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

I am building a 283 for my 56' 210, and want to try and make 300-325HP. It's a street car. I have a .030 block, with Jahns domed pistons(small dome) a pair of 1964 461 fuelie heads with 1.94/1.50 valves, and 64cc chambers. For a cam I'm going to use Comps L79+ 276/283 duration and .468/.462 lift. On top I plan on running an Offenhauser 2x4 intake with 2 Holley 450cfm carbs.

Do you think this will make 300-325HP?

 

Sounds like a good combination. Maybe be a little overcarbed though.

 

A single 650 carb would probably work better for you and remember these engines make their power by high revs. You will need a 4.11 rear gear and four speed for it to drive right.

 

Comp Cams has a software simulation program called CamQuest. You can download from there site. You plug in the variables of the engine and the cam you're going to use and it spits out a prospective HP and TQ curve. Of course it's not going to be exact but it lets you know if your in the ballpark. I did a quick one with your info and it said 365HP at 6500 and 349tq. at 4500. I'd say that's high but you're in the ballpark.

 

sounds like a screamer!

 

This sounds awesome!!! I'm going to build another 283 (if I can't find a 365/327) for my '54 Chevy when the time comes. I'd like a similar HP output for the project. Man I love these little screamers!!!

 

It will be a sweet engine - but really not enough info to take a SWAG at HP. I cut my teeth running +.060 (292) and +.120 (301) 283s in the late 60's early 70's. Forged 10.5 - 11:1 pistons, and a tank full of 260. Unfortunately, that combo just would not make it on modern pump gas. Build it right and don't get too carried away with what the HP might be. Overall speed is a combination of things - HP being only one.

 

looking at the graph shows a peaky engine. not a flat torque curve. Won't be much until it comes on cam at 4000 then,,,,,,hold on.

 

How realistic are those numbers? It's interesting how little effect the carb size has in the simulation, compared to headers vs manifolds, etc.

 

GM squeezed 315 out of them in '60 and '61. That was 11.5:1 special duntov solid cam and Rochester fuel injection.

Your setup is probably about as close as you are going to get short of building an exact copy of the '60-61 Corvette Special Road Race package.

 

4.11's and a posi for sure!!! I have an M-20 in the car now, and an M-21 ready to go. New 17lb steel flywheel, RAM 10.5" clutch, and an Ansen scatter shield!!! I also have a new 70's Wiend hi rise open plenum 4bbl intake. Or should I use a 60's Corvette 350HP intake?

I like the look and sound of the 2x4's but, I know it's gonna be a bit to much, and a pain in the a** on the street. A Holley 4150 750cfm with mechanical secondaries would be better...

 

Two factors that I'm concerned with. Number 1: how good are the cylinders? They have to be perfect to make good numbers. Number 2: How good are the heads? Are the valves sunk? Have they been cc'd? the early heads have a broad differential in flow numbers. It would be good to have them flowed and see if they're good or mediocre. I agree that a 2X4 intake isn't the best.

 

750 is still too much carb.

 

The width of the combustion chambers on the 461 heads causes the chamber to overhang the small 3.905 inch bores. That is not a preferred situation. I ran into that on my 283 build and ended up changing the heads to the smaller chamber 520 castings.

 

750 will work fine i have had same combo in a chevy II MADE 306 HP ON DYNO

 

Number 1: How good are the cylinders?

What do you mean? How well were they machined? Well, I bought the short block from a machine shop. The owner was retiring and this was all done. Ready to assemble has new cam bearings, and freeze out plugs and came , with the crank, rods, and Jahns pistons for $450.00 I did not check the wall thicknesses because it's only .030

Number 2: How good are the heads?

They are in real good shape. Valves are not sunk, and the have never been decked. As far as cc'ing them goes it's not a bad idea. Flow benching them wouldn't hurt either but, is it all worth it for a street motor?

 

My stroked 283 (317ci) made 403hp with 291 heads (1.94/1.50 valves), a COMP hydraulic roller (.566 lift, 242/248 duration, 112 degree lobe sep. angle), 10.3:1CR, roller rockers, and a lot of oil control (scraping-style windage tray, stove-pipes in the lifter galley cam holes, and good rings). I self-ported the heads and flowed them. The torque curve was pretty good, climbing steadily to 399lb/ft @ 4400rpm, while hp climbed to 403 @ 6,000, and started to drop off.
Tunnel ram with a pair of 660cfm center squirters, with the choke towers milled off. Pump gas.

