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440 heads on 383 block...?
hi! a few dodge questions for someone who has done this or has knowledge of both:
will '77 model 440 heads fit and work on a 70's model 383 block...
will the 440 heads increase or decrease compression...
if increase, any guess how much...
will pushrod length change...
will i need special head gaskets or will the 383/440 gaskets work...
if they will fit, do i use a 383 or 440 intake...
my 440 bottom is bad, i had the heads redone before i knew about the bottom end. i found someone who has had the bottom end of a 383 rebuilt for sale for $400 and was gonna buy that, put these heads on that block and the assembly would go in a class A motorhome, this is why i'm asking.
thank you.
6 Answers
- 1 decade agoFavorite Answer
The '77 heads will fit on the 383 block.
Compression will depend on the amount of metal removed from the 440 heads and the original compression ratio of the '70's 383 (383 only manufactured in 1970 and 1971, became a 400 in 1972).
Use push rods and intake from the 383 engine.
Head gaskets are interchangeable, but I'm pretty sure the motorhome heads had a larger coolant port than the auto engine, make sure the new head gaskets match the coolant port size on your 440 heads.
Having said all that, purchase a remanufactured 440 short block and install your good heads, the longer stroke of the 440 gives you the needed torque for a motor home. I think the 383 engines are great, but your application calls for a 440.
Source(s): Forty five years of shadetree engineering, racing, and home auto repair, all Mopars, mostly Dodges. - Anonymous1 decade ago
The heads are essentially the same. There may be some difference in the final compression and you will want to use all the 383 parts. But I really think you should bite the bullet and get a 440 or larger as that motorhome really needs the big engine. If that 383 is not a truck engine it will not pull as well and will probably be very hard on fuel. I want to tell you that they began making 383s in 1959 but I may be one year wrong, not that it matters.
- Nigel MLv 61 decade ago
they will fit - BUT; the 440 is a RB engine, the 383 is a B
http://en.wikipedia.org/wiki/Chrysler_RB_engine
http://en.wikipedia.org/wiki/Chrysler_B_engine
The R in RB means raised deck, which means that the heads are further apart on the RB than on the B - meaning everything between the cylinder heads is different - except the gaskets. The push rods are roughly an inch shorter on the B than the RB, exhaust manifolds end up moved an inch or so too. intake goes with the block.
Compression may be lower than it was in your 440, it will be much lower than an early 70s 383.
I would have your 440 block redone. The 383 is going to have 15% less torque - which you will notice, and the torque peak will be at a higher rpm - which you may notice even more.
- 5 years ago
The 440 and 426 are both RB (raised block) engines and almost identical externally but the heads are not the same. The 383 is a B block engine.
