..need some help 350 with vortec heads

[regan56]

Thanks for the lesson on the vortec heads..forums like this are a real great place for knowledge. I have since decided to stick with my 327 and get it bored as well as get the crank looked at and ready to put back in.

I will be looking for a set of vortec heads that are in decent shape and a new intake to match that I can add a carb on top.

Will any set of vortec heads from a donor engine work on my block? Does it have to be a spefic band of years?

[1project2many]

Any year Vortec heads work. 305's have smaller combustion chambers and valves than 350s. 1996 was the first production year and they were used as late as 2002 in vans. One ton vehicles have slightly larger valve stems and valve seat inserts which may be a little more durable but hurt flow ever so slightly. The fastest way to ID Vortecs is by the intake bolts. Vortecs use four 5/16" bolts per head instead of six 3/8" bolts. There are no intake manifold bolt holes in the center of Vortec heads.

There are several different intakes available. Have you decided on the carb yet? Spread bore like a Quadrajet or square bore like a Holley / AFB?

[regan56]

Originally Posted by 1project2many

Any year Vortec heads work. 305's have smaller combustion chambers and valves than 350s. 1996 was the first production year and they were used as late as 2002 in vans. One ton vehicles have slightly larger valve stems and valve seat inserts which may be a little more durable but hurt flow ever so slightly. The fastest way to ID Vortecs is by the intake bolts. Vortecs use four 5/16" bolts per head instead of six 3/8" bolts. There are no intake manifold bolt holes in the center of Vortec heads.

There are several different intakes available. Have you decided on the carb yet? Spread bore like a Quadrajet or square bore like a Holley / AFB?

Thanks for this...no I haven't decided on a carb yet..I suppose that is part of the intake selection as well...

[Marshy]

Dont take this this wrong way but, do your homeowrk on the vortec heads. Lots of great info out there on them and which to use in the older gen I blocks. I'll throw ya a bone and say your should be looking for casting numbers that end in 906 and 062. Im not being a D***, I didnt know general stuff about 350's let alone details about vortec heads so I spend about 2 weeks reading all the info I could about 350's and vortec heads. Now I can tell a 906 vs an 062 head just by the casting marks on the front of the head. I know how much lift they are good to in stock form and what it takes to get them preped for high lift application. I know how much better they flow vs the old school heads and what the combustion chamber looks like and why they are so efficient.
I just took off a set of old 305 heads someone put on my truck and will be putting on some 062's. Use google search and build your knowledge, dont take someones word for it (I'm not saying anyone is feeding you BS), be your own expert.

[regan56]

Originally Posted by Marshy

Dont take this this wrong way but, do your homeowrk on the vortec heads. Lots of great info out there on them and which to use in the older gen I blocks. I'll throw ya a bone and say your should be looking for casting numbers that end in 906 and 062. Im not being a D***, I didnt know general stuff about 350's let alone details about vortec heads so I spend about 2 weeks reading all the info I could about 350's and vortec heads. Now I can tell a 906 vs an 062 head just by the casting marks on the front of the head. I know how much lift they are good to in stock form and what it takes to get them preped for high lift application. I know how much better they flow vs the old school heads and what the combustion chamber looks like and why they are so efficient.
I just took off a set of old 305 heads someone put on my truck and will be putting on some 062's. Use google search and build your knowledge, dont take someones word for it (I'm not saying anyone is feeding you BS), be your own expert.

ya..thanks for teh info.

i have decided to look around at the vortec or maybe even just stick with a std head and intake setup. i mean i really dont need to race this thing, i just want to be able to drive it around with confidence.

[1project2many]

Vortec heads are good for a daily driver. If an engine with these heads shows up at a good price, don't be afraid to grab it.

[Marshy]

These heads are great for a daily driver, after all that's what they were made for. I bought a pair at my junk yard for $75 and have a $15 core per head I still need to collect. It will cost me te same $300-$350 for my machinist to refresh them vs the 305 heads that came off my engine. I expect will make a noticeable improvement over the old heads but will be hard to tell exactly how much after I add headers and a cam.

[dubds10]

Around here in BC you can buy a short block ready to go $1800 so the pricing you got is right in our market. Machining is typically $1000 or so for a block here. Or $800USD, not often cheaper unless you're going to a chesp guy who's not as good. Alum heads $700-1000 complete new, intake & carb will be $600 at least. So $3500 is typical for a new basic 350 but better than a stocker. You can piece one together yourself with used parts for cheaper of course or go all new & not worry about it.

Skip that in pieces 350 of course. I skip anything that has rust & only look at fresh builds with paperwork or complete runners when I'm interested in engines. You can find stock runners for $500 all day long that may just need freshened up with gaskets & that's it. You can usually find HP runners 327, 355, 383 for less than you can build them also if you look hard or look at cars being parted out.

[Marshy]

Alright, got some measurements to share after pulling the block and getting it on the stand.
Deck Height = 0.048"
Piston dish depth = 0.030"
Approx dish diameter = 3.150"

I'm going to pop these # in a CR calculator later and see what my approximate CR is with 64cc heads. Only thing I dont know is how thick the head gasket typically is... Is 0.020" a good number to use?
I'm strongly considering sending the block to my machinist to have him disassemble and hot tank. The damn thing is a dirty mess and the cylinder bores have some slight surface corrosion from the coolant getting in them (I have pics). I've also been tossing around the idea of installing some flat top pistons. I will run the CR calculator with a flat top installed and see what I get. Hope everyone had a happy Independence Day.

[Marshy]

Oops, I just realized I put this in the wrong thread. Sorry for the above post.