Hobrook All Motor Challenge

Each race in All Motor at the Milan Dragway Friday Night Heads-Up Series, we will compute the quickest average during qualifying. The team with the quickest average from qualifying will get $200. At the end of the season we will award the team with the quickest average $1,000 at the Milan Dragway Champions Banquet. Teams must run the decal provided in the designated area

All Motor Engine Packages

Darren Mag races in the All Motor class at Milan Dragway’s Skinny Kids Friday Night Heads Up series. The Liberty Gears All Motor class runs small block cars at 2950 and big blocks at 3350. The cars must be single carb or single throttle body. Cast intakes only [no sheet metal intakes]. Clutchless transmissions must add 175 lbs. No electric or air shifters. Maximum Tire 29.5 x 10.5 (NO W's allowed) Drag Radials are OK they must not be larger than the spec slick. Stock rear suspension and ladder bars are OK. Four links add 75 lbs. Wheelie bars are not allowed. No tube chassis front ends. Stock body panels and glass, with the exception of the sidewindows,rear hatch or rear truck window. If your scoop is forward facing you must add 50 lbs. The interior must be stock appearing with two seats. All cars must use mufflers. And last but not least No Power Adders.

Darren's Program

Chris started with a Dart steel block and performed their typical race prep to it. The Sonny Bryant crank is a 4.090 stroke and 4.185 bore. The 6.125 Carillo rods are topped with 16 to 1 Diamond Pistons with Total Seal rings. Keeping all that lubed up is a Dailey dry sump oil system with a 9 quart Stef’s dry sump tank and pan.
The Blue Thunder 4.3 heads could rate a story by themselves. They are the work of Carl Foltz Engineering. When Tony Stewart won the 2007 Budweiser Shootout at Daytona he used CFE heads. CFE does heads for NHRA, IHRA, and Nascar and has long list of winning customers. These heads gives you Pro Stock technology for Sportsman prices. The splayed valve heads have 2.25” Dell West Titanium intake valves and 1.60 exhaust valves with Manley Next Tech springs with Manley titanium spring and valve retainers. The valve seats on these heads are copper alloy just like the Nascar and Pro Stock heads that CFE does. The Rocker arms are shaft mounted 1:8 Jesel rocker arms. Darren also uses Jesel Lifters and Trend pushrods to keep the valve train moving with the least amount of flex. The heads flow 440 CFM. The engine uses a Competition Cam with over .900 lift. You’ll have to torture or bribe Chris Holbrook if you want more info on the cam or intake manifold.
The rules for Milan’s All motor Class require a cast manifold. Chris cut it into 24 pieces and ported it to match the Blue Thunder 4. 3 cylinder heads and welded it all back together. The phenolic spacers in the plenum and on top of the manifold keep the air/fuel mixture as cool as possible. The manifold wears a sheet metal shroud around it to keep prying eyes away.
Sitting on top of the jigsaw puzzle they call a manifold is the 1600 CFM carb done by Dale at CFM carburetors. The exhaust side of the heads feature custom built step headers by Rich McCarren at Pro Race Craft Engineering. The headers feature three steps 2”, 2 1/8” and 2 1/4” with a 4 inch collector. The mufflers are Flow Master Outlaws.
The ignition is handled by a MSD digital 7 box, MSD distributor and MSD coil. Taylor wires and Autolite spark plugs round out the package. The Tilton Chevy starter has been located on the drivers side with a custom fabbed adapter by Pro Race Craft Engineering. The car has a 3 gallon aluminum fuel cell and uses a Weldon fuel pump and regulator. That combination makes 1080 at 8800 Rpm DTS Dyno.
Darren’s Trans is a basically a Jeep 727 with an 904 internals, adapted to fit a Ford. There is a complex valve body that changes pressure for each gear. The guts are all 7075 machined aluminum straight cut gears. None of the internal components share anything with the OEMs. There are two converters that Darren uses with the trans. They are both A-1 Chevy torque converters, 6400 and 7200 rpm. Joel’s on Joy in Detroit builds lots of transmissions for NHRA Comp Eliminator, Super Stock and Stock Eliminator Racers. The constant feedback from the racers that Joel’s supplies, keeps him on the cutting edge. A lot of the racers would prefer Joel to be their little secret.
The aluminum Dynatech drive shaft sends the power back the Ford 9” Strange Ultra Case with 40 spline gun drilled axles. With the 5.0 ring and pinion, the motor screams through the traps at 9300 RPM.
The rear suspension is a ladder bar setup with a custom anti roll bar. The shocks are Strange double adjustable coil overs. The rear wheels are 15x12 Bogart's with Micky Thompson 29.5 x 10.5 slicks.
The front suspension features double adjustable coil over Santoff Struts with custom tubular A arms and K member. The Stiletto polished “Pro Box” rack & pinion steering system provides the directional control for the 26 x 4.5 in Micky Thompson front tires mounted to the 15 x 3 Weld wheels.

The Results

In 2007 Darren Mag was the number one qualifier in All Motor Class for all of the Skinny Kid's Milan Dragway Heads Up Series. His best time in 2007 was 8.36 at 163 mph.