You never know when you 'll strike gold, sometimes its once you stop looking.
Chew on some of this stuff I have here related to the 1970 E Body 383 (2/4/HP) and let me know what you guys agree and disagree on. I have been reading and taking in what the members here have all stated about what the similarities & difference are between the '70 N Code 4bbl's.
Perfect timing.
This is my latest research. All facts relayed or disclosed from here forward are gathered & quoted directly & solely from both the 1970 Plymouth Service Manual and the 1970-71 Chrysler Corp parts catalogs for my only two sources on this topic that as it's stated purpose should only have meaning for '70 E Body 383 engines and is not intended for any comaparisons with '70 B or C body 383 engines, and only then except where specifically noted. This is an awesome E body site so very relevant to stay focused on E Bodys first, then the B & C Bodys. Let's see what you know.
1970 E Bodys ordered with E63 383 4bbl engines in both 330hp and 335hp levels share every same internal part (a windage tray is one part that they did not both get) listed
in the factory parts catalogs and would then share very little with the E61 383 2bbl's.
The 383 L code 2bbl must be included in here throughout for comparison to show how different it really was from a 4bbl. For starters, the 4bbl option cost more than twice as much as a 2bbl. Why such a big cost difference? Possibly because the 4bbls had the better parts like higher compression ratio pistons for one.
There are many references throughout the catalog, that distinguish a 383 4bbl individual part from that of any 2bbl item thats different. There are, however, no precise remarks at all in there to aid one in separating a high performance 4bbl item from the standard 4bbl. The complete opposite is true of the B/E/C body 440 in '70. There are plenty of references when distinguishing internal parts for the 350hp and HP 375hp versions. A good clue IMO that the 383 4bbl's shared ALL internal parts (again, only a windage tray then would separate them.)
Consider that when ordering a 1970 383 short engine or short block, be it a 'warranty' or 'over the counter' and/or 'call it what you will' block, the 2bbl versions had two part numbers to distinguish a cast (3577617) vs forged (3462613) crank versions - while BOTH levels of 383 4bbl replacement short engines shared a single part number with one another, 3462621. These short replacement engines intended for 4bbl 383's lacked a few essential internal parts like cam bearings, cam, lifters, pushrods, oil pump, windage tray - no mention at all there of them being included. Would obviously exclude every external part as well like intake, carb,etc. These short blocks may have also lacked an HP stamp on the engine number pad at the distributor.
All of Chrysler's 383 & 440 engines all shared the single 906 bare casting head & bare replacement head part number 2843904 in 1970. Two different intake & two different exhaust valves were installed into the legendary 906 heads that year. More specifically, the overall stem diameter size was the deciding factor here. 383 2bbl and 440/350 B body engine intake valves p/n 3418469 are greater in stem size than 4bbl valves p/n 3512090 by as much as .005" - thereby restricting the stem to valve guide clearance in the 906 head by the same .005." The absolute same is true of exhaust valves; 2bbl p/n 2899036 / 4bbl p/n 3512095. No BS guys...check it out in the service manual.
The 2bbl/440/350hp valves with their unique part numbers are quite obviously different pieces than the valves that an E63 4bbl was outfitted with. The 2bbl valves were actually also the same valves alotted to 440/350hp B bodys. These valves p/n 2658471 were attached to std duty valve springs that lack an added surge damper coil. The 330/335 engines shared valves & HP springs, in fact, shared the 440/375hp units p/n 2658204. My 1970 330hp 383 was found to have come through with the 440 HP springs - to offer any evidence to this being of truth. All one has to do is quickly check a '70 service manual & 70-71 parts catalog for this info above & then examine other original 330hp engines to verify. Only takes a minute to pop a valve cover off and take a pic.
'70 E body E63 4bbl engines shared spark plugs, ignition timing, idle speeds, transmissions (10" t/c with 4bbl & automatic,) 666 intake manifold, HP exhaust manifolds as well as the option of dual exhaust. They shared distributors and also shared those uniquely designed '70 vacuum advance units. With all of the above being the case, then wouldn't the 330hp motors then be pre-set up to run the same cam/lifters as the 335 hp motors, yes, and there are two cams listed in the parts catalog that apply to E body. All 383 4bbl engines shared one cam, p/n 2843564, sharing same specs with 440HP - consider first there is only one valve, cam, spring, retainer listed specified for a 4bbl in the '70 service manual. This cam lifts the intake valve to .450 (268') & exhaust to .458 (284'.) Have yet to see the cam specs that Supercuda posted earlier for '70 383 E63. I still want to hear anything he can add to help us learn more.
Known is that the 2bbl engines along with the 440/350hp engines for B body got the other smaller cam .425/.435 (256'/260') p/n 2532190.
Of note here is when ordering the correct cam in the parts catalog for E body for a 383 or a 440 - is the 'strange' reference to a .05 raised ring cam vs non-raised ring cam. 383 2bbl and 440/350 B Body engines use the .05 raised ring cam. The 440HP 2843564 cam is what was installed into all E body E63/4bbl engines is what it ALL boils down to. A factory 1970 E Body optional 383 engines ad would be nice to see to help compare.
Externally is where the two 383 4bbl's differ. Things like carbs, carb manufacturers, factory windage tray, and possibly even air cleaners. Was there a dual snorkel (330hp) v unsilenced (335hp) air cleaner difference in '70 for E Bodys? Or, did flat hood vs rallye hood make a difference in air cleaners assigned and what air cleaner did ordering a/c determine? My 330hp engine came through with a flat hood, dual snorkel air cleaner & a/c.
The 5 hp difference between the 383's in 1970 was only coming from the windage trays and/or the Holley 4bbl's plus unsilenced air cleaner alone then.