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620 Land Speed Record


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#21 distributorguy

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Posted 29 June 2015 - 04:17 AM

Update:  the cage is almost done.  Probably 3 more hours work (a drop in the bucket considering there is nearly 150' of tubing in this small cab!)  I wish there was a way to photograph how much tubing is really in the cab, but even a fish eye camera lens wouldn't give you the feeling of how packed in it is.  The goal is to prevent death in the event of a rollover at 120+ mph, so its got to be more than a 4 point basic NHRA drag cage.  Hopefully its done tonight, painted tomorrow, then the doors can be installed.

 

At this point I can custom order the door net as required.  The tires and wheels should be here Thursday, so once the wheels are drilled and tapped for the Moon hubcaps, they can be painted, mounted, balanced, and installed.  Then the front fenders and hood can be installed.   Note the red, white, and blue drawing on the white board in the background.  That's roughly the goal for the final appearance, with some tweaks to have more blue and accent the great body lines!

 

 datinterior_zps7vvvas5f.jpg



#22 ]2eDeYe

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Posted 29 June 2015 - 05:47 AM

Hauling ass is serious business :devil: 


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#23 teagueauto21

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Posted 29 June 2015 - 05:57 AM

Looks good man, I cant wait to see this thong in action!

#24 datzenmike

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Posted 29 June 2015 - 06:10 AM

Mmm ... thongs..... in action......


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#25 distributorguy

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Posted 29 June 2015 - 06:24 AM

I'd rather see other thongs in action, but I'll put one on if you like? 

 

Here's the stance as it sits out in the sun this morning.  The back is a little high, with plans to drop in 500-1000 lbs ballast as needed to balance front/rear weight distribution.  The springs are designed to hold up to 1500 lbs in the box without negative handling.  The springs are 20% thicker and two additional leaves were added.  I figured we can remove them, but if we can't make them while at the salt.  

Hopefully the custom fornt wheels and new tires will clear the fender wells and allow at least some turning radius at this ride height?

 

dattruck_zps505jss3a.jpg



#26 teagueauto21

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Posted 29 June 2015 - 08:51 AM

I'd rather see other thongs in action, but I'll put one on if you like?


Lol, As much as id love to see that I think ill have to pass.

#27 Phixius

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Posted 29 June 2015 - 09:19 AM

is water methanol injection allowed?


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#28 distributorguy

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Posted 29 June 2015 - 09:39 AM

I don't remember if meth injection is allowed in production classes.  I think it is, but we won't have time to test it before we go.  Here's a glimpse under the back of the truck.  A discerning eye will catch a few of the changes, of which there aren't many.  Shocks will be installed as soon as I pick up the correct locking hardware.  

 

datdiff_zpskg6jrgta.jpg



#29 Farmer Joe

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Posted 29 June 2015 - 09:54 AM

what are the leaf springs from? 

 

are those metal bushings in the springs? 


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#30 distributorguy

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Posted 29 June 2015 - 10:08 AM

Custom 3" lowered  springs with 3" lowering blocks, and yes bronze bushings.   I think the springs have the same rate as the ones in my Ford Superduty.  There's about 1/4" of movement when I jump up and down in the box (200lbs).   :thumbup:   



#31 distributorguy

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Posted 30 June 2015 - 04:31 AM

It took over 3 hours to make 3 relatively simple tubes last night - the helmet halo.  One more down bar on the right side of the driver and a few small gussets and I'll be painting the interior (rattle can white.)  

I can't wait to work on brakes just for a change.  I just need to run lines and mount the master cylinder.  I can't recall if the front or rear of the master cylinder feeds the front brakes - can anyone help me here?  

 

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#32 teagueauto21

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Posted 30 June 2015 - 05:16 AM

The rear of the master cylinder closest to the firewall is what feeds the front brakes. The roll cage is looking damn good!

#33 distributorguy

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Posted 30 June 2015 - 06:11 AM

Thanks!!!



#34 distributorguy

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Posted 30 June 2015 - 07:33 AM

I just found out that our custom pistons won't be ready in time for Bonneville.  

Devastating blow, as the engine builder had assured me otherwise...  :poop:  :poop:  :poop:  :(



#35 distributorguy

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Posted 02 July 2015 - 02:21 PM

After a LOT  of phone calls, I found a set of custom domes pistons on the shelf that will work with a set of custom rods, also on the shelf, not far off of our original build design and capable of making the 250 hp we need.  Plus the cam showed up today, and short of mapping it out, it appears to be exactly what I wanted.  Monday the custom header flanges arrive ( I made extra if anyone needs them) and Tuesday I should have all the reciprocating assembly minus small end connecting rod bushings and main bearings for the custom rods.  

 

What a roller coaster this week has been!!! :frantics:



#36 orangie

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Posted 02 July 2015 - 10:33 PM

Is the cage chromoly or steel?  Is weight that important on a top end car?



#37 distributorguy

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Posted 03 July 2015 - 04:12 AM

The cage is steel.  Weight is important - but for the opposite reason than in any other racing.  To a large extent, heavier is better.  Traction isn't a guarantee via blacktop or concrete, rather its like driving on wet sand or snow.  Weight not only aids traction, but it keeps the truck acting like a flywheel and helps maintain momentum.  We have 2 miles to get up to speed and another mile to hold that speed for the average of 2 separate mile markers to attain a record.  Speeds are recorded at 1 mile, 1.25, 2, 2.25 and 3 mile marks.  The average of any two that are 1 mile apart can earn a record.  

 

Last night the team truly rallied and a large amount of loose ends were tied up.  Seat belt mounts, fire suppression system mounts, hood pins, rear window, doors assembled, and wiring strung.  We also got the rear tires and had them mounted.  Right now I'm off to have all 4 wheels road force balanced!!!



#38 datzenmike

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Posted 03 July 2015 - 05:04 AM

I guess those tires also have to handle the weight as well as the speed.


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#39 distributorguy

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Posted 03 July 2015 - 03:26 PM

The tires are rated for up to 70 psi and over 2000 lbs load each.  Not land speed tires, rather the less expensive front-runner drag tires  rated for about 225 mph.  If we get there, I'll upgrade.  :thumbup:



#40 125 CSL

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Posted 03 July 2015 - 07:06 PM

A question. Anyone every use a carbon fiber drive shaft in one of these land speed attempts?

I forgot to mention the wheel change idea - that it will gain 10 mph.  Barry actually tried 3 different tire sizes and gained something like 1/2 mph.   I'm impressed that they got over 120 in the first mile, but that will equate to 115 on the salt at best due to altitude.  We have 4:36 and  4:11  rear axles to chose from.  The lower (higher numerically) is probably better for top speed when wind resistance is a factor, but more dangerous due to driveline speeds.  I speculate with the 4:11 that our driveshaft will be rotating around 6200-6300 rpm, which will require a solid carrier bearing as opposed to the rubber diaphragm mount.  Barry runs a one-piece shaft, but that will have a tendency to "jump rope" in the center due to length, especially considering he's got a 'lil Hustler long box.  

 

You may note that I'm sharing a lot of design info, while others will not.  Our goal is to earn the record against the best possible competition, no tricks, no surprises.  This photo is only one of the obstacles we had to overcome early in the build:  a sandblasting outfit ruined the entire front clip and box. 


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