A BluePrint 383 Stroker and Gearstar 700-R4 Breathe New Life into a Tired C10
The time had finally come for us to bust out one of our oldest projects—to take our long abandoned ’69 Chevy C10 off of the back burner and get it back on the road. While the suspension was previously attended to, the beyond-tired 250 inline-six and three on the floor still remained. It was high time to make a decision on a drivetrain.
We have waffled many times on what would be the best engine and transmission combo for this truck. The original idea for this project was to build a simple, ’bagged truck that could be driven daily while putting some impressive numbers down at the local track day. This is still the plan, with the “simple” part of the equation becoming more and more important. With the amount of late-model trucks we tinker with on a daily basis, a simple-as-can-be swap with minimal electronics was sounding better and better.
In a conversation with BluePrint Engines, we came to the conclusion that they had exactly what we needed, in stock and ready to ship, in the form of their own 383-inch small-block that comes dressed and dyno’d—the one we had our eye on made 440 horsepower! This engine setup more than fulfilled our simplicity, power, and driveability requirements and got the ball rolling to get this truck back in action.
In our search to back the mighty mouse, we looked no further than Gearstar Performance Transmissions for a 700-R4 that was built specifically to match the specs of the engine along with the gear ratio and tire size we’re going to run. Like the engine, the trans was shipped to our door and was ready to run. Check out the first installment of our new project, and check out the websites to see what BluePrint and Gearstar have to suit your needs.
Here is a look at our ’69 C10 after its final voyage with its stock drivetrain. This particular model came from the factory equipped with a 250 inline cylinder and a three-speed manual transmission. This third-gen inline six-cylinder engine made only 171 hp new, and by the way it drove into the shop, we’re sure it has lost a step or two over the past 46 years of service.
We’re yanking that engine right out and donating it to one of our sister publications, Super Chevy, for them to have some fun with.
Although it’s not required to do so when conducting an engine swap, we wanted to clean the engine to make it worthy of our new components.
We removed the front clip and scrubbed down the firewall to allow us to cover it with some Chassis Black paint from Eastwood.
This made us feel a lot better about dropping the new engine and transmission package into place.
Since we’re starting with a six cylinder manual transmission model we needed to make a few changes to the engine and the transmission mounts. This engine mount and transmission mount package available from Performance Online (POL) made things simple.
First, we unbolted and removed the factory engine mounts.
The POL engine mounts were a straightforward replacement, as the mount holes corresponded with the factory six-cylinder engine mounts.
We also had to cut and beat out the factory manual transmission crossmember. Soon we’ll show you how we fit the transmission cross member into place.
Blueprint 383 CID small Block PN: BP3834CTC1 Specs: HP & Torque: 420 hp/450 lb-ft
Compression Ratio: 10.0:1
Flat Tappet Cam
Cast Steel Crank
Four-bolt main, one-piece rear main seal
Align-honed main bearing bore
Cylinders honed on computer-controlled machine to within .0002 straightness and roundness
Cylinders are sonic tested for thickness
New cast steel crankshaft
Chevy heavy beam rods with 150,000-psi bolts
Hastings moly rings
Melling high-volume oil pump
Hydraulic flat-tappet cam
Heavy-duty double roller timing set
BluePrint Performance aluminum
Hardened retainers and springs
2.02 swirl polished intake valves
1.60 swirl polished exhaust valves
BP Aluminum Head PN: H8002K
Cam Type: Flat Tappet
.480 Intake .486 Exhaust
229 Intake / 230 Exhaust duration at .050
34 degrees total at 3,500 rpm
10-15. Is it possible to have the best of both worlds when it comes to reliable horsepower at an affordable price while shopping for an engine package? The answer is yes, and the poster child of this theory is BluePrint Engines’ GM-based 383-cid small-block engine. What does “GM based” mean, you ask? Well, the engineers at BluePrint engines researched all the tricks that engine builders have been using on the venerable 350-cid small-block Chevy engine when they transform them into a 383 stroker engine. This tried-and-true combination has been a racing favorite since the early ’70s as engine builders fit a 400-inch model crankshaft into a 350-inch block, thus increasing the displacement from 350 ci to 383 ci. The package worked very well at the time, as most made 1 hp per cubic inch, which gave it the nickname of “the square engine.” Today’s modern technology has allowed engine builders to push the envelope in building more horsepower than ever dreamed of from the early pioneers of speed, as most of the math has remained the same, but more importantly the quality of the parts has become more reliable allowing for the engine builders of today to seek more power. BluePrint Engines utilize all of the advancements, both old tricks and their own cutting-edge new technology, manufacturing their own vital components right here in the United States. Rather than beginning with a repurposed 350 block from an old GM core, BluePrint manufactures their own engine block, crankshaft, and cylinder heads to meet the high expectations of themselves and their customers. After the machining process the parts go through a vigorous testing process before assembly. Only after each component passed their quality checks is it allowed to be assembled and dyno tested before it’s shipped out to the customer. Horsepower numbers far exceed the old “square number” of 383 hp as the version that we picked from BluePrint’s arsenal of powerplant’s makes a guaranteed 420 hp (our paperwork showed that our particular unit made 440!) and more importantly 450 lb-ft of torque! Here’s a look at their buildsheet to explain more about this awesome engine package.
