My 383 is weak!?

1mopar4life said
Thanks Cuda, I believe it has a Performer RPM intake by the look of it but it has all been painted in the past so I'm not exactly sure. I have a stock stall converter in it as well. I am certainly going to upgrade the ignition as well as swap the cam out and change the rear end for one with better gear. I just have to decide which cam will do best with the combo I have in it.

First thing that needs to be said is that 383's love to rev, maybe not as high as a good flowing 340 but I take mine and the ones before it to 6200 all the time and that's where they perform. A 383 is not a lugging engine thats what 440/motorhome engines are for and sadly this 383 has been built as a small scale 440 and it don't like it much. Next there is nothing wrong with the orange box ignitions, cept you should carry a spare box and it will go strong to the low 6000 range. MSD's are good for engines pumping a lot more HP, fuel, and RPM than this engine will ever see and I doubt you'll ever feel a difference putting an MSD on this engine if it was already running good and strong. So we need to know what heads are on this engine. As mentioned before all BB heads will fit either the 383 or 400 or 440 whether they are the 915's, 906's, 452's, 902's and there are a few more so remove the tappet covers off of both heads and give us the last three numbers of the casting number. For all we know you may have a couple small exhaust valve 915's or 516's or one of each, yea you can mix and match them. All these heads had there own good and bad points. Next if you haven't got an RPM Performer then get one, the 383's love them and for what you're building anything else will not match up formula wise. Holley 750 minimum either the vacuum secondaries or double pumper, I prefer the DP'r cuss I build these engines to ignite off the line ie. no stumble. Next, minimum 1 3/4 " primary header pipes with 3" collector and with that truck that shouldn't be a problem. Comp or better cam with an effective lift of .480" to .510" lots to choose from. Next 9 1/2" 3000 stall converter. Rear gears of 3.55 are the minimum I'd go, good on the highway (60mph at 2700 RPM) with a fairly tall 275x60 tire but again the 383 would probably love the 3.91 even more. Put her all together and get the timing just right, start at initial of 12deg with full centifugal at 38 and all in between 2200 and 2400 RPM, and proceed to melt the tires off that truck. Here's the article mentioned that highlights the potential of the 383 without having to spend a ton of money. Don't forget that if you really want to make her rev then you'll have to invest on good roller rockers cuss the accuracy of the stamped steel is laughable. Example, they're supposed to be 1.5 ratio but infact I've physically measured them and got 1.42-1.46 and that's brand new out of the box.

http://www.moparmusclemagazine.com/techarticles/mopp_0209_383_engine_restore/index.html