Welcome to Bob’s Blog! This is where Bob will post tips, tricks, and experiences he has with other racers. Check back often to read what Bob has been up to.

Methanol Safety Tips

Friday, July 15th, 2022

Methanol fuel is very popular in motorsports.  It is common in drag, circle, and boat racing for example.  It is readily available and reasonable in price.  It has favorable properties as a racing fuel such as wide tuning window and good tolerance to high compression or high boost.  However, it is a hazardous organic compound in vapor or liquid states as well as in mixtures with other liquids.  That hazard is misunderstood by many who race with it.

Methanol Safety Information Source

Screen shots are provided from our tech manual, 5000 Horsepower on Methanol, to illustrate some of the safety issues:



Added info on safety issues are highlighted in our methanol fuels publication:

  • more info about unhealthy exposure from skin contact
  • more info about unhealthy exposure from fumes and fume accumulation
  • flammability
  • corrosion.

Methanol Fuel Safety Examples

Several of our racing contacts through the years indicated medical problems from methanol exposure.  Recently we conversed with some methanol racers with medical problems who were unaware of the effects of methanol exposure.

Note: It is reported that there is variability in skin absorption characteristics between different people.  Some are more susceptible to medical problems from skin absorption than others.

For example, I am particularly sensitive to methanol exposure.  Any time I had even a small amount of racing methanol on my hands or a splash on my arms or legs, I would get a splitting headache within 5 minutes.  Some others around me did not seem to have that sensitivity.  Rubber gloves, sleeves, and long pants became a common part of my pit clothing.  Also, safety goggles were soon added to protect my eyes. 

Occasionally in the pits, a passerby with a lit cigarette or cigar would walk up to watch or talk.  I did all I could to keep a distance from them or stop until they put out the light.

Team Boddie @ Sacramento Raceway July 15 & 16, 2022 event announcement

Thursday, July 14th, 2022

Team Boddie promod drag racing; again at Sacramento Raceway. on Sat & Sun, July 15-16, 2022.

Air Density / Density Altitude / Grains of Water for racing engine tuning from ADO

Air density, track MAP LOCATION:

Air Density METRIC units, MAP LOCATION:

Air density FORECAST:

HISTORICAL air density example: &

Sacramento Raceway (916) 363 2653

Team Boddie website link

Motorcycle Drag Racing at Sacramento Raceway, California

Saturday, May 21st, 2022

Unlimited to street bikes drag racing with various other events for a weekend event.

Unlimiteds include blown nitro harley, blown nitro japanese, nitro harley, …

weather forecast by the hour:

Fine Tuning Article

Thursday, May 19th, 2022

Our latest air density tuning article:

Subtle Variations Can Make a Big Difference in a Racer’s Tune-up

FI High Speed Bypass

Sunday, March 20th, 2022

Our latest article all about the high speed bypass:

High Speed Bypass: Greater Control in Mechanical Fuel Injection Racing

FI Fuel Pump Ratings

Monday, January 24th, 2022


Mechanical fuel injection uses a positive displacement fuel pump to load the jetting distribution system.   Proper fuel pump size and jetting is vital for good performance and good spark plug readings.

In the past, Hilborn fuel pumps were rated by the manufacturer at 1,800 RPM fuel pump speed.  Enderle, Kinsler, and most other fuel pumps were rated at 4,000 RPM fuel pump speed.

As a result, Hilborn pumps rated at the slower speed would appear smaller.  Yet, when they were run at higher RPM, they were comparable in size to other manufacturers.


Most installations gear or belt drive the fuel pump to 1/2 engine speed.  A Hilborn fuel pump at 1,800 RPM would correlate to an engine speed of 3,600 RPM.  Other fuel pumps rated at 4,000 RPM would correlate to an engine speed of 8,000 RPM.  The later 4,000 / 8,000 RPM combination is commonly used as a standard by most MFI flow bench services world wide.


