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      02-25-2019, 09:45 PM   #133
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It's always something

Initial test run at Road Atlanta yesterday.

The dry sump system:

First session the track was standing water wet, which was fine with me as it meant the pace would be low and cautious and I could use the session to monitor the oil dry sump system. I wanted to bring things up to temp, but 3 laps in we were all brought in. Unfortunately someone in an Ariel Atom must have goosed the throttle climbing out of T5 and stuffed into the tire barrier, causing a full course black flag. Road Atlanta is lined with walls and when the grass is wet, if you go off you are going into a wall!

Once cleared, we got about 20 minutes left in the session. But enough to get the oil up to temp and monitor the oil pressure. The dry sump system is very different. The oil pressure is very active. I have a swept gauge and it essentially moves with the rpm’s. It’ll definitely take some time to get used to having the pressure move so much. It’s very dependent on rpm’s and temp and not g forces. Cold oil the pressure seems too high, but pressure drops as the oil gets hot. Pressure is adjustable, so something else to tweak. I expect the oil is going to run in target temps. With the cooler taped off it only got up to 225f. Ambient was only 55f and I wasn’t driving hard, but still a good sign.

At the end of the session I found I had a leaking NPT fitting for the oil pressure sender. Made a helluva mess. Got it fixed with some Teflon tape for the next session and now it’s all dry and tight. All those hose assemblies I worried about were no problem!

Handling:

Second session out the track was dry and I was looking forward to turning up the pace, but the car had a problem at full throttle. Like two coughs every few seconds. Two laps in some dipshit stuffed it into a wall and we were brought in again. When I restarted to go out once the mess was cleaned up, the car threw some codes and went into limp mode. The code reader showed throttle problems and a Lambda error. Optimistically, I cleared the codes, disconnected the battery and then hoped for the best for the next session. On the out lap, it became clear the problem was back. Throttle actuator failure. Sucks to have the day ruined by something so simple after all this work.

As for the handling, I can say that I didn’t expect to notice an improvement until pushing the car 9/10 - 10/10, but at 7/10 I could feel the car turning in better and more neutral with less push in the sweepers. A taste, but not the meal…

Parts ordered, and planning to get back out at the end of March for a redo. To be continued…
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      03-19-2019, 09:40 AM   #134
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Quote:
Originally Posted by Michael9218 View Post
The SLR controls do have their origins in the drift community. They make a race kit as well. They do increase the steering angle by moving the tie rod in toward the center of the hub/knuckle. This increases the steering. This concerned me due to the fact that the E86 already has a fast steering rack, but it feels great on track. Definitely not too fast.

.
For the SLR arms, did you order the Z4 ones or the M3 ones?
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      03-23-2019, 07:22 PM   #135
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For the SLR arms, did you order the Z4 ones or the M3 ones?
I went with stock track so I ordered the Z4 arms. If you order M3 arms, just figure in that each side will be 3/4" wider. Depending on your camber plates, this may cause too much camber. It may also cause issues for tire clearance.
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      03-25-2019, 09:00 PM   #136
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Carbon fiber quarter window panels

Finally got around to replacing the quarter window glass with carbon fiber panels. These windows provide zero visibility for me on track with my halo seat so why not replace them with carbon fiber instead of Lexan?

My first thought was to remove the glass from the window rubber, make the CF panels and glue them back onto the old rubber and reinstall the assembly to the car. But then I thought why reuse the old rubber. It's old and rubber is dense (ie, heavy). Why not mold the window assembly with carbon fiber vacuum bagged to shape.

Removing the quarter window from the car is pretty basic. I used a large break away blade to cut the adhesive around the window.



Quarter window assembly weighs 2lb 5oz.



I prepared the window for the mold with clay. To make it easier for the carbon fiber to mold into the inside corners, I used modeling clay to bevel these edges. First roughing them in and then smoothing the clay with a blade. This should also make for a more aero looking art as well.





I covered the clay with aluminum foil then waxed all for easy mold release.



I laid three layers of 3k twill fabric and vacuum bagged it. This forces the fabric into the shape. Let it sit for 12 hours at 25 inches of vacuum.



The raw piece weighed 3.4 ounces! Nice!



Trimmed to fit...



A couple coats of epoxy, sand, rub, buff, and polish and the finished result looks pretty good. Finished panel weighs 4 ounces.



I used clay to gauge how much adhesive I would need around the perimeter of the window opening. I used 3M Window Weld to mount the panel.



