cam suggestion for hi-comp 340 and 3.23 gears

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TimDart

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Hi guys, a bit of a cheeky request as the car involved is B body, 73 Roadrunner. I did ask over on forbbodiesonly, but only got one response which was helpful, but Id just like a wider range of options.
Car has real 10.1 compression with the smaller valve J heads, stock rocker gear which id like to retain, original 340 manifolds and dual pipes. Rear is 3.23
Looking for a good cam that will pull this heavy old B body (my old dart is now sold), I can upgrade convertor if required. Car is for street use and has power brakes.
Thanks in advance
 
High lift comp or voodoo or similar 268 or 274 after that you start losing a lot of bottom end for top end.
 
I think the problem you will run into is a camshaft that works the brakes and makes the low end you need, might cause some ping issues with the high static. It will take some careful ignition and carb setup to run well on pump super. I'd use the XE268 Comp. The Lunatis require dual springs and those will be a problem wit the stock stamped rockers.
 
According to the parameters laid out, it would seem you could go as far as a cam that has up to 224º duration at .050". You may need a vacuum reserve for the brakes and you may be wanting a higher gear ratio (like 3.55:1) to take advantage of the cam. A safer bet would be 214º @ .050" as a limit.

FWIW: Comp Cams recommends you replace stock valve springs if you are going to use an Extreme Energy cam.

IMHO it is very easy to over-cam and over-carb a street engine. It shows as a lack of throttle response in the low to mid-range.
 
A wider lobe center(112,114 ) would help,on detonation issues. So would a bigger split,between intake and exhaust duration. Crane makes a nice cam,216/228 @.050.112 lobe centers,454/480 lift.Would work great ,with stock replacement 340 springs.Nice cam,my.02.
 
Thanks for the clear advice, guys. I'm keen not to over cam the car. Currently the previous builder has mismatched the parts. It has a purpleshaft cam and 318 convertor in it (!)
The cam suggested above is;
http://www.summitracing.com/parts/crn-693941/overview/make/plymouth

This looks like astep up from my old Dart which had a Comp XE262 grind in it.
Would the Crane cam listed above respond well to a 2000 convertor?
 
Yes, if the distributor has a curve job done.P.M ,Rumblefish,Crackedback.Easy to tune.
 
My buddy had the exact same car, but with 3:55 gears, and we installed a mopar 484 purple shaft in it, and it was great. The cars power brakes still worked fine and the car had a nice little rumble, with dual flow masters on it.
 
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