This same engine made 365hp @ 5,800rpm and 370lb/ft @ 4,800 with an Edelbrock C26 2x4 intake and 500cfm carbs; and 377hp @ 5900rpm and 386lb/ft @ 4,700 with an Edelbrock Air Gap 2x4 and a pair of 500cfm carbs

It made less with several single 4bbl intakes, all dual-plane, including a Performer RPM.

An Edelbrock tri-power with Speedway Stromberg-style carbs made 372lb/ft @ 4600rpm and 368hp @ 5600.

I have no idea what a single plane intake will do on this combination, but this should address the issue of "too much carb."
Let it breath. With a vacuum secondary, it's not going to take more than it needs.

-Brad

 

Its all worth it if HP is your goal. A street motor and a race motor should be built the same way precision is key to squeezing HP out of anything. You are expecting a lot from your little motor, give it what you expect from it. What you want isn't impossible the GM engineers proved that beyond a shadow of a doubt, but to get something you have to give something, what doesn't cost has no value.

 

A 61 283 270 HP Vet motor had two 400 cfm carbs with vacuum secondaries, for what its worth.

 

What does the compression ratio work out to be? You might have a hard time running that combination on pump gas, especially with iron heads. 64cc combustion chambers and domed slugs will probably put you up over 10:1 and that is kinda pushing it with 91 octane.

 

I love 283's. They are high revving which makes a 4 speed the way to go. I've a 283 in my 34, with Edelbrock Torquer, Holley 650, 461's, Ansen, Muncie and it pulls like a freight train.

Put extra work/$$$ into your heads (cc, matching intake ports to the heads, etc). All those little extra's to the heads will get you your extra power.
I think your setup will knock out an easy 300 horsepower, but you may need to add octane booster. You can always "cheat" and toss on a NOS plate later if you still have an occasion to really wing it.
Good set of headers possibly adding a crossover pipe.
With your 411's, maybe consider a cam that kicks in at 3000rpm instead of 4000 to make it a bit more streetable, otherwise you may find yourself grabbing another gear just as the engine is getting into its "party mood"!!!

 

??????? They were Carter WCFBs with mechanical secondaries.

 

running the 64cc style heads on the 283 drops the compression,

you will make up for it with the dome pistons, but you neeed to check the block to see if it has been decked at all and figure out how far in the hole the piston is sitting.

the spark plug location on 461's tends to interfere with some dome pistons . Jahns are heavy enough that you can relieve that area if you need to , but they need to be checked in assembly.

it wont be the most stoplight friendly thing with the tunnel ram, but it and the small stroke will like the upper rpm.

Fred

 

SamIyam knows how to build a thumper 283

 

Hmmmm, now that's an interesting thought!!! I do have a small journal 327 crank...that would make a 302!!! Even sweeter!

Comp also makes a tight valve lash 30/30 cam in both solid and hyd grinds. The solid is a little more aggressive, then the hyd. But, is a solid cam the best idea for the street. I use an oil with zinc in it, and mix av gas in with 93 octane.

 

NOPE not a 302, but a 307 plus your .060 so about 316". I don't like that combination, 307's were never the torque motors they were supposed to be. Keep it under 10-1 (9.5-1 is better with the gas) and the 1.94 heads need to be carefully checked for interference. The big problem with putting "fuelie" heads on a 283 was the large 2.02 valve. Your 1.94s should get by. I don't like EITHER single quad manifold you speak of. Get with Edelbrock for the right one for your mini motor. THe factory hirise was built for more inches and less RPM as was the Wieand. A Holley street dominator might do the trick...port match the heads...
Good luck!!

 

lol... yeah a tad......

 

I think with your combination you will have a tough time making over 300 hp.

 

The Comp 30/30+ solid cam is a modern grind. Duration 284/291, 247/[email protected], lift .504/.498, and the valve lash is .012.

 

I have a 283 bored .60 over with 305 heads, Melling cam (L79 similiar) edelbrock intake, edelbrock 550 carb and HEI ignition. Running 2 1/2" Ram Horns and Smithy mufflers.
From what I can gather from checking several sorces, it appears to be in the ~285 hp range. Runs fine on premium pump gas.
I am running a 4 speed with it. It is very responsive, and runs awesome (but no big block.)
I love it, but have only had it running for two weeks now....
A fellow nearby has a dino, and I am wanting to check it, but short on funds...
Good luck...