A 20 GPM fuel pump for nostalgia nitro racing would be at an engine speed of 8,000 RPM.  Many of the competitors gear the wheel speed on these racer cars to run higher engine speeds.  Over 10,000 RPM is common.  The same 20 GPM fuel pump flows upward of 25 GPM at the higher RPM.  Fuel mixtures for the class running over 85% nitro produce a lot more power at the higher operating RPM.

Technical: About 50% of the combustion is stoichiometric.  About 50% is monopropellant.  As engine speed is increased, the monopropellant portion of combustion increases, and power goes up.

REFERENCE: Fuel Injection Racing Secrets, Blown Nitro Racing on a Budget.


One of our friends is currently developing a very high pressure fuel pump for MFI using an industrial design.  The purpose is greater atomization such as what occurs in high pressure gasoline direct injection as well as diesels for highway use.  We will update as more info is produced.

Fuel Injection Bypass Circuits

Monday, November 22nd, 2021

Racing mechanical fuel injection jetting is made up of nozzles to the engine and one or more bypass pathways back to the fuel supply.  The positive displacement fuel pump with the jetting layout makes a linear ‘fuel curve’ with engine RPM.  That is, the fuel to the engine per revolution is essentially constant.  As RPM goes up, fuel goes up.  Typical fuel pumps are usually bigger than necessary.  Tuning is done by changing one of the bypass circuits.  That is done to reduce or increases the fuel bypass for one of several different purposes.

Main bypass

The main bypass is the most common one used for tuning.

>> A bigger main bypass is used to reduce engine enrichment

>> A smaller main bypass is used to increase engine enrichment.

Idle bypass

Most fuel injection systems use an idle bypass.  It is enabled at low throttle positions.  It bypasses extra fuel for the idle needs where the throttle valve is closed down.  Only a small amount of air is going into the engine.  Only a small amount of fuel is needed for idle.  The idle circuit shuts down as the throttle is opened.  That is to deliver the full amount of fuel to the engine at full throttle.

High speed bypass

A high-speed is used to provide an added bypass for various functions.  For a normally (naturally aspirated) racing engine, it is commonly used to open at high engine RPM.  That reduces fuel per revolution.  That is used to match the engine fuel need.  In a normally aspirated engine, that usually goes down at higher engine RPM because of a reduction in volumetric efficiency at higher RPM.

For a blown engine, older blowers would lay down at high speeds.  The high-speed bypass was used in the same manner.  It would open at higher RPM to reduce fuel per revolution.  That would match the declining fuel need with the blower that would pump less air at higher speeds.

The high-speed bypass can also be used for extra fuel enrichment at the low end to reduce power.  Drag racing with a torque converter may benefit from that.  Power reduction on the hit can help to avoid tire spin on the launch.

Pump relief bypass

Some FI barrel valves are equipped with an added bypass circuit for pump pressure relief.  That is usually only enabled at low to mid throttle positions.  When the throttle is partially closed at high RPM, the fuel pump is delivering a lot of fuel.  However, the barrel valve is closed down.  Without pump relief, the fuel pressure can go too high.  This circuit is disabled at mid to full throttle.

6,000 HP on Methanol

Thursday, September 9th, 2021

Our 5000 Horsepower on Methanol tech manual features specs on some very high output methanol racing engines.  A 6,000 horsepower combination is detailed on p. 132. It is based on a top fuel drag racing V-8 long block with two stage compressors.  A minimum fuel pomp size is 32 GPM at 4000 pump RPM.  Boost is 7 atmospheres.  At a mechanical compression ratio of 10 to 1, approximately 0.23 cubic inches of fuel volume occupies about 4% of the combustion chamber volume at top dead center.  Going up in boost with more fuel pump can yield 12,000 horsepower also featured in this section.

Several 5000 horsepower combinations are described in Chapter 28 including Gene Sharber’s tractor pulling two stage turbo methanol engine combo gets 110 psi manifold boost.

Other high output engine combos are featured in appendix 29.  highlights are the GM Ecotec drag racing 4 cylinder at 1,450 HP and Smokey Yunick’s 209 ci turbo small block pulling 1,200 horsepower for the Indy 500  We thank GM Corp and Carbon press for insider details of these combinations.