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 Post subject: Cam shaft ID question
PostPosted: Sat Jul 14, 2012 3:09 pm 
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2 BBL ''SuperSix''
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Joined: Mon May 03, 2010 9:18 pm
Posts: 17
Location: San Diego Ca.
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I have a block with a cam in it, the back of the cam is stamped rpd3 km8, can anyne enlighten me as to the specs?

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68 Barracuda Fastback \6, auto
64 Valiant hardtop \6, Hurst 4 Spd
63 Valiant Vert \6, Hurst 4 Spd
65 Dart GT \6, console auto
68 Chrysler Town and country 440 Auto
72 Swinger 318 AC/Discs
2010 Challenger R/T
2013 Dart Rallye


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 Post subject:
PostPosted: Wed Aug 08, 2012 8:10 am 
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2 BBL ''SuperSix''
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Joined: Mon May 03, 2010 9:18 pm
Posts: 17
Location: San Diego Ca.
Car Model:
trying to bump this one...I cant seem to get this engine to run right. Does anyone have the specs on this camshaft? I am wondering if I have the valves set right. The cam is stamped RPD3 across the top and KM8 on the bottom when looking through the rear hole before the plug was tapped in.

_________________
68 Barracuda Fastback \6, auto
64 Valiant hardtop \6, Hurst 4 Spd
63 Valiant Vert \6, Hurst 4 Spd
65 Dart GT \6, console auto
68 Chrysler Town and country 440 Auto
72 Swinger 318 AC/Discs
2010 Challenger R/T
2013 Dart Rallye


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 Post subject:
PostPosted: Wed Aug 08, 2012 8:31 am 
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Joined: Mon Oct 14, 2002 4:32 pm
Posts: 4880
Location: Working in Silicon Valley, USA
Car Model:
An RPD3 is the Melling Tool aftermarket version of the factory Hyper-Pak cam.
You would have to run a static compression ratio around 11 to 1 to get a decent DCR with that cam.
How is your engine currently set-up? What is the current compression ratio?
DD
Quote:
In 1960 Plymouth introduced the Hyper-pak 6 which used a more radical cam (PN 2205620).
This cam has a duration of 276-268-44 degrees and a lift of .430".
This camshaft is no longer available from Chrysler but can be purchased from Melling Tool Co., Their part no. is RPD-3...


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 Post subject:
PostPosted: Wed Aug 08, 2012 5:57 pm 
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2 BBL ''SuperSix''
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Joined: Mon May 03, 2010 9:18 pm
Posts: 17
Location: San Diego Ca.
Car Model:
I actually have no history on the engine at all other than I bought it from the family of a man that rebuilt it for a project he was working on and then died before he could install it. I grabbed it, put my oil pan and pick up and my intake and exhaust and dropped it in my 63 Valiant vert with a 4 speed. Filled it with fluid and static timed it and got it to start, it ran terribly so I adjusted the valves to .12 and .21 (cold as a starting point)and got it to run just a "little better" but it seems I have what I thought were carbueration issues, I've tried three different Holly 1920s and a Ball and Ball with no joy.
I think I have access to a repro hyperpack setup and still have the Dutra Duals I bought from you 20 years ago when I lived in NORCAL. (You probably don't remember me but I had a gold 68 barracuda fastback and gave you all my extra slant six stuff when I moved to San Diego).
Is my issue likely to go away if I run the hyperpack intake and bigger carb?
What should my valves be set at?

_________________
68 Barracuda Fastback \6, auto
64 Valiant hardtop \6, Hurst 4 Spd
63 Valiant Vert \6, Hurst 4 Spd
65 Dart GT \6, console auto
68 Chrysler Town and country 440 Auto
72 Swinger 318 AC/Discs
2010 Challenger R/T
2013 Dart Rallye


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 Post subject:
PostPosted: Wed Aug 08, 2012 6:10 pm 
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2 BBL ''SuperSix''
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Joined: Mon May 03, 2010 9:18 pm
Posts: 17
Location: San Diego Ca.
Car Model:
I should also mention, everything in the block is new and seems to have been built professionally. The pistons are .20 over and everything had fresh assembly lube on it. I'm a parts changing monkey but no professional mechanic or automotive engineer. I wouldnt know how to go about assessing its compression ratio.

_________________
68 Barracuda Fastback \6, auto
64 Valiant hardtop \6, Hurst 4 Spd
63 Valiant Vert \6, Hurst 4 Spd
65 Dart GT \6, console auto
68 Chrysler Town and country 440 Auto
72 Swinger 318 AC/Discs
2010 Challenger R/T
2013 Dart Rallye


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 Post subject:
PostPosted: Thu Aug 09, 2012 9:42 am 
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Joined: Mon Oct 14, 2002 4:32 pm
Posts: 4880
Location: Working in Silicon Valley, USA
Car Model:
Adjust the valves as loose as possible with-out "ticking".

This will be somewhat difficult seeing that the engine likely has a choppy idle and will not want to idle down enought to do a running adjustment.

Start with .018 on the intake and .024 on the exhaust and test.
If no "clatter"... try .020 and then .022 on the intake lash.
The goal, find the end of the "lash ramps" so you can "kill-off" some of the cam's duration.
Doing this will increase your low rpm cylinder pressure, reduce intake track reversion & increase manifold vacuum.


Once you have done that, check the manifold vacuum at idle & the cranking compression, in PSI. (compression test)
DD


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 Post subject:
PostPosted: Thu Aug 09, 2012 5:50 pm 
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2 BBL ''SuperSix''
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Joined: Mon May 03, 2010 9:18 pm
Posts: 17
Location: San Diego Ca.
Car Model:
thanks, I'll give it a try and respond. I may have to do the brakes on my dart first (its what I/m driving while this is down).

_________________
68 Barracuda Fastback \6, auto
64 Valiant hardtop \6, Hurst 4 Spd
63 Valiant Vert \6, Hurst 4 Spd
65 Dart GT \6, console auto
68 Chrysler Town and country 440 Auto
72 Swinger 318 AC/Discs
2010 Challenger R/T
2013 Dart Rallye


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