Thread: 350 sb head questions

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well im giving some thought on selling my 400sb. its not really what i wanted to began with.
ive got a 350 i did some swapping with my dad and i know it runs. when we got it out of a wrecked 79 gmc longbed. the engine still had a builders tag on it from a local engine wholesale outfit. marked about 6 months before the truck was wrecked. took the heads off the motor and its been bored .40 from the stamping on the pistons. i do not recall what type of pistons are in it. i think they got some kind of vavle relif in the top ill have to check again.

after doing some reading in couple of books and seeing some article in some magizines. i seen some stroker builds using RPO L31 vortec heads. and also found some info bout them beeing a good mild performance street head.
ive thought about trying ot get a set of them and putting on the 350 i have. and maybe using a lunati cam this one here
Voodoo Hyd Cam - Chevrolet Small Block 268/276 - Lunati Power

i know i would have to change the springs in the heads which is no big deal.
then maybe even going with some keith black pistons .40 over an good intake and carb. looking for a damn good street build engine that i can eat some mustangs. the motor will be going into 82 chevy swb with turbo 350 transmission.
some ideas and tips and thoughts are welcome

one of thease days i plan on having a superchaged 383 stroker but thats way in the future

Here is a list of engine combos worth reading about:

Ryan's Small Block Chevy Stroker Engine Combo Page

Use the 400-----

im selling the 400 using it is not an option the 400 is not what i want.

So you talk about a stroker twice---and that you don't want the 400---do you realize that the 383 are a 350 block with a 400 stroke???? or that the 400 has a bigger 4.125 bore compared to the 350 having a 4.000 bore???
We build probably 60 sbc a year and the stock car racers love the 400s, and we sell a huge number of the Dart SHP blocks(4.125 bore 350 main size) world wide(well so far none to Africa)
We also do a lot of installing angle bolted billet main caps on the LT blocks, but pretty much use the SHP blocks for the others

yes i do realize that 350 uses the 400 crank also have to have the 400 flex plate and balancer

there are reasons i do not want the 400 block for one its bored .60 over
another reason to many people have had there hands in it and been messing with it.

so this would have been a different subject if you had not typed the first line of your post???

Ok, .060 is about it for a 400 because thats 4.185 and the head gaskets out there are at aprox 4.200 bore size--
can really understand the issue of too many people have had there hands in it---

When you get ready to do the supercharged engine give the Dart SHP a look see---

apparently people have missed the question where i asked about the vortec heads.
working on the 350 thats been bored 40 over that i have aqquired.

we have only built ONE engine in the last 10 years that used the Vortec heads--he , like you, had read some articles about them---well it takes a spring change(which I seem to remember having to cut for the spring base) different studs, guide plates, etc, and then bigger valves which took some pocket porting, and different intake manifold (think there was issue of drilling tapping for center bolts) and maybe even different headers because the exhaust ports were different---

Probably plenty of cam for an automatic in a pickup--get the right stall converter it should work. Might want to check over that 'rebuilt' short block....some rebuilders don't use the best components in them, for sure it's just a set of cast pistons. You'll have to check the bore to see how crazy the shop got on the honing and how big the bore is now, piston to wall clearance is going to be different with a hypereautectic or a forged piston so you'd want to make sure the cylinders aren't too big already.

Don't know much about the Vortec heads, I know of a few local guys running them that seem to make decent power. What gears do you have in the rear end of the pickup? Doesn't do much good to have an engine built with some decent power then having it going to some lazy highway geared rearend so you might want to check that, too.

now i had noticed summit and jegs have a set of vortec style heads. GM Performance 25534351 - GM Performance Vortec Small Port Bowtie Cylinder Heads - Overview - SummitRacing.com

the fine print at the bottom says 0.530 inch cam lift and can use the older style intake also. or a vortec style intake
i dont plan on using a cam with a 530 inch lift just the cam i posted in the first orig post or something like it
then maybe some better pistons good intake and carb

dave ive got the correct stall convertor it requires 2400 stall and thats what i have.
the gears in hte truck are 4.11s and its a one tire fryer i thought maybe some 3.73 posi trck?

so its your plan to change pistons on the 350 you have thats 040 over already??Are you going to hone it for fresh rings on the new pistons??rebalance it after you have the pistons pressed off the old rods??recondition the rods big end?? new rod bolts?? align hone mains?? is the rebuilt tank show undersized crank??

i dont even know what type of pistons or what brand that were used.
i can tell its 40 over because of the stamping on the pistons
and they have some type of vavle relief
if it was required to change them yes i did hear the motor run sounded like it had a mild cam in it maybe an rv cam
as of right now the 350 is short blocked
when pulling hte oil pan off there were no shavings in the pan
iven ot takin any rods lose to see if crank has been turned

well if you got the pan off pull a rod and a main to check the bearing?crank size--lots of rebuilders markings will include either a code or the actual sizes