Whats the difference fron 2bbl to 4bbl 383?

[javakmcharger68]

I just got a 67 383 & it is a 2bbl engine. What is the differences between the 2 & 4bbl engines. Are the heads the same as a 4bbl or are they made for these engines. I know the intake is different of course, but other than that I know nothing.  Any help you can give would be great. Thanks

[Ghoste]

Lower compression, I THINK, and I say again that this is only a guess, that the cam and heads were the same but the exhaust manifolds were different.

[javakmcharger68]

Thanks ghoste that sounds right to me.

[cudaken]

 Heads should be 516's and where the same on 2 and 4 barrel. Pistion's should be 8.5 to 1, HP was 10.0 to 1. Cam is driffrent and I think the springs as well.

                     Cuda Ken

[Ghoste]

Are you sure about the cam, Ken?  I only see specs for one in the 67 fsm.

[javakmcharger68]

Have some more info off the engine, but can't get those heads to move with nothing holding them down. Any ideas? Tapping is not working & I don't want to put a screw driver between the head & the block. Block is stamped 67 on side but the I.D plate has a D383, so its 68 isn't it? CudaKen, are you saying the valve springs will have to be changed with the cam?

[Ghoste]

If the block is stamped 67, then that's when it was cast.  It should have the full casting date on there.
Stick a prybar into the heat crossover and give it a little lift there.

[cudaken]

 Ghoste I am 95% sure they would be driffrent but would not sware it is. Need to dig out the bible to make suer and right now. Well just happy to sort of see the Keyboard. Belch.

Javakmcharger68, unless the 383 has less than 85,000 miles all most ever thing should be replaced except the head, block crank and the tin. Tin is valve covers, oil pan and chain cover.

A long time ago when I was young and dumb I asked a shop to bulid me a new (well sort of new) 440 but wanted to used the all the old parts like pistons, rocker arm's, shafts, push rods, cam chain well you get the idea. Mack asked me "do you want this to run like a new 440 or a 65,000 440". I got his drift and did not bulid the cheap 440 and sold it.

1967 was 38 years ago, unless it is a low mileage 383 don't be cheap unless you half to be. I have been there as well.

                                   Cuda Ken   

[Chryco Psycho]

you will need new springs to match the cam you will use
Make Sure you have all 17 head bolts out before you pry anything , the 516 heads are good if that is what you have , probably you have 250 or 906 heads though

[Nacho-RT74]

I think difference is one more time the same as Magnum o not engine... beside different pistons to get more compression, also difefrence on cam, both manifolds, springs, AND maybe double or single time chain and sprockets.

[javakmcharger68]

Chryco Psycho takes the prize by saying this statement Sure you have all 17 head bolts out before you pry anything . Has been awhile since taking a BB dodge heads off so I never seen the bolts down bellow because of dirt &  grime. The heads on the 67 block has 906 heads on it, & the block is cracked. 906 heads no good ??  Any guesses on what kind of crank? Thanks

[cudaken]

 Soory to hear the block is cracked. If it has the right crank it should be a steel crank. 906 heads are good, Neil likes the 915's better, Ron likes the 452's better my self I like the 906's heads.

There is a chances someone may have but in a 400 crank at one time. Easy check is look at the blancer, steel crank one will only be about 3/4" wide. Cast one will be about 1.5" wide.

                                       Cuda Ken

[firefighter3931]

I just got a 67 383 & it is a 2bbl engine. What is the differences between the 2 & 4bbl engines. Are the heads the same as a 4bbl or are they made for these engines. I know the intake is different of course, but other than that I know nothing.   Any help you can give would be great. Thanks

The pistons will be lower compression. The intake manifold is obviously different. The cam/valvesprings are also different. Exhaust manifolds are different. Some of the 4bbl hp engines also came with factory windage trays installed. The heads are basicly the same for 2bbl and hp 4bbl motors for all intents and purposes. As Ken mentioned i prefer the later 452 head castings because they respond better to mild porting and have hardened exhaust seats for unleaded fuel. Unless you machine the block specificly for tight quench, the closed chamber 915/516 heads have no advantage. With a 9.5:1 compression ratio an open chamber iron head is fine on pump fuel.

Ron

[Ghoste]

What are the cam specs between the two and the four just out of curiousity?

[javakmcharger68]

Got a question for you all, if you take off the heads to find mud full in the cylinders. How does this happen or is it something that just happens over time? I noticed this taking the 67 apart, & in one cylinder the piston was rotting apart. I assume that the 906 heads that came off this engine would need hardened seats to be useable also. I got a raw deal on this one. Thanks

[Ghoste]

I would say someone dragged it out of a swamp.

[javakmcharger68]

I wanted to write that but I thought I better give the guy the benefit of doubt. When looking at it, that was the idea that first pops up. Thanks

[Ghoste]

So how bad is it?  Can you still use it?   And yes, I would probably harden the seats.

[Chryco Psycho]

cam specs for the 2 bbl are - intake 256* , exhaust 260* , overlap 32* , approx .430 lift
the magnum / 4 bbl specs - intake 268* , exhuast 284* , overlap 46* , 450 / 458 lift

[Ghoste]

Okay, thanks Neil.  I see some of those specs now in the fsm but not all of them  Am I looking in the wrong place or are you getting them from another source?

[Chryco Psycho]

all the duration specs are in the FSM , the Mopar performance catalog has the magnum cam listed with lift , the same duration on the Mopar grinds as the 2bbl grind has .430 lift

[Ghoste]

Okay, I see them all now.  Thanks.

[javakmcharger68]

Yes thanks Chryco Psycho  for the specs. Gives an idea what the big differences are between the two. Thanks

[javakmcharger68]

What are steel cranks selling for, for a 383 or 440. Thinking maybe if the crank is good selling for a 440. I know the main journals look good so & rods I did not check yet. Trying to figure out how to get the bottom end out with the damage that is there. The pistons will not move so I can't get at every rod cap yet. Oh, & I was saying on a different subject that a 400 that I have has 452's. So what are a better head & why. The 452 or 906???

[cudaken]

 I have a 85,000 mile 383 Road Runner crnk listed here with the rods for $100.00 and no hits. I will need to check my records but I think I paid $150.00 for a none cut 440 steel crank of E-bay.

With E-bay, you never know. Had a bidding war on some piston's I won. Higher than what I was hoping but lower than from the speed shop.

                             Cuda Ken

[Chryco Psycho]

Really any Mopar big block heads is good , they are all similar in flow , the 906 has a marginally better intake port floor & the 452 has hardened seats which get ground away if you rebuild the heads