Want to get 300-325HP out of a 283!!!!!

Was this a street motor? I am using a hydraulic roller in my 327 build. It's quite a bit tamer though. It has a lift of around .480 if I remember right. It will be running a 3x2 setup as well.

 

Keep the M-20. That low RPM power's (or lack of) gonna need the lower 1st gear

 

Also, I'd run a set of Power Pack (4 bbl) heads with some pocket work instead of the bigger valve/small bore combo. Flow's not gonna be all that good with the cylinder shrouding the bigger intake valve. Also, you might pick up some wanted low RPM torque with the PP heads

 

---------------------
["750 is still too much carb."] - Not
if its got vacuum secondaries and it's
calibrated for the engine with the proper
jets and power valve and the proper-sized
spring in the secondary diaphragm chamber.
Remember too, that in '67, '68 and '69, the
factory put 780 cfm Holleys on production
302 Z/28s - and the 302 was basically a high
compression .125-over 283 with a 327/375
hp cam. Just for the record too, in the early
'70's I built a 283 for my '64 Chevelle with
a combination similar to what NJ196 is planning.
Mine was a .040-over 283, also with Jahns
pop-up pistons and 1.94/1.50 461 heads -
but with a 314-degree/.440lift Crane Fireball
solid-lifter cam and a 735 cfm Holley carb
from a '69 Ford 428 CJ, on an Edelbrock
3CBX intake. The cam was a bit much on the
street in the little 283 - it would rev like there
was no tomorrow and was still making power
and pulling hard, past 7000 rpm, but was
severely lacking in low-end torque! But the
735 cfm carb, once we got it dialed in with
the correct jets, power-valve and secondary
diaphragm spring, worked perfectly. I don't
know what my engine was making for hp,
but going by the e.t and mph in the quarter
(with open headers, it usually ran 14.2 to
14-flat at about 101 to 102 mph) in a 3400
lb, 4-spd '64 Chevelle with 3.36 gears(!),
I'm pretty sure the hp had to be in the
low-300hp range.

Mart3406
-----------
P.S. To NJ196 - I love 283's too, but if I was
building a hot, street-drivable 283 today, I'd
build a 350, a 383 or even a 406 cubic inch
small-block and disguise it to look like a 283!!
========================

 

Piston deck - to - cylinder deck is critical to making a fatter torque curve in a 3" stroke engine. This aspect has yet to be addressed. This deck height (at TDC) needs to be measured, added to compressed gasket thickness, added to combustion chamber volume (measured, not assumed) to be able to accurately calculate compression ratio. Squish (quench) is just as important as high compression for developing a fat torque curve, and reduces detonation tendencies. Also, the shorter LDA is the way to go with high compression.
Light weight cars (T-Buckets) tolerate high compression - 91 octane much better than 3500# plus cars. Keep in mind the convenience of running readily available pump gas compared with having to mix in race fuel or av-gas every tank full.
Bottom line: a 325HP 283 will not exhibit the mild manners of the 325HP 327.

 

Yes they were/are. I had a pair that came on the 327 in a 57 Panel truck that ended up on my T bucket's 283.

That engine sounds a lot like the engines that friends built for their drag cars here in town in the 60's and my boss in Waco,Tx built for his dirt track cars in the mid 70's.

I ran a 327 with 12.5 Jahns pistons and an Engle solid lifter cam with 2.02 heads in the mid 70's and had a hard time with gas then. I'd hate to have to hunt for gas for that kind of compression now.

 

Can you make that kind of horse power - yes, but the light that burns twice as bright burns half as long. You want 350hp, get a crate motor and tell everybody it is a 283.

 

Not sure what degree of lobe seperation you have? That will also effect compression along with advancing or retarding that cam you have. I would come up on the lift, if you have the pistons fly cut enough, and tighten up that lobe seperation to 110 deg or less. It will still be fine on the street and give you a little more grunt if you put a little steeper gear in it like Falcongeorge said.

 

This is the answer. You can have a peaky, cantancurus, needs tuning all the time, subject to break something 283, OR a solid, dead reliable, starts easily, drives easier 350. Set it and forget it. 325/350hp 350 with WAY more torque than a 283.

I'll take reliable any time.

 

Bingo! I'll say it again. The 461 heads are not the best choice for a 283. The combustion chambers on the 461 heads overhang the bores (not good), you will have to pay close attention to the piston dome to spark plug clearance and the small bore shrouds the 1.94 valve. Some mildly worked PP heads are better for the 283.

 

Ya, cause we're all about new crate engines here on the HAMB. The home of traditional hot rods. Just throw that 283 away cause they only lasted for 150,000 thousand miles in the original cars they came in. You know, unreliable.

 

I don't think I mentioned "crate" engines. I'm betting that 99% of the people on this site can't look at the engine in my '33 and tell me what it is. But that's not the point. If I had a 283, I'd build it as a 283 PowerPak and know its going to start, run and get me home. Like they did in the original cars you mentioned......

 

Wouldn't that be like rolling up a sock, and putting it down your pants?

 

Well it's your bumpstick...

 

---------------
Nope. A 327 crank in a 283 block gives
you 307 cubic inches. The factory offered
this combo from '68 to about '72 - albeit
in large journal form - as a low-performance
entry-level V8 to replace the 283. A 302
(also called a 301 'back in the day') - is, take
your pick, either a stock, 3-inch-stroke,
.125-over 283, or a stock, 4-inch-bore 327
block with a 283 crank. The '67 302 Z/28
used the small journal 283 crank while the
'68 and '69 302's used a dedicated,
large-journal version of the 3-inch-stroke
283 crank.

By the way, despite popular belief, there's
nothing wrong with a 307. Pre-1968, it was
a common, low-buck stroker combination
for guys running 283 blocks. The reason
they are looked down upon is that when
the factory built them, they where only
offered in cars in low-compression,
non-high-performance, 2bbl form while
the factory concentrated on the 302 Z/28
and the bigger 327 and 350 engines. for
their performance engines. OMC and
Mercruiser used the 307 -with a better
cam and heads and a 4-bbl carb - as
a medium-performance marine engine,
with factory marine ratings up to 250 hp.

Mart3406
===========

 

Just downloaded CamQuest. I'm going to play with it a while first ...

 

Funny !!

 

Mine is a large-journal '68 283 (.060-over) with a 327 crank. (i detailed it earlier in this thread--403hp at 6,000 rpm on pump gas)
-Brad

 

Makes me wanna build a 283 for my 27 chev

 

Made 290hp with .030" over 283 with power pack heads with some work. 30-30 Duntov, dual point dist, 10.5 Forged True Pistons and a 1960 Rochester FI unit. Car liked a 2.52 low gear 4-speed and 3.70 rear. All this in 1964 in a 62 Chevy II. A single 4 barrel would have made more but it got 22 mpg with 3.08's. Good Luck.

 

Do your Home work , Lot of math involved, then have your custom cam ground ,
A good programs do work ,
Your Hp can be achieved, with a few part change ,
If you want to stick with the parts you have ,
TIP THE CAN !!!!
Add """"Nitro """
You will Succeed 325 no problem.

 

in 1956 a 265 chevy came from the factory with two 380 cfm 4 bbl carbs. that's 760 cfm on a 265. So how is 750 cfm to big on a warmed up 283? My opinion the chevy engines breathe so much better than most other makes you can successfully run a larger carb. and with vacuum secondaires your engine will not pull more volume than it can handle.