New engine for the old girl

[custom442]

Just bought a chevy 350 bored .40 over (i think that makes it a 357?). It was rebuilt a few years ago and it's just sat since then. It's got surface rust down in the cylinder walls, but it can be cleaned. The seller said the heads were aluminum, but I'm not sure about that, they're pretty heavy 🙂. No crankshaft or timing chain, and the top end needs a some parts and work also.

So here's the question. Since now I have Christmas in my garage (although it isn't a 383 stroker), could someone suggest parts which would work well with an engine like this. Specifically parts for the upper engine and cam/timing stuff. Ideas on well, any parts you can think of. Intake ideas would help, but I have a good idea of that and the exhaust. Also, what is the best way to remove the rust inside the cylinder wells and inside the engine (and how to prime and oil the cylinders). Thanks, will post pics in the next few days.

I also bought a turbo 400, again, not the ideal 200r4 or 700r4, but good stuff anyways, will need to be rebuilt (engine and transmission were 400$, I thought I stole it when I drove off).

 

[megaladon6]

does it have pistons? if so, do you know what they are? (d-dish, flat top, dome, material--hypereutectic, aluminum, iron,) if it has them, but no crank, i'd be wary. that leads me to believe that he blew the crank which usually means there's other damage.
i'd pull the heads and look for casting numbers and identify them. one thing to do is flip them over and CAREFULLY measure how much fluid it takes to fill the combustion areas (to flat with the base). plus if they are painted, it won't be on the bottom which makes it real easy to see if it's aluminum. or you could just use a magnet. also measure the valve diameters.
if you need pistons, it has to go to the machine shop anyway. the cylinders have to be honed to match the pistons and ring material, that'll take care of the rust.
as to parts combo's, that's a personal thing. what do you plan on doing with it and what are your power goals? also, how much are you willing to spend? if you want a 383, now's the time, and they are only slightly more expensive than a 350. i'd spend the money for a roller cam conversion if it's a pre-80's block, it makes things so much simpler.

 

[custom442]

It has aluminum pistons, but not sure what type (how does one identify that?), the machine work on the cylinders has been finished. He just was waiting until he could afford the other parts, but never got around to it. Just to make sure, is there any way I could check for damage if it did blow a crank?

As for power goals I think above 300 hp to the rear wheels and closer to 400 tq would be nice, what do you recommed? (I could save up and buy new heads if I can't get the power out of the ones with it now)

Will post the number on the heads...

 

[custom442]

casting number on the heads is 3884520, date is B 17 7

So they're from a '67 with 60cc chambers (definitely not aluminum lol), should I upgrade them?

 

[megaladon6]

if the top of the piston is flat with maybe some small reliefs in it it's a flat top. if about 1/2-3/4 of the face is cut down to form a cup, that's a d-dish. and a dome piston has at least part of the face sticking up.
i'm not sure how to tell the difference between hypereutectic and aluminum. any chance he remembers the part number or manufacturer?

He just was waiting until he could afford the other parts

when you said it was rebuilt a few years ago i assumed it had been run and was now missing the crank. whoops! if you do want to check the block a machine shop should be able to magnaflux it.
sticking with a 350 and assuming a street driver, i'd go for 9.5-10:1 compression, a dual plane manifold, a 750cfm carb, and something like a 268xfi roller car.
that'll give you about 400HP at the flywheel.
you are going to have to figure out what the pistons are so you can figure out the compression ratio.
you definately need better heads. i'd probably use the 185cc runner vortecs as they are cheap and flow very well with 2.00I/1.55E valves. they have 66cc chambers and can take .530 lift.

 

[custom442]

Excellent, then the pistons are flat top, and they're for sure aluminum. The only identifying marks on them are ".40 over" and an arrow for alignment.

I would like to buy aluminum heads also, does someone make a kit for the whole valvetrain?

 

[megaladon6]

with 7cc flat tops and a 60cc head i'm getting 10.7 or so compression. of course most heads are 64+ so you may have problems finding the right one.

 

[custom442]

Ok, I'll clean up the stock ones and save some money. Could I run 10:1 compression with any problem you think? Thanks a ton.

 

[megaladon6]

well the 1960's tech sucks and you won't lose too much compression from the 4-6cc's, so i'd definatly upgrade. better heads are worth a lot of power.
you can run 11:1 compression on pump gas. even 12.5: has been done, but i wouldn't go that far. you do want higher compression with aluminum heads. probably 11:1. the patriot heads are supposed to be good. edelbrock e-tec are also good and i believe you can get them in a top end package

 

[v8power]

i do not know how much you budget is, but i recommend a whole top end kit, with cam, heads, intake,lifters, ect. i got the edelbrock one and am happy with it. you really have to be careful with any cylinder head you run to make sure the combustion chambers are actually the cc they claim. on the aluminum edelbrock heads all the chambers were off by 3.5 cc's which is allot. they claim it will be a certain compression, but when you do the math it will be allot lower than that. if i would have done it exactly the way edelbrock told me to, i would be just above 9:1 with that thick p.o.s. gasket they give you. i know allot of manufacturers make decent top end kits like dart and brodix. that is the way i went and everything goes together so smooth.