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Topic Review (Newest First)
11-23-2006 10:00 PM
Rick WI Have fun Casper.
11-23-2006 09:19 PM
Casperdude898 thanks for the advice it really helps a lot
11-23-2006 03:50 PM
Rick WI There are two reasons you don't want to piss away a lot of money on fancy pumps and stuff like that. First, it may not be legal. Second, if it is legal all the buddies around you that you are racing tend to hit each other. One smack in the wall and you'll be shelling out a lot of dough to replace those parts. So no, it's not an area you'd want to put your money in.

When someone comes in and wants to get into racing we'd steer them to a nice car that is for sale. By nice I mean one that we know is setup for the track they want to run on and handles well. Spending the money up front on a car that is well sorted out I think is the best investment. You will most likely have a spec on the tires you will have to run and fresh tires are a plus. Good shocks are also a plus but there will also be a spec on these. Spec meaning the rules will dictate the type/style.

On the engine, yes keep it simple. The first year you will be learning the ropes. Not having a ton of power will help you learn the car and work on what it likes and doesn't like.

Claiming is a rule that allows another racer to "claim" parts off your car. The purpose of the rule is to keep trick hidden stuff, or obvious for that matter, parts out of the car. Lets say you build a super trick motor with all the lightest and best bottom end components. A racer could have $3000 in crank, rods, pistons, coatings. If a claim rule exists where another racer can put up $1000 for the guys motor, the logic is folks won't build that stuff. Claim rules though are seldom if ever used in our area. The reason is if one person does it, the next week they can, and will be claimed. Plus whoever does it will probably get the crap beat out of him in the pits.
11-23-2006 10:56 AM
Casperdude898 would it be a good idea to make everything electric (fans water pump fuel pump etc.) or is there something about dirt track that u dont do none of that to and i was wonderin exactly wat is "claiming" a part?
11-23-2006 10:19 AM
Casperdude898 so i shld just get a plain stock motor and not worry about pushin the specs. thanks a lot for the help and that saves a lot of money and time on my part for now.
11-23-2006 09:28 AM
Rick WI 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.
11-23-2006 07:08 AM
barnym17 what exactly does the carb rule say? some 500 based 2bbls can be made to flow way more than the stock rating depending on mods allowed.You said the rules were cast intake and exhaust manifolds 400 h.p will be a good mark to start with you can step up later.Now with that being said if you are just starting out a good reliable engine is far more important than all out power.A 355 with vortec heads flatops and small hydraulic cam that will run at a reasonable rpm with good tourque AND NOT BREAK every time you turn around will allow you to concentrate on learning to drive and set up the car.what is the tire rule beleive it or not it can be hard to hook up 300 horsepower on a dry slick track with small tires.And after you figure out setup and driving then upgrade the engine.
11-23-2006 02:22 AM
Blazin72 The average power for the class is going to vary depending on the tracks rules and limitations. As RickWI mentioned though, they can be capable of 400hp. If you're running illegal parts the very least they're going to do is tell you to make it legal. At our local track you'll forfeit your points up to that point in the year and not allow you to race until you make it legal.
11-23-2006 01:18 AM
Casperdude898 well im just tryin to get into dirt track racin do yall kno what the average hp is in a street stock? and wat happens if i build something "illegal" and they figure out? (this website makes me feel really stupid but thanks a lot for the help)
11-23-2006 12:15 AM
Blazin72 Rick, your cars are running almost 400hp on two barrels? That's impressive. What other restrictions do your cars have? The cars in the Hobby Stock class at a track near my house can run any size engine as long as they're all iron and run iron intakes and factory iron exhaust manifolds. There is a $1000 claim but nobody abides by it. I've got a 350 in the car I'm working on and I'm going to get my butt kicked by all of the 383s and 400s most other racers have out here.

Casper, as far as your question goes. Do as the others have already said and drop in the biggest engine you can. Also, I've been told to run lots of compression. If you're limited on compression then run the max allowable amount. The 350 I have now has about 11.9:1 compression but I'm thinking about tearing it back down and shooting for closer to 12.5:1. You're gonna have to run race gas. It's expensive but hey, it's racing and racing isnt cheap.
11-22-2006 10:37 PM
Rick WI You would not be correct, throughout the Midwest you'd be in last place with a 305 against our class rules 350 motors in Street Stock. I suspect Ark is no different, you'd be a back marker.

A 305 would make a lousy race motor. Bore is WAY too small.

We build lots of Street stock, limited late model, late model and dirt modified motors and have done so for years.

If the class rules let you build to 356 that's what you want to shoot for. If you can run a 400 and stroke it down to that size, use super lightweight cranks and get a 1500 bobweight that's what I suspect some of the top engines are in your class. Within our class rules and within the tech inspectors abilities to inspect our top street stock motors are running just shy of 400 HP SAE on the dyno.
11-22-2006 09:30 PM
carsronnie i would use the biggest engine i could. you know the old saying.
11-22-2006 09:17 PM
Casperdude898
dirt car question

would a 305 be a good dirt car motor (street stock)to me it seems since u can only use a 2 barrel 500 cfm carb it wouldnt smother a perf. built 305 as much as if u were putin it on a performance 350 givin it kind of an advantage but am i right in a way?

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