So I already searched btu I could not find the information I am looking for.
My older brother has a 350 block that has been machined/fluxed/bored 0.30 over and bagged for the last five years. Its a four bolt and I believe its a 70's block from a truck or RV or something.
Is there any difference in the 350 blocks from the 70's to 90's? (Excluding the LT1's Gen2)
So, I have to stay smog legal as I am in California and plus I like to do what I can to help the environment (I want to keep my smog equipment, modified? Maybe) I want to make sure everything from my 305 Will bolt up. (Excluding internals of course)

Also, My brother has a stock crankshaft for it he had micro polished, how much can a stock crank take before exploding?

My goals are 350-400 WHP on motor, smog legal (or at least undetectable) and maybe a 100 shot later down the road. I will of course used forged rods/pistons and possibly some aluminum heads.

 

Start your quest for knowledge by purchasing and reading a copy of "How to rebuild a Chevy small block"; http://www.amazon.com/How-Rebuild-Yo.../dp/1557880298 Covers the questions you have have now plus info you'll find handy later.

BTW, what's it going in?

Good luck

 

Its going into my 89 RS.
Here is a basic breakdown of what I have in mind:
Ported TPI system (Done by me)
Aluminum heads (Cheap ones, not vortech)
Hydraulic roller cam and lifters, roller rockers.
Forged pistons (looking for about 9.5:1)
Forged rods (Probably sportsmans or something, not looking to break 500)
micro polished stock 350 crank
350 block, .30 over. (So basically a 383)
Of course a well thought out intake I will probably fabricate myself.
Smog legal headers (maybe headman?)
True dual exhaust done by me, probably dual 2.5's with a 3.5 X pipe.
all the smog equipment off of the 305 I currently have.

I am not new to engine building, I have actually designed my own engine (A 2.6L 75degree flat plain v8 based on the Cosworth XB, Hayabusa and B18C5 ports... If you want to check it out I can send you an Edrwaings 3D file) I am a CAD expert...
All that being said I still don't know a whole bunch about the differences in 350 blocks. Thats why I am asking, I am fairly certain I don't need to read an entire book that tell me all sorts of things I already know. I just need to know if the blocks are the same
Thanks in advance,
Seth

 

Most 87 and newer sb's have a one piece rear main and provision for roller cam. Pre 87 are two piece rear mains and do not have provisions for OE style roller cam. Also, early sb's have drivers side dip. SB's came in either 2 or 4 bolt main, if that make a diff to you?

The pre-87 blocks will accept roller cams but, you'll spend more for the lifters. Will also require a cam button.

Sounds like you know your plan. Good luck with your project!

 

Thanks, I think I can live with that since I would be buying all new hardware for the cams anyhow. The conversion kits do look a little pricey (about $1000) for the cam, roller and links...
I might be better off with a newer block... I will have to contemplate this.
Thanks for you help,
Seth

 

Well, after looking over the block I have descided to bite... Its a four bolt 350 out of a truck, either a 3 or 76 according to the ID, what confuses me is the fact that it also has the H4 markings cast onto the rear of the block but the id is 3970010 which is either a 73 or 79 but there were no H4 blocks produced in 73 or 79?... Could this be a 73 still usin the 72 H4 code?

Anyway, the block is clean and I am going for a hydrolic flat tappet with roller rockers. The cost of the conversion kit is just was too rich for my blod and I think completely unnecicary.

He has this cam he is throwing in too, its a 292/302 http://store.summitracing.com/partde...7&autoview=sku
Not sure if I want to use this yet, looks like its for a blower/turbo... operating range 3000-6500? not so sure about all that nonsense.