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You can download a 6 page index of terms from “5000 Horsepower on Methanol”. You can also download an index of names from this publication as well. Check the shopping page.

ALREADY AN OWNER: These indexes will help to find page numbers for various topics in the manual; such as octane, nitro, temperature, air to fuel ratios, and many others.

CONSIDERING A PURCHASE: These indexes reveal the extent of coverage and the broad range of topics throughout the publiication.

We are revising our Server source for more reliable viewing. That should be done by the end of the week. If you had problems shopping or ordering, call (916) 419 6649 or email (bob@racecarbook.com) for help. Thanks Bob Szabo

The racer is one step closer to setting up a tuning plan for density altitude like we wrote about throughout our technical manuals; the racer can log onto www.airdensityonline.com and get current air density and density altitude for many race sites throughout the US; and soon density altitude forecasting for your day before planning. When we raced, we would look up the weather forecast and manually calculate density altitude for the following day, using the math in our tech manuals. That is soon to be automated in the site link.

Dyno results just in from one of our customers on his new twin turbocharged alcohol Big Block: dyno’d 2,500+ HP at 25 psi boost with a turbo setup capable of 50 psi boost. He reports that the most boost that he is currently seeing in the installation is 35 psi, blowing the tires away on the drag racecar.

Question: Different racers get different boost readings often from similar blown engine combinations. Why do some get that high boost reading and others do not?

Answer: Boost reading is also a function of the fuel split. Fuel split is the amount of fuel delivered to the blower hat injector versus the amount of fuel delivered to the intake manifold. That amount of fuel split determines the amount of cooling in the manifold. More fuel in the hat causes more cooling. That causes a denser mixture which then causes a lower boost. It then causes a lower boost reading and not necessarily less horsepower as many are finding out. A lot more information about fuel split is provided in 5000 Horsepower on Methanol. More information about boost readings is in Fuel Injection Racing Secrets.

In our drag racing, we did use air to fuel ratio as a controlled value to get the engine into a linear range. That task is an extensive explanation through out writings. The linear range is where the engine is completely predictable. We achieved that very well in our racing. Once we operated the engine in a linear range, we were able to vary our shift point from a Quarter Jr program predictions to get our drag racing ET predictable. A tuning plan was done the day before an outing. Weather predictions from the internet were used. The Quarter Jr program was used to predict the performance with the various air densities that were predicted over the course of the racing time period. For example, early qualifying was often early in the morning when air density was up. Then later qualifying was late in the afternoon when air density was lower. The different air densities were put into the Quarter Jr. program to get the predicted performance. Shift point was varied to produce the target ET for that air density. In addition I used math that is throughout our writings to determine jetting for the various air densities. Then, with fuel injection jetting and shift point predetermined by the time of day (different air density), I wrote out a plan for jetting and shift point changes. During race day, I simply looked up the time and my tuneup plan, did the changes, and spent the day eating hot dogs, networking with others, and of course, maintaining the racecar. It was a blast and took all the pressure out of tuning on race day. There was simply little to no tuning decisions on raceday. And no engine damage from whops’s.

QUESTION: Do any of your books help in areas of tuning with using O2 sensors? I am needing some what of a baseline for a good tuneup using the correct nozzles, pills to help with getting the most or should I say most consistent in drag race ET’s. Of course everything being the same.

Thanks for replying, R. in Texas

Hi R in Texas,
Thanks for your inquiry. Our Jetting for Racing Mechanical Fuel Injection … book has info on O2 sensors including accuracy limits.

REPEATABILITY VS ACCURACY: O2 sensors are a great tool, however, the accuracy (especially for methanol or ethanol) and repeatability may be issues. Accuracy is less of an issue if they are repeatable. That is, regardless of whether they are accurate or not, you can rely on the reading if they are repeatable. An example would be a speedometer that is out of calibration. You learn how much it is off and drive with that error in mind. If it is jumping around from a binding drive cable, and not repeatable, then it is difficult to gage you speed.

REPEATABILITY: Regarding the repeatability of the O2 sensor method, that is a question. They respond to the condition of the exhaust. Especially if you run methanol or ethanol, I am not sure whether the instrumentation technology with those fuels is fully developed yet. You can have a rich cold exhaust gas or a rich hot exhaust from different air to fuel ratios from different tuning results and I am not sure the O2 readings would be repeatable. Another source of error would be the combination of sensor location and heat soak from prior running.

WITH SOLVENTS: Auto dealers have cautioned in the use of solvents around O2 sensors. That could affect the readings.

OEM APPLICATIONS: In the highway vehicle, O2 sensors are used as a device to steer the air to fuel ratio, not necessarily determine it. And most highway vehicle computer controls include a cold engine warm up default to get through the warm up cycle before relying on the O2 sensor. Rich mixtures of racing fuels along with sensor location may send the exhaust into that range or may not. Just a caution. In drag racing, the variability of engine temperatures is a problem. In circle racing, the engine gets up to a temperature and stays there. Not so in the drags. It starts out cold and warms up on the run. How hot it gets in the exhaust is often dependent on how long you were sitting in staging. That may effect the sensor.

AFR: Air to fuel ratio is extensively explained in our 5000 HP methanol book and also illustrated in our Fuel Injection Racing Secrets book. It is based on pounds of fuel per revolution vs pounds of air per revolution. We go to great lengths to make repeatable methods to determine air to fuel ratio.

AFR & O2 SENSORS: An O2 sensor would definitely help but I am not sure how well it works as a repeatable indicator of the air to fuel ratio as the tuning tool. Consultations with a couple of the manufacturers last year indicated they were not sure either.

All the best,
Bob Szabo

Question: What is pure methanol?
Answer: If it is sold as pure methanol, it is supposed to be well over 99% methanol. It is a baseline compound that should behave the same regardless of supplier unless it is mixed with something else such as a top end lube or it is contaminated. Water is a common contaminant.? There is a difference in NHRA and IHRA fuels test methods for the methanol classes. The fuel you can run at those events is the fuel that passes their fuel test. I am not sure it would necessarily pass a chemistry lab test however. There may be some differences. One of the Kinsler engineers and others have mentioned observing differences from different suppliers, but I am not sure those experiences were with tested fuels.

Congrats to Scott Williamson for great result reported as follows:

“… I raced last weekend at the Jegs Cajun Sports Nationals at No Problem Raceway in Belle Rose La., and I was amazed at the results I had by using the formulas from your books. … I was able to tune my car with confidence and see repeatable results.

I run in Top Dragster and was able to Qualify 5th with a run of 6.49 at 206 mph and had a runner up finish in the Top Dragster Shootout.”

Question: Can methanol be stored for a long period of time?
Answer: Methanol absorbs moisture. So if it is stored, it must be in a sealed container. Plastic is microscopically porous and does allow for methanol moisture contamination if it is stored a long time or (in some cases) if the container is dipped in an ice water bath to keep it cool on a hot day.