16. Before we could mate the engine with the transmission, we needed to install the engine’s flexplate that truly connects the engine and transmission together. Due to the fact that the BluePrint engine makes over 400 horsepower, the smart choice is to install an SFI rated flexplate just to play it safe. B&M’s SFI rated flexplate was the perfect choice to fit our needs.
17. We paired it with ARP’s SFI rated flex plate bolts and paid close attention that we installed the flex plate with the correct side facing the engine. After we lubed the ARP bolts, and ran them in the threads by hand, we used this digital torque wrench from Eastwood to tighten all the bolts down to 60 ft. lbs.
18. Next we installed the Urethane engine mounts from POL’s kit onto the engine. Urethane engine and transmission mounts outlive the typical rubber based mounts ten times over, plus they allow the power plant to flex just enough to give the occupants of the truck a smooth ride.
19-23. Can an overdrive transmission hold all that power, and still cruise at a low rpm on the highway? Sure, if it’s built like Gearstar’s Turbo 700-R4 Level 2 package. Gearstar has been around for over 25 years, and every one of Gearstar’s lead technicians has over 30 years of performance transmission build experience for vehicles that are equipped with high-horsepower engines. Only the best components go into Gearstar’s transmissions and every one of them are dyno tested before they’re crated up and shipped out to the customer. When we asked for a recommendation for paring this BluePrint 383 Small-Block engine that is rated at 420 hp, Gearstar’s pick was for us to go with the their 700-R4 Level 2 four-speed or transmission. This will allow us to have a strong package to handle the horsepower that the BluePrint 383 engine is producing, while allowing us to cruise it on the open highway at speed while turning low rpm thus saving fuel. In case you’re curious, here’s a look at the buildsheet of what goes into a Gearstar level 2 Turbo 700-R4 transmission.
Gearstar Turbo 700-R4 - Level 2 -Transmission Specs:
Horsepower rating: 450 (up to 425 lb-ft of torque)
Converter: 12-inch high-performance furnace brazed with flanged hub and carbon-fiber clutch
Master Overhaul kit with high energy frictions and new steel plates
Wide Carbon-Fiber 2-4 band
Transgo Recalibration Shift Kit
New Valvebody Separator Plate
Original Equipment Style Filter
New Torrington Bearings
Thrust Washer Kit
New 29-Element Dual Cage Sprag
New Low-Reverse Spring & Roller
High-Capacity 10-Vane Pump Assembly with New Rotor and Slide
New Vanes and Hardened Rings
0.500 Boost Valve
Updated Pressure Regulator Valve
Extra Capacity 3-4 Clutch Drum Assembly with High-Rev Spring Kit
Hardened Sun Shell
New Original Equipment Steel Transmission Pan
New Speedometer Drive Gear
New Speedometer Driven Gear
20,000 GVW Hayden Transmission Cooler
Vacuum Lockup System
Installation Kit: Universal Fill Tube and Stick, Universal Throttle Valve Pressure Cable, Universal Transmission Mount, Universal Converter Cover (Plastic)
24. While the Transmission was still on the crate, we went ahead and hooked up the transmission’s kick-down cable, plus we installed the filler tube before mating the engine and trans together. This is a much easier way than doing it in the truck.
25. The Transmission that came from Gearstar had the torque converter already installed from their shop and was ready to go when we unpacked it from the create. They do this to ensure that the converter has fluid in it to prevent a dry start-up, and that the converter is properly engaged in the pump.
26. Now it was time to mate the transmission with the engine and balance it on the hoist. You’ll note that we didn’t bolt in the converter to the flexplate at this time; however, we will need to do so, or the vehicle will never move on its own power.
27. Setting the engine into place was a snap as the POL mounts were already bolted up and waiting.
28. Before we installed the transmission crossmember we wanted to be positive that the engine was spaced evenly between the framerails and pointing straight back. After we double-checked the measurements we slid the POL crossmember into position, and began drilling through the framerails.
29. After all eight holes were drilled, we ran Grade 8 fasteners between the crossmember and the framerails.
30. Finally, we ran in the Grade 8 fasteners into the POL urethane mount. With the new drivetrain securely in place, this was a good stopping point for this month.
31. And there we have it, an affordable yet potent 383-cid BluePrint engine, backed up by a Gearstar turbo 700-R4 transmission, held in place by a set of POL engine, and Transmission crossmembers. Stay tuned as we dress the remaining accessories to make this tired C10 into a street fighter.