Installing Indy 8-71 Blower Kit - Divine Wind
Injecting A 500-inch Big-Block with Boost
From the August, 2004 issue of Mopar Muscle
By Marko Radielovic
Photography by Marko Radielovic
Indy Cylinder Head's 500-inch...
Indy Cylinder Head's 500-inch crate motor is normally spec'd with a pump-premium-friendly 10:1 compression ratio. In this blower application, a more appropriate 8.25:1 Wiseco piston is specified. The solid Comp Cams grind features a wide 112-degree lobe separation angle (LSA). An excellent Holley 950-cfm HP vacuum secondary carburetor was the fuel mixer of choice.
We all know the formula for making big power. it goes something like this: compression, cam with duration as long as your arm, expensive high-flowing cylinder heads, big fuel-swilling carburetors. But the list doesn't stop there. Factor in the high-octane race fuel (read: expensive), a higher-than-practical stall torque converter, deep gears to accommodate the heads, cam, and carb, oh, and lousy street manners to boot. But fret not, as there is a way to make full-time, obscene, gut-wrenching power without sacrificing streetability on the altar of the speed gods, and that way is the way of the supercharger.
The former Holley Road runner...
The former Holley Road runner project spun the rollers of the Dynojet to the tune of 436 horses at 5,500 rpm and 468 lb-ft of torque at 4,000 rpm (see dyno results chart) through an 18-spline Hemi four-speed and a 3.54-geared Dana 60. This engine would undoubtedly make more power if it had been equipped with a larger header, as the 171/48-inch units were deemed too small for such an application. The Muscle Car Restorations-built Road runner is one of the cleanest cars the Mopar Muscle staff has ever had the pleasure of laying our mitts on.
Indy Cylinder Head needs no introduction to the Mopar faithful. They have recently expanded their already mind-boggling assortment of heads, intakes, and crate motors to include supercharger kits created in conjunction with the Blower Shop (to be sold separately or as an option on their already stout crate engines). We had the chance to witness one of Indy's 8-71 blower kits installed on the Holley Road Runner "Project M" that was already sporting a stout 500-inch Indy crate big-block. The entire installation and subsequent dyno testing was performed on Horsepower TV that aired in March. Such a combination produces mind-numbing power, fat torque, great drivability, and unrivaled reliability all on available pump premium gas. Hell, we are so confident in its reliability that we are going to be driving this beast of a Plymouth on Hot Rod magazine's Power Tour this year with a similiar blown powerplant. That's a 1,500-mile round trip that will test the merits of Indy's creation. Stay tuned.
• Mopar Performance (MP) wedge Mega Block - 10.69-inch deck height
• Eagle forged 4.150 stroke crank
• Eagle H-beam rods
• 8.25:1 Wiseco forged dished pistons
• Comp solid cam with 250/260-degrees duration at .050-inch valve lift, .534/.555-inch lift
• Indy 1.5:1 ratio roller rocker arms
• Milodon 8-quart street/strip oil pan
• Indy dual-plane intake manifold
• Indy aluminum 440-S/R heads
- Super mod port and polish
- 2.19/1.81-inch intake/exhaust valves
- 295cc intake runners (Max Wedge-sized port)
Indy's blower kit consists...
Indy's blower kit consists of a Blower Shop 8:71 supercharger, Indy blower manifold, drive pulleys, blower belt, carburetor plate, fuel lines, linkage, and all necessary gaskets and fasteners. Carburetor choice is made by the buyer.
Indy Cylinder Head builds a number of Hemi and wedge crate engines to suit anyone's needs from mild stock displacement street engines to multicarbureted big-inch thumpers. Indy is a one-stop shop. This particular gem of an engine displaces 500 ci, 8.25:1 compression ratio (ours was spec'd to run a blower, so the 10:1 pistons were not utilized), a moderate Comp Cams solid flat-tappet cam, and an Indy dual-plane intake manifold. Able to produce over 400 lb-ft of torque at a basement-level 2,500 rpm and featuring 8.25:1 compression and aluminum cylinder heads, one would have to possess a single-digit IQ to induce detonation. To say that this wedge would make a great street engine would be an understatement of epic proportions.
After performing the dyno...
After performing the dyno test with the single four-barrel in place, we quickly removed the intake to make way for the iron lung.
Indy's intake manifold features...
Indy's intake manifold features Max Wedge-size ports and runners. The big-block Mopar lends itself to a truly easy blower installation as the distributor doesn't need to be removed, and there is no water in the intake manifold. Our RB was equipped with an Indy-manufactured valley pan making intake swaps a snap.
The blower kit comes with...
The blower kit comes with a pulley combination that yields a 1:1 ratio, meaning the huffer is neither under-driven nor over- driven, resulting in 8 to 10 pounds of boost. The lower crank pulley is installed at 125 lb-ft of torque, while the six retaining bolts of the blower pulley get torqued to 25 lb-ft.
Prior to installing the blower,...
Prior to installing the blower, the case needs to be filled with gear lube. loosen the idler assembly with an Allen wrench. Next, swing the idler out of the way to gain access to the oil filler hole. Remove the plug and fill the case with gear lube. In this instance, we used Royal Purple Max Gear lubricant and then used Teflon tape on the pipe plug before resealing the case.
We "prestaged" the blower...
We "prestaged" the blower on the upper core support so as not to induce any unwanted slipped discs, hernias, or other stress-related ailments. These things are heavy!
As with many roots blower...
As with many roots blower kits, this one comes with aluminum studs to mate the blower to the intake manifold. The aluminum studs were designed to stretch and break in nitro applications, where explosions are fairly commonplace. Here Ken Lezzari torques the blower studs down to 12 lb-ft. It is also a good idea to use antiseize on the threads.
The idler assembly is used...
The idler assembly is used to adjust belt alignment and tension. In order to adjust tension, a fixed point is picked (in this case the belt's passenger-side edge) and measured. Next, the belt on the driver'side is pulled outward, and the amount of play is measured. Adjust the idler until you are able to move the belt only 31/44 inch. The belt will get tighter when the engine gains heat as the parts expand.
500ci Indy Crate Motor
On 500ci Indy Crate Motor
The carburetor plate gets...
The carburetor plate gets bolted to the top of the blower case using a screened gasket. Not only does the gasket provide a seal, it also prevents loose parts and debris from working its way into the blower and wreaking havoc.
A pair of Holley HP blower...
A pair of Holley HP blower carburetors (rated at 750 cfm each) were perched atop the supercharger. The carbs were used out of the box with no modifications and performed flawlessly.
The aesthetic appeal of a...
The aesthetic appeal of a roots-style blower is second to none. The Blower Shop sets up their street superchargers with billet end-plates, anodized rotors, Teflon seals, and more case clearance for street use.
With all the right hand tools...
With all the right hand tools (nothing exotic is required), anyone with basic mechanical skills is able to install Indy's blower kit in the comfort of their own garage. Also, Chrysler's fantastic RB motor lends itself well to making the swap from normal to pressurized aspiration.
The throttle linkage and fuel...
The throttle linkage and fuel lines are manufactured by Enderle. The fuel lines are prebent stainless steel with AN fittings and provide not only perfect function, but also clean routing.