406 Build..Suggestions?

[balljoint]

says 18" of 2" exhaust pipe right? no equalizer

[clark]

balljoint- please explain more..?

[balljoint]

just sayn the rules sound pretty restrictive.

stock intake, log exhaust with 2" tips? why go for 6800?

Keep it simple man

Maybe some of those mentioned pistons

13-1 cr to keep it simple

comet crank with honda journals

k-1 rods

camcraft

I would run some ported 305 heads. hit the short side radius. 45-50 lbs lighter than Darts etc.

with an aluminum stock quad intake (25 lbs lighter than cast).

and shoot for 6500 TOPS

get the car to turn and it will be all the motor you need. plennnty o'power

I have some ported logs if interested. LOTS of time involved

[racer69]

I run some big asphalt classes. I have found lots of 2 bbl power. A good 4412 comes on quick. If your running a high bank track good power is nice but needed to run up front. If its a flatter track its real easy to over power the track. I used to make that mistake a lot years ago.

Here is one major important thing to remember with a 2bbl. The larger the engine the lower rpm you need to peak at. In another words if your gonna run a little 358 you can open it up and run hog stuff and crank the daylights out of it! If your running a 421 you need to focus on torque and runner velocities so you make your power around 6000-6500.

Here's a little proof.........I run at the high banks at SALEM Speedway. We all run between a 4.56 to a 4.71 gear(rules limit us at 4.71). We also run the Kimmel series. At Salem in the Kimmel race we must run a 3.50 gear and a 5000 rpm rev limiter from msd. One of guys was amazed when he turned a better lap in Kimmel setup than open and with out the alum wall we run! He runs a 415 ci.

I will be running a 358 with monster heads and a 4.71......dyno run last week at.....hahha well lets just say wow!

[dynoman14]

I am sure not running angle plugs will trip up most folks.

What fuel can you run and how much compression?

With no high-rise on the intake what are your legal choices? Can you run the chevy marine iron intake?

I would search out an old set of straight plug Pro-Action heads ( New Zealand manuf. ) if you can find them you will be 50HP ahead of the rest. If not, I would go Dart Platinum 49cc and get them in straight plug. You will be pretty close to the Pro and way cheaper.
As far as pistons go, I think prep and sizing are critical to the life of them I have used both Icon and Mahle in Limited engines that made close to 600HP and turned 8200 with no problems. I would replace them every season and for sure run to the richer side of fuel and lower side of timing 34-36* with race gas, 32-34* on pump premium. I start those engines out with a 57 Champion heat range so they are pretty cool compared to most.

[Master X]

Racer69- you say you made big power with monster heads on a 358 2bbl? Im a little confused cause I thought everybody had been saying not to go to big or it would be really lazy?

[stockcar5]

big heads can make good dyno numbers but they do tend to be lazy on the track. that can be good or bad depending on the track. if its real slick lazy motors may help some guys hook up.

[clark]

Rule Changes...

Ok I hate to beat a dead horse, but new rules just came out and they are much more open then the years prior. We can now run ANY steal head, headers, any cast iron or aluminum intake, but if we run an aluminum intake it is a 50 lb penalty. We can run roller cams, but can take off 50 lbs if we don't run one. Headers with the 50 lb penalty. We are still on the Holley 4412 though, it does not state it must be stock though. My question is, is it worth adding weight to run a roller cam, aluminum intake, and headers on a what would be 3200 lb street stock on asphalt? Or is there a better cast iron intake manifold that is worth running with the sportsman II heads I have now? Also, we are now allowed to run MSD, is it worth switching from the pertronix hei to an MSD set up? And will a stock 400 block with splayed caps hol dup, or is it worth upgrading to a Dart SHP block for this build?

[Dirt Knife]

piston info

4 4032 2618 SRP pistons made from 2618 wrought aluminum alloy are designed for higher performance applications such as FlyWeight or domed highcompression pistons. These environments necessitate the higher tensile strength 2618 aluminum alloy. Physical Properties of 2618 Nominal Density 2.81 g/cc .100 lb/in 3 Mechanical Properties of 2618 Tensile Strength, Ultimate 440 MPa 64,000 psi Tensile Strength, Yield 370 MPa 54,000 psi Modulus of Elasticity 74 GPa 10,400 psi Fatigue Endurance Limit 125 MPa 18,000 psi SRP pistons that are made from 4032 wrought aluminum alloy are designed for street/strip applications utilizing compression ratios that are compatible with pump gas. These pistons also provide a quieter engine on cold start-up. Physical Properties of 4032 Nominal Density 2.68 g/cc .097 lb/in 3 Mechanical Properties of 4032 Tensile Strength, Ultimate 380 MPa 55,000 psi Tensile Strength, Yield 315 MPa 46,000 psi Modulus of Elasticity 79 GPa 11,400 psi Fatigue Endurance Limit 110 MPa 16,000 psi Coefficient of Thermal Expansion 2618 aluminum expands approximately 15% more than 4032 aluminum, thus the 2618fs initial piston-to-wall clearance has to be 15% greater. This difference is most noticeable during a cold engine start. When cold, the 2618 piston can rock back and forth producing a slight noise (sometimes referred to as until the aluminum expands. Both types of aluminum have approximately the same clearances once the pistons have expanded and the engine is running at operating temperatures. Temperature Range Average Coefficient oC oF ƒÊm/m K ƒÊin/in oF 20 to 200 68 to 392 23.2 12.9 Coefficient of Thermal Expansion for 2618 Temperature Range Average Coefficient oC oF ƒÊm/m K ƒÊin/in oF 20 to 200 68 to 392 20.2 11.2 Coefficient of Thermal Expansion for 4032 PISTON FEATURES Fully CNC machined dome, dish, or flat top Symmetrical valve pockets fully radiused Machined oil drain back holes (not slotted) CNC diamond turned skirt Pressure fed pin oilers Forged side relief Honed pin bore Full floating wrist pin Double spiro locks SRP PISTON MATERIALS EXAMPLE: When measured at room temperature, a 4 inch diameter piston made from 4032 measures 4.000h. If the same were measured at 375o, the piston would measure 4.0034h. EXAMPLE: When measured at room temperature, a 4 inch diameter piston made from 2618 measures 4.000h. If the same piston were measured at 375o, the piston would measure 4.004h.



2 me as far as your rules go

take the 150 LB weight penalty run the roller cam alum intake and headders
less nose weight on the asphalt more to add left side

[DaveBauerSS6]

What size track? If its, small tight corners, mod to low banking, I would keep all the weight breaks. Then spend some money on opened up manifolds and high rocker ratios. Get the most out of the compression on that build. Worst case I would opt for headers for 50#.

[DaveBauerSS6]

One more point. The guys adding more power will also be adding more weight. Their setup will change alot. Longer learning curve.