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Discussion Starter · #81 ·
MFactory 1.5 Way LSD Installation

A couple updates ago I showed the MFactory 1.5-way LSD I had just bought for my car. I finally got around to installing it over the last week. When researching LSD options for my car there wasn’t much info out there other than “Just buy the diffsonline.com setup”. That’s great but they are crazy expensive and I prefer DIY so I can learn something along the way. MFactory has a decent reputation online so I took a chance with them. I couldn’t find any detailed reviews of the plate style LSD, only a few non BMW posts that said “works great!” I plan to use this space to show some details of the unit itself, chronicle the installation process, and give follow up reviews once I get it out on the street and track. In the future I may even do some diff tuning to see how the unit responds to preload and clutch pack adjustments.

A LSD is of no use on its own. It needs a diff carrier assembly to ride in. Before all the COVID-19 craziness I went to the local U Pull & Pay to buy a 3.46 diff carrier. I decided on the 3.46 for two reasons- 1) That’s the specified Spec E46 ratio, and 2) a slightly taller ratio will eliminate one or two shifts at my local tracks. I found a remarkably nice 2002 330xi with a clean looking diff and set about pulling it out. A diff from an AWD is good because the rear diff takes less load compared to an only RWD car. For the same mileage a xi should have less wear and tear on the gears and bearings. $75 later, plus some more for a few other parts (spare trunk, headlights, etc.), I was back home and throwing the carrier in the parts washer.





The biggest issue with an AWD diff is that the input flange doesn’t match the one on the RWD 330’s. The non-330 E46’s and the 330xi use a universal joint with a 4 bolt adapter. The 330i/ci use a 6 bolt CV joint. I found a CV input flange on eBay for just a few bucks and had it shipped to my house.



Before swapping the flanges I drained the 3.46 diff. The oil looked perfect, no metal flecks at all. I then measured the gear set backlash at .005”. It’s important to get this measurement before disassembly so you can confirm it after installing the LSD.



Next I pulled out the open diff and removed the ring gear