383 connecting rods

[slyhog2007]

Ive recently started buying parts for my 383 build and just have a few questions. Ive been told that all 383 cranks are forged, and so are the rods. Is this correct?? also im using a set of KB 400 pistons with 906 head and aiming for 9.5-10:1 CR, doable??? also how strong are the crank and rod of the 383???

 

[IQ52]

Nope, not all 383 cranks are forged. The 383 2bbl engine in 1971 used a cast crank. They all had forged rods. The stock forged crank and rods have been used repeatedly to over 7000 rpm. I would recommend you replace the stock rod bolts and resize the rods.

906 head, KB400 piston, 9.5-10:1, doable? If by that you mean, "Is it physically possible?" Yes. A 4.280" bore, 90cc head, zero deck, .040" head gasket will get you 9.5:1.

 

[slyhog2007]

i have a 68 2 bbl checked the casting number today and according to what i found i have a forged crank as well casting number:2206159.

 

[demon seed]

2206159 is forged.

 

[slyhog2007]

so if all 383 rods are forged then i can save 458 on rods, casting on my rods is 1737692, with 488 on cap, these should be forged as well, correct? Have that go towards other things needed. Thanks guys. I've been looking at cams; has anyone had any good experience with Howards cams???? I'm looking at using the Howards Cams CL721201-08. Hydraulic Flat Tappet, Advertised Duration 285/289, Lift .555/.562. 2800-6600 rpm range. I'm looking for a decent 1/8 mile or bracket car.

 

[JohnRR]

906 head, KB400 piston, 9.5-10:1, doable? If by that you mean, "Is it physically possible?" Yes. A 4.280" bore, 90cc head, zero deck, .040" head gasket will get you 9.5:1.

I hate the hyperuthetic pistons, they do NOT like to be put into detonation.

A flat top, 5cc reliefs , .010 in the hole ... you need to have the block trimmed about .015 , it needs to be squared anyway... .021 steel shim gaskets and the heads cut to 80 cc will net you 9.48 and you'll have to run 93 because you head choice isn't good with that open chamber head.

 

[IQ52]

I hate the hyperuthetic pistons, they do NOT like to be put into detonation.

A flat top, 5cc reliefs , .010 in the hole ... you need to have the block trimmed about .015 , it needs to be squared anyway... .021 steel shim gaskets and the heads cut to 80 cc will net you 9.48 and you'll have to run 93 because you head choice isn't good with that open chamber head.

Have it yer way. But I'm thinkin' the Chrysler 383 KB400 is a domed piston with a -6cc value! The Chrysler 400 KB240 has +5cc valve reliefs.