I think its around 2002-2003. About the same time Florida_70Bee's....Bee was featured in Mopar Muscle.

Here is his combination, and according to an online calculator, he's making around 325 at the rear wheels based on the weight and speed. Note that he runs aroudn 13.50 in the 1/4 with a PURESTOCK legal standard bore, #'s matching 383.

Getting 400-450 horse should be fairly easy.

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Purestock 383


"have done this same combo in my 70 Bee

To get the C.R. up you will need to deck the block and mill the heads and I think Speed Pro offers a correct flatop piston

Here are some specs on my combo

The block is the original std bore 383
I am using the original cast flatop pistons standard bore.
Speed pro plasma moly rings
The block has been decked to a piston to deck clearance of -.006. (NHRA stock elim minimum specs are -.004 (for a 70 383 335hp) in untouched form I measured the piston to deck at -.050
I am using a Fel Pro steel shim gasket for a 413 which has a compressed thickness of .020
The heads are stock unported 906's with stock size 2.08/1.74 valves with a good valve job. Additionally the heads have been milled to 80cc's (the NHRA minimum is 79.5cc's and in untouched form they were 88cc's)
All this adds up to a measured compression ratio of 10.12:1. This number would be higher with a .030 or .060 piston. Originally in untouched form I measured the CR at 8.44:1 (a far cry from it's 9.5:1 advertised CR.

The cam is a Mopar Performance stock resto cam for a 440 6 pack (same dimensions as the original 383 magnum cam except it uses a 3 bolt cam gear instead of the original 1 bolt)
The intake is the unported original.
The carb is the original 585 cfm holley
The converter is a dynamic 11 inch that stalls at 2300 (like the original converter
The ignition is a combination of Mopar Performance elctronic and FBO Ignition Box, and Coil

The exhaust is a TTI 2 1/2 H pipe with Dynomax Ultra Flow Mufflers
I am running a 4.10's in the rear and I am using a pinion snubber and I clamp the front segment of the original springs.

The car weighs between 3975 and 4015 lbs with me in it depending on the fuel load. I leave the line at around 2000 rpms and roll into the throttle (I don't stab it at green as I am running F70-14 Polyglas's) and shift between 5600 & 5700 and it goes through the traps at 5600 rpms. "
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So John, are you saying they didn't make the 450 like they claim in the Moparmuscle/Westech article? I was unaware of this if thats the case.