Building 69 383 for my 69 dart.

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SRT_DSTRHOLC

SRT_DSTRHOLC

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Well I will be picking up a 383 short block. It was a 2 barrel engine with low compression. I was wondering what some suggestions would be to get around 450-500hp.

If it was the 4 barrel I know I could follow 383 Engine Restore - Tech Articles - Mopar Muscle Magazine this, but not sure it will be easy to do with the actual compression being around 8.5 instead of 9.2-10.


Any suggestions? A nice cruiser with 11-12 second power is good
 
You are correct in your accessment of your 383 build . I have just finished mine and I am at about 420 h.p. with iron heads . I changed to forged 383 Magnum pistons for a little more c.r.. My h.p. to weight puts me in high 12's-low 13's . Your statement "A nice cruiser with 11-12 second power is good " is an ambitious goal that 8.5 c.r.. You need about 466 h.p. at the crank or about 375-380 at the tire . This goal can be achieved but it is not a budget build . I would be glad to help you achieve your goal if you wish . Later, Tom
 
IM interested in the pistons used or going to be used. Pistons for the 383 always seem to be an issue.
Spend big $$ on custom or is there something off the shelf that works.... in the 9-9.5 range?
Watching this thread :)
 
marksmopar1 said:
IM interested in the pistons used or going to be used. Pistons for the 383 always seem to be an issue.
Spend big $$ on custom or is there something off the shelf that works.... in the 9-9.5 range?
Watching this thread :)
Click to expand...
It's not hard to look at summit for pistons.... It's not a rare or awkward engine.
 
SRT_DSTR15 said:
It's not hard to look at summit for pistons.... It's not a rare or awkward engine.
Click to expand...

Here are my specs if it helps at all.

Bore - 4.280
Stroke 3.38
Rod length 6.358
Gasket bore 4.40
Block deck height 9.960 (stock=9.980) Took .020 off
HG thickness - .039 (Felpro)
Piston to deck height - .000 to .005
Piston volume - (-6) (KB400 .030 dome pistons)
Chamber size – 84cc (I'm using sidewinders from Mopartsracing.com *Todd*)
Total comp = 10.01:1
Comp Dual valve springs (925-16)
Comp retainers (741-16)
Comp super locks (611-16)
Comp Cam XE274H part number 21-224-4
Intake 274/488- Exhaust 286/491

Additional specs:
Weiand Action plus intake
MSD Pro-Billet Distributor with blaster 2 coil
Pro systems Holley pro series 4150 carb
Holley blue fuel pump (7psi)
440 source aluminum water pump (160 thermostat )
3400 Dynamic converter (Frank Lupo)
30” rear tires M/T
Dana 60 3:55 gears
Truck weight 3650#

Tuning Sharadon Performance (70 primary jets)- (13 initial timing, 34 all in at 2800rpm)

451hp Engine Dyno (open headers)

420hp through full exhaust (started at 346)

364hp at rear wheels (started at 301)

364 rear wheel hp= 451 crank HP
 
x2 /Schmitt . Sealed Power/TRW has a forged piston, which I used, and it is for 1968,383 Magnum . I'm not sure but I think 1969 383 Magnum piston is the same part . 1970 is a little lower in c.r. but the gram weights are the same . This piston is legal for NHRA stock Eliminator . However I used this piston with a "915" head @ 78.5 cc with a factory head gasket @ .022" thickness gives me a pump gas friendly 9.6: 1 c.r.. The closed chamber heads provide a quench area to help combat detonation . This won't get me in the low 12's . Eddy heads and intake might just do it , though . Later, Tom
 
SRT_DSTR15 said:
It's not hard to look at summit for pistons.... It's not a rare or awkward engine.
Click to expand...

Yes correct it is not a rare or awkward engine, but piston choices are not as plentiful as the other mopar engines
I want a real 9.5 not 8 CR.... doing the math on some of these, they are not what they should be. Piston selection for 383 is well known as not so good. So I am curious as to what people are using
 
383Scampman said:
x2 /Schmitt . Sealed Power/TRW has a forged piston, which I used, and it is for 1968,383 Magnum . I'm not sure but I think 1969 383 Magnum piston is the same part . 1970 is a little lower in c.r. but the gram weights are the same . This piston is legal for NHRA stock Eliminator . However I used this piston with a "915" head @ 78.5 cc with a factory head gasket @ .022" thickness gives me a pump gas friendly 9.6: 1 c.r.. The closed chamber heads provide a quench area to help combat detonation . This won't get me in the low 12's . Eddy heads and intake might just do it , though . Later, Tom
Click to expand...

Yes, It seems close chamber heads are needed to get that 9.5 out of most of the available pistons. If a 906 head with 88cc is used it's down to 8-8.5 with the same piston...thus the issue.. Oh and I am not looking at cutting the deck down. IM watching :) great thread..I dont want to hijack it with my question. Let see what this build yields
 
Thoughts on this build? Lot of power for low compression

image.png
 
69 dart with 383 from factory weighs 3200. So 400 wheel should be more than enough. I'm thinking maybe stock engine with low compression, turbo roller cam and supercharger
 
SRT_DSTR15 said:
69 dart with 383 from factory weighs 3200. So 400 wheel should be more than enough. I'm thinking maybe stock engine with low compression, turbo roller cam and supercharger
Click to expand...