The finished product looks pretty good. A bit of time and effort, but very little cost compared to the roof. These quarter window panels removed over 4 pounds. while this might not seem like much, consider the roof removes 10 pounds. The large rear window removed 11 pounds. So these little panels were really a pretty good bang for the buck, IMHO. And they definitely look custom!

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      03-25-2019, 10:21 PM   #137
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Quote:
Originally Posted by Michael9218 View Post
Finally got around to replacing the quarter window glass with carbon fiber panels. These windows provide zero visibility for me on track with my halo seat so why not replace them with carbon fiber instead of Lexan?

My first thought was to remove the glass from the window rubber, make the CF panels and glue them back onto the old rubber and reinstall the assembly to the car. But then I thought why reuse the old rubber. It's old and rubber is dense (ie, heavy). Why not mold the window assembly with carbon fiber vacuum bagged to shape.

Removing the quarter window from the car is pretty basic. I used a large break away blade to cut the adhesive around the window.



Quarter window assembly weighs 2lb 5oz.



I prepared the window for the mold with clay. To make it easier for the carbon fiber to mold into the inside corners, I used modeling clay to bevel these edges. First roughing them in and then smoothing the clay with a blade. This should also make for a more aero looking art as well.





I covered the clay with aluminum foil then waxed all for easy mold release.



I laid three layers of 3k twill fabric and vacuum bagged it. This forces the fabric into the shape. Let it sit for 12 hours at 25 inches of vacuum.



The raw piece weighed 3.4 ounces! Nice!



Trimmed to fit...



A couple coats of epoxy, sand, rub, buff, and polish and the finished result looks pretty good. Finished panel weighs 4 ounces.



I used clay to gauge how much adhesive I would need around the perimeter of the window opening. I used 3M Window Weld to mount the panel.



The finished product looks pretty good. A bit of time and effort, but very little cost compared to the roof. These quarter window panels removed over 4 pounds. while this might not seem like much, consider the roof removes 10 pounds. The large rear window removed 11 pounds. So these little panels were really a pretty good bang for the buck, IMHO. And they definitely look custom!



Since I also don't need my rear quarter windows, is there some number of currencies that would persuade you to make me a set of these too? I really want to learn to work with CF but haven't done and wow those are gorgeous.

Nice work, dude. I am truly inspired by your build!
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      03-26-2019, 11:54 AM   #138
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Ooooh those quarter lights look sexy, I wish you had done them a couple of years ago, I could have placed an order!!! LOL. I put polycarb in mine, and cutting out the glass from the seal and repositioning, was a right PITA. Great solution Mike.
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      04-14-2019, 09:35 AM   #139
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Bit of an update. Decided to put some stitch welds on the diagonal strut brace tabs on the strut tower.



And made a bracket to support the backside of the power steering pump and alternator. The Achilles brackets don't have support on the backside. They claim it holds up fine, but if you have a welder and like to tinker, might as well...

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      05-01-2019, 07:08 PM   #140
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Quote:
Originally Posted by Michael9218 View Post
While tinkering around, I decided to make a wind deflector for the passenger side window. Not sure how much this will help, but it can’t hurt, eh? Looks the business…

Just browsing this build thread, quite impressive!

The passenger air deflector - probably not going to do much, air enters at the front corner and pressurizes the cockpit.

If you do a lexan rear screen, vent holes along the base of that will help exhaust cockpit pressure.

I run a 14qt Dry sump on the Gulf M3. S14 wont support negative CCP, but if the engine is turning, there is oil pressure.

Fantastic build. Love it.

Last edited by JS154; 05-01-2019 at 07:20 PM..
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      07-14-2019, 08:41 AM   #141
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Quote:
Originally Posted by Michael9218 View Post

I also realized that the bulkhead had to come out. This beast is a pain in the ass to remove. 75 spot welds and stitch welds. Many not easy to get to. But with patience and perseverance, I got the bitch out. 35 lbs! Definitely in the way of a proper cage.



Any good advice on where to start? Do you drill the welds out or just pry apart?

Cheers

Vanne

Ps, you got me thinking in the other thread.
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      07-14-2019, 06:59 PM   #142
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Quote:
Originally Posted by Vanne View Post
Any good advice on where to start? Do you drill the welds out or just pry apart?

Cheers

Vanne

Ps, you got me thinking in the other thread.
Yes...What I found worked best was a die grinder (straight and angled) with a round tipped carbide cutter and a seam buster chisel. If you don't have air, maybe find an electric equivalent.

