My 383's performance

[Mr Lee]

Thanks everyone for the input.

In reference to the valves being tight.  Since I have a Lunati cam and not a stock cam, but I don't have a cam card, what do I set the valve adjustment at?  I've never done it before but aren't they supposed to be adjusted to the cam manufacturer specs?  It is a flat tappet cam.  Maybe I can contact Lunati and ask them for advice. 

If my cam were advanced, would I have other symptoms besides it being a little low on power?  Would it explain why my engine likes to be at 40 degrees advanced timing?  I think most 383's are at 34-38.  I did check TDC with a piston stop and my timing marks on the damper are correct, (or maybe 1/2 degree off).   

So, I get that the 383 with it's big bore and short stroke is made more for top end.  Maybe I'd be happier if I had asked for a cam that was designed for more top end power because as it is, the cam is asking the engine to produce power in the lower range that the motor really isn't designed for eh?
So, if I check my cam and find that it's degreed correctly, do I replace it with something built more for top end?  And then put on an intake (I have a bigger carb on already) and see where I'm at before deciding on a stroker kit?   

[Mr Cuda]

My comment about cam advance was only a possible cause of vacuum fluttering.
Your comment about it liking more advance would indicate that there is a mismatch between cam and compression.
Mopars  like10-12 initial,  32-34 total timing as a base. Then add vacuum advance for mileage,  only ported vacuum source.
Flat tappet? Hydraulic flat tapper probably.  You should hear no ticking from the lifters. .040" of plunger compression when rockers are tightened.
Did you get a cranking compression number?  I forgot if you did.

[Mr Lee]

Stock lifters were solid flat tappet, yes?  I believe that's what I have.  The only changes / upgrades made on the rebuild besides the cam were hardened valve seats to my knowledge. 

Cranking compression numbers were all between 130-145psi... but if I recall correctly, I did the test with the engine cold as opposed to warm, not knowing. 
From what I read in the service manual, they list 110 pounds as being the baseline for a 383 HP.

"Your comment about it liking more advance would indicate that there is a mismatch between cam and compression"  I'm not sure I follow.  Does this mismatch refer to cam timing possibly being off? 

[Mr Cuda]

You have hydraulic lifters.  Solid lifters require adjustable rockers.
Cam manufacturers have a recommendation chart for cam selection. This is from Crower.
The mopar engine bible has more info that is good reading.

[DeathProofCuda]

Negative, if you are running stock valve train for a 383 HP motor then you have hydraulic lifters, not solid.  The stock rocker setup has no provisions for valve adjustment, as would be required for solid lifters.

Looks like I got beat to the Post button...

[Mr Cuda]

https://amortips.com/how-to-calculate-compression-ratio-from-psi/

[MKA]

Found this old article on bolt on upgrades to ramp up a 383.  Good short read. 

https://www.motortrend.com/how-to/mopp-0209-383-engine-restore/

I find my stock 383 to have good power throughout the acceleration but nothing that pins you to your seat.  It just seems to be a constant steady pull thru 100 mph ( haven't had the opportunity to take it higher).  I will have to recheck but I swear my rpm's cruising at 70 are in the 2k ish range with auto and 323 gears.  I will double check next ride.   

  Right now the car is tuned fine, starts right up and is a good cruiser.   When I get around to performance upgrades I will prioritize 355 gears and possibly the carb.     I had designs on doing headers and intake but decided after being reminded of gasket issues, heat and other figment problems along with liking the stock look, I'm good.