Very nice power, the supercharger help....a lot! The supercharger would need a lower compression im thinking....otherwise blown pistons, ring lands, head gaskets...nice set up!
I am wanting to build power with a stock looking motor, naturally aspirated. Nice build you have there!
 
I have the combo you're looking for -

0 deck block
stock crank
stock rods w/ ARP bolts
KB 5cc dome pistons (11:1 static)
cam of your choice (I have a tiny Comp 280H)
roller rockers (I have Crane 1.6's)
Stealth heads - ported, Comp springs, milled flat
unported Edelbrock Performer RPM
1/2" 4 hole spacer
750 QFT carb
under drive crank pulley
2" headers
3" exhaust

Made 460hp/450ft lb under 6,000rpm. boils drag radials, and is a TON of fun - guy that owned the dyno said with a better cam in the .580"-.650" lift range it would make over 500hp

demon%20210_zps3so8ts7q.jpg
 
SRT_DSTR15 said:
Thoughts on this build? Lot of power for low compression

View attachment 1715020347
Click to expand...
I forgot about that piece of crap. It had so much blow-by that we used two pieces of 5/8" hose about 2'-6" long on the valve cover breathers and they would stand straight out horizontal at rpm. Wiped out a couple of lobes on the Hughes cam. Put an old roller cam in it and it made 525 HP. Put a hydraulic flat tappet in it and used it as a mule the first time we set up our new-to-us 901 Super Flow engine dyno. The engine still sets over in the corner under a tarp.
 
Oh that's yours?! Dang haha well I'd like to copy it lol but maybe redo the rings and stuff
IQ52 said:
I forgot about that piece of crap. It had so much blow-by that we used two pieces of 5/8" hose about 2'-6" long on the valve cover breathers and they would stand straight out horizontal at rpm. Wiped out a couple of lobes on the Hughes cam. Put an old roller cam in it and it made 525 HP. Put a hydraulic flat tappet in it and used it as a mule the first time we set up our new-to-us 901 Super Flow engine dyno. The engine still sets over in the corner under a tarp.
Click to expand...
 
If you want stock look and those power figures, you'll need more than 383". I would suggest a stroker package. A 496 with Stealths or well-ported factory iron will reach those numbers easily, and be able to run the number looking stock. You can search this forum for 496 builds.
 
moper said:
If you want stock look and those power figures, you'll need more than 383". I would suggest a stroker package. A 496 with Stealths or well-ported factory iron will reach those numbers easily, and be able to run the number looking stock. You can search this forum for 496 builds.
Click to expand...
That's what I'm starting to think without a SC. Might be a waste of time to go to 383 and be slightly bigger than 360. Might as well throw a 440 in
 
Do you guys think it's even worth building a 383? They are barely bigger than a 360. Seems like if it's not a 440 short block, might as well not go BB. What do you all think?
 
For me the car was an original 383 so that is what I want to build.....just looking for a stock look with reasonable cost and hidden performance. This is not a race car and original exhaust manifolds will be used I will go to an aluminum intake dual plane and aluminum water pump (painting all original engine color) loosing some weight. so no sense in considering huge cams etc, just a good performer to cruise
 
SRT_DSTR15 said:
Do you guys think it's even worth building a 383? They are barely bigger than a 360. Seems like if it's not a 440 short block, might as well not go BB. What do you all think?
Click to expand...

Depends on your budget. Cool thing with 383 is you can mildly stroke it (431ish final CI with .030 bore with 3.75 stroke if memory serves) and stroke:bore ratio is still such that you can rev crap out of it and it will pull like a monster.

Several places sell kits / cranks so no need ol school reqt of modifying 440 crank.

Not a "budget" build .. but not outrageous either.
 
I just built a 383 for my '67 383 Formula S. I found to rebuild the closed chamber heads I had with new valves/springs/retainers/ex. seats, it was going to be marginally less expensive than getting new Edelbrock heads. For just a couple hundred bucks more you get a lot more performance.
 
Deucemopar said:
Depends on your budget. Cool thing with 383 is you can mildly stroke it (431ish final CI with .030 bore with 3.75 stroke if memory serves) and stroke:bore ratio is still such that you can rev crap out of it and it will pull like a monster.

Several places sell kits / cranks so no need ol school reqt of modifying 440 crank.

Not a "budget" build .. but not outrageous either.
Click to expand...
Still marginally better than a SB 410 stroker. My point is, is it worth it to go BB if you aren't going 440?
 
If I didn't have a 383 car I would have just bought a Blue Point Crate Motor. I think you can get a 408 stroker that makes 375hp/460tq for right around $4,200.
 
heads 1st, no matter which cubic inch you decide on. it's gonna take a GOOD flowing head to make 450-500 horse.
bigger cubes will make hp and torque at a lower rpm and live. BUT, you still need the cfm to feed it.
 
GRANCUDA said:
I just built a 383 for my '67 383 Formula S. I found to rebuild the closed chamber heads I had with new valves/springs/retainers/ex. seats, it was going to be marginally less expensive than getting new Edelbrock heads. For just a couple hundred bucks more you get a lot more performance.
Click to expand...

You are correct, I am using 440 Source stealth heads...painted engine color, alum intake and water pump...Stealth is the idea ;) Had these heads on a 400 stroker for a few years no issues, great set of heads
 
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