Double Cut Carbide Rotary Burr Set:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Die grinders, straight and angled:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

You'll also need seam buster chisels. Get both:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I also bought a spot weld cutter set, but found it easier to use the die grinder.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

My process was to grind the spot or stitch weld thin and then pound in the seam buster chisel to get the spot weld to let go. Many are difficult to get to, so you'll need patience and creativity. At one point I had to cut some the bulkhead to get to some of the spot welds that are inside the box sections. In all about 75 welds.

Have fun...
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      07-17-2019, 04:53 PM   #143
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Thanks Mick, it's slated for removal in two months. Appreciate the info mate. Love how your car is coming along man, top notch. The research and development you've done is invaluable to the rest of us. Hats off.
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      07-27-2019, 10:10 AM   #144
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Nice build

Are you running this in any competitive series?
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      07-31-2019, 06:46 PM   #145
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Quote:
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Nice build

Are you running this in any competitive series?
Nope. This one is just for fun.
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      07-31-2019, 07:13 PM   #146
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Time for some updates..

It's been a pretty frustrating first half of the year. I've been plagued with gremlins unrelated to the recent modifications, so I have yet to say I have really been able to push the car and feel the affect of the motor relocation.

After the throttle actuator issue, the next track day my steering rack blew one of the little O-ring seals on the hard lines. Sent the rack to The Rack Doctor for a rebuild (mine was the first E86M rack he's seen...).

Next track day the PS pump wouldn't hold pressure.

Next track day the car started having tune issues. Threw a misfire in cylinder 6. Couldn't even finish a single lap. Decided to switch to an Epic tune. Randy to the rescue! He was great. My tune had a corrupted file. After much effort, he finally got me fixed up with an alpha N tune.

So next track weekend at Roebling (4 hour tow), first session out and the new steering rack pinion seal blows! Turns out Rich said he got a bad batch of seals. Fortunately I brought a power steering delete kit I put together and decided to throw on a tired old set of Toyo RA1's and make the best of the weekend without power steering. For those thinking this might be an option to free up a few ponies, I give you a lap around Roebling without power steering. Note the hand position in the turns. By Sunday midday, I had Popeye arms, or maybe wish I did. I had enough and went home. It also didn't help that it was like 90 degrees and very humid!

https://youtu.be/Ar2OoPaJioQ
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      07-31-2019, 08:01 PM   #147
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Transmission

So the astute listener may have noticed a gear whine in the above video. After a bit of research and deliberation, I decided to give it a go with an H pattern straight cut dogbox transmission. This particular box uses the ZF 320 case so it's a simple plug and play if you're already set up for the ZF 5 speed. Cost is about 1/3 of a Drenth sequential. Upshifts are clutchless, but downshifts still require clutch and rev match. The gearing is track specific so you essentially have 4 gears on track where with standard street gearing you really only have 3 (on tracks I run). Gear range is about the same, so tighter ratios means the motor stays in the power zone longer. First and reverse are locked out. Gears 2 - 5 are in an H pattern with 2nd up and to the left. Very cool!

So, I was just getting the hang of using this box, and digging the shifting, when the damn thing went BOOM! Very scary to watch. I was very lucky the gear oil did not ignite on the exhaust. You may notice my water temps are high. Forgot to bleed the radiator and was thinking I better pit in when, well, I got a ride back to the paddock...

https://youtu.be/FPQkn-Hlquk

The case split open like a melon. Initial suspicion is that it somehow engaged 1st and 3rd simultaneously.



As I am in discussion with the manufacturer, I will not disclose who they are.

For now, back to a standard ZF 5 speed...
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      07-31-2019, 08:18 PM   #148
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Diffuser

I've also been busy working on a diffuser idea. I got some good ideas walking around the Global Time Attack paddock at Road Atlanta a few months ago and decided to give it a go at making a large (and hopefully effective) diffuser panel.

I started by picking up a sheet of MDF and hardboard from Home Depot. I shaped this to make my mold. A bit of woodworking here helps. I covered the mold with a couple coats of epoxy to give it a hard finish that I could wax to release the carbon fiber.





I then laid up 2 sheets of 3k twill, then some 1/8" foam and topped it with some 3k plain weave. Using my cool vacuum bagging kit, I sucked the air out and let it sit for 24 hours at 25 inches mercury.



I have to say, I was blown away with how well this turned out. It's such a big piece that I expected I would screw it up somehow, but it looks awesome! The panel is 54" x 36" and weighs 5 lbs and is very rigid. The all important underside is as smooth as glass. The angle slowly slopes to 10 degrees. Now I just have to figure out the mounting for this thing!...and make a middle panel to complete the flat underside.







