Belly Tank Build Diary

[Mike Brown]

I attached a screen shot from the data with front wheel speed (great data) rear wheel speed (crappy data) and engine RPM (great data). 

[Mike Brown]

We were invited to the Hilton Head Island Concours.  It was a great event.  We were one of twenty cars invited to the "Chairman's Parade".  A little taxing idling a mile land speed car around for the parade, but we made it.  We also won top honors in the "Competition Vehicle" class.  I spoke with the chairman, and they were excited to have a land speed car and would entertain more of these cars. 

[Mike Brown]

The belly tank was also included in an article with Hemmings.  The car is near the end of the article.  The link, https://www.hemmings.com/stories/highlights-from-the-hilton-head-island-concours-saturday-car-club-showcase/

[Mike Brown]

Bob Boberg from eClassicAutos also interviewed me at the show.  The link is, https://www.youtube.com/watch?app=desktop&si=szUwlt024C3H0cCF&embeds_referring_euri=https%3A%2F%2Fwww.eclassicautos.com%2F&source_ve_path=MTM5MTE3LDE2NDk5LDI4NjY0LDE2NDUwNCwxNjQ1MDY&v=2cNTRDdIAGE&feature=youtu.be

[Mike Brown]

My goal is to improve the "squishy" brakes on the lakester.  They always stop the car, but they have been squishy from the beginning.  At this year's PRI show I spoke with Wilwood representatives.  They thought that there could still be air trapped in the lines even though they have been bled many times (before each event).  The lines do go up and down a few times where they go through the firewall and where the flexible hoses attach.  I purchased "T"s that have female double flares on each end a 1/8" npt on the top.  These are typically used to add a pressure switch for brake lights to brake system.  The Wilwood bleeder fittings have a small bleeder (1/4" wrench size) with a 1/8"npt body.  I will add these in about halfway in the run to aid in bleeding the brakes.  The other comment was that the dual 1-1/8" bore master cylinder may not have enough volume to activate four 1-3/4" calipers with four pistons each.  The only 1-1/4" bore master cylinders that I can find are for trucks and they are huge.  Potentially modifying one of these master cylinders to fit may be an option if adding these additional bleeders does not help. 

[Mike Brown]

I am preparing for the May ECTA event in Arkansas.  I needed fuel.  I have been using VP MS109 reg, which is a highly oxygenated race gas with MTBE.  It makes great power and works well with nitrous.  I was buying it locally from Premier fuel.  They stopped distributing for VP but I was able to buy it at the track.  The track supplier will not be at this event so I went searching.  I called my tuner and he agree that I could use Sunoco 260GT Plus as long as I checked my A/F ratio before making a full pass.  There are a couple of dealers for Sunoco.  It turns out that neither fuel was in stock and would need to be shipped in.  Fuel is in the hazardous material category, so shipping is expensive.  I ended up with my standard VP MS109 reg coming FEDEX from Tennessee.  I was able to get a discount code for the fuel bringing the fuel cost below $100 for five gallons but shipping was $85.  It may be time to look at alternatives as long as they work with nitrous since I don't want to add a second fuel system.  This has been a frustrating to say the least. 

[Mike Brown]

Looking to increase traction on the big end I considered adding wing.  Winglogic makes a very nice extruded wing and supplies data on its performance.  I purchased a section for evaluation. 

[Mike Brown]

The downforce chart shows an estimated 800 pounds of downforce at 200mph.  Note that this is on a 65" wide wing attached to a car.  In my application I can only have a 44" wide wing.  I was told that the downforce could not be extrapolated in a linear fashion 44"/65"=.677 or 541 pounds of downforce.  Most "experts" indicated that the downforce would be less but could not derive the amount with the information provided.  This would help a lot with traction if the drag would be reasonable.  Note that to keep the same weight on the front tires the wing would need to be attached ahead of the rear axle.  The moment arm of the wing will cause the drag to impart a lifting force on the front wheels.  Calculations would be required to offset this force with percentage of downforce generated from the wing to maintain safety in steering control. 

[Mike Brown]

The drag chart shows that it will take 120 additional horsepower with the wing at 200mph.  If the drag function was linear it would indicate 82 additional horsepower with the narrower wing.  At the recommendation of the folks at Winglogic I joined a Facebook group called Professional Awesome Racing Technical Forum.  I got lots of feedback but nothing pertinent to my application.  Meanwhile looking at the traction issue from another vantage point I ran 221.44mph at Loring without traction issues on M&H DOT drag radials.  The drag radials ended up with scallops on the sidewalls and I replaced them with NASCAR style circuit racing tires from Hooiser.  These tires do not have the same contact patch as the drag radials and that is when my traction issues began.  I began researching DOT drag radials again.  While researching I found that Mickey Thompson voids drag radial warranties are void if used on a chassis dyno.  I then began to debate about the cause of the drag radial failure, was it on the track or the dyno.  During tuning sessions my car spends longer periods of time on the dyno than on the track.  To add to the complexity the car must be strapped down tightly to keep the tires from slipping.  The car is also static with no cooling air going around the tires.  I did not inspect the tires or check for temperature when on the dyno, but I do at the end of the run on track.  The tires have never been over 150 degrees F at the end of a run.  It may be prudent to purchase a set of Mickey Thompson DOT drag radials for evaluation.   

[Mike Brown]

My Optima red top battery is weak and needs to be replaced.  I was exploring alternatives to find out that the Optima BCI group 34 battery is about an inch shorter than any other group 34 battery.  When I built the battery box it was designed around the Optima battery.  I don't want to modify the battery box so I will replace it in kind (with a yellow top as recommended by the Optima guys at the PRI show).  Live and learn. 

[Mike Brown]

I am going to try the Mickey Thompson DOT drag radials.  I was running up against the red line of the engine, probably from tire slippage.  If nothing else they are a little taller which will give me higher speed for the same RPM as the Hoosiers. 

[Mike Brown]

I have also decided to eliminate the enclosure around the cockpit and change to a much smaller fairing behind it. 

[ronnieroadster]

I have also decided to eliminate the enclosure around the cockpit and change to a much smaller fairing behind it.

What you have now uncovered is what's called the oil rig.  A very good fellow Sid who has helped me enormously with aero improvements told me years ago to cover the cage AKA the oil rig and add the fairing rearward covering the engine. Each improvement Sid has suggested has helped my gain MPH without any more horse power. Since my engine is just a little Ford flathead under 300 inches burning gasoline the horse power output is well below what I had been told was needed to run 200 MPH.  We have run over 200 many times setting records along the way that's with the oil rig being covered.
Ronnieroadster

[SPARKY]

Have you considered the type of dyno that uses rear wheel stud to drive it

[SPARKY]

also   there may be some advantages to slightly squishy brakes,   I learned the hard way of what happens with a reaction hard brake pedal jab  it locked up my rear brakes   I changed it to a smaller master brake piston where I had to do one extra brake pump to get a full pedal