January 2008 Newsletter for Rear Wheel Drive Models
Page 4: Tuning for Horsepower, adjustable cam gear, perfect power 6

One of the best parts of my job is getting calls and emails from all the guys/gals out there tuning their Volvos. I love the questions, you get a real sense for what people are doing and the obstacles they run into. One of the commonly repeated questions I get is around adjustable cam gears. Typically it’s one of two questions, “Where should I set it?” and “How much horsepower can I expect?” My answer to both those questions are “It depends” To clarify lets take a closer look at what an adjustable cam gear does and how to maximize the benefits, then we can better determine where to set it. An adjustable cam gear when used on a single over head cam engine like Volvo’s four cylinder red block engines (B21, B23, B230) will allow you to adjust the power delivery from an engine in relation to RPM. All engines have a sweet spot where the hit their max power delivery, an adjustable cam gear allows you to move this sweet spot, as well as the rest of the power band, around to suite your needs and desires.

A Non turbo B230 engine will have more power between idle and 2500 RPM than a turbo model due to the higher compression ratio. Once the turbo begins to spool and make power the turbo car will then have more power above 2500 RPM than the non turbo car. Depending on how you want your car to perform (drag car, drifter, touring car) you can tune to your taste. So here is an example straight from my garage. My 1986 740 turbo is a slug off the line but when the turbo starts spooling and making power, hang on! So I advanced the cam gear to provide a bit of the power earlier before the turbo starts spooling. If I wanted a touring car or a drifter I might retard the cam gear so that my power band is timed with my turbo spooling, this allows for that push you back in the seat serious acceleration, the kind that makes tires smoke : )

Here’s another extremely important point, once you advance or retard a cam gear you’ll need to reset the ignition timing since it is relational to cam shaft position. This is particularly necessary for cam driven distributors and a good idea in general for side mount distributors. This a common source for the problem of installing a cam gear and getting the feeling like the car lost power. Ignition timing is critical, make sure you know how to set it and have a manual to help guide you through the process. If you need help don’t forget to call, it’s my favorite part of my job!

Our new cam gear provides the edge in performance for your B21, B23, B230 engines (1976-92). Adjustable in 2.5 degree increments up to 10 degrees, either advanced or retarded, and it weighs less than half the factory gear! A fixed single piece, this gear is adjusted by lining up the desired inscribed timing mark with the factory timing mark and placing the corresponding dowel hole on the cam. This should not be confused with ignition timing. By advancing the gear you will gain low-end power at the expense of upper-range power and by retarding the gear you will gain upper range power with a like reduction in low-end power. This gear provides the widest range of adjustment from high RPM turning race engines to the big bore non-turbo motors with lots of low end grunt! Our new gear is hard anodized for long life and tested for durability. A perfect match for our Turbo camshaft or even use it with your stock cam.

ipd’s Perfect Power 6 is designed to allow you to tune both the fuel and ignition system of your electronic fuel injected Volvo. As exhaust, intake, and turbo systems are changed or upgraded, the vehicle’s fuel and ignition needs change too. The ipd Perfect Power 6 allows you to modify the ECU signals on maps found within the unit and with windows software to gain optimum efficiency, maximizing the power that your upgraded parts can yield. An average installation consists of connecting six wires to the vehicle’s original wiring loom, installing the software onto a PC, and starting the tuning process! The Perfect Power 6 also includes numerous useful features such as:

• 6 amp injector driver for extra injectors
• Selectable trigger points to control engine fan, shift light, etc.
• Proportional solenoid control for nitrous or intercooler spray systems
• Dual selection maps
• Launch control
• Real time engine tuning, no need to ‘save’ then ‘upload’
• Data logging Fuel & ignition maps with 128 sites each

Installation can be done in about two hours and some minor soldering is required. You'll also need a PC with a com port for the tuning process.