First of all, let me say that I’m not the only NSX owner that has gone down this path…I just wanted to share my experience. Also, if you are looking for high horsepower numbers – don’t bother reading on.
I own a 1992 NSX with the Comptech “high-boost” set-up, AEM engine management, RC 550 injectors, Walbro fuel pump, Comptech headers and exhaust. The results on an SAE corrected dyno showed 352 RWHP after AEM tuning. I was suffering the same woes as many CTSC owners – extremely high intake air temperatures, in excess of 260 degrees under load. I also installed the new AEM serial gauge so I could monitor those temperatures, as well as check my overall boost and air fuel ratios.
I looked at many of the intercooler alternatives posted on Prime, as well as talked with the guys that tuned my car – their backgrounds are turbo Mustangs, Firebirds and Honda Civics, all with high horsepower…the Mustang runs 8.10’s in the quarter with drag radials…nothing to laugh at.
Their suggestion was to try water/methanol injection. Armando (MiamiNeSex) has successfully made close to 470 RWHP with his BBSC, and the Aquamist set-up, along with a great tune, so I knew the system worked. The question was, what would happen with an older style CTSC and a maximum of 8lbs of boost?
I decided to try a system put together by Snow Performance. It was considerably less expensive than the Aquamist version, and it was made in the U.S. vs. England. The kit consisted of a high output pump, two different sizes of jets for applications up to 635 hp, a boost activated electronic pump controller, a 2quart reservoir, and an optional low liquid LED indicator. Everything necessary to install the kit was included…all connectors, tubing, and fittings. The only thing I fabricated was a small plate made from a large fender washer, which was used to mount the nozzle assembly to the rubber intake before the throttle body. I sandwiched the rubber between the fender washer and a flat thin brass nut that I loctighted on the inside of the intake. Boost to trigger the controller was taken from a "T" off the vacuum line to the fuel pressure regulator.
I ran wires for the two supplied LED’s to the pillar mount I used for the serial gauge – red for low fluid and green indicates when the injection pump comes on. The reservoir was mounted in the trunk, along with the boost controller and pump. There is an empty, four-spade connector in the trunk, just behind the driver that is normally used for the optional phone. I used two switched circuits – one for the pump and the other for the boost controller. The entire installation took about three hours.
Once installed, I scheduled another trip to the dyno. An initial run was made to verify original results…which were almost exactly the same as when I left the dyno. The boost controller was set to have the pump come partially on at 3lbs of boost, full on at 4lbs all the way to 9lbs.
A second run was made to check the pump settings. Everything worked perfectly. The pump lowered the intake air temps by more than 90 degrees. We ended up advancing the timing 3 additional degrees, made some slight air fuel adjustments and made another run. The goal was to achieve some gains in horsepower, but more importantly , keep the intake air temperature down. Final results were a small gain ( about 10 RWHP) in overall horsepower, but a substantial gain in midrange (18 RWHP), with similar gains in torque – a good thing if you track your car. Peak boost was 8.5 lbs at 5,000 rpm and boost dropped off to 5.5 lbs at 8,000 rpm, which is probably why the overall gain in horsepower was so small. Overall, I was expecting a greater horsepower increase, but we kept the timing conservative, and the air/fuel was no higher than 12 – so I’m sure more was available, and a tighter supercharger belt may have also helped. What is impressive is the consistent 90 degree lower intake air temps, which is important in the summer Florida temperatures. And, so far I’ve driven about 200 miles around town on the set-up and have used about a pint of the water/methanol mixture – so keeping the tank full does not seem to be a factor.
From Snow Performance site:
Why Water/Methanol Injection?
The Boost Cooler® is Snow Performance’s latest generation water/methanol injection system. The primary function of water/methanol injection is to provide “chemical intercooling”.
In gasoline engines, as with any intercooler, this suppresses detonation so more power producing boost and timing can be utilized. Water, with its high latent heat of vaporization cools the intake charge and combustion. Methanol cools the charge and combustion but also acts like an extremely high octane fuel (some researchers claim as high as 120 octane) as well as adding more oxygen to combustion.
In diesels, the effect is three fold: 1. The intercooling effect provides for more available air and all the benefits of a higher positive pressure ratio (more power giving fuel can be utilized safely without high combustion temperatures). 2. The combustion of water provides for more power on the power stroke. 3. Methanol acts as an additional fuel for more power.
A brief History:
Water injection was evaluated scientifically in the 1930’s by H. Ricardo who demonstrated that one can basically double the power output of an engine using water/methanol. The first widespread use was during WWII on supercharged and turbocharged aircraft. In 1942, the German Luftwaffe increased the horsepower of the Focke-Wulf 190D-9 fighter aircraft from 1776HP to 2240HP using 50/50% water/methanol injection. The allies soon followed by fitting the P51 Mustang and other high performance aircraft with water/methanol injection. Following the war, the turboprop aircraft industry used water/methanol injection and called it the “automatic power reserve system (APR)” for use in hot or high altitude take off. It surfaced again in the 60’s when GM used a system on the OEM turbo Corvair. It was used effectively in Formula 1 before being banned for adding too much power.
The latest competitive use is in World Rally Racing (WRC) where virtually all teams use it in some form and in diesel truck/tractor pulling competition. It is important to note that in the fall of 2004, the long standing world record in the quarter mile for diesels was broken twice (now 7.98 sec) by two different vehicles; both using the Boost Cooler® water/methanol injection system by Snow Performance.
