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Old 11-23-2006, 10:28 AM
Rick WI Rick WI is offline
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These are the general rules we build our street stocks to for the tracks we run on. If you build to the exact letter of the rules you are going to end up making around 300 or so HP. This class is very competitive here in WI and some racers are willing to dump some significant dollars to make power, not unlike our Late Model series racers. The two areas where the power is made is tricks we have found in cylinder heads, the 052's, and lots of time on the cam doctor designing lobe profiles. Carbs have not been a source of major power. Those are teched pretty well so even a full blown Braswell carb is going to be only worth a couple, if that, HP as compared to a stock 4412. The carb spacer and type of "stock" intake though can really help out.


ENGINE -- Engine must be of same manufacturer as chassis and body. Maximum of two valves per cylinder. No Aluminum blocks or heads. Maximum displacement 362 cid (Chrysler products 373 cid). All engines must meet following specifications regardless of manufacturer; Stock or stock replacement cast iron untouched heads (no porting, polishing, acid dipping, or gasket matching allowed) required. The only stock replacement heads allowed are World Product SR 1052 #4266B and #4267B. Minimum combustion chamber 62cc, maximum 2.02-inch intake and 1.6-inch exhaust valves required. Valve spring retainers are the only titanium parts allowed. Flat top pistons required. A minimum of zero deck height required. Maximum 10.8 to one compression ratio. Steel connecting rods only. No Bowtie, Vortec or 18 degree heads allowed on GM products. Roller tip rocker arms allowed. A 3/4" inspection hole in oil pan required. ]nspection hole must be located in line with second or third rod journal of crankshaft, on either side of pan and above sump area (oil level). Hole in windage tray in line with inspection hole required.

CAMSHAFT & IGNITION -- Hydraulic cam only. Maximum lift at valve: GM-.480 inch, Ford/Mopar-.520 inch. No solid lifter or roller cams allowed. Stock type (HET) ignition components only. Any coil permitted. NO MSD boxes or duel-point distributors.

CARBURETOR -- Stock Unaltered 500 CFM Stock Holley 4412 2 bbl. Or I 3/8" Rochester allowed on all cars. $200 claim on any carb at any time (after racing event) by any competitor in Sportsman Division or management. No alterations except removal of choke "Butterfly" allowed. 1 1/4" maximum adapter/spacer plate allowed. Double return springs. Air cleaner required to act as flame arrester. No air induction boxes or ram air units allowed. Steel fuel lines required, remote fuel filter allowed.

INTAKE & EXHAUST MANIFOLDS -- Completely stock passenger car 2-bbl.. cast iron intake and exhaust manifolds required. No grinding, polishing or altering allowed. No Bow-Tie manifolds, internal heat riser crossover must remain in place. Center dump and log style manifolds allowed. Max exhaust manifold inside diameter 2-inches No cast iron header style exhaust manifolds allowed.

EXHAUST SYSTEM -- Maximum diameter 2 1/2" before collector and/or muffler, 1 1/2" maximum diameter behinds muffler. Exhaust must exit left or rear (not right side) and behind driver. Effective mufflers required, Collector or muffler must not be located forward of transmission, tOO-decibel limit measured from front row of bleachers. No car expelling flame, smoke or backfiring will be tolerated

Casper, no need to feel stupid. No matter what you do or how you do it I am sure you will have fun at the track once you start. If you don't want to spend a lot of money on the engine just build a stock 355 and bolt it in. Take the extra time to learn about setting up the chassis and practice whenever possible. No matter how much HP your motor is making if you can't roll through the corner and it doesn't hook coming out you are dead meat.

Bolting on a part that doesn't conform to the rules and is obvious, like mentioned, will get you in trouble. They can claim the part and will toss your points. If it's a gray area they may simply say don't show up again with that setup. Tech folks generally can catch the obvious violations so fully worked carbs, weight violations, incorrect head castings, intake castings, displacement errors and compression issues will get discovered. If the folks down your way are like those up here many of the top racers are pushing the rules. I suspect they know the tech officials and know what they know and what they don't know, then work the rules to their benefit. The better engine builders will certainly know what it takes to pass tech.
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