Keep my 383 and stroke it?

[Yellow Submarine]

I'm looking down the road a little but want to get an idea which direction to go. My car is a 70' RT SE Challenger that I want to look very stock but be able to fry the tires at will. The previous owner had done some mechanical work including a completely rebuilt (have receipts) low compression (low comp pistons)  383. It is not the origional block but is correct year. I'm thinking of going one of two ways. One is to buy a stroked 440 and the other is use my block and valve train building a 496. I would need to check my bores first but I am pretty sure it has no miles other than what I have put on it which is about 200. The thought being just have the bores honed and go with whatever overbore I have. Use Stealth heads, mild cam, RPM intake, 760 Holley and good headers. Looking for about 500 tq and 500hp. Does this make sense or should I get a 440 striker which would cost more.
Any thoughts are appreciated.
John

[turbostang7]

I think cost would be a wash for parts. the 440 would cost more if you don't already have a machined block (you would have to procure one of those and get the machining done)

[Chryco Psycho]

both will work fine , as above cost will be similar parts wise , the 383 block will look more original , I would go 436 or 470 CI with the 383 block  496 in a 383 block is more of a race build not a street engine , with a 440 I would go to 512 ci , or with a 400 block you can do 451 ci

[rUNCHARGER]

It's not the original block anyway so I would buy a 400 block and build a low deck stroker with it. The 4.25 bore 383 block shrouds the valves when you are building power. In my mind it is the original block to the car or it isn't.

Sheldon

[Yellow Submarine]

Cryco

Why the smaller displacement?
Reasons for using my existing 383 are I have all the water pump, front cover, distributed, brackets for everything, lighter than 440 and has already been machined. Any other block and all this goes out the window and I pay for new stuff. Block number does not matter much to me. Having the car look stock does.
All other things equal I think a different block would cost me a couple grand with machining and RB specific parts. As I understand 383s don't bring much$.

John

[Chryco Psycho]

the 383 / 434 CI is a 440 with a smaller bore , same rod ratio & you take 7 lbs off the rotating mass so it revs fast but will live with the 1.8 rod ratio , I have built a number of these , basically an improved 440 .
 The 383 / 496 CI ends up with a 1.6 rod ratio which side loads the piston a lot more + now you have a very short piston to the point where you have to press in the piston pin then install the oil ring over the piston pin , this can lead to shorter piston & ring life as the piston can rock more in the bore as the piston is so short & increased oil consumption with the oil ring that low or the piston pin that high up .
 The stealth head & mild cam will probably not flow enough for 500 ci either .
 SO to me the 496 is more of a short life race build while the 434 will make a ton of power & be a better street build .

[Yellow Submarine]

Thanks CP. I am familiar with similar shortcomings on SBFs with certain rod lengths causing similar problems. I'm guessing the 438 is adequately fed by the stealth heads but has good torque. That is really what I am looking for. I want this car to be a comfortable stock looking driver that can hold its own.

John

[Chryco Psycho]

Then I would stay with the lower CI  434 / 470 & build a quick revving torque monster

[todd383]

Well I have a 383 496 kit from muscle motors,  it has 440 sorce aluminum heads, ported, comp solid cam, 10.5 to 1 comp ported rpm intake and 950 holley street hp carb,  590 hp and 615 tq.  All I can say is I beat the crap out of it, lots of chassis dyno time,  many burnouts and over revving the engine, lol, and a few trips down the drag stip, and many out of state Road trips, I gotta say I put almost 18000 hard miles on it, and never ever had a problem with it. I would definitely do another one.

[barnett468]

nothing really "wrong" with 1.6 rod ratio, in fact many ford strokers are running 1.52 and last many miles . the key is building it properly and using high quality oil . did i say high quality oil? yup.

i would also use 4032 material pistons instead of 2618 . srp, mahle and race tech are all good.

[Road_Runner]

So I'm going down the same path with the original 383 in my Roadrunner and I'm still trying to decide which size to go with myself.  I'm leaning heavily towards the 450 c.i. kit Muscle Motors sells as a good middle of the road choice.  It uses a long rod similar to the 431 stroker which Chryco recommends so strongly.  My HP & TQ targets are 500-550+ while still being civil on the street.  I've already got a set of CNC ported Stealth heads and original NOS Mopar Performance six pack setup so far so whatever I pick it has to work with those parts.  I will say I haven't totally ruled out just keeping it a 383 with the above parts.  It was plenty fast when I was a kid with the original heads which ought to add 50-75? HP along with a modern cam, etc.  Check out the Muscle Motors 450 kit, might be just the ticket for what you're looking for.

Later, Jim

[barnett468]

musclemotors 450 kit as mentioned above . it is near the bottom of the page.

http://www.musclemotorsracing.com/new-page/

yeah, i too think this is a very good combo, however, if you need dished pistons, i would use custom made pistons and have the dome machined to mirror the quench pad on the head . race tech will sell you custom pistons in 4032 material for only $575.00.

use a roller cam.