68 dart with running 383 auto - advice to build another motor

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gdbuick

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Hello,
Father son project in the works. This is a running driving car now 383, 3000 stall so we are told, 391 rear gears mini tubbed. I know this is a loaded question with lots of directions but could we gather parts to build something around a 509 purple shaft cam or wilder idle on pump gas no concerns about vacuum we are manual disc breaks but on a budget? Piston choices seem to be limited without spending $1000.00 bucks alone on them. I assume with a big cam we will need notched pistons for valve clearance.
My son is 19 so I don't think we need a stroker build yet for him. I would rather work his way up in power levels but we both like a nasty idle. He has already bent a few push rods ha ha in the 383.

What I have is a 400 bare block and crank 73 ish
a 67 ish 383 block and crank
No pistons or rods for either.

Locally I have 452 or 906 heads for sale and possibly some closed chamber heads.
There are also a few 383 and 440's around.
Also a 361 1965 complete motor cheap- maybe take this for rods and crank for a 383 /400 build?

Looking for a recipe of major parts, compression and zero deck etc...
Build another motor on the side so we can keep driving.

thanks Greg
 
Last edited:
Sounds like you already have the parts “recipe”.

383 or 400, non-stroker, off the shelf pistons, iron heads, 509 cam.

The rest of the stuff is mostly personal preference.
What intake, carb, brands of gaskets, bearings, valvetrain, etc.
 
Early heads closed chamber heads will flow less unless ported, except "67" 915 440 heads. Use the later heads, 906 or 452 (hard exhaust seats).
 
Sounds like you already have the parts “recipe”.

383 or 400, non-stroker, off the shelf pistons, iron heads, 509 cam.

The rest of the stuff is mostly personal preference.
What intake, carb, brands of gaskets, bearings, valvetrain, etc.

Thanks for the reply,
What do people generally use for off the shelf pistons? I see KB forged or hypereutectic pistons ?
Not sure which iron heads I should pursue is why I was looking for some feedback as I have 3 different sets locally for sale or perhaps for my needs it doesn't matter so much.
 
Pistons and heads are going to be the biggest challenge. To upgrade the cast iron heads to larger valves and hardened seats you will have more money into them than just buying some closed chamber aluminum heads. 65'
 
KB hypers are a fine piston. We ran them for a few years in my son's 383. He abused the thing and the only thing that died were rod bearings. We sold all the 383 stuff after I found him a standard bore 400 block. He's got plans for a stroker...
 
KB hypers are a fine piston. We ran them for a few years in my son's 383. He abused the thing and the only thing that died were rod bearings. We sold all the 383 stuff after I found him a standard bore 400 block. He's got plans for a stroker...

That’s great to hear about the kB hypers. Reviewing heads I see the 440 source comes with bigger valves than the iron. Can I get away with freshening up some 452 used off a running 440 (I can buy a pair for 200.00) heads to run the 509 cam or am I just wasting money not going aluminum from the start. Fine line about throwing something together on a budget or spending up front I know not always easy. Just trying to avoid putting a lot of money in case my son gets a little over excited with the throttle. I blew up my share of engines when I was younger. He needs to earn the stroker..
 
No, you are good to go either way.
Thank you

I have seen several rebuilt 383 blocks with flat top pistons aftermarket for sale but no valve notches. Are people using this piston because they’re basically doing a stock rebuild? I don’t understand why they wouldn’t reuse the original pistons if good. My understanding with the flattop pistons without valve notches is you can’t run a more radical camshaft like the 509 I’m trying to do without valve notches.
 
Run the 452s just a 906 with hardened seats. Are you set on running the 509 cam? Tour going to need a good converter with it. The 284--484 would sound snotty and run fine with flat tops.
 
Stock 383 high comp pistons were flat tops. The KB hypers we ran in my son's 383 were domed and had valve reliefs. We ran a cam in the .490" 230 @ .050 range. I've got the .484/284 cam in my 440 and we're putting a Comp in my other son's 440 (actually already in the motor - yesterday) that is 274/286, .488/.491. Should run good. He's got a four speed with 3.23s, I've got a 727 with 3.55s. Not sure which I will like better. He's got more compression than I do.
 
Thank you

I have seen several rebuilt 383 blocks with flat top pistons aftermarket for sale but no valve notches. Are people using this piston because they’re basically doing a stock rebuild? I don’t understand why they wouldn’t reuse the original pistons if good. My understanding with the flattop pistons without valve notches is you can’t run a more radical camshaft like the 509 I’m trying to do without valve notches.
383 flat tops were 10:1 as I remember. I'd check piston to valve clearance with the 509 cam anyway.
 
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