Waking up the 1971 383 Engine

[Crewcabstripper]

I’m looking to do a little work on my 71 D200 with the factory 2bbl 383 and 727. Not wanting to get into a full rebuild. But would like to wake it up a little. Possibly add a 4bbl intake, headers, possibly a double roller timing chain and new cam. Only thing done to engine currently is I converted from points to a pertronix ignition. My question is what’s the best combination of these parts to go with? Hoping someone has done this already and has a proven parts list. What’s a good set of headers that fit in these trucks with my engine also what’s the biggest lift cam before clearance/performance loss starts?

[Jim100]

I had a 1970 318 with un known miles on it. I decided to wake it up like you are talking about. aluminum intake and four barrel with some headers.
Maybe it was just a coincidence but I blew rings off a piston within two weeks. Before it failed I could really feel the power increase though.
jim

[Roxyflash]

Can gain alot of power just getting a three angle vavle job on your heads.Headers i used the hooker headers for these trucks.I would get the mopar ignition get rid of points.Get a good dual plane intake 750 size carb.Cam i used the purple cam but didnt run well till i got the 915 heads.I wouldnt go to big on cam if you got dished pistons.My motor has flat top pistons and is bored .040 over.

[Conrad]

I agree with above - I'd start with cheapest and 'havta' first. You'll spend more money on this than you think.

I have a (very) low compression 78 440. I needed to replace my coil and swapped in the Pertronix + OEM-style 'dual-spark' box + new plug wires. It ran smoother but can't say I got any performance out of that.

I recently swapped in a new intake and carb. Easy to swap but linkage can be a hassle if you don't already have the parts. I have a 440 - so bought a Performer 440 + Thermoquad 850 rebuilt off eBay for 150. I already had a Thermoquad on a cast iron manifold. Good that it was compatible with the factory linkages that was on the setup previously. I think the engine has a stock cam with rebuilt heads, but its plenty powerful obviously. Just the intake swap is +15 HP.

I had a 318 Scamp with a cast iron manifold and single barrel carb. I swapped in a Performer with a 600 com Eddy and had to use a fuel pressure reg, and a lokar carb/trans linkage. Intake/carb were used (people often pull carbs that are fine) so they were cheap, linkage was not terribly expensive but just as much as the intake/carb. All easy to swap in. Made a big difference in power.

I have the cheap china shorty headers but haven't installed them. According to tests Dulcich did, the shorty headers I have may give me 5hp at highway cruising but is more higher up. But no info about the engine specs, so results will probably not be as extreme for me. http://www.hotrod.com/articles/mopp-010 ... s-headers/. I am more interested in sound right now, and will be splurging on fancier exhaust in the future but just for the sound-fun vs. power. That will probably happen all at once, but not before I solve drivability/reliability issues.

If you do the cam, you'll swap the timing chain at the same time. An RV grind cam will make more power at the lower end and help avoid any need to get fancy on the heads. Cam will make the biggest difference if your engine is set up for higher compression, heads won't make much difference for you IMHO.

[DavidPope]

On a big block Dodge the best street manifold is a Performer RPM with an 850 cfm carb. This will give around 50 hp over stock 4 barrel.

[Conrad]

I agree there. If I were to go Edelbrock carb then I would do the Performer RPM. The Performer 440 was designed for the Thermoquad 850 I have so I went with that. I also have a low compression ratio 440 so changes wouldn't be that big for me.