Raw data can vary wildly between dynamometer test setups and settings. This article explains how we collected the data we used to generate our published engine horsepower and torque graphs.
These graphs are found on each of our rebuilt engine pages.
To begin with, all of the data was collected from the same exact setup. All tests were conducted on the same vehicle with the same intake, exhaust, and fuel delivery systems. The GW-EFI engine management system we used was the same one that was transferred from one engine to the next. On top of that, all the tests were performed within a two-week period in the same place. GoWesty is at sea level near the Pacific Ocean where the ambient conditions are very stable.
The first engine we tested was a good running, low mileage, and all-original 2100cc waterboxer with Bosch Digifant injection. We measured the output at the drive flanges using a Dynapack hub-mounted dynamometer. We compared the raw data we collected to the well know VW-published engine specs, which were naturally different because our test method was not exactly the same as how VW arrived at their results. We assumed the VW specs were accurate and came up with a conversion factor of approximately 1.3:1 to match those specs. This same conversion factor was used to convert our raw data to a number that could be directly compared to the VW published specs.
In all, we published the results of these four engine/EFI combinations:
1) Original 2100cc with Digifant
2) GoWesty 2200cc with GW-EFI
3) GoWesty 2300cc with GW-EFI
4) GoWesty 2450cc with GW-EFI
5) GoWesty 2700cc with GW-EFI
We used the data collected multiplied by our conversion factor to generate these graphs:
It should be noted that our goal was to get our GW-EFI replacement parts component system and all our GoWesty engines to pass the same exact emissions testing that VW had to pass back in 1990, which they were required to do to obtain CARB approval to sell the vehicle in California (and by default, the rest of the USA). We could have easily chosen more aggressive igniting timing and/or fuel mixture targets to get better power numbers. We could have published data from tests without the 50 state legal cat that we know costs some power. But any of that would have resulted in unacceptable emissions that not only would fail emissions tests, but also are simply not good for the planet.
You might see advertised all sorts of higher-than-original performance claims from other water boxer engine and/or engine management systems/parts suppliers. Whether or not the claims are true (some are downright silly), one thing is for sure: Only GoWesty went through the time and expense to actually pass the required tests and obtain a CARB executive order (EO) number for the products we sell, making them 100% legal to sell in all 50 states!
Yeah: GoWesty’s got your back!