Belly Tank Build Diary

[Stan Back]

With all those tire tracks on the beach -- I'da been tempted -- just for the experience.

[Mike Brown]

With all those tire tracks on the beach -- I'da been tempted -- just for the experience.

Stan,

Just to show you how much the temptation was I included a photo of the beach one evening, long wide and hardly any traffic. 

[4-barrel Mike]

Excellent!   

Mike

[Stainless1]

Dang sure wouldn't want to hit a course marker    You might of had to pick a little sand out of your crack
 

[Mike Brown]

The staff at the Texas Mile had a Facebook Live feed going during parts of the day.  The following link is a video of my second pass, https://www.facebook.com/1800170739/videos/10216023040567731/. 

[ronnieroadster]

That's the best way to get it a nice strong tail wind good work Mike.  See you in July at Loring the extra half mile will be fun for sure.

[Mike Brown]

Looking at the wear pattern on the front tires I suspected that there was too much toe in.  I originally aligned the chassis with strings and plumb bobs and tape measures but did not have confidence in the toe in measurements.  I decided to improve on the methodology.  I used 1 inch square aluminum tube machined to bolt onto the front hubs.  By leveling the chassis and the tubes I felt that I could accurately measure the toe in directly on the tubes sticking out in front of the chassis.  To my surprise there was about a 1/4" of toe in, way to much for any application.  I corrected the toe in to 1/16".  Note that by securing the tubes vertical I could also measure the camber accurately.  Next up a few passes at the local drag strip for a "handling" run. 

[Mike Brown]

I went to the local 1/4 mile dragstrip for a test & tune session.  Normally I can make three passes in an evening.  The venue was packed, there were hundreds of cars and we were only able to make a single pass.  I did manage 138mph in the quarter.  The car handled well.  I have been adjusting the rear tire pressure down slightly on each pass.  The pressure for this pass was down to 24psi and the contact patch is still about 3/4" from the edge.  The Hoosier circuit racing rear tires do not hook up as well as the drag radials. 

[Mike Brown]

It pays to surround yourself with the brightest people you can find.  I wanted to add a fairing to the backside of the rear axle and was struggling some getting started.  A good friend that is a brilliant engineer that works in 3D along with a printer took a stab at creating a fairing for me.  He printed this section of a part that fits against the rear axle with slots for stainless steel hose clamps to secure it.  The section is thick and much stronger than I imagined.  I will provide him with a template to make a fairing for each side.  This was quite motivating to say the least. 

[Mike Brown]

I decided to add inner wheel disks to the rear wheels while in the process of streamlining the rear axle.  I found four holes in the Wilwood disk brake mounts that could be tapped 7/16-20.  I machined standoffs from brass hex material 3/4" long to put the disks in the proper location.  The brass was tapped through and short setscrews secured with Loctite make the connection to the brake mounts.  7/16-20 bolts will hold the inner disks to the standoffs. 

[Mike Brown]

I attached a photo of the mounts installed on the brake caliper mounting brackets. 

[Mike Brown]

For serviceability I made the inner disks in two pieces.  The disks will need to be removed when I bleed the brakes.  I bleed the brakes before each event.  The disks are now back off the car for a quick coat of paint.  I will then begin working on the axle streamlining after the disks are reinstalled. 

[manta22]

Mike, are those hard lines copper tubing or only copper-plated tubing? Copper tubing is not good for brake lines as it is subject to fatigue cracking from the pressure cycling of the brake fluid. Copper tubing isn't good for fuel lines either as copper is catalytic and hastens fuel chemical breakdown.

[Mike Brown]

The brake lines are NiCopp which are a combination of copper and nickel.  They are rated for use as brake lines and are much easier to bend. 

[manta22]

I've never used those brake lines before, I'll have to have a look at NiCopp. Thanks, Mike.