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heavy85

Pikes Peaks 2016

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heavy85    17

For those that dont know me I've been on here since before Jon Mortensen started his build (sorry Jon :)). Im only on here occassionaly and dont post that often but thought I would share and seek input on the Pikes Peak conversion. '72 240Z that I've had since maybe 2006 (dont recall exact dates). Ran it autox for a couple years with the 6 and tripple Mikunis then converted to LS1 power in 2008. Running mostly doing HPDE / Time Trial / Hill climb ever since. Rebuit the LS with mild cam a couple years ago where it made 364 SAE corrected WHP. Also been adding aero and lots of other development over the years. I've always been fascinated with Pikes Peak then three years ago ran my first hill climb and was hooked.

 

Reviewing the rules looks like I'll fit in the 'open' class which includes some whicked fast cars so has some higher level safety requirements. I have no dilusion of winning but just want to experience PIkes Peak then take it where it will. Here are the basics needing updated to meet safety / rule requirements:

 

- From just rollbar to full cage w/ 3/16 mounting plates (almost complete)

- Push/pull throttle cable (almost complete)

- Second extinguisher or fire system

- Misc safety wire on suspension

- Fuel cell (using '02 Camaro tank now)

- Narrower wing

 

More to come with pics.

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heavy85    17

I too look forward to seeing you finished product Jon.

 

Here is a pic before putting away for the winter

 

image_zpsa082a230.jpg

 

Some of the in process rollcage pics.

 

image_zps33d8c6e9.jpg

 

 

image_zps46a2c351.jpg

 

image_zps57a8e1ea.jpg

 

Just down to finishing the front top of the x door bars then some misc dimple plate gussets then paint.

Edited by heavy85

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RebekahsZ    106

Looks good. A couple thoughts/questions. Is PP paved or gravel? Paved I hope, cause gravel will likely tear the hell out of your car (?). Your harness bar looks a lot like mine and I wish I had "relaxed" the harness bar all the way across, including the passenger side, to allow the passenger seat to come back more and for shoulder harness adjustment space. Not an issue if no passenger seat. Do you have any trouble with your left elbow having enough clearance for steering? Your steering wheel adapter looks pretty long, and I am trying to shorten my column to give me more elbow room.

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heavy85    17

Been all paved for a couple years. Couldnt tear it up worse than the Dragon hillclimb though. That road is made of some rediculously hard rock that likes to come up.

 

We will see with elbow room but the door bars dish out. Feels good making racecar noises sitting in it in the garage. My seat is ALL the way back - like about touching the rear wheel well far back so steering wheel position is good. That is a collapsible Momo adapter but I just added a quick release. Its a super thin one and only added around and inch of length but again it feels good.

 

image_zpsc1cd7fc8.jpg

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RebekahsZ    106

Ah, I see it (the way the door bar contours) now, and I can see that the door is gutted. You must have some long legs! You have an amazing machine. The wear and tear of drag racing is what is pushing me toward paved landspeed racing. It's just a matter of limited opportunities annually to limit the amount of carnage.

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heavy85    17

Because nothing says racecar like dimple plates ...

 

image_zpsf153bbab.jpg

 

Footwell protection. Much debate here but in the end decided I wanted to keep the wheel out of my feet more than connecting to the strut towers. Plus I have other reinforcements to the tower.

 

image_zpse135119b.jpg

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tube80z    17

Overall I like your car a lot.  I do have some ideas on how you could do some of the detail work a little better.  I'm not sure you want to hear that now as you'd need to redo some of what you have done.  Specifically how you are protecting your feet.  That could be turned into a pickup point for the suspension.

 

The one area where these cars cars are weak is the floor.  you have an extra tube along the rock, which helps a lot.  I'd personally consider running a tube across the car about midpoint in the floor to connect both side.  And something similar across the back.  These can then be used to solidly mount the seat to the cage.  And if you desired you could add more triangulation to make the car stiffer.  You have connected the the entire side of the car from rear strut to lower rocker, which is really good.  A lot of builds miss this. I can't tell if you welded the rear hoop into the roof.  That's a similar mod to the dimple plates.  

 

Remember to glue in the windshield if you're doing glass.  It will add to the shell's stiffness.  Overall I think you did a really nice job.  Pikes Peak would be a great place to run, I'm totally envious.  The one thing I saw when there was you need a lot more cooling that anywhere else in the world as the air is so thin.  You may want to think about water cooling brakes if legal and/or a larger radiator and oil cooler.  

 

Looking forward to seeing this happen,

Cary

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heavy85    17

Cary - if you have any ideas on the cage or otherwise I would be glad to hear them. On the other side of the footwell bar are two tubes, one the goes sideways to the TC bucket and one diagonal up to the frame horn so while not ideal for adding stuffness at least it ties into other bracing. You have a picture of the side tube you mention? My seat is mounted to 1" square tubes across the floor and it all the way down against them height wise to get the hoop 2" above my helmet so there isnt much room that would add height. I also have a full length 1x3x0.083 subframe (would do that different and lighter if I could do over buts it's there). Yes dimple sheer plates added from the main hoop to the roof.

