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Why shouldnt I build this 350?

2K views 17 replies 8 participants last post by  Smackmatic 
#1 ·
I have a "free" sbc 350 in my garage. It is a 79 block, was running and is in good condition. I want to retain the stock bottom end and pistons. Install EQ vortec heads, and reuse the valves that are in the engine now (1.94/1.50), with comp behive springs. I want to have the heads milled down to get the compresion as close to 10:1 as possible. I will use a comp xe284h cam. I havent decided on an intake yet, but I will probally use a holley 750 carb. I have an edelbrock 600cfm carb, but I am afraid that carb will hurt hp with this setup.

This will go into my 67 c-10 shortbed with a saginaw 4-speed and 3:73 gears.

I would like the truck to be quicker than a 73 camaro with a zz4 crate motor, turbo 350 trans and 3:73 gears.

Is this a waste of my time and money?
 
#2 ·
Smackmatic said:
I have a "free" sbc 350 in my garage. It is a 79 block, was running and is in good condition. I want to retain the stock bottom end and pistons. Install EQ vortec heads, and reuse the valves that are in the engine now (1.94/1.50), with comp behive springs. I want to have the heads milled down to get the compresion as close to 10:1 as possible. I will use a comp xe284h cam. I havent decided on an intake yet, but I will probally use a holley 750 carb. I have an edelbrock 600cfm carb, but I am afraid that carb will hurt hp with this setup.

This will go into my 67 c-10 shortbed with a saginaw 4-speed and 3:73 gears.

I would like the truck to be quicker than a 73 camaro with a zz4 crate motor, turbo 350 trans and 3:73 gears.

Is this a waste of my time and money?
Your engine is only as good as the foundation you build it on.

The piston/bore wear as well as the oil clearances at the crank & rod bearings needs to be assessed to see if the engine needs a fresh set of pistons and/or a ground crank/fresh bearings before you go w/all the go-fast goodies.

The oil pump has probably seen better days, the timing set is likely well worn, gaskets will be weepy, etc.

Any engine that is going to be used in a high performance vehicle needs to have all its bases covered. Otherwise you could be building a short-fused engine that won't ever live up to its potential.
 
#3 ·
I recently made a trade in order to get a 1990 4.3 V6 block. I asked my brother in law who owned it, how long did it have before it grenaded. He said it ran good and thought it would be fine. I knew better, My nephew ran the engine in his daily driver blazer and he was really hard on it. I knew when I got it I was going to rebuild it before doing anything else with it. I tore it down and found all 6 compression rings broken and 3 cracked pistons. My nephew called me and I said "when did you drown this engine?" and he said "How did you know about that?" and I said "all 6 compression rings are broke, usually when a engine swallows some water broke rings are the result"
So this goes to show, when you get a engine and you don`t know it`s history, tear it down and find out. In my case I did know the history, and wasn`t about to chance it.
 
#5 ·
Yeah, I hope when its all done that a can at least hang with his car. I have no problems taking everything apart and checking it out. I just want to reuse as many parts as possible to save $. The max I want to spend on this engine is $1500. I read an article in engine masters magazine where they used the stock pistons with EQ heads made over 400 hp. I am trying to replicate that build, but they used a newer roller cam block.

I am looking for input from people with more engine building experience, to see if the combination I am thinking of will work.
 
#7 ·
I'm no expert, but I would imagine how to build the motor also depends a lot on what all you'll be using it for. If the only purpose of this engine is to dust your buddy(which is as good of a reason as any, in my opinion) then a nice lopey cam might do the trick. As for your thought about the carb being to small: it'll be close... A 600cfm on a 350 normally is perfect. But if its got a nice high lift cam; a Holley 750 might work out nice. I'd look on craigslist. There's always people trying to hauck used hotrodding stuff for pretty cheap. Or...go the "interesting" route. Hook up a shot of sauce!! The engine might not survive too long. But neither will your buddies ego.

Hammer
 
#12 ·
Smackmatic said:
They just went from free, to "what do you wana give me for em". There in a block a guy I know has, he said there is a pretty good sized cam in it to. He isnt sure how big though.
What do I want to give? Nothing, D-A!

Seriously, used pistons are a crap shoot at best. If he allows you access to them for inspection- pre-sale- then fine. Nothing ventured, nothing gained.

But I'd never front the money for them before inspection. And you're still talking about used pistons.

Price gotsta be low.
 
#14 ·
TNshadetree said:
Your title ask why you shouldn't build this engine. My first thought was, because you can pick up a later roller block with the superior one piece rear seal for a couple hundred bucks. That's why.
This has been bothering me since I got it. Does the hp gain I would get from another block, offset the cost of replacing the one I already have?


I am going to take a look at the pistons next week. Im sure he will let em go cheap.
 
#15 ·
This is really pretty easy, got 1500 to spend, get an engine stand and get started. but I would not spend 1500 on a bad platform. disassemble, magna-flux, align bore if needed and hone cylinders or bore if needed. dress crankshaft as required., assemble on engine stand. cover with sheet, order parts and build the motor your talking about. I built a vortec with roller cam, and performer rpm combination with 750 edelbrock carb. I think my carb is to big and rather have a 600, so use caution there. runs like a ruptured ape, i love it!
 
#16 ·
copper gasket

All
I have a thin *** copper head gasket, I cant remember why i used it, could it have been that I could get a little more compression out of it with out milling the heads. Or was it for heat transfer between the heads and block. Could this head gasket help this guy any?
 
#18 ·
I dont think the .40 over used pistons are gonna work out. The engine that they are in was built in the early 90s, and the block has been sitting in a barn for several years without the heads on it.

Does anyone think the combination I originally proposed will make 400+ hp?
 
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