alright guys i need your advise. i have a sb 406 and i am going to start rebuilding it here in a couple weeks. but im not sure what to put in it. i hope to make like 550 ft lbs of torque and about that much horse power. but what components do yall suggest i put in it, like which pistons, heads, cams, cranks, or who i could call that would give me honest info about all of this thank in advance :D

 

Do you plan on running race gas full time? The power numbers that you're looking for are going to be tough to produce on anything less than raceing gas unless you start adding a supercharger or turbocharger.
You are going to want good flowing aluminum heads like the AFR 220 or Brodix. The camshaft should be a full roller, solid roller would be a better power producer. You will have to wait until the engine is finalized before selecting a camshaft so you can figure your dynamic compression ratio, but as a point of comparison, my 406 with a solid lifter (not roller) cam of 300 / 310 duration produces about 450 HP in Desktop Dyno. On your piston selection watch the quench area closely to keep the pocket as closely matched to the cylinder head quench area as possible. On the side of the piston away from the spark plug you will want a .030 piston to head clearance to promote good flame travel. .030 is also the gasket thickness of most head gaskets so you are going to have a decked engine to produce this.
The entire package needs to be looked at closely as the compression ratio will spike up quickly with the wrong parts selection. The pistons will most likely have to be a dished piston, dished on one side only. The cylinder heads should be 70 c.c. or more if you are going to get the compression ratio in the pump gas ballpark. The camshaft will have to have a duration long enough to produce the power that you want but not so much that it bleeds off too much dynamic compression. Thicker piston rings are better for a street engine, while thinner rings will work for a race engine. If you try to use a connecting rod longer than 5.7 inches you are going to have a hard time finding pistons that have thicker rings.
My 406 has 11 to 1 static compression ratio. I think that is too much for a pump gas engine, and would have reduced this to 10 to 1 if I did it over again tomorrow.
Just between you, me and the fencepost, I wish that I had just bought a ready to run engine from one of the known quality vendor like AR Racing.

 

Check out www.airflowresearch.com, they have a few 406 cu in dyno results. Nice torque numbers.

 

:iagree: :iagree: :iagree: They have 2 406's that put out 550 and 570hp ON PUMP GAS. AFR makes the best flowing heads hands down.

 

I can vouch for the power levels. My new 700r4 trans is now toast after only 500 miles.Pump gas is not a problem if you run aluminum heads and 10:1 cr or less. I ran my 406 all last summer on 92 octane with no problems.

Be advised when you reach these levels of power,you WILL need to upgrade lots of other things.

 

RPM Torque H.P.
2500
3000
3500
4000
4500
5000
5500
6000 463
468
457
465
534
540
510
483 220
267
304
354
457
514
534
551


Dyno Test Criteria
Horsepower:
Engine:
Heads:
Compression:
Carburetor:
Ignition:
Cam:

Exhaust:
Fuel: 550 HP 406 Street Engine
406ci
AFR CNC Cyl. Heads 210cc Race Ready
10.3
750 Carb
MSD HEI Billet Distributor 36° Timing
Lunati Hyd. Roller Cams 232°/242°
0560-.570 lift W/ 1.6 Rockers
1 3/4" Headers
93 Octane Pump Gas


what do yall think of this engine
do you think it will be very street friendly. right know i have about 400 hp so im pretty sure everything can handle it, except my engine mounts (hopefully)
and i will either be getting a 373 or 411 rear gears with a 200 4r trans so it should run really good
:auto: :chevy

 

With that cam it sounds like you are going to be wanting at least a 2500 rpm stall converter, 3000 rpm stall would be better I'll bet. Keep us informed on how the 200R4 does with this engine. I think that they can be built to handle that much torque but I'm not able to do it myself so I'd be intersted in hearing who can build one right.

Overall that sounds like a great combination.

 

Those numbers on pump gas should be very possible with the parts available today. Don't skimp on head choice. You can get away with running a tad more compression with aluminum over iron heads ;) . I agree with the solid roller cam.

You may want to consider a partial block fill if going with a stock production block as this will help strengthen the block along with help cooling by having the coolant up towards the cylinder heads more.

DD2000 should give you some good ideas of what your going to need if you spend some time on it. To make HP remember you want to get air in & out of your engine as efficently as possible. I would recommend getting parts that are capable of being gasket matched to a Felpro 1206 gasket.

Gkull is running around those 3's I think, maybe he'll chime in here. He's using an open plenum intake so that's something esle to consider ;) .

Keep us informed :cheers:

 

thanks for all the replies, i already have a 2500 stall converter, and plan on getting a different rear end so i really think this engine will rock. i tried usung desktop dyno, and i dont really understand how to use it, to confusing, also what exactly is an open plenum intake and who makes one, im really considering this engine ill tell you how it all turns out
thanks

 

Here are teh Desktop Dyno results (click to enlarge).

461 HP @ 6,000 RPM & 457 TQ @ 4,500 RPM

 

thanks for all the info


:cheers:


[Modified by vette406, 2:24 AM 6/30/2003]

 

THE MONEY PIT you have mail
:D


:party:

 

If you are starting from scratch anyhow, why not get a stroker crank and go to 427 ci? I would suggest using an ARP bolt kit for heads and especially the bottom end, and go with the AFR heads. 406 engines like really big cams.
Sounds like a fun motor that you are building!!! :cheers:

 

Are you building this or some machine shop?

Smoked tires is shooting for 600 hp with @ 20 less ci. It's very easy to do with 91 octane pump gas.

The rule is: The higher flowing heads you have the less cam duration it takes to make a certian power level

Also roller cams make more power with less duration than the equivolent flat lifter cam.