13. The new box was mounted to the firewall in the passenger side inner fender behind the fender gills. It’s out of the way and hard to notice. We were already using MSD’ 8.5mm Super Conductor wires and a factory-style cap, so we reused the low-mileage cap and wires rather than switching to HEI-style wires and cap that came with the new distributor. We will probably switch at the next tune-up. For the tach, all you need to do is plug the factory tach drive cable into the distributor and tighten the coupler.
14. Once everything was connected, the car was running a whole lot smoother, and there was no dieseling when we shut it off. The car would hold a nice low rpm idle, and didn’t stall when we turned the A/C on—another problem with the original 92,000-mile distributor—plus the factory mechanical tach came to life! Note actual peak torque was 370, not the 383 figure shown. The 383 number is an unexplained spike in the graph.
15. Now the new distributor, along with everything else hooked to the manifold, was taken off so we could remove it. All the intake ports were plugged with rags, the valley covered, then the surface areas were cleaned of the old gasket material.
16. The upper and lower parts of the intake install with reusable rubber gaskets. The intake comes with all the hardware and gaskets you need, including a tube of RTV sealant.
17. We had to plug three of the coolant crossover holes, since we were only using one line on our old school application. We needed a smaller nipple for the coolant line.
18. A 1/4-inch bead of the supplied RTV sealant was applied to the china walls, and at each corner of the heads. There are a few more areas that need a dab or two of this sealant, but that is all mapped out in AFR’s instructions.
19. The lower piece is installed and tightened to 25 lb-ft.
20. Then the seals were installed into the upper portion of the intake.
21. Since we knew it wouldn’t fit under the stock LT-1 hood, we tried the TXR race series upper first. It’s a full inch taller than the street design. This gives the fuel a straighter, longer shot into the intake ports for improved horsepower and torque. It is mated to the lower section with the provided hardware.
22. All the other items were reinstalled without any drama. The engine was warmed up and timed before we made our initial pull on the dyno. After making a few pulls, we were confident she gave all she had. We shut down and swapped out the runners.
23. The TXS upper was pretty easy to change since it splits from the lower. All we needed to swap over was the carb. The distributor and cooling stuff stayed in place. We did have to move the heater hose because the intake is lower than old Stealth manifold, and was interfering with the fuel line, but that was the only small issue. One thing to note was the manifold’s temp: Even after multiple dyno pulls the manifold was fairly cool to the touch, not something you can say about the aluminum piece. Since the TXS is lower than the Stealth intake, we were curious to see how it would do.
24. We had a baseline of 344hp and 368 lb-ft of torque before we added the new ignition, That got us to 350hp and 370tq. The TXR (race) put down 380 hp and 378 lb-ft, adding a whopping 30 hp to the rear tires. Torque was up 8 lb-ft. The TXR bested the Stealth dual plane across the entire rpm range. The TXS was down less than 4 peak hp and 6 lb-ft to the Titan TXR, but up 26 hp and 2 lb-ft to the Stealth at peak. Torque-wise, the Stealth has it below 4,000 rpm, but after that the TXS pulls ahead.
25. All in all, no matter which Titan intake you choose, either is a great option. Had we more hood clearance, we’d have definitely used the race upper, even on the street. The only drawback looks to be the price, which is $581 at Summit Racing, making them expensive in the SBC realm for a carbureted intake. There’s no difference in price between the street and race versions.