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Discussion Starter · #1 ·
Hey I am new this forum. I am also trying to deepen my knowledge of vehicles. So I have a 350 out of a 1972 Chevy K/20. I was talkin to a guy about how you can bore it over .030 and make it a 355. How would that make it a 355?? I thought if ya bored it out that much it would make it a 380? Any help so I can u understand this would be helpful.

Also if I did bore this motor out .030 would I be able to get a roller cam kit for use with that old of a block? Or would I have to have a newer block to have that kit?
 

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A simple bore of .030 will net you 5 additional cubic inches. What I think you might be referring to is when a 350 is bored AND stroked it ends up being a 383.

And yes, numerous companies out there still make plenty of stuff for the older blocks. The GM small block was and has remained one of the most popular engines produced so I doubt there will a shortage of parts anytime soon.
 

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You can get a retrofit roller cam for the older blocks...BUT i would be WAY cheaper to find an '87-up 350 block and put a roller cam in it.
350's are not going to disappear overnight...there are literally MILLIONS of them. Good luck with your build. And if you do decide to build an earlier block, there are some things to look for. Under the timing chain cover are cast in #'s...look for "010" and "020" together. That would be a high nickel block. Also the cam bore, look to make sure it's machined pad is perfectly round or VERY close to..if one side is thicker than the other,pass on the block(unless it's the only one for hundreds of miles around!) That means during the pouring process the core shifted. The cylinder walls will be thinner on one side as well.
What type of heads are you planning? Induction?
Reason for all the questions is by the time you spend the $ to build an outdated engine, you could have a 5.3/6.0,wiring and computer up and running, have a better engine and be money ahead.
Good luck
 

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the gen 1 chevy 350 has a bore of 4.00" and a stroke of 3.48". when it's bored out to 4.030" then the volume works out to be around 355 cubic inch.
The 383 has increased stroke, at either 3.75" or 3.80".

best thing to do is google history of chevy small block and read read read. places like gmhightechperformance, hotrod, all those websites who have magazines are good sources of information.

the big thing with the pre-1990 ish blocks which are the generation 1, are their cylinder heads resulted in low compression at 8:1 and sometimes lower. the vortec heads on the later generation 350... the vortec 350... is the way to go and those engines put out 300 hp/tq reliably... and the vortec's had a roller cam, no mechanical fuel pump, one piece rear main seal among other things. they do sell conversion kits to put a roller cam shaft into a gen 1 block, in the end it comes down to cost and how much you want to invest in your gen 1 block vs finding a vortec block, and vortec heads and different vortec style intake manifold. but if you have a budget of a couple thousand to redo the motor and want to do it right, then look into aluminum cylinder heads and intake manifold setup... a roller cam is not the end all be all you can still do up your gen 1 block just as well using a flat tappet camshaft. the biggest influence is cylinder head and camshaft choice regardless of engine size, and choosing those things based on whatever the motor is going in to and how it will be operated (auto or manual transmission and rear axle ratio).
but don't overlook what was previously stated, you may be able to find a LS motor these days for the same price and have fuel injection.... unless you prefer a carburetor.
 

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Discussion Starter · #5 ·
Well this motor is goin to be in a '72 3/4 ton so I am not goin to set it up like a hot rod set it up more for the torque side. I was thinkin keep the hydraulic cam/lifters, edelbrock performer rpm air gap intake, comp cam 204°@.050 intake, bore the block .030 over, quick fuel tech 600cfm carb and edelbrock performer aluminum heads with 70cc combustion chamber.
Does that sound alright? Would anyone do anything differently? Cause I wanted to stay in a 3K budget
 

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Yes it would be powerfull enough, but they like more gear then a 350.

I would only do a 5.3 or 4.8 if I geared it up a bit, and used the OD trans.
 

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Keep in mind the 5.3 makes more power than a 350 did. Plus it is reliable and better power band
 

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I agree with 5.3/6.0. You would have less money in it and would make more power
 

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Discussion Starter · #10 ·
Sweet! Thanks for the input. I figured it would be I will have 4.10 gears in it plus a 4L60 which a guy will give for a hundred bucks which I can then rebuild. Just wanted some more input thanks for the help
 

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HABS SUCK!!
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A martin @ tick cammed 5.3 would piss all over most "built" gen 1 pos 350's.
 

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HABS SUCK!!
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Most are 275 hp smoke blowing wheeze buckets that can't get out of their own way. I've owned and blown up two, 350 and a 385. Invest in an LS instead.
 

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Discussion Starter · #14 ·
Ok cool I am goin to do LS due to I can do it for basically cheaper cause I am goin to go carb for now until I get money for all the wiring etc. And a guy I kniw is goin to sell me a 4l60 for $100. So it will be cheaper to do an ls an then fuel inject it later
 

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Your 3k budget is bare minimum on a 4.8/5.3/6.0. Everything adds up, motor mounts, carb, intake, valve springs, cam, rod bolts, flexplate etc...... I have close to your budget in my heads, sky is the limit.
 

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Discussion Starter · #16 ·
Oh wow haha that is crazy I wish I had that much right now to put into heads that would be awesome! A little at a time I guess I also gotta finish a '55 truck build first then move onto this '72. But once everything gets I will be very happy
 
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