How would this little motor run if I had it bored 60 over(292?)new speed-pro pistons with a small dome(.4 I believe), 1.94 heads
(here is what I'm not to sure about)with 76cc
chambers, solid lift comp cam @ 294intake 294exhaust .525lift on both valves, victor Jr
and Edelbrock carb @ 600cfm, not to sure about the headers yet. I know I can build a sbc 350 but I like 283's and like a challenge, compression is my main concern
any advise would greatly be appreciated..

That motor won't have enough compression, particularly for that big cam/intake. You need a smaller CC head.

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79' Z28 4-spd- built 355, TRW 10:1 forged flat tops, WP SportsmanII heads, Crane Energizer 230/230 duration .480"/.480" lift, Edelbrock Victor Jr., Holley 750cfm, Dynomax headers, dual 3" flowmasters :) 3.73 Posi 10-bolt

Try to find a pair of -461 medium valve heads for the little engine to get the CR. around at least 9.5 to 1 for pump gas! W/P's 58cc, SR305 Torquer II's or whatever they are called would be fine with medium valves.

Also standard 1/8" half dome pistons should be fine (if you don't go over a street gas CR. ratio with bigger combustion chamber heads),if you can still find them and believe it or not, the little engines don't produce enough power to really tax a set of good cast or HE type pistons. But, yes go with forged if you want!

Imho, a 270 duration solid cam would be more then enough b/c you are not really filling that big a cylinder. A modern version of the little -097 Duntov solid cam is ideal!

(287/287, 228/230, about-110/106, and max lift).

Add an 1850, 600cfm vacuum secondary Holley, jetted and secondary springed right, plus a set of 1.5" four tube headers and I will garantee a great big grin factor if you gear the little bugger right. I remember when they ruled the streets years and years ago.

And I have a big soft spot in my heart for the little engines! pdq67

I agree with the smaller chamber heads. It is harder to build compression with the smaller displacement motor. The bored out 283 is close to a DZ 302 in bore and stroke so I assume you want to spin it. I was doing some desktop dyno work on cams for a 302 and found this little number that looked too good to be true compared to the GM factory "30-30" cam I have installed. It is a PAW grind 10341 with 246 duration @.050, 264 advertised with .471 lift and 108 degree lobe centers. It runs solid lifters and .030/.030 hot lash setting. I have been meaning to call them to ask about the cam and verify the numbers. It looked great on the screen. I know the GM cam is not the best piece from a performance standpoint as the duration is way too much but it is correct for a DZ 302 so I'm running it. Otherwise, I might go with that PAW piece. I am sure it is a copy of someone elses grind.

-Mark.

I really appreciate all your inputs. I still have the stock heads which I believe are 58cc but smaller valves and the compression may be above pump gas ratio, what I was really looking for was a set of 1.94's with 64cc chambers but not real sure what these would do for compression, someone offered the 76cc's heads to me but figured the CR would not be high enough to use, does a huffer come to mind?

A LUNG on the little engine!!! Super.

I bet a Holley/B&M 144 street blower would be great, or if you really want to rock, the 177 size!

8 to 1 CR., a mild cam with 114 centers to control overlap and pump her up!

Go for it and tell us what happens. pdq67

Just don't go overboard with the boost.

Remember, the more you compress air, the hotter it gets, detonation moves in.

But a 283 with a huffer, can you say, seat of the pants meter pegged?

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Everett 68/350/PG/11.90/115mph

I can hear those Mustang weenies now - "yah you beat me but you've got a bigger engine!"

Then comes ET47's reply - "what do you mean? it's only a 283."

Just keep the cam small - like 220* duration at .050 max. The 270s PDQ suggests would be ideal IMO. Same with the carb - no need for anything over 600cfm. Headers too, a 1-5/8" tube header would be more than enough. A set of good breathing heads, a Performer RPM manifold and bingo - 300+ high winding HP.

ps. and if you really want to spin that little puppy, add a single plane manifold and the bigger Comp 282s - Desktop Dyno says 381 HP at 6500 RPM.

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68 Camaro, 383 small block with TH350 trans. 11.98's at 111mph and never trailered.

[This message has been edited by Eric68 (edited 03-22-2002).]

With a "small" engine like the 283, cam selection and compression ratio are critical to how it will run. Low compression will kill the horsepower number, but if you install a supercharger it will scream! My 302 ran great, but that was due to the 30-30 cam along with 11:1 compression ratio.

Eric68, are you talking 381Hp at 6500RPM with or without the blower?

Way back when, a "balls-out" 292 could be made to produce upwards to something like 1.75hp/inch or so!!! But it was totally unstreetable! They reigned supreme in their weight/cubic inch class in the old tri-fives and such! pdq67

Thats without the blower and running 10:1 compression. Stock SR torquer heads.

With the blower we could drop the compression to 8.5:1 and just break the 400 HP mark with a small supercharger http://www.camaros.net/forum/biggrin.gif That might not sound like much more, but you'd make some serious torque with a small roots type supercharger.

[This message has been edited by Eric68 (edited 03-22-2002).]

ERIC

Can you do a dyno with the setup that I have and let me know where I would be with HP and TQ. Anything close to what you got that 283 will be a blessing in the sky for me. Cant wait to see the results.
I dont think I will go to sleep tonight, Santa Clause might be comming early in 2002, "283 400hp" unbelievable!!!!.

