Thread: 283 question

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Hi I just bought a 57 chevy truck and wanting to put a small block in it. Guy at work has a 283 laying around thats need rebuilt so he says. Motor is complete execpt for intake and carb.He wants $50.00 for it.I have a 350 in my suburban but in process of selling it, if I do not I will use it. I am planning on the truck as a daily driver and will do some mild upgrades to motor. Do you think these 283 motors make good builds both in performance and cost to build them? Like to hear some feed back Thanks.

Hey Scooter !!!!! You're being paged. Get yer hands off Mrs. Smith's fair haired daughter and help the guy out!!!

Seriously, in it's day, the 283 was a very good motor (for a chebbie). Scooter will be along here shortly, he luvs em to death and has a ton of good combinations that make em scream.

BABEEP BABEEP BABEEP <pager goes off> a mild street motor? hmmm ok heres a combo........ take it punch it 30 to 287 trust me it will most definatley need it it might need more but .30 is a good start it makes 287 drop in some 6 inch rods for extra torque some 10-10:5-1 pistons what heads??do u want or have? cam id say a 240 or 260-h i need to know what your head #'s are tho for an intake and carb set up i reccomend an edelbrock performer and a 600 holley......... and does your boss got anymore 283's im always buying.......

Do not know if he has anymore but regards to your questions on the heads thinks it is the small ones. What I mean aboout mild is talking about boring it over 30-40 mild cam and itake and 1406 edelbrock carb. Do not want any mean machine cost is a factor at this point oh yeah some good mufflers too.

Auto or standard ? Headers?

you do or dont want to have machine work done?

Posted by Dave:
"Hey Scooter !!!!! You're being paged. Get yer hands off Mrs. Smith's fair haired daughter and help the guy out!!!"

Posted by Scooter:
"BABEEP BABEEP BABEEP <pager goes off> a mild street motor? hmmm ok heres a combo........ "

Just too funny, you GO Scooter

hey i just now realized ive been here for one year <last month> dang i feel old now

Good having you here, Scooter. A year allready huh?? Time flies when you're have fun!! To say the least, you certainly make things "interesting" from time to time !!!!

Scooter.....

Not to bust a nut here....but, for torque wouldn't you want to go with a smaller rod (5.65)? every test I have done a longer rod in a small motor looses a few low-end torque and gains it every where else....oposite is true otherway around....?

In theory a longer rod dwells at TDC a little longer so it should absorb more power to relate to the crank....But also slows down piston speed around TDC....notice how I said the same thing twice but differently

I would build the 283 too....I build and have a truck load full of them.....I think you can do a decent build and knock down more mpg than you would with the 350...I have gotten the best of 26-28mpg in my 57 with 3.73's And I have a 230 duration cam(@.050) w/495 lift flat top's and 64cc double humpers / thin gaskets/ dual plain with a tweeked/reworked spacer....

Note: Crower make a full line of small journal rods...little heavy for my liking....but you can send em' out for a good ol' lightening..

I plan to rebuild a 283 down the line also.
Its a WA suffix which I think is a 1965 model.

But I'm trying to get the theoretical physics clear in my head first.

Torque - so the longer rod (with a standard 283 crank?) raises
the compression ratio increasing torque? Seems like 'dwelling
longer at TDC' would be a function of RPM.

Or does say a 327 crank in a 283 increase torque due to the extra leverage a the crankshaft?

Also - I've read that a 283 moves less than, or right at 500 CFM.
Does a cam allow it to handle 600+ CFM. Probably needs larger valves too?

Any decent reference sites/books on basic gas motor physics?

Thanks - Bert

SBC....

Changing rod length does nothing for compression.....how ever it does manipulate piston speeds around TDC...

A shorter rod has a faster piston speed around TDC and needs a larger head to take care off breathing at a higher rpm...

While as installing a longer rod slows down the piston speed around TDC thus absorbing more of the combustion power.... A longer rod also relates to less piston and cylinder wear over time.... for stock or mild street I would leave the stock size rods in it....but thats me....you could gain more by going lighter rotating assemble in a light vehical....

there are a lot of variables to consider when building an engine...

cfm is figured like cu.in X rpm / 3456

ex. 283 x 6500 / 3456 = 532cfm bump it up
ex. 283 x 8500 / 3456 = 696cfm

Thanks Doc -

I thought if I could put together a typical 220 HP 283 I'd be happy for starters. But I think I need 600+ CFM (4 barrel) to do that.

I would think a shorter stroke will increase RPM.
Or a higher cumbustable mixture to get it moving faster?

I can't find a proven specification for the 220HP 283 other than 4 barrel carb in general descriptions.

Then there was a dual-4bbl 275 HP Corvette engine I think.

OK - not ready for that!!!!!

Why a 283? - that's all I have.
I have considered the 327 crank but I don't think the 1965 block will accept it.

Bert

A longer rod will "park" a little longer at TDC, but it will go through BDC quicker. There's give and take with everything. Some builders will use a shorter rod to dwell longer at the bottom to help cylinder filling.