Belly Tank Build Diary

[Mike Brown]

The work has started on the new cage.  Mike bent up a new front hoop for the cage and tack welded it in place so that I could evaluate entry and exit for bail out.  With my fire suit on I could not get out of the cockpit without a lot of twisting.  Mike bent up a second hoop which is about 4" lower and 2" narrower than the original front hoop.  It could not be any smaller and still be safe to bail out of.  Mike will fabricate the balance of the cage and tack it together so that I can double check the fit before finish welding it. 

[handyguy]

SO, does the front hoop extend beyond your helmet front  in strap in position  by any amount  and 2" clearance max on each side of helmet including SFI padding ,  Newer helmets are wider than earlier ones ..  STEVE

[Mike Brown]

SO, does the front hoop extend beyond your helmet front  in strap in position  by any amount  and 2" clearance max on each side of helmet including SFI padding ,  Newer helmets are wider than earlier ones ..  STEVE

Steve,

I have Snell SA2015 helmet.  This cage is replacing the original cage on the car that was much taller and wider than it needed to be.  The original cage was designed to comply with the rules and the new one will also.  The front hoop is about 3-1/2" forward of my helmet, the rules state a minimum of 3".  The cage will be fabricated to insure 2" or less of clearance to the sides of the helmet.  This photo is of the new front hoop tack welded in place to test for ease of entry and exit.  Easy and safe bail out is very important to me.  We wanted to get the front hoop right before any other work was done on the cage.  I always have my SFI-20 fire suit on when testing for bail out as it is very thick. 

[Mike Brown]

The car is back from the fabricator.  I included a before and after photo of the cage.  The plans are to enclose the cage with a possible fairing on the backside. 

[Mike Brown]

I have started on a fairing for the new roll cage.  The current plans are to also enclose the top and sides of the roll cage.  Tomorrow it is back to the dyno for a speed density tune up.  This will include elimination of the MAF sensor which has required an air filter to smooth out the air flow in the intake system for proper operation.  With the MAF sensor gone I will eliminate the air filter and intake plumbing hanging out in the air.  I hope to pick up some additional horsepower. 

[Stainless1]

Mike, unless you put a windshield on it you are building an airbrake... especially if you do the top and sides.
Just my opinion, not necessarily that of the aero guys.... consult one 

[Mike Brown]

It is hard to see in this photo but there is a windshield.  The windshield is made entirely from Lexan (polycarbonate).  I had to add the windshield early on as there was so much lift on my helmet it was hard to see down the track. 

[Mike Brown]

I have started working again on the cockpit fairing.  I was a little apprehensive about what to do with the edge of the fairing on the front of the cage.  I have a Kirkey seat and really liked the aluminum extrusion that they use on the edge of the seats.  I sent an E-Mail to Kirkey regarding purchasing some of this extrusion and was surprised with quick response that they do sell it.  I purchase a couple of four foot lengths of this material and look forward to having a nice round edge on the fairing.  The extrusion is soft and can be easily bent around the opening and also welds well.  This was the solution that I was looking for.  I am thankful that they sell this extrusion. 

[Mike Brown]

I have started on a new air intake the engine.  Since the tune up was changed from MAF to speed density I no longer need the air filter to satisfy the MAF sensor.  I started out with a "baloney" cut on a piece of 4" tube.  I decided to machine a piece of 4-5/8" diameter plastic so that I could at least get a radius on the outside. 

[SPARKY]

are you planning on putting a scoop on the air intake?

[Mike Brown]

I am initially going to run without a scoop.  I have two different scoops.  We will evaluate all three options.  At this point with the current horsepower and weight the car spins the tires (sometimes hard) in the first three gears.  I am trying aero only improvements on my quest for 200 mph in the standing mile. 

[Dr Goggles]

You must be making a lot of power. Our car only made under 350hp with our old motor and never broke traction on the salt, it ran a best of 215.

[desotoman]

You must be making a lot of power. Our car only made under 350hp with our old motor and never broke traction on the salt, it ran a best of 215.

Good Dr. Googles,

I think the difference is the condition of your salt, as I have been told it is like glass.

Bonneville is like washboard except for maybe a little over a mile where it is smooth.

Big difference when trying to get traction. 

Just my thoughts,

Tom G.

[Mike Brown]

I am currently only racing mile events on unprepared concrete runway surfaces (ECTA Blytheville Arkansas and LTA in Loring Maine).  The last fourth pull gear on the dyno recorded 601.8 corrected rear wheel horsepower. On my last run at 192.6 mph the data logger showed a significant loss of traction in third gear at over 4,000 rpm which was about 110 mph.  I had to back off the throttle and let car re-establish traction before that I could get back on the throttle.  A lot more traction than on the salt but a much shorter distance to get up to top speed.  I am enjoying the experience and the data.  I am content to incrementally "sneak" up on the 200 mph goal. 

[Mike Brown]

Some time has past but I am back working on the lakester.  We are planning on going to Blytheville in April.  The speed density tune up is complete on the engine, the cage has modified for a lower profile and I am going to try a 2.2:1 final gear ratio verses the 2.48:1.  Still looking for 200mph in the standing mile.  I followed the Bloodhound project on Facebook.  To detect fire in the engine compartment I believe that they use linear heat sensor cable.  They had some false alarms due to the cable being pinched which caused them some head aches and subsequent removal of the engine to determine the problem.  I have always had a concern about a fire in the engine compartment of the lakester as the engine compartment cover is not easily accessible being bolted on.  I do have some experience in fire detection systems so I decided to build my own fire detection system for the lakester.  My brother is in the fire detection business and supplied me with some linear heat sensor cable.  The cable can be ran through the engine compartment.  This particular cable will send an alarm after the temperature raises to 220 degrees F for a period of time.  A photo is attached of the cable.