Camshaft selection for 383...

[superstock64polara]

I have a 64 Polara hardtop with a very mild 383
Currently the motor has a MP 284 / 484 hydraulic stick
Trouble is the static compression is only at 8.5:1 with unported 516 heads with larger exhaust valves
It runs 1 3/4 four into one pipes, a Performer intake, and a 650 vac secondary Holley
It also has a 727 with stock converter and a 4.10 geared 8 3/4 sure-grip rear
The MP 284 cam is too much for such a low comp motor, what hydraulic off the shelf stick would you guys recommend?

I was leaning towards a Comp Cams XE274H
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=708&sb=0

Love to hear from some real world experienced people on cam selection


Chris

 

[Dennis H]

Can't help with 383. For my 440 it is a CompCam CRB XE275HL-10. Sweet. Lope like you dream of. Rolling waves when arriving at a car show.

 

[hemidart1]

these cams rock with lower compression and sound wicked at idle
http://www.hughesengines.com/Index/products.php?browse=search&search=hmc&partid=25115

listen here
http://www.youtube.com/watch?v=akNAKzkSNcg

 

[62 Dart Convertible]

Hi Mate. Have you considered using closed chamber heads to bump your compression and leaving the cam? With such low compression, it is very sensitive to excessive LSA and you should limit it to 112deg minimum. The XE274 has 110deg. I personally would go the way of bumping compression, and consider a higher stall convertor too... Your combo would be great and perform very well!

 

[superstock64polara]

Hey there, I'm running 516 heads which are closed chamber. The pistons are way down in the hole and my effective static compression is 8.5:1. I could mill the heads a little but would rather swap out the stick for something with a more modern profile that works with lower comp motors.

Hi Mate. Have you considered using closed chamber heads to bump your compression and leaving the cam? With such low compression, it is very sensitive to excessive LSA and you should limit it to 112deg minimum. The XE274 has 110deg. I personally would go the way of bumping compression, and consider a higher stall convertor too... Your combo would be great and perform very well!

 

[Dennis H]

Can't help with 383. For my 440 it is a CompCam CRB XE275HL-10. Sweet. Lope like you dream of. Rolling waves when arriving at a car show.

Someone pm'd me on this and I lost it. Send again please.

 

[lewtot184]

comp cams #21-305-4, or mopar 272-.455.

 

[Banzaiii67]

comp cams #21-305-4, or mopar 272-.455.

X2 ^

I would not use the XE274H cam with that low of compression. I have it and I have issues with vacuum and a/f mixture because of the 13* of overlap

Another cam to consider is this one. It's got 4* overlap on 108 Lobe Separation, and take advantage of the .904 dia lifter

http://www.summitracing.com/parts/hrs-721141-08/overview/make/chrysler

 

[bigaadams]

actually what is your intent with the engine..street or strip and or street with the ocassional goose...is the cam going to be happy with the rear ratio you have now or is it also intended to be changed
Is the cam going to be compatible with the induction system you now have or is there change going to be made here
How about the exhaust of proper size
as mentioned already the very heads so will just mention in passing...
how about your tranny..if automatic..is you converter up to the job?
is you ignition going to be adequate..or will you need a longer dwell time now (electronic or standard points???)
are your valve springs up to the very task also

lots more questions to be asked and answered to get to the single answer you are asking now as all this works together for proper performance..

first figure out what you want out of the car..the rest is plug and play...

 

[Junky]

these cams rock with lower compression and sound wicked at idle
http://www.hughesengines.com/Index/products.php?browse=search&search=hmc&partid=25115

listen here
http://www.youtube.com/watch?v=akNAKzkSNcg

hemidart1 knows his stuff. I run a Whiplash in my 383. Damn nice cam for the street and strip. It is designed for low compression engines, and it works! Rumpy idle and winds quick and fast to 6000 RPM. I run 275/60R15 rear tires. From a stand still, just stomping on the go peddle, it's blow them tires up in smoke for quite a way down the street. Does a little wiggle from tires spinning when I hit 2nd gear. Call Hughes Engines and talk to them about it. It'll out do all the Chevy lobe cams. You won't regret it.