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DTL504

84 Z28 Camaro, 2 Seater Convertible, w/283 bored 80 over,flat top pistons, 202/160 Camel Hump Heads 64cc (3782461), Blueracer Camshaft: Duration 230/230 @.050 Lift 480/480 109 degrees, Edelbrock RPM Maniford, Holley 670 Avenger Carb, Hooker Ceramic Coated 1 5/8 Headers, 700R4 Transmission w/Transgo Reprogrammed Kit, Transgo Shift Kit and .500 Vette Servo, 3:73 Limited Slip., Kyb Shock, Spon LCA and ADJ. Panhard Rod.

Hey ET47,

I just built one:

*283 +.060= 292 Cubes
*flat tops (4 reliefs from speed-pro)
*Original 1964 Powerpack 58cc heads, and I had 1.94/1.50 valves put in
*comp cams 268XE with .480 lift intake
*Edelbrock performer
*Edelbrock performer 600 vac secondary
*My combo yeilds right around 10:1 with the flat tops.
*3.91 gears

I think I am way over cammed, but it really rips when I wind it past 4000RPM. I killed the low end with my 2004r automatic. This combo really needs a manual. Victor JR I think would be a better choice. I run premium pump gas and no problems with detonation. You could yeild a similar compression ratio with a dome and bigger combustion chamber. I have a feeling that flat tops are better for flame propogation. On desktop dyno, my combo yeilds right around 320HP.......... And man does it sound GOOD! With that cam and 2.5 flowmasters, it really hits hard, and the cam is REAL choppy.

Matt



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1969 Z28
1966 Corvette 427
1960 Austin Healey (283/2004r)
1932 Ford 425 buick

Man, you guys are making me miss my Vega with all this talk about 283s...
My combo was real simple at the time (early 80's)- 283 with stock bore and bottom end, 30-30 cam, 58cc Powerpack heads, steel Quadrajet manifold, Holley replacement 650 cfm Quad, re-curved GM distributor with a Supercoil, and Hooker V-8 Vega headers.
Trans was a TH-400 with a Vega converter, which gave it around a 2500 to 2800 stall speed. The rear was the stock Vega with 3.73 gears out of a Monza and welded spider gears.
The car was a 74 Vega wagon, probably right around 3000 lbs. or so, and with 13" Kelly Supercharger 60's it was a blast to drive.

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68 Camaro 355", TH-400, 3.73 10 bolt, Rally rims.
69 Nova 355" TH-350, 4.88 12 bolt, 150 shot...click here to see it. (http://members.tripod.com/pete_2112/petesnovapage.html)
And a garage full of vintage bmx bikes.

i think you'll have a blast with one of those suckers and a 4 or 5 speed tran's so you dont need to worry about the loose converter needed for it.

<BLOCKQUOTE>quote:</font><HR>Originally posted by DTL504:
ERIC

Can you do a dyno with the setup that I have and let me know where I would be with HP and TQ. Anything close to what you got that 283 will be a blessing in the sky for me. Cant wait to see the results.
I dont think I will go to sleep tonight, Santa Clause might be comming early in 2002, "283 400hp" unbelievable!!!!.

<HR></BLOCKQUOTE>

I have no idea what your combo is . . . but I could play around a little if you let me know what you're starting with.

Another note - unless you really want to spin a 283, I doubt a Vic Jr would be a good choice. I think that the plenum volume is on the big side for a small engine and a good dual plane like the Perf RPM or Air Gap would pull plenty hard through 6500 or so (on the little engines). Save the Vic for a serious rev monster 283 - the Comp 282s and Vic Jr would probably start pulling at 4000 rpm and would really need gears and a stall to take advantage of the high rpm power.

Heck, a stock cast-iron 300hp/327 AFB manifold will flow OK for the little bugger. Imho. pdq67

(I have no idea what your combo is . . . but I could play around a little if you let me know what you're starting with.)

Eric68
here is the combo that I would like to have dyno.
Check signature below:

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DTL504

84 Z28 Camaro, 2 Seater Convertible, w/283 bored 80 over,flat top pistons, 202/160 Camel Hump Heads 64cc (3782461), Blueracer Camshaft: Duration 230/230 @.050 Lift 480/480 109 degrees, Edelbrock RPM Maniford, Holley 670 Avenger Carb, Hooker Ceramic Coated 1 5/8 Headers, 700R4 Transmission w/Transgo Reprogrammed Kit, Transgo Shift Kit and .500 Vette Servo, 3:73 Limited Slip., Kyb Shock, Spon LCA and ADJ. Panhard Rod.

DTL504,

307 HP at 5500 RPM, 315 TQ at 4500 RPM. If you have flat top pistons your compression ratio is only 8.1:1 with the 64 cc #461 heads. You need a dome piston or smaller cc heads IMO. You could always put a blower on it it or run some Nos to take advantage of the lower compression though. If you can bump the CR to 9.5:1 here are some other cam choices:

Compression change alone with current cam: 331 HP @ 6000, 335 ft/lbs @ 4500

Comp Cams XE268: 323HP @ 5500, 339 TQ @ 4500

Comp 270s mechanical: 320 HP @ 5500, 357 TQ @ 4000

The Comp 270s would work nice with about 9.5:1 compression and would have great TQ for your overdrive trans. The XE 268 would also work. You need a 3000 stall for your current setup IMO you could get away with a 2500 stall with the Comp 270s IMO.