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I continue seeking guidance on a replacement camshaft and related items in our ’64 300K ram engine. The existing camshaft had a lot of pitting on the lobes. I want to retain the solid tappets and adjustable rockers and find a cam that will provide operation and performance similar to the original. I want decent idle, good vacuum and good drivability.. I found the below-referenced pages on the club website to be very thorough and helpful and went back to looking at the multitude of cams available. I found the Comp Cam at this website to come closest to the original specifications of lift and duration: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=725&sb=0 This is what COMP says about it: Solid-Good with stock converter & comp. Near smooth idle in 440. Works good with 650-750 CFM carb. Excellent torque. Specifications (Intake/Exhaust): Comp Stock-AMA Spec’s Stock-Factory Drawing Duration 270/270 268/268 268/268 Lift .468”/.468” .445”/.452” .444”/.450” I claim no experience or insight on camshaft selection and did not find any other mechanical-lifter cam with anything closer. Everything else had higher lift which I guess might produce more horsepower, less vacuum and rougher idle. So, I ask: · Does anyone have actual good or otherwise experience with the referenced COMP cam or any other replacement camshaft for a ’63-’64 ram engine? · Does the slightly higher lift put valve interference with piston tops at risk? I did note a few nicks in the piston tops of the ’64 300K engine from the parts car I bought. · Any experience issues with COMP cams in general? · Since I have a factory drawing for the cam, is there any interest in having some precise replacement cams ground? The factory drawing has lift to five decimal points at one-degree increments. · The 300K Supplemental Service Manual shows valve and valve spring specifications http://www.summitracing.com/parts/cca-k21-246-4/overview/ I found the comparison of valve spring loads between the hydraulic-tappet Firepower 360 and the mechanical –tappet Firepower 390 engines and the with the same indicated 0.430” compression to be interesting and am wondering if ram-spec valve springs are available or particularly necessary? AMA specs and factory supplemental manual specs differ slightly, possibly due to typo(s). · And, are the spiral-type surge dampers that fit inside the valve springs common items and readily available? Summit carries this cam with optional lifters and valve train items: http://www.summitracing.com/parts/cca-k21-246-4/overview/ Thanks and best wishes for a Happy, Healthy, Prosperous and thoroughly C-300-K’ly New Year! Rich Barber Brentwood, CA (Convertible weather here) From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of C Bilter John and all- The attached from the club website is an old article but might be helpful in addressing some of your questions re. the original cam specs. http://www.chrysler300club.com/tech/cam/gk.html And, yes, you would be correct that the J cam would have been a little “hotter” than the F (375 hp hydraulic) cam as far as lift but same duration and less overlap. The J was faster in high speed acceleration (for example 0 to 100 mph) perhaps more likely due to lighter weight than the F and especially with the use of short rams with exhaust headers (vs. long rams and log exhaust manifolds) and perhaps the slightly larger exhaust valve size and larger 2.5 in exhaust system, and certainly the solid lifter/cam setup allowed for higher rpms as well and the setup was tuned to a 3600 rpm torque peak with the short rams vs. 2800 rpm for long rams. The F Special (400 hp solid cam) was clearly more aggressive (ie. tuned for high rpm power and less low end torque) than the J/ram K cam. The F Special was intended for high speed racing, not regular road use; whereas the J is perfectly suitable for the road. Carl Bilter Cub J consultant From: John Grady Sent: Monday, January 06, 2014 10:05 AM Cc: 'Jean-Yves' Subject: [Chrysler300] Cam specs different years. I have run into some issues trying to identify 300 C or D cam specs, I have 2 what are claimed to be 300D cams, but have no ID beyond 3 numbers stamped poorly, near gear , in rough part of cam casting..sound right? Any one have a C or D cam they know is real , with description? I do not have those stamped numbers handy. This brings up looking in aftermarket; only 392 “in production” “listings” seem to be Comp Thumper series, but those are hydraulic for 392. In looking more, hot heads has a 280 cam , solid and hydraulic, from which info I ordered a hydraulic for a non 300 392, and it turns out to be an Isky cam; Might be too much for a letter car. One person in their parts lists had a 270 Isky mega cam, both seem in right area, but was unsure what original MOPAR duration was.(for 375/380 HP cam) ; I did buy that 270 cam, price was right . That started me thinking about hi po hemi cam specs ,355 hp 354 and 390 HP 392. How hot did Chrysler go on cams? Having been young once , I also made the mistake of overcamming. Much over 280 is asking for it , especially with old Torque flight converter. (stall when you push D) Without taking sides, a modern hydraulic is probably better than a 50’s solid; for one thing you should pick up lift due to lack of running gap, for same lift spec, and under 6K modern hydraulics do not cause problems ; and adjustment of solids, esp with adj pushrods, goes away, along with a big oil soaked messy hassle.....in going through all this also found out solid lifter push rods for C D ,probably all solid A block hemi, have 3/8 balls on both ends, hydraulics 5/16 ; on my supposedly “D” engine someone used 5/16 push rods, 5/16 hydraulic lifters with D rockers and supposedly D cam, all wrong . But Hot Heads makes 3/8 by 5/16 pushrods ( might be adjustable but lock them) so you could run hydraulic cam and lifters with D adjustable rockers , using Chevy approach of one turn tight beyond clearance click. But that means set up hot and oily. Not good. This brings up more generally ram cam specs , long ram, and J cam specs. I had a J , much more cam in it than F , or so it seemed ; ----and what was in 400 HP F?- While a lot to ask, it strikes me someone in club has all this at finger tips , maybe a list? Note also that difference in duration between advertised lift and lift at .050 duration in this range is about 50 degrees ; so a 280 is about 230 at .05. Comments welcome ; it would be good for all of us to know this data; and then comes how to tell what cam is what. . Also does anyone know a simple way to tell hydraulic from solid grinds? I know it can be done at cam manufacturer by some kind of cam plotter they have , which would show accell ramps on solids before main lift event . Maybe dial indicator on lifter in partially assembled engine, and plot it ? This problem will get worse, due to parts hoards with no real history, and now they are very old piles indeed. Thank you,--as I say comments welcome. John Grady __._,_.___ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to http://autos.groups.yahoo.com/group/Chrysler300/join and select the "Leave Group" button For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylang
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