Need advice 383 build

[mopar350]

I am looking into building a 383. trans will be a a518 od non lockup rear gear options are 3.55,391 or 4.10's and 28-28.5" dia tires.

Now for the engine the crank will be the stock forged piece 3.375 stroke. Should i use the 440 lenght rod in the build and Diamonds piston 51907 or the stock 383 lenght rod and piston 51900? I am looking for a 9.5-10:1 cr as well. the cam i am looking at is Xtreme Energy™ XE250H; 600-4800 RPM Range. and as far as heads go do i spend money on Haveing the cast iron 516's 906's or 452's or trick flow or e-street? I am looking at the Edelbrock Performer RPM intake manifold 7139 and a Thermo-Quad, 800 cfm carb. I am looking for low end torque and a crusie speed of 1800-2100rpm 70-75mph.
Just so you know It will be going in a 89D150 and i have 67 383 in my 87D150 I get 11-13mpg to work and back 130 miles round trip 727trans 3.21 gears and 29"dia tires. 15-16mpg if i can keep the rpms below 2500rpm. I did look into building a 318 but just can't do it got to have my BB.

 

[1967coronet440]

Only thing I will say is if you can afford the trick flows get them.

 

[dieseldazzle]

I went down this same path in a factory 383 4 barrel 67 charger we had that Burnt a valve.

I ended up with 438 inch 6.760 rod 3.75 striker kit from 440 source. Used the stock 516 heads with 1.74 exhaust valves. Purple shaft 455 cam.

After factoring in new pistons, resized rods, new rings new bearings, turned crank and then balancing it all... for 600 bucks more I had a nicer piston (1/16 ring pack) better rod (h beam with arp2000 rodbolts) and balanced.

Now the motor it's not a powerhouse with the stock intake, carb and exhaust manifolds but it runs really really smooth. Idles nice and feels about like a stock 440 magnum does.

 

[Superb Bee]

383 is an amazing motor, I have built many, I actually have one in a 70 2 wd d100 (original dude truck) 727.

I would use the stock rods, if your rods are good use them, the best part about building a 383 is low cost, so keep it that way.

the heads really depend on what it will cost you to get the ci heads reconditioned.
I would personally grab a set of 906s off the shelf, have new valves, springs to match your cam, etc installed
valves are $90, Springs are $60, labor for the heads to be cleaned, port matched, valve jobbed, and assembled $275ish, you should be into a set for under $500 and they are nice heads.

The next option in my book would be source 440 aluminum heads, about double the price of doing the ci heads.


As far as the build goes, they are easy, I did the motor in my d100 with 906 heads, elgin brand "RV" cam ($99 with lifters), sealed power flat tops .030 with rings $250, proform distributor kit $130, Fi tech fuel injection kit $800, I was into it for $1800 with labor and everything fluids and all, used an edlebrock torker intake, and that truck screams, runs like a top, sounds great, idles great, and PULLS like a freight train, I used it to tow the 20 enclosed hauler from RI to virginia kentucky tennessee line, not a hiccup, up some steep inclines and you would have thought it was a diesel if it wasn't so quiet. Plus that truck will smoke tire 100 feet into second gear, thats fun too.

 

[mopar 3 B]

Something's wrong with this picture? Why aren't you getting 15 to 16 mpg now? You need to evaluate what you have.

 

[AMX364]

Silly me, I thought that the a518 only fit the small block at this time. Has that changed?
edit: With the Ultra bell bellhousing #92457 it will fit a big block.

 

[mopar350]

thanks for the advice so far much appreciated!

why am i not getting 15-16 now 8-10miles city traffic 20-23 miles 2 lane back road and no one can seam to keep a steady speed on the straight aways they do 65 but can not take a slight curve in the road with out slowing to 40 mph limit is 55mph. 27 miles give or take on highway 70mph limit every one runs 75-80 so the rpms are up 2700-3000. the 800mile trip from sc to ny i was able to cruise along 60-65 average at 2200-2400rpm nonstop 12hrs straight.

518 to bb mopar adapter with out cutting 518 bell off the 518 your going to use.

https://transmissioncenter.net/shop...ge-small-block-518-transmission-6-bolt-crank/

 

[mopar 3 B]

You can add the overdrive but really doubt it solves the problem.

 

[66Satellite47]

I doubt the longer rod gets you anything you'd notice. I'd also go a step or two up in the cam. Heads, for what you're doing is a toss up. 906, 452, 516(w/2.08/1.74 valves) will work fine. Do a little pocket porting & get big improvement in torque & power. Aftermarket heads if the pocketbook allows. Good luck with the Thermo-Quad. Do the math & figure the actual CR & adjust with head gaskets or head milling. 9.5 should still work with pump gas & careful timing adjustment.

 

[mopar350]

I finally found a good site that explains what a long rod ratio would do. figure others may want to check it out.
http://victorylibrary.com/mopar/rod-tech-c.htm

looks like i will have to have custom pistons any way i go about it or at least the pin location changed. if i am doing the math right.

 

[71SandbugCharger]

Excellent!!! All of it! Now, to put away the popcorn and get the interior done so I can focus on my 383! Don't forget to upgrade the driveshaft!

 

[lewtot184]

rb rods will be too long for any low end grunt. the rod ratio would 2:1; use the stock rods. multiply the overdrive ratio by the rear end ratio to get the final drive ratio; then do the math on the final drive and tire circumference to know what the cruise rpm would be for that rear gear.

 

[mopar350]

If things go well I will be ordering costum pistons from Ross Pistons next thur's day or friday based off of there 99894 383 Stoker design comp. height will be 1.928 which will leave the piston .0065 below the deck combined with a .030 thick head gasket leaves .0365 the minimum piston to head distance for close chamber heads. Wrist pin diameter of 1.094 for use with stock rods (press or floating I hope).
If any one has ideas on this i have not thought of or advice let me know before wed. 4/19/17.

 

[66Satellite47]

Ross pistons were good for me years ago. Looking at the compression calculator be sure to figure the minus volume of the valve notches. Likely in the 4 -6 cc range, Ross can tell you that. With stock rods get them shot peened & use good ARP rod bolts. Which heads will you use? Old 906, 915 or 452 iron heads can make good power with a mild pocket port. Check with the engine builder about CR with pump gas. Seems like 9.5 with iron heads is OK, 10.5 works fine with EDE RPM Performers and pump premium. Good luck.

 

[mopar350]

Any material removed for valve relief's i will have add back even if it makes a dome. hoping we can come up with a configuration that will work with any factory cast head and most of the after market heads. I will also include the .5cc area around the piston and cylinder wall from the first compression ring to top of piston.
think I will be going with eagle rods.

 

[66Satellite47]

Just plug in the valve notch cc into the calculator. Decide if you are going stock style iron head or aluminum, makes a big difference in what CR you want.