What are the differences in 1970 383 engines?

[NJRR]

There are 3 configurations listed for 383's in 1970. What are the component differences that give the different performances and what limitations are there between them? (besides the obvious carb differences)



Engine/Disp.-Carburetion-Bore/Stroke-Compression- RatioHorsepower @ RPM-Torque @ RPM-Normal Oil Pressure
V8-383 2-bbl 4.25 x 3.38 8.7:1 290 @ 4400 390 @ 2800 45-65
V8-383 4-bbl 4.25 x 3.38 9.5:1 330 @ 5000 425 @ 3200 45-65
V8-383 4-bbl 4.25 x 3.38 9.5:1 335 @ 5200 425 @ 3400 45-65

 

[69Bee]

The 330HP version is the base 4BBL motor with stock cam, and the 335HP version would be the equivalent Magnum version with the hotter cam.

 

[NJRR]

What about the 2 barrel/290HP version?

The 330HP version is the base 4BBL motor with stock cam, and the 335HP version would be the equivalent Magnum version with the hotter cam.

 

[monaco66coupe]

The two barrel had the lower compression,and single exhaust. The windage tray, double row timing chain was also absent. The two barrel cam was even more mild than the 330HP engine.

 

[Roadbird]

So what about the 383 HP 335 horsepower 4 BBL carburetor? 1970 Roadrunner.

 

[monaco66coupe]

1970 383 engines

The 1968-70 335 HP roadrunner had the cam of the 440 HP from 68'. In a book by Paul Herd, he describes how Bill Brownlie, the designer of the roadrunner wanted something different for the 68 roadrunner and Superbee to separate them from the other cars. So, the RR and Bee had the HP stamp, and 440 magnum cam and springs. The models also had the 440 R/T transmission, 2801541 Until the spring of 68'. The later trans was also the newer 440 R/T transmission. The charger and Satellite 383 didn't have that Transmission. Even with the cam change However, During dyno tests, they were shocked that this added only 5 HP to the Magnum engine. As Brownlie thought it would steal sales from the RR, They didn't stamp HP on any 383 chargers or sport Satellite 383 engines, even though they had the H' in the VIN. They did have the 10.0:1 compression, but the milder cam, which explains the lower RPM. (5200) I found it true, as I had an original 69' H code charger. No HP stamp, single springs, lower lift, no windage tray. It did have the 10.0:1 compression, and dual exhaust. It also had a 2:76 rear end, not exactly drag race material. The book Is very Informative:
"Muscle car History"
Charger, Roadrunner and Superbee by Paul A. Herd and Mike Meuller ed.1994 (Motorbooks International)
I hope this is helpful,, Paul Herd also published a detailed restoration guide, so if you are restoring one of these models this book is a gold mine of Information.

 

[Meep-Meep]

The Road Runner came out first in 68 so it got the "hot cam" that later got named the Road Runner cam. But if you ordered a Road Runner with A/C it was rated at 330 HP not 335. Don't know why unless they figure the compressor was the reason.

 

[bee71]

I thought the 335 hp had the 440 heads and that was the difference also.

 

[Cranky]

They all had 906 heads....and in 70 most came with the valve spring package too. Don't remember what size carb was on it but the AVS was on my 70 Challenger and it didn't run all that good either. I mean, it ran well but not like the 335 horse motor. Mine had the dual exhaust etc but wasn't an RT.

 

[Roadbird]

So if my 1970 383 HP came with A/C it's not 335hp? Rather it's only 330hp? Or this just applies to the 68 RR base engines. Which were 383 magnums non HP.

 

[monaco66coupe]

I didn't see anywhere in the restoration book where it addresses A/C cars not having an H.P. stamp on the block. From what I read, if it is stamped, then all the features listed before are in that engine. I will read through it again,(it could be an oversight in the book) but The best way to know is if you have A/C, look for the HP stamp on the block, and check the VIN#. if the stamp is there, and the VIN matches then Chrysler didn't delete the stamp. if not, then they did. In my case, with any car I own, if I have the the correct vin on the block, I'm good! The book doesn't cover E bodies, But I read an article somewhere that the 70R/T challenger had the HP stamp, but the four barrel Gran coupe didn't. I have asked the publisher for the applicable E body book, but I really don't know those very well, and don't own one. Anyway, they haven't responded yet. it was all about marketing anyway, and we all know what these cars are worth today. The book is well worth buying, as it has pictures, part numbers, and applications for every nut and bolt for the 68-70 B bodies and their 383 and 440, and 6BBL HP engines, transmissions,rear ends, Interior,decals, it goes on and on. Hell, that book is in THE bathroom at all times! Unless I'm in the shed.LOL

 

[tallhair]

So if my 1970 383 HP came with A/C it's not 335hp? Rather it's only 330hp? Or this just applies to the 68 RR base engines. Which were 383 magnums non HP.

By 70 they had bumped the HP down to 330 for the RR w/o the A/C and it was a little less compression too .. can't recall 9.7 ??? From memory so check out the stock specs from mymopars http://www.mymopar.com/index.php

welp i went and looked it up myself .. no advertised drop in HP for 70 but the compression dropped to 9.5

ngine/Disp.​

Carburetion​

Bore/Stroke

CompressionRatio​

Horsepower @ RPM

Torque @ RPM​

Normal OilPressure​

1968

V8-383	2-bbl	4.25 x 3.375	9.2:1	290 @ 4400	390 @ 2800	45-65
V8-383	4-bbl	4.25 x 3.375	10.0:1	300 @ 4400	400 @ 2400	45-65
V8-383	4-bbl	4.25 x 3.375	10.0:1	330 @ 5000	425 @ 3200	45-65

1969

V8-383	2-bbl	4.25 x 3.38	9.2:1	290 @ 4400	390 @ 2800	45-65
V8-383	4-bbl	4.25 x 3.38	10.0:1	330 @ 5000	425 @ 3200	45-65
V8-383	4-bbl	4.25 x 3.38	10.0:1	335 @ 5000	425 @ 3400	45-65

1970

V8-383

2-bbl

4.25 x 3.38

8.7:1

290 @ 4400

390 @ 2800

45-65

V8-383	4-bbl	4.25 x 3.38	9.5:1	330 @ 5000	425 @ 3200	45-65
V8-383	4-bbl	4.25 x 3.38	9.5:1	335 @ 5200	425 @ 3400	45-65

1971

V8-383	2-bbl	4.25 x 3.38	8.5:1	275 @ 4400	375 @ 2800	45-65
V8-383	4-bbl	4.25 x 3.38	8.5:1	300 @ 4800	410 @ 3400	45-65

 

[monaco66coupe]

. I now realize this restoration manual also is very thorough with the 71', and all the 318 chargers beginning in 1968. it looked like the 70' was still the same across the board, but 71' went to 8.5:1 in the 383,(300) and 440 to 370 Hp. There were three of those as well. and down they went. And there were various models depending on emissions, so it got murky. All I'm really sure of is my 55' flathead had 117HP. Yea!(7.1:1) depending on the day,,,,,,,,,,,,