If you’d like more information or would like to see photos of the installation, feel free to PM or e-mail me at [email protected].
Mark Youngquist
I own a 1992 NSX with the Comptech “high-boost” set-up, AEM engine management, RC 550 injectors, Walbro fuel pump, Comptech headers and exhaust. The results on an SAE corrected dyno showed 352 RWHP after AEM tuning. I was suffering the same woes as many CTSC owners – extremely high intake air temperatures, in excess of 260 degrees under load. I also installed the new AEM serial gauge so I could monitor those temperatures, as well as check my overall boost and air fuel ratios.
I looked at many of the intercooler alternatives posted on Prime, as well as talked with the guys that tuned my car – their backgrounds are turbo Mustangs, Firebirds and Honda Civics, all with high horsepower…the Mustang runs 8.10’s in the quarter with drag radials…nothing to laugh at.
Their suggestion was to try water/methanol injection. Armando (MiamiNeSex) has successfully made close to 470 RWHP with his BBSC, and the Aquamist set-up, along with a great tune, so I knew the system worked. The question was, what would happen with an older style CTSC and a maximum of 8lbs of boost?
I decided to try a system put together by Snow Performance. It was considerably less expensive than the Aquamist version, and it was made in the U.S. vs. England. The kit consisted of a high output pump, two different sizes of jets for applications up to 635 hp, a boost activated electronic pump controller, a 2quart reservoir, and an optional low liquid LED indicator. Everything necessary to install the kit was included…all connectors, tubing, and fittings. The only thing I fabricated was a small plate made from a large fender washer, which was used to mount the nozzle assembly to the rubber intake before the throttle body. I sandwiched the rubber between the fender washer and a flat thin brass nut that I loctighted on the inside of the intake. Boost to trigger the controller was taken from a "T" off the vacuum line to the fuel pressure regulator.
I ran wires for the two supplied LED’s to the pillar mount I used for the serial gauge – red for low fluid and green indicates when the injection pump comes on. The reservoir was mounted in the trunk, along with the boost controller and pump. There is an empty, four-spade connector in the trunk, just behind the driver that is normally used for the optional phone. I used two switched circuits – one for the pump and the other for the boost controller. The entire installation took about three hours.
Once installed, I scheduled another trip to the dyno. An initial run was made to verify original results…which were almost exactly the same as when I left the dyno. The boost controller was set to have the pump come partially on at 3lbs of boost, full on at 4lbs all the way to 9lbs.
A second run was made to check the pump settings. Everything worked perfectly. The pump lowered the intake air temps by more than 90 degrees. We ended up advancing the timing 3 additional degrees, made some slight air fuel adjustments and made another run. The goal was to achieve some gains in horsepower, but more importantly , keep the intake air temperature down. Final results were a small gain ( about 10 RWHP) in overall horsepower, but a substantial gain in midrange (18 RWHP), with similar gains in torque – a good thing if you track your car. Peak boost was 8.5 lbs at 5,000 rpm and boost dropped off to 5.5 lbs at 8,000 rpm, which is probably why the overall gain in horsepower was so small. Overall, I was expecting a greater horsepower increase, but we kept the timing conservative, and the air/fuel was no higher than 12 – so I’m sure more was available, and a tighter supercharger belt may have also helped. What is impressive is the consistent 90 degree lower intake air temps, which is important in the summer Florida temperatures. And, so far I’ve driven about 200 miles around town on the set-up and have used about a pint of the water/methanol mixture – so keeping the tank full does not seem to be a factor.
From Snow Performance site:
Why Water/Methanol Injection?
The Boost Cooler® is Snow Performance’s latest generation water/methanol injection system. The primary function of water/methanol injection is to provide “chemical intercooling”.
In gasoline engines, as with any intercooler, this suppresses detonation so more power producing boost and timing can be utilized. Water, with its high latent heat of vaporization cools the intake charge and combustion. Methanol cools the charge and combustion but also acts like an extremely high octane fuel (some researchers claim as high as 120 octane) as well as adding more oxygen to combustion.
In diesels, the effect is three fold: 1. The intercooling effect provides for more available air and all the benefits of a higher positive pressure ratio (more power giving fuel can be utilized safely without high combustion temperatures). 2. The combustion of water provides for more power on the power stroke. 3. Methanol acts as an additional fuel for more power.
A brief History:
Water injection was evaluated scientifically in the 1930’s by H. Ricardo who demonstrated that one can basically double the power output of an engine using water/methanol. The first widespread use was during WWII on supercharged and turbocharged aircraft. In 1942, the German Luftwaffe increased the horsepower of the Focke-Wulf 190D-9 fighter aircraft from 1776HP to 2240HP using 50/50% water/methanol injection. The allies soon followed by fitting the P51 Mustang and other high performance aircraft with water/methanol injection. Following the war, the turboprop aircraft industry used water/methanol injection and called it the “automatic power reserve system (APR)” for use in hot or high altitude take off. It surfaced again in the 60’s when GM used a system on the OEM turbo Corvair. It was used effectively in Formula 1 before being banned for adding too much power.
The latest competitive use is in World Rally Racing (WRC) where virtually all teams use it in some form and in diesel truck/tractor pulling competition. It is important to note that in the fall of 2004, the long standing world record in the quarter mile for diesels was broken twice (now 7.98 sec) by two different vehicles; both using the Boost Cooler® water/methanol injection system by Snow Performance.
If you’d like more information or would like to see photos of the installation, feel free to PM or e-mail me at [email protected].
Mark Youngquist
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