The engine had 23,000 original miles. Came out of a wrecked charger. It was stored for 50 years. It was pulled apart re ringed and honed....The heads were cleaned up and the valves were reseated. Crank was polished and put all back together. That's all the info I have. It's all original down to the original date coded Carter AFB. I have not done a compression test. Like I said it runs good just want a little more rumble.
You need to to a compression test because; every bigger cam will reduce your cylinder pressure about 5 psi.
5psi at 4000tpm is hardly missed.
but 5psi at 2000/2200 your stall speed , is a big deal
and the lower your pressure, the softer your throttle response
If you are starting from 135psi, then 130 will be crap for power at 2200
If you are starting from 155psi, then you can afford the 5psi loss.
You say it runs "good", but that is totally without qualifiers. You have no baseline against which to measure "good". "good" is arbitrary, and very nearly meaningless to anyone but yourself .
Here is a number
Static compression ratio of 9.0:1.
Ica of 72*@4000 ft elevation
Effective stroke is 2.41 inches.
Your dynamic compression ratio is 6.71:1 .
Your dynamic cranking pressure is ......................... 109.24 PSI.
V/P (Volume to Pressure Index) is ................................. 90
This shows your 9/1 engine at 4000 ft elevation, with the 284/484/114 cam installed 4* advanced. The thing I want you to notice is the VP of 90. At sealevel this is what a 225 slanty puts out, so from stall to about 3000 rpm, your 383 will perform like a 225 slanty.
Read about VP here;
V/P Index Calculation
The first thing you are gonna need to do is get a 3000stall TC , and the second is 20 to 30 percent more rear gear.
Next ; notice the pressure is 109psi. Talk about a lazy throttle . The Third thing you are gonna do is replace that Mopar carb with a double pumper.
You want to do all this for a little rumpidee-rump in the exhaust?
Next consider the midrange power; 109psi is pretty weak. That's OK you said you didn't care about the power. That's good because in third gear there won't be any, and Second gear is gonna be sooooft .
So the Wallace Calculator predicted 109psi ,at 72*Ica, and 9/1 Scr,@4000 ft elevation. That means the current pressure might be 114 at most.
This is why you HAVE to do a compression test, to know what your starting point is.
That cam is gonna be doggy even at 10.5Scr...... because of your elevation
Here is the same engine at 10.5
Static compression ratio of 10.5:1.
Ica of 72* @4000 ft
Effective stroke is 2.41 inches.
Your dynamic compression ratio is 7.78:1 .
Your dynamic cranking pressure is 136.64 PSI.
V/P (Volume to Pressure Index) is 112
Notice the VP is still only 110, and a 318LA makes more than that.
Here it is at 12/1
Static compression ratio of 12:1.
Ica of 72*@4000ft
Effective stroke is 2.41 inches.
Your dynamic compression ratio is 8.85:1 .
Your dynamic cranking pressure is 164.89 PSI.
V/P (Volume to Pressure Index) is 135
This is the limit for pump gas and Tight-Q, and that spells a custom-engineered engine...... and the VP is still only 135............... Fun starts now but only because you have the pressure. Typically fun starts at 140VP.
The point is at 4000 ft elevation,you just can't throw a 284/484 into a low-compression engine, and expect "drives good".
If you install a big TC , then VP doesn't mean much, but
With a stock-type TC, the new reduced cylinder pressure will lower the stall even further,making take off sluggish. Furthermore, If you don't have the pressure you will be driving deeper into the throttle ALL the time to, to find enough power, to satisfy your driving needs. And the bottom line of that is ; the combo sucks gas.... bigtime.
At 4000 ft elevation there is no happy IMO, solution to your craving for rumpidee-rump.
Well maybe; this might be a good time to mention ThumpR or Whiplash
