383 Mopar Rebuild Help

[That_1_71_Dodge]

Hello, I own a 383 mopar and am looking to rebuild it. I believe it has been semi rebuilt before as the block is blue but it’s heads and such are orange. Not all too sure but am looking to rebuild it once again. I’d like to install a bigger cam as well as pistons, not something huge like racing cams but I’d like her to have a little more power under the hood. This is going in a 1971 Dodge Charger 500, we are upgrading several things as well so no need to worry about trying to keep it stock. If someone can help me out, thanks

 

[70chall440]

What help are you looking for? You need to disassemble the block making sure to keep everything organized. You need to measure the bores to determine if they need to be bored or you can just hone them, more than likely you will need to bore it which will require new pistons.

Locate a local machine shop, hopefully someone you can work with. They will be able to tell you exactly what you need. Same issue with the heads, they will need at a minimum a clean up, lap the valves and new seals but more than likely they will need more than that such as seats, perhaps valves, etc.

There are lots of books/videos available on this issue.

 

[Don Frelier]

Strip it down to the shortblock and find a good machine shop.
I see rust in the bores so it likely needs to be bored .020 over at a minimum.
You can bring them the heads and they can recommend options for rebuilding / replacing.
Aluminum heads are a good option: 440 source Stealth, Edelbrock E-street etc...

 

[danf_fl]

How is the lifter area?

 

[That_1_71_Dodge]

What help are you looking for? You need to disassemble the block making sure to keep everything organized. You need to measure the bores to determine if they need to be bored or you can just hone them, more than likely you will need to bore it which will require new pistons.

Locate a local machine shop, hopefully someone you can work with. They will be able to tell you exactly what you need. Same issue with the heads, they will need at a minimum a clean up, lap the valves and new seals but more than likely they will need more than that such as seats, perhaps valves, etc.

There are lots of books/videos available on this issue.

Thank you, we are going to get those done and are taking the block up to get cleaned. We have it stripped to the block shown in the photo and everything organized. What I am wanting to know is what is a little bigger can I can put in the motor. I don’t want a race one but just a little bigger cam, I just don’t know what I should buy that’ll work.

 

[70chall440]

"what cam" is dependent on a lot of things, yes you can just buy something or take someone else's advice but it is best if you wait until you figure out what the engine is going to be, meaning will it be a larger displacement. Once you figure out that part and determine how you are going to use the engine (street, race, combo, fuel economy, low end torque, WOT performance, etc.) you can decide what intake and headers to use, this will help determine what cam along with what transmission, rear gears, and even tire size.

Point here is that IMO you are way too early to be worried about what cam to use. It is going to be very dependent on how many factors but once you get going down this road you should reach out to the various cam companies (Crane, Crower, Comp, Howard, etc.) and ask them what cam they recommend.

There are so many cam grinds/types that getting someone's opinion here is pretty much useless. That said, if you really want to focus on a cam just get the specs for the stock 383 magnum or a Mopar Purple cam.

 

[68-500]

On a stockish rebuild I would go with the 440 magnum, Roadrunner/Superbee cam. Melling makes a stock replacement.
I would aslo recommend pistons that are as close to zero deck that you can find.
If your heads are open chamber run a steel shim head gasket. If they are closed chamber regular head gasket that are around .040 thick.

 

[diesel_lv]

I would have to disagree w above statement that you are too early to be concerned w cam choice. My "opinion" is cam choice 1st, what is your intended desire. Cams operate in certain rpm ranges, require certain compression ratios, require certain lift clearances, springs, gear ratios, torque converters. Talk to a couple reputable cam companies and explain what you want, then build engine to match cam requirements. If you build engine 1st, you may be limited to cam that is more than what your desired outcome is.

 

[rickseeman]

You said you wanted a little more cam. Ok the old Mopar P4120235 or P5007697 (or something like that) would be good. That is a stock Street Hemi grind. .484" lift 241 duration. Simple, friendly and easy. If your heads need anything to speak of, and they probably will, I would buy new stealth heads. Rebuilding heads is expensive. New is cheap. I would call 440 Source or Hughes to help you thru this. Both are good wedge people with the exact knowledge you are looking for. Don't buy parts from Chevy people.

 

[wagonman]

Just my opinion but Stroke that 383. I think 440 Source can get you 490 something inches out of that 383.

 

[rickseeman]

Now that I think about it, I would buy my cam from Hughes because of their "no flat cam guarantee". I like that.

 

[Detective D]

If you can post the casting # off the heads people here can tell you if they are worth messing with. Basically you either want older heads with higher compression or the newest heads in good shape because the valve seats are hardened from the factory.
If you are on a budget, you can do some hand work with the heads and make them flow pretty decent, costs a lot of time and not much money. But they need to be usable first. Sunk valves= might as well buy new ones probably.
Post the numbers, inquiring minds want to know!