 

It's complete except for paint!

 

image_zps36797d00.jpg

 

image_zps8bfc9070.jpg

 

I have some time until Spring when it gets warm enough but now what color to paint it?

Edited by heavy85

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tube80z    17

So thought I'd try and upload some photos of the ideas I mentioned.  I'm not sure this will work so well but here goes.

 

This past season I saw a tire come in on an older car and the driver was lucky not to have their foot broken.

 

Slide1.jpg

 

I got to thinking about how to stiffen all this up.  I wanted all the tubes to connect so that if the wheel/tire came back at me it needed to rip apart a lot of metal, which hopefully will stop it.  This also serves to work as additional triangulation to make the car stiffer.

 

I think you have something similar to this but for adding structure to the front of the rocker to the main frame rail I was thinking along these lines.

 

Slide4.jpg

 

My car was modified so the cowl is now removable.  This allows me to add some more triangulated structure to replace what was there.  

 

I have been researching side impact and found that there's some research around the Prodrive mini that looks interesting.  I don't think you'd want to redo your door bars but they found this setup to work very well, mini-safety11b.jpg

 

And prodrive-rallye-impact-protection-2012-p

 

prodrive-rallye-impact-protection-2012-p

 

In reading some papers about side impact strength it seemed like adding a cross beam to the floor that connected the subframe connectors to the rockers and lower door bar would make a lot of sense.  There's some data in this report, http://www.dynalook.com/8th-european-ls-dyna-conference/session-1/Session1_Paper2.pdf.  If you Google body in white topology studies you can find a lot of info about strength and accident testing from the auto manufacturers.  I noticed there's definitely a trend in making the floor much stronger and connecting the sides.  

 

I did find a few interesting ideas on retrofitting from some rally sites.  One idea that seemed very interesting was to mount DOW IMPAX foam between the seat and the and the side of the car.  For my hillclimb car I'm using left and right nets along with a normal window net.  I have a basic Kirkey road race seat and I'm building my own halo wings and a basic frame to stiffen the seat.  I found some research that indicated the need for special padding to keep from getting lower back injuries.  You can read about it here, http://www.802solutions.com/crash-pad-products/.

 

I don't know if you're interested but I found some ideas on how to make the car stiffer.  A lot of them come from a really cool tech talk from BMW around the new M4.  I couldn't believe how stiff they were able to make a street car.

 

http://youtu.be/8CJ6IwVzV-A

 

I have another project for making a fun to drive streetable car and this looked like a good fit.

 

For cooling there are a couple of options to look into.  Evans cooling, which is essentially a zero pressure option or if you don't like that then retrofitting to a constant pressure system.  I saw these on a lot of the cars at Pikes Peak when I was there, http://www.crracing.com/cr-designed-products/pressurized-cooling-systems.

 

Hope this helps,

Cary

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heavy85    17

Thanks Cary - a lot to absorb there. I thought long and hard about the Prodrive door bars before going with the X. One thing is relatively speaking they are longer than a Z and go around and tie into the b pillar. I therefore assumed some of this design was specific to the geometry and constraints of the mini which dont really apply to the Z. That plus it looked really challenging to fabricate and I just went with the standard X.

 

Im also still toying with connecting the front hoop pads with the SFC by boxing it in underneath the floor. I already have a beefy transmission mount that connects the two SFC so the car is connected across the tunnel just not (yet) all the way out to the rockers except for the front rocker to TC bucket tube.

 

On the mockup pics you made I wonder if instead of tubes you just box in the underside of the frame horn. I saw that on vintage racecar build pics someone posted and have thought about it ever since. The M4 video was quite interesting. I have to think the basic unibody structure is key to getting that stiffness with the extra bracing just the last bit. Some of those braces look like they couldnt take much load but Im sure they are well engineered. This is why I wonder how to strengthen and leverage the unibody instead of just dragging the dead weight shell around attached to tube frame. I see you cut out the inner wheel arch both in front of and behind the strut - if that functional or just weight reduction?

 

I also keep looking at the front cross bar and wonder if I should somehow attach it to the firewall and tunnel but fail to come up with good idea.

 

I would love to see/read a full build thread on your car ;)

Edited by heavy85

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tube80z    17

Thanks Cary - a lot to absorb there. I thought long and hard about the Prodrive door bars before going with the X. One thing is relatively speaking they are longer than a Z and go around and tie into the b pillar. I therefore assumed some of this design was specific to the geometry and constraints of the mini which dont really apply to the Z. That plus it looked really challenging to fabricate and I just went with the standard X.

