Thread: sbc 350

Tweet

[QUOTE=gassersrule_196;472208]why cant you bore a 350 .080 over? seen it been there done that. just like you "cant" bore a 283 .125-.155 over been there done that to. works fine. taken proper precautions.


There is nothing alike from a 350 to a 283.Except the 283 is much,much,older and more likely to crack. If by chance you got one 283 to run without running into water,doesn't cover ALL production 350's. They just don't compare.

Originally Posted by gassersrule_196

those precaustions would be, checking for core shift, magnufluxing it among others.

None of the above really is useful to check for a acceptable candidate block to be bored .080. Core shift??. Now that is rolling the dice.

have you personally built one to these specs, to be able make this assumption?

Been drag racing pretty much my whole life soon to be 65 yrs old and spent yrs working in the Dyno rm at a Chevy engine plant.Not a defense.Just pure facts.

Originally Posted by gassersrule_196

this is why i said, "and other precautions"

It is interesting here that you never said anything at all about the most important precaution needed. Sonic check for wall thickness. Even at that "if" you get it bored out that big,it will leave the bore's wall so weaken,it is just a short matter of time before a issue occurs. Then to shorten that time up,to tell this O/P to install a performance cam is bad advise which given what the forum is about,I couldn't just let it go. Again,just the facts.

In my opinion,you can not,should not,generalize advise based off what is a well know proven high risk factor. I'm just doing my part here with just the facts.

Going with such a bore, would this mean using a small diameter cam & clearaicing ( notch )the bottom of the cylinder like in stroker motors?

Looks to me like the OP gave up with everyone bad-mouthing his .080 block and not answering his cam question that he gave up and left.......


BTW, Scooter has been around here awhile and posts all his draggin' plans and results.... He had a couple smokin' sbc's in that little yellow Nova and for me if he sez he had a + .080" block, that's enough for me to take it as fact.... Like I said he's a real racer and doesn't just post "what if" scenarios and things he read online somewhere.... I think most of us realize that sonic testing a block is a common procedure prior to going to a large overbore, hardly anything worth quibbling about anyway....

I'll stick with real racers and people who actually build engines for my information any day!!!! You Da Man, Scooter, keep twistin' them small blcoks!!!!!! (Even if the "experts" tell you it won't work)

awwww--scooter's going to be driving rigs where the wrist pins weigh more than his crankshaft did in the sbc

But,but,but,I did answer his question three times telling him I suggest for him not to put a performance cam in a .080 block.

There is a hell of a difference between a screaming gasser of yrs ago and a certain expectation of "windowing" a block to throw it away vs a guy who is just purely out on a cruise night finding his engine puke all over the hot dog stand's driveway.

Don't think the experts ever said it couldn't be done,it just not advisable and like with the gassers of old,won't last.

David.In terms of me personally.I did my time in C/MP and D/PM with moon shot SBC's. I built them,drove them,and blew them up. Rockcrusher 4 speeds,welded spiders,and all. So been there done that.

you can bore a 350 80 over caues ive did it and drive it everyday. i got it from a guy and its just sat in the back yard for some years untill this year i went through it and built it the year of the motor is from 77-79 bored 80 over caues its stamped on the pistons with some older 327 heads

First off,I want to say I am glad you cam back. Do think we have talked about both sides of the topic. Debates like is aren't common,so I don't want you to get the wrong impression. I do think I clearly stated my opinion and therefor moving forward I'm out.

Originally Posted by my64

you can bore a 350 80 over caues ive did it and drive it everyday. i got it from a guy and its just sat in the back yard for some years untill this year i went through it and built it the year of the motor is from 77-79 bored 80 over caues its stamped on the pistons with some older 327 heads

My64,
Thanks for hanging with us through all of the off-topic rambling that never addressed your question. You can choose to believe what you want from whoever you want, but you've got the engine, you use it regularly, and it's been doing fine for you so bore size should be a moot point from this point forward. Can you share some details about what it's in (for weight reference), what gears you're running, stick or auto, and maybe tire height as well as what you're wanting from the new cam? With that we've got a few guys who can help guide you in your cam selection.

its in a chevy c10 stepside, its a turbo 350 auto. its got the factory rear end and gears in it and weight im not to shure

and since it is bored 80 over i was just wondering on the cam and if i could go biger becaues if i do that it changes everything and i figuerd alot more people have did an 80 over on a 350

The C10 gives an idea on the weight, as opposed to a 2500# street rod. Are you just wanting more "grunt" for playing, and using it as a daily driver or are you wanting torque for towing? About what rpm do you turn at say 70mph on the highway?

lol yes wont last been going strong since 1999 lol i have no idea what im doing

original poster, your original gear may be 3:73's thats my guess pretty common stock gear, what compression do you have, what intake and carb do you have?

so he raced a 080 350 no a 283 more luck then any thing if not sonic checked .but small engine with no stroke not much wall loading is there . no dave the expert use a sonic checker then they tell you IF it will work . seen any 4.080 bore race pistons ? last time i checked i do machined many REAL race engines this year need a listed of names and numbers . but tell me i did not ? i am getting old .my mine may be playing tricks on me???? . the deal here is just bullshit as not one of you guys would take a good 350 that would clean up and go to 080. and if some one posted on here ... if smart ...would say the next over size to clean it up and save the block for another rebuild . or what would you pay for any engine thats been bored to the hilt on bore size? .am i missing something ?the guy pick up a engine and wanted to know about the cam hitting as the bore was bigger ? and said it was 080 thats alot and he knew that ? but did not know if the new cam would clear or what cam would? that is no .the rods will not hit the cam. use any cam that will fit for piston to valve clearance work for your build.

and just to get things out there you can take a 350 and bore more than 80 over you can go all the way to 120 over. this 80 over build is not my first but i have never put a bigger cam in a motor with that kind of bore

Originally Posted by my64

and just to get things out there you can take a 350 and bore more than 80 over you can go all the way to 120 over. this 80 over build is not my first but i have never put a bigger cam in a motor with that kind of bore

if you know all stock gm 350 can go 120 bullshit .. very few are sound at 060. very few make a race piston that go past 060 . i have a machine shop with a rotter f2b thats bored alot of iron blocks . i sleeved the f#$king things and started to break threw shade past 100.. you can hear the walls go thin just by the sound of the bar cutting . if one makes it lets see what happens when you put a deck plate on it with out a short or full fill with block rock.yes you can bored a dart SHP block out to 4.165 . i bored many bbc from 4.250 to4 4.500 then to 4.625. them are not stock blocks. if you know how far you can bore them you should know any cam will fit if you have the PV