you?

Its a stock 318 challenger -
I don't believe the k-frame needs to change?

I know for sure need to change the auto transmission to 727,
drive shaft, rear end axle and differential.

ADD sway bars front and rear, HD brakes and
HD torsion bars.

I think you need to find out what you have before you start ordering parts.

My 73 Challenger had a 318 and came with an 8 3/4 rear axle. No need to change that out. If you currently have a 727 you can keep the driveshaft.

Sway bars aren't required, per se but you may already have a front one.

What brakes do you currently have?

You could easily get that horsepower from a stroked small block and save a bunch of money with much less BS.

Gus

yeah i second that. you can run the 318 and get 425 hp. whats the plans for the car? driver? street/strip? a 425 hp 440cuin engine is basically a stock rebuild with some aftermarket heads.

Lot of difference between a small block and big block handling.

K Frame is the same. All V8's except the Hemi had the same basic Kframe.
Motor Mount isolators are the same, (Rubber part)
Motor Mount Brackets (Metal bracket on engine to Rubber isolator) are different.
Transmission mount and isolator are the same.

1970 floor shift cars had a shift interlock linkage. It is not needed if you lock the shift tube in the column and it is a floor shift car. If you keep it, then it will be different big block to small block and 904 to 727

If the transmission is already a 727 floor shift then New transmission and kickdown linkage are needed but all else is the same.

If the transmission is a floor shift 904 then:
The bracket that holds the lower part of the shifter bellcrank is different,
The kickdown linkage is different
Probably the Rod to the shift lever.
Driveshaft and slip yoke are different too.
Of course you need the 727 Transmission.

Column shift cars need the correct bracket for the shift linkage for the Big Block. Nearly all linkage if swapping from 904 to 727. I doubt it is column shift. Not many column shift Challengers.

Rear end is OK if it is and 8-3/4, Gear change is optional.

Sway bar is a nice plus. Can be left off but really worth it in my opinion.

Torsion bars will need to be replaced and if you drive hard the rear springs will probably need to be looked at.

Exhaust is different and you would want duals instead of single anyway.

Engine wiring is slightly different. A new engine harness or modify the old one.

Power steering brackets and probably hoses.

If you have/want AC the brackets and hoses are different.

Radiator, fan shroud and hoses need replaced if it is still stock.

Not a hard job except finding or paying for the linkage.

Me, I'd go with a stroked LA unless I absolutely needed 440 CI.
Did that on a Duster street car, and loved it.

I agree. A 408 with the right cam and good heads would be a lot shorter route and the car will drive better with the lighter power plant. If it's got a 904, stay with it. Just beef it some.

He said he has a 1970 with a 318. That should have the small rear end. He will need an 8&3/4 rear behind the 440. All E bodies 1972 and up came with the 8&3/4 rear but not in 1970. I like the idea of the stroked LA motor. E bodies ride and handle better with small blocks.

I can't knock small blocks but putting your foot in a big block will put a smile on you face. I did this swap but with a 383. Definitely get the lager torsion bars, I was lucky and found a set in a junk yard.

Appreciate the idea and suggestions to stroke the 318...

This is what I have:
1970 Challenger 318, floor shift 904 and 7 1/4 rear end.
and a Crate 440
To summarize needs: Appreciate info where I can purchase these items:
- Motor mounts and brackets
- The bracket that holds shifter bell crank -
- Kick down linkage for 727
- Rod to shift lever
- Drive shaft and slip yoke
- 727 Transmission
- 8 3/4 rear end
- sway bars -front and rear
- torsion bars
- dual exhaust
- power steering brackets/hoses
- Radiator and hoses.

pics

You have a big (and expensive) job ahead of you there. It might be a challenge finding everything you need for it right now. You have the large radiator opening, that is a good start. I do have a couple of questions up front;

Do you plan to keep the A/C with the 440? Do you have the standard flat hood? And then, is there a time or money budget on this project?

I will make a couple of suggestions on the shift linkage; lock out the shift interlock rather than mess with redoing it. Just make up a one piece kick down like the later models had. I usually make my own from Dodge trucks in the pick-a-part yards. The key is getting the right ratio between the carb arm and the arm on the tranny. Make sure that the 727 you get has the mount on the tail shaft for the shift rod arm. You see the arms at the Mopar swap meets regularly and they are in repop, too. Is the 904 arm different than the 727 arm? Year One shows them all on back-order and only lists a 727 arm.

Have the flat hood - intend to go with AMD shaker and a shaker kit 4bbl.
Have A/C Intend to remove A/C.
Have 7 1/4 intend to get a Mopar Madness 8 3/4 complete brakes

I'm committed to the project - time not an issue - money is always a concern.
Before starting I like to have all the components on hand already have the car and the crate engine.

What parts in your mind are gonna be an issue/challenge to get?
Here is a list thus far...
Motor mounts and brackets
- The bracket that holds shifter bell crank -
- Kick down linkage for 727
- Rod to shift lever
- Drive shaft and slip yoke
- 727 Transmission
- 8 3/4 rear end
- sway bars -front and rear
- torsion bars
- dual exhaust
- power steering brackets/hoses
- Radiator and hoses.
- HD leaf springs

Save yourself a LOT of time, money and effort, sell this car unmolested and buy an already built 440 Challenger. 2¢

Do you want it to look stock or is aftermarket ok?

Lots of options open up if you go aftermarket. Radiators, exhaust, kiickdown, swaybars, etc are available aftermarket and can be a better option sometimes. Also if you want original then you will be looking for early 70's 440 parts but non original opens options on brackets, pulleys etc from different years that may be more easily available.

Aftermarket parts are fine.- availability is more important.