Following up on our last issue, we are ready to install our new interior pieces and start the planning phases of our powerplant/drivetrain swap. We have some great goals for this little OBS Chevy truck and with some help from the industry elite, the plan is quickly coming to fruition. The factory 4.3-liter V6 is still pumping out enough power to push this GMT400 down the road, but after close to 25 years in service, it’s best days are behind it. Still bolted to the originally installed transmission, this combo has performed and functioned better than the original engineers probably expected, but it doesn’t meet our standards. After we remove the block and set it aside while we install its replacement, we plan to show you a few simple tips and tricks to rebuilding this still dependable workhorse for a different project down the road. Just because it doesn’t have crazy compression or extremely thick walls doesn’t make it completely useless, especially if you’re just trying to flip an older truck for some extra spending cash.
Our big secret from the last two issues was the engine choice for project Stella. We showed you the crate and you could clearly see the engine builder, but the specifics were kept under wraps, until now. Sure we could have documented a brand new LS-swap or even a 5.3-liter rebuild, but the truck we are working with has been so synonymous with small block Chevy engines over the years that we decided to keep that trend going. The generation that originally loved these short wheelbase, full-size trucks have grown up around 350ci SBC’s and opened up 383’s. So we decided to go back to the basics and order up a Longblock 383-stroker engine from Blueprint Engines.
To transfer the power to the rear axle, we called up the geniuses at American Powertrain for one of their 5-speed Pro-Fit kits designed specifically for 88-98 Chevy/GMC C1500 OBS GMT400 trucks. This kit features the TREMEC TKO 5-speed coupled with all the parts needed to successfully install these transmissions with an excellent shift position for both bench and bucket seat projects. No modifications are required to the tunnel and allows the stock cross member to be reused with only a few holes to drill in the frame, making the install a breeze.
We will start that part of the project in the next issue of Street Trucks, but until then, let’s finish up our interior upgrades and break down all the parts we will be installing.
Our weapon of choice for this weekend warrior is a BluePrint Engines 383CI Stroker Crate Engine. This is a small block GM Style Longblock complete with Iron Heads and a Roller Cam. The engine is fully built and dyno-tested before it shipped. This is a carbureted engine that will produce nearly 420-hp which is almost double the power this little truck currently has.
HP & Torque: 420 HP / 440 FT LBS
Compression Ratio: 9.5:1
Cast Iron Heads
Hydraulic Roller Cam
Cast Steel Crank
Hand picked seasoned block
Square and parallel decked
Align honed main bearing bore
Cylinders honed on computer controlled machine to within .0002 straightness and roundness
Cylinders are sonic tested for thickness
4.000″ Bored .040″ Over
1-Piece Rear Main Seal
Mech fuel pump provision: Yes
Passenger Side Dipstick
Drilled and tapped for clutch linkage
New BluePrint Cast steel crankshaft
OEM type 5.700″ connecting rods w/ 150,000 psi bolts
External Front/ External Rear
Cast iron Vortec heads
1.25 diameter valve springs
Hardened retainers and springs
2.02 swirl polished intake valves
1.60 swirl polished exhaust valves
Cam Type: Roller
.510 Intake .520 Exhaust
230 Intake / 236 Exhaust duration
@ .050 – 110 degree lobe separation
34 degrees total at 3500 RPM
This American Powertrain Pro-Fit kit is designed for 88-98 Chevy/GMC C1500 OBS GMT400 trucks with no cutting of the floor. This transmission will also provide a 30-50% increase in fuel economy from the factory while utilizing low RPM’s during cruising for greatly reduced driver fatigue and an improved highway driving experience. They are also known for creating reduced engine wear which leads to a longer engine life and cooler engine operating temperatures.
AP Revolution Shifter Mechanism to locate the shifter which will fit bench or bucket seats
A seamless DOM Driveshaft Assembly that is Race Balanced with Solid U-Joints
A Cryogenically Hardened Steel Driveshaft Slip Yoke
Polyurethane Transmission Mount
Pilot Bearing – Stainless rollers, grease pre-pak
Reverse Light Harness – Weatherseal
Speedometer Conversion Electronic
Reuses the stock crossmember
5-Speed TKO Gear Ratios – 3.27, 1.98, 1.34, 1.00, 0.68
Engine Pully Kit
Vintage Air’s Front Runner drive system is engineered for maximum Performance First. These are not merely appearance or dressup components. They are the essence of form following function. Designed for Small Block Chevrolet applications with power steering, this kit features a Detroit Speed aluminum power steering pump, machined-finish brackets, a polished compressor and alternator chrome pulleys, and polished clutch and tensioner covers.