The great equalizer in most combinations tends to be the use of pump gas and its inherent limitations. By limitations we are referring to the dreaded detonation syndrome that rears its ugly head for a variety of reasons. Most times it leads back to too much ignition timing and/or too much boost and high inlet air temperatures. If you run pump gas you have to decrease the timing, drastically drop the inlet air temperatures, or reduce the boost. One easy fix could be to dump the pump gas and go with some sort of high-octane gasoline or E85.
Easy is one thing but practical is another as adding race fuel or E85 can’t be that simple—high octane gasoline has to be purchased in a drum and gets rather expensive. E85 is cheaper than 93-octane but the availability at gas stations can be scarce in many parts of the country. The Midwest seems to be littered with E85-equipped stations, as are some pockets of the Northeast. The rest of the nation, however, seems to fall short in its distribution making E85 not much of an option for a daily driver. So what choices does a person have available to help get the most from their combination, specifically a supercharged or turbocharged one? The answer is methanol injection. It is a supplement that cools the charge and offers a higher octane rating thus allowing increased timing and boost levels.
This issue we turned to a methanol injection kit from Snow Performance in order to tame a supercharged LS3. The Snow Performance kit is activated under boost conditions only and the methanol is sourced from simple windshield wiper fluid. The company also offers its own methanol mixture dubbed Boost Juice if you prefer to use that product instead of windshield wiper fluid. Our goal was to take a heat-soaked engine and test it two ways, first without methanol and then follow-up with the Snow Performance meth kit on full-boogie. We hit up Race Proven Motorsports (RPM) to find a suitable candidate for a methanol-injection system. Our stipulations were simple; get us a supercharged Camaro that runs on 93-octane pump gas. The choice was easy for RPM proprietor Fran Schatz as his guys had just finished modifying a 2012 Camaro SS convertible. The parts list for the new Camaro ‘vert included a Harrop HTV1900 (essentially an Eaton TVS 1900 rotor package), custom RPM camshaft, and a complete American Racing Headers system that includes long-tube headers, x-pipe, and after-cat exhaust.
A Roots-style supercharger like the Harrop is an ideal candidate for methanol injection because it is notorious for generating a lot of heat under severe driving conditions. An air-to-water intercooler is located in the lower manifold, but it can only handle so much abuse before inlet air temperatures soar. This is not meant to be a negative attribute to Roots superchargers, or any forced induction for that matter, but rather a reality of life outside of a controlled environment of a dyno room (chassis or engine dyno). Every combination falls prey to heat soak and the Snow Performance kit is touted as eliminating that problem—we were about to find out after its simple installation that took about four or so hours to complete.
The ’12 Camaro spun the Dynojet at the Delaware-based shop to a best of 572-rwhp, but that was with a cooled engine and iced down supercharger. A new baseline was established that would better reflect an engine with heat-soak. Our goal wasn’t an excessive amount of heat in the engine, but enough that this wasn’t going to be a hero run. That meant warming up the engine by going through some gears, cruise it for a little bit, and then letting it idle for a little longer. It would put heat in the engine as well as heating up the liquid for the water-to-air intercooler. The heated liquid would be less effective under boost, basically simulating a chance encounter on the street after a brief bench racing session.
Our heat-soaked ’12 Camaro produced 553-rwhp with a torque output of 495 lb-ft at the wheels. The air inlet temperature reading at the beginning of the pull was 82 degrees and by redline it had increased to 105 degrees. The ECM showed ignition timing anywhere from 13-15 degrees and the Harrop supercharger produced a rather mild 6.39 psi. We’d like to note that the Harrop was installed as it was shipped and RPM does have some different supercharger pulleys on order to increase the boost to 10-12 psi, but that is a story for another day.
The Snow Performance kit was turned on and Roshan Patel, lead calibrator at RPM, had programmed it initially to activate at 4 psi of boost but not to exceed 70 percent spraying capacity. This was done so he could make some check out runs to ensure the system operated properly. The first few test pulls proved fine and Patel added some more timing. By the time our chassis dyno testing was completed the LS3 had 16-18 degrees of ignition timing, a full three degrees more than the baseline. Air inlet temperature readings started at 82 degrees, but only nudged up to just 86 degrees by redline! That is a four degree increase while boost pressure showed a max of 6.81 psi. The extra timing netted a gain of 42-rwhp bringing total output to 595-rwhp. The torque experienced a similar increase with a gain of 34 lb-ft at the peak torque reading, as the max rear wheel torque is now 529 lb-ft.
The Snow Performance kit reduced the inlet air temperature by nearly 20 degrees and allowed the use of 3 more degrees of ignition timing. Dropping the inlet temp and increasing the ignition timing kept the ’12 Camaro running smoothly on pump gas and making more power. And who doesn’t love more power?
1. The LS3 has only 350 miles on the odometer as the car was delivered right from the dealer to Race Proven Motorsports (RPM) for modification. It has a mild camshaft from RPM, complete American Racing Headers exhaust front to back, and the Harrop supercharger.
2. Harrop HTV 1900—its Australian for TVS 1900.
3. The front wheel comes off and the liner removed to gain access to the windshield wiper fluid reservoir.
4. The reservoir unbolts easy and you should drain the fluid into a bottle so it can be reused later.