9.47 at 148
Intro 11.18, 128.56 10.74, 135.6 10.24, 135.99 10.11, 136.97 10.00, 136.89 9.94, 139.1 9.82, 145 9.47, 148
I lost count of the number of "Booms" somewhere along the line, but it became quite clear (finally!) that the deep dish pistons were probably too weak for the level of boost rammed at them by the ys-trim. Engine dude Mike Blackstone doesn't care much for AFR heads, but the option of 76cc chambers meant that the piston reverse dish could be much smaller than the -31cc we were running with the LT1 heads. I had a chance to buy a set of AFR 220 LT4 heads with GTP porting, so I grabbed them.
The engine buildup is covered on another page, so I'll cut to the chase. The new combo is making some power! Despite a PCM that would not let the engine rev beyond 6800, the car made back-to-back sub-9.50 second passes. The pic below left is an Excel graph of data recorded by my Dynojet Wideband Commander air/fuel ratio meters showing the RPM stumble that felt like a rev limiter.
Changes since previous best in red.
Engine (385 cu in - 4.045" bore)
Acceleronics Impedance Converter and 95 lb/hr Delphi low impedance injectors
Vortech ys-trim supercharger, 66 tooth cog crank pulley, 29 tooth blower pulley, Spearco air/air intercooler
AS&M 58mm throttle body
AFR 220cc LT4 heads, 76cc chambers
Ported by Mike Blackstone in Concord, CA
T&D shaft rockers, ratio is "bigger than 1.6" ;-)
Smith Brothers tapered pushrods
GM LT4 intake, ported by me
Custom grind solid roller cam
intake: > 225 deg duration, > 0.650" lift
exhaust: > 235 deg duration, > 0.650" lift
Cloyes 9-3145 double row timing chain and gears
Meziere electric water pump, BeCool radiator
MSD Digital 7 ignition box, MSD 8251 coil, MSD 8.5mm wires
JetHot long tube headers, two 3" Carsound cats, 3" Blaine Fabrication y-pipe, 4" Mufflex cat back
Lunati 3.75" crank, Lunati ProMod 5.85" rods, blueprinted by Mike Blackstone
CMP 4.045" reverse dome blower pistons and file-fit rings
Moroso steel 3rd-gen f-body oil pan, Melling 10555 pump
MBA billet MAF ends
Fuel
See Fuel Delivery for 1000 hp for pump and fuel line details
95# injectors from Acceleronics
Acceleronics Impedance Converter
Drivetrain
Coan 4000rpm stall converter 4500-stall, 9"
Mark Williams 3" chrome moly 'shaft, MW 1350-series u-joints, MW pinion yoke
KTRE 12-bolt rearend, 3.42 gears, Tom's Differentials BOE posi and heat treated ring 'n pinion
Suspension
HAL shocks, 1LE springs and antiroll bar in the front (end links disconnected)
stock coils, 1" solid antiroll bar in the rear, Bilstein shocks
BMR chrome moly LCAs and panhard rod with poly bushings all 'round
BMR chrome moly torque arm, poly bushing
Wheels/tires
front: 26x4.5 ET Fronts on 15x3.5 Weld Drag Lites
rear: 28x10.5W ET Drags on 15x10 Weld Drag Lites
ARP studs on all corners