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      07-31-2019, 09:05 PM   #149
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Quote:
Originally Posted by Michael9218 View Post
I've also been busy working on a diffuser idea. I got some good ideas walking around the Global Time Attack paddock at Road Atlanta a few months ago and decided to give it a go at making a large (and hopefully effective) diffuser panel.

I started by picking up a sheet of MDF and hardboard from Home Depot. I shaped this to make my mold. A bit of woodworking here helps. I covered the mold with a couple coats of epoxy to give it a hard finish that I could wax to release the carbon fiber.

[IMG]https://photos.smugmug.com/BMW-Z4-Tr...IMG_1472-M.jpg[/IMG]

[IMG]https://photos.smugmug.com/BMW-Z4-Tr...IMG_1473-M.jpg[/IMG]

I then laid up 2 sheets of 3k twill, then some 1/8" foam and topped it with some 3k plain weave. Using my cool vacuum bagging kit, I sucked the air out and let it sit for 24 hours at 25 inches mercury.

[IMG]https://photos.smugmug.com/BMW-Z4-Tr...IMG_1490-M.jpg[/IMG]

I have to say, I was blown away with how well this turned out. It's such a big piece that I expected I would screw it up somehow, but it looks awesome! The panel is 54" x 36" and weighs 5 lbs and is very rigid. The all important underside is as smooth as glass. The angle slowly slopes to 10 degrees. Now I just have to figure out the mounting for this thing!...and make a middle panel to complete the flat underside.

[IMG]https://photos.smugmug.com/BMW-Z4-Tr...IMG_1492-M.jpg[/IMG]

[IMG]https://photos.smugmug.com/BMW-Z4-Tr...IMG_1493-M.jpg[/IMG]

[IMG]https://photos.smugmug.com/BMW-Z4-Tr...IMG_1494-M.jpg[/IMG]

[IMG]https://photos.smugmug.com/BMW-Z4-Tr...IMG_1495-M.jpg[/IMG]
Looks great! I noticed you didn't create the little "flaps" or "horseshoes" around the perimeter of for your vacuum bag, which is a technique that came up a lot in the various CF tutorials I've been watching. Any reason that's not necessary?
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      08-01-2019, 06:09 AM   #150
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Originally Posted by Jsinghzzzz View Post
Looks great! I noticed you didn't create the little "flaps" or "horseshoes" around the perimeter of for your vacuum bag, which is a technique that came up a lot in the various CF tutorials I've been watching. Any reason that's not necessary?
I used several pleats. Is that what you mean by flaps?
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      08-01-2019, 11:34 AM   #151
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Quote:
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Quote:
Originally Posted by Jsinghzzzz View Post
Looks great! I noticed you didn't create the little "flaps" or "horseshoes" around the perimeter of for your vacuum bag, which is a technique that came up a lot in the various CF tutorials I've been watching. Any reason that's not necessary?
I used several pleats. Is that what you mean by flaps?
Yes! I had a brain fart and couldn't think of the right word. Didn't see them in the pictures so thought you may have used a different technique.
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      11-26-2019, 09:44 AM   #152
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Flat panels and diffuser

Finished up the mid panels and installed the diffuser. Came out pretty good. Would love to get it to a wind tunnel, but seat of the pants tells me it works. Data does as well.

The mid panel will run close to the exhaust, so I had the mid section of the exhaust ceramic coated to keep the temps down. I also molded in several naca style ducts to keep air moving down the pipes and through the diff fins.





A lot of effort went into measuring the height and rake of the panels. I then made frames to suspend it under the car. I used Tinnerman fasteners for a flush mount so as not to disturb the airflow. I also made sure not to use fasteners in the all important throat of the diffuser. Smooth airflow is key!







You can see here that the airflow will be nice and smooth without interruption. The key to a diffuser is not the expansion chamber as much as the flat area in front of it and having a smooth airfoil shaped transition. This is where the air is made to speed up and create the low pressure (Bernoulli principle). This diffuser has a 10% angle.
The placement of the exhaust will likely have a bit of a turbo charged effect drawing air out the diffuser.



View that the oncoming air will have...



Four panels in all. Splitter is CF over 3/8" foam. All other panels are CF over 1/8" foam. Vacuum bagged for strength. Unbelievably light and rigid!

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      11-26-2019, 09:54 AM   #153
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      11-26-2019, 11:19 AM   #154
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