383 4Bbl unique specs

[66 Meteor]

Trying to discover what else is unique to the 383 4bl from the 383 2bl. Is this related to the B-383 and the RB-383, however, I believe this is a completely different spec. So back to the 4bbl vs 2bbl?

 

[detmatt1]

RB is raised block and 383 has always been a B engine.

 

[Cranky]

Actually, the 383 came as an RB for one year only....think it was 59, the first year it was introduced. Anyways, the 2 bbl motors were usually lower compression. The Magnums were a bit different too with different cams, heads etc and even had dampers on the valve springs....

 

[YY1]

IIEC There was an RB 383 in 1957.

In 1966 the 383 4 bbl was the only offering in a B body, and was 10:1.

In 1967 the 383-2 was a 9.2:1 comprrsion setup while the 383-4 was a 10:1 motor.

 

[Cranky]

The wedge design big blocks first showed up in 58......as a 350 B series engine.

 

[Meep-Meep]

In short, it's compression, valve timing and distributor curve.

 

[Photon440]

http://www.allpar.com/mopar/b-engines.html

 

[696pack]

IIEC There was an RB 383 in 1957.

In 1966 the 383 4 bbl was the only offering in a B body, and was 10:1.

In 1967 the 383-2 was a 9.2:1 comprrsion setup while the 383-4 was a 10:1 motor.

This is all true actually through the 1970 model but in addition to this in 1968 they also built the Magnum or Roadrunner engine. They were the same engine with different marketing names and had a different carb and cam from the 330 h.p. engine. Oddly in the 69 Plymouth Data Book it shows the
383-2 (290 h.p.) as the Commando engine and the 383-4 (330 h.p.) as the Super Commando and the 383-4 (335 h.p.) as the "Roadrunner engine."

http://www.hamtramck-historical.com/images/dealerships/DealershipDataBook/1969/69_Belvedere0011.jpg

 

[Photon440]

The "roadrunner engine" was different from the regular 330 hp. 4bbl 383 in a few ways - it used 440 heads and valve springs, and the high perf. exhaust manifolds, 440 cam and the windage tray. It was only rated at an extra five horsepower but breathed and pulled a lot better on the top end, with hardly any extra production costs.

Dodge started using this version of the engine when they saw the road runner sales and introduced the SuperBee.

-=Photon440=-

 

[YY1]

Uh Oh, there's that "440 head" phrase again.

 

[Cranky]

Well, in 67, the 383 didn't have the '440' head but in 68, all the big blocks (383/440) had the same head....which was an open chambered 'large' valve head. The high performance engines had dampers on the springs and that was about it for the 440/383 head. Chamber size was the same. The 67 440 head (915) with the closed chamber and the springs with dampers didn't show up on the 67 383 engines and I don't care what Allpar says about it lol

 

[Meep-Meep]

Yep, it's only referred to as a 440 head because the 67 440 HP was the first to get the then new 915 heads with big valves. So when the 383 RR engine came out they used the heads and stuff off the 440 (by that time the 68 440 HP had open chamber heads). The Road Runner engine was the highest output single 4 BBL 383. Yes, the Magnum was the same thing, but Plymouth was first with it so they got the extra 5 HP - like it makes a difference.

 

[YY1]

Allpar has quite a few errors, as well as a fare share of illogical statements, and quaestionable timelines.
Mymopar does too, but not as many.

...and I'm no staistician, I only play one for fun sometimes.

Perhaps the OP can tell us what year(s) he's concerned with.

There's definately 3 major groups- pre 66, 66/67, and 68-71.
You could even argue for 68/69, 70, and 71 I think