I would agree. I saw all this after I had done the Nascar style door bars on my cage. I'm pretty happy to have three tubes pressed out to the door skin and hope I never hit anything with them but in case I do there's almost 12 inches to me. I moved the seat against the tunnel and will be mounting on tubes that are connected to the cage.

 

 

Im also still toying with connecting the front hoop pads with the SFC by boxing it in underneath the floor. I already have a beefy transmission mount that connects the two SFC so the car is connected across the tunnel just not (yet) all the way out to the rockers except for the front rocker to TC bucket tube.

 

 

Perhaps the following picture of a V8 Supercar might help. There's a lot to steal from this design. They have connected the sides of the cage to the main rails and the seats float on this. This is more or less what the inside of my car is starting to look like.

 

V8%20Supercar%20Falcon.jpg

 

V8%20Supercar%20Falcon2.jpg

 

On the mockup pics you made I wonder if instead of tubes you just box in the underside of the frame horn. I saw that on vintage racecar build pics someone posted and have thought about it ever since. The M4 video was quite interesting. I have to think the basic unibody structure is key to getting that stiffness with the extra bracing just the last bit. Some of those braces look like they couldnt take much load but Im sure they are well engineered. This is why I wonder how to strengthen and leverage the unibody instead of just dragging the dead weight shell around attached to tube frame. I see you cut out the inner wheel arch both in front of and behind the strut - if that functional or just weight reduction?

The key is to always make triangles.  As long as you do that you add strength.  The Z car is missing structure that connects the front frame rails to the rockers as well as a triangulation to the strut tower from the outer rail.  This is all standard on new cars.  There are a few examples I've seen that may be of help.  These are both for older Mustangs but the front structure is very similar, http://www.sn65.com/fire%20&%20ice%20unibody%20reinforcement.htm and http://www.stangnet.com/mustang-forums/threads/torsional-rigidity-test-67-coupe.723029/.  On the Mustangs the export brace is a large contributor to torsional strength.  And it's very similar to the bracing done by BMW.  So I think that would be a good.  There's also a series about modifying a Mini that's really good called project Blinky.  They are building it like a real unibdy using folded sheet metal and spot welds.  There's a lot of ideas I got from it.  You can find it here, https://www.youtube.com/user/badobsessionmsport.

 

I also keep looking at the front cross bar and wonder if I should somehow attach it to the firewall and tunnel but fail to come up with good idea.

Hopefully the V8 supercar pictures and the export brace idea help.  On my car I have a bar that goes across the front of the unibody just behind the rocker horns and will be tied into the front frame rails.  I have just enough room to run this under my transmission as I have moved the exhaust to run down the side of the car.  This is something I just found I could add and is not shown in the first pics I posted.  I will be connecting the structure above to this.  Depending on your transmission you may or may not be able to do do this.  But I would think you could make something similar to the skid plate brace the BMW used connected your crossmember to TC buckets and perhaps a few more attachment points.  That would serve dual purpose as a skid plate and also connect all the lower suspension points to the frame rails and rockers.

 

I would love to see/read a full build thread on your car ;)

 

So would I.

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heavy85    17

Project Binky is the best thing on youtube - been following for a while but thanks for the reminder as they have a new episode. They are nuts but entertaining and skilled.

 

I noticed the BMW turned the cross member into a k-member and it looks almost exactly like mine :). Im amazed by the number of tubed behind the dash on the V8 supercar - that just seems like extra weight? Also looking at that and many other cages and there is no way you could weld 360 deg around each tube. How do people get away with this as I read rules they pretty much all say must weld all the way around the tubes. Is this only for the mandatory tubes and the optional tubes just weld as much as you can? Good to see the strut brace on the Mustang had such a big impact.

 

Due to wanting long tube headers and having cronic ground clearance issues with under car exhaust I keep thinking about side exhaust similar to what Jon did. You have any pics of your side exhaust?

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tube80z    17

Yeah, I think we all love project Blinky.  I have learned a lot from those two guys even though they act like they don't know what they are doing half the time.  It's definitely an act.  I have been doing CAD for some time though so that's nothing new.  I do think you should sue BMW for using your K-member :-)  I think adding a skid plate underneath that connects to all the points would add a good bit and it's not a bad idea to have that under the car anyway.

 

One thing to remember when you build any prepared car, or your V8 supercar, is that you don't build that cage and bracing in the car.  Those bits are built and the car is added on around it.  I used to do the former and got much smarter on my new car.  I have taken major sections off by removing the spot welds and then make whatever I want underneath and then add back only the bare minimum.  It's also given me a lot of ideas for how to make a street Z much stiffer.  But that's about the only way the welds can be done on some of those cages.  The main tubes are the required thickness for safety and all the rest are as light as needed by FEA.  There are a few videos on youtube that show the triple 8 cars being built and you can see that the newer cars have even more cage bracing.  And the most amazing rear live axle I have ever seen.

 

When you first look at these designs they seem silly.  But the stiffer you can make the car and still make weight the better.  The reason as I understand it is since the chassis is a spring it requires you to raise the rates on springs and dampers to meet the targets you want for axle stiffness.  The floppier a chassis the worse this is or you need to have a completely different method for determining the chassis setups.  When the V8 guys went to the new COTF it caused them a lot of headache because it isn't as stiff as the old car.  A number of drivers also complained about the feel of the car as the stiffer chassis is more responsive.  A lot of the rules of thumb have changed.  I have heard you need 5 times the spring stiffness for the torsion, also 10, and 20.  It's really related to the constant learning in racing.

 

I think Jon has some good shots of his exhaust.  That's the one area I forgot to document on Dave's car.  He did a 90 at the bottom of the headers and came out though/under the lower frame rail behind the TC box.  It was mostly the thin lower section but he also had to notch the main rail a little and added back in some structure.  I wasn't too worried since this was also tied to the cage.  From there the pipes came out and around the front of the rails and down the side of the car.  How close you can go depends on the mufflers you use.  There are two downsides to this mod.  The noise goes up and you need to be careful when getting in/out.  But working under the car is much easier.  Transmission and diff swaps are a lot easier and can be done on a car when it comes in off the track if needed.  

 

Hope this helps,

Cary

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heavy85    17

Looking for ideas about connecting rocker to subframe. The two round tubes are existing, one goes up to the frame horn while the more visible one connects the rocker to the rail. The bottom square tube is just sitting there but dont like it. Ideas?

 

The distraction in the foreground with the square hole is the fender.

 

image_zps9a81ac53.jpg

Edited by heavy85

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tube80z    17

A couple of options I could see.  One is to change the tube you currently have from the rocker to rail (TC connection).  Remove this and add back in so that it forms a triangle with the cross tube you have from the rocker to the rail.  Option two is to add folded sheet metal on the firewall where it bends and bring this straight down and fold back to the floor.  Connect to both frame rail and rocker.  Then add in the tubing.  The benefit to this option is you don't have to remove the existing tube from the rocker to the rail.  This will be stronger for not a lot more weight.  On the side of the car (not shown) where you have the tube going up you can fill in the area where the fill panel to the fender is.  This is covered back to the door post making another box.  That's about it for easy.  You may want to look at seeing if you can add in a crosspiece between the frame rails that would connect with this new crosspiece/torque box.  With the exhaust on the side it should be opened up just behind the flywheel area.  If you need some pictures let me know.   

 

And to finish use the BMW example.  Your K-member could connect to the TC box and back to the rocker rails.  And you can can have a skid plate that connects the crossmember/k-member, TC boxes and across the back of the engine.  The more complicated mods involve taking the rails apart and adding metal/tubing inside and working that in.

 

Hope this helps,

Cary 

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heavy85    17

Thanks Cary for all the input.

 

Now for the most complex Z gas pedal ever ... top modified and reinforced to connect to push/pull cable and the growth in the middle is the required toe strap. In the process found the plastic hingle was cracked at each of the three mounting holes so now on quest for new pedal hinge.

image_zps1f118d8e.jpg

Edited by heavy85

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RebekahsZ    106

My pedal is drive by wire, so the toe strap requirement is kinda sketch. I went to an event governed by the sanctioning body and talked with the T.I. He told me that if the pedal, harness, and throttle body actuator were all from the same car and were OEM to the engine, that the toe strap requirement was waved for DBW pedals. Not exactly on subject but related. Your car is awesome.

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heavy85    17

Thats interesting RebekahsZ. I dont really understand the purpose on a car you right foot brake on but Pikes Peak requires it. LSR I get it but otherwise it has to be so far out of the way and even then it wouldn't be intuitive to put your foot back on the gas to go digging for hook to pull it up. By then I think I would have just switched off the ignition but rules so there it is.

 

CAD (that's cereal box aided design in this case) at boxing in the footwell to connect the rocker wth the subframe. Would fill that little open triangle area in but dobt know still dont really like it.

 

image_zps21b0773e.jpg

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tube80z    17

I wouldn't do it so big.  I'd only do a 2x2 or 2x3 size area.  I don't think any larger will buy you anything extra.  You also have the door side that can be boxed from the door post to the fender liner insert.

 

Cary

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heavy85    17

Fire system install. Bottle and you can see one nozzle to the right of my shoulder. Can also see the cage is painted.

 

image_zpstkg6v3ms.jpg

 

Two more nozzles on me

 

image_zpsamoof3ky.jpg

 

Three in the engine bay

 

image_zpsvunqy4qf.jpg

 

And now the rocker to frame fail / foot protection box (still needs finished but is welded in)

 

image_zpsdcxzwdru.jpg

Edited by heavy85

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