We imagine it was a big deal when aluminum intake manifolds first became available to hot rodders because the cast-iron stuff they were working with before was terrible for performance. This material change alone was worth horsepower. The aluminum was significantly lighter in weight than cast manifolds, but was also a better dissipater of heat, the enemy of horsepower. These days, you'll notice most OEM intake manifolds are made from a composite material for those same reasons. Using that knowledge, and seeing an opportunity to offer benefits that conventional small-block fans had not seen in the aftermarket, the experts at Air Flow Research came up with a trick two-piece intake that operates like a ported-aluminum manifold, but uses O-rings instead of gaskets and it's about 10 pounds lighter.
The Titan TXR (PN 4801) and TXS (PN 4802) intakes caught our attention at Performance Racing Industry show in Orlando, Florida, last year, and we thought it would not only work great on the blacked-out 427ci small-block we have cooking, but we also wanted to test it out in the real world. Mike Morgan's budget beater Nova was the test mule, since his car, despite being a mighty rough specimen, has always been a steady 6.80-6.70 runner in the eighth-mile with a 410ci small-block.
In the following pages we show off how the Titan is installed, but we also put it to the test at the dragstrip. We admit we didn't perform the most scientific test for this piece due to varying track temps and conditions, but we did, however, look for an increase in mph on average from the car's last time out with the aluminum intake. Morgan has had hundreds of passes in his car, so his assessment of how the engine performed with the Titan is good information for all.
If you are in the market for a ported intake manifold for your racer, or you just want a trick plenum on your streeter, then you'll want to look into the AFR Titan piece.
1. Installation of this setup starts with a composite baseplate.
2. This part seals to the cylinder heads at the coolant crossovers using green rubber O-rings. The orange strip is a Viton piece that seals the bottom of the intake top.
3. The coolant crossover uses threaded brass inserts that need to be held with a wrench before being tightened. Failure to do this can lead to a cracked intake leaking coolant.
4. Here is a shot of the TXS intake top for the Titan intake manifold (PN 4802). You have three plenum choices for the Titan setup; a dual plane (DPS) and a taller single plane (TXR). This piece gets bolted to the composite baseplate and seals to the head using black Viton O-ring gaskets.
5. Before fastening down the base, these steel inserts are used to strengthen the area around the bolt, preventing cracks due to over tightening. The holes to bolt down the base are elongated to accommodate engines that have been milled or decked a whole lot. Our test engine had the heads milled quite a few times over the years, but we were still able to cinch it down.
6. Dual pattern distributor provisions feature reinforced steel plates for increased rigidity around that area. The distributor hole also gets an O-ring.
7. AFR includes this industrial strength clear silicone to seal the ends of the intake as well as where the O-rings meet when the top is installed at the base.
8. Once the base is bolted down, the TXR (or TXS) plenum can be screwed down using six Allen head stainless fasteners that thread straight down. This feature allows the user to easily swap between plenums if desired.
9. AFR also now offers composite carb spacers to complement the Titan, but also work to help airflow in any single plane application.
10. For the dragstrip testing we opted for a pair of 28.5x10 drag slicks from Phoenix Drag Tires. These ensured we’d have consistent runs and eliminate tire spin as a variable as best as possible.
11. The engine we’re working with is a 410ci small-block with older-style AFR heads that have been extensively ported to flow 330 cfm at 0.700 lift. The camshaft is a hefty mechanical roller and the carb is an out-of-the-box Holley 4150 with 830 cfm.
12. Last year this 410ci combination ran an average of 6.72 at around 102 mph in the eighth-mile with a ported cast-aluminum intake, so we were pleasantly surprised when Morgan’s Nova laid down a 6.64 at 103 mph in the first outing, a 6.72 at 104 mph on the second run (spinning), and a clean 6.54 at 104 mph (1.40 60-foot time). This was with the TXR top, which we determined was best matched to the engine’s high rpm (7,800-plus). We had the option to try the others and in the eighth-mile, maybe the smaller, torquier plenums would work better. What’s cool is with this manifold you have the option to test out that query without too much hassle.
13. Even after a long night of racing, we noticed the intake manifold was still only warm to the touch, whereas metal intakes would be scalding.
- Composite plastic construction operates 30 degrees cooler than aluminum manifold
- Weighs 9-11 pounds less than aluminum (depending on model)
- Cast-in nitrous bosses
- Modular design with interchangeable runners
- Dual distributor hold-downs
- Reduces carburetor vibration by 5 percent
- Rubber Viton gaskets
- Includes distributor clamp and hardware
- Available in dual plane (DPR), short single plane (TXS), and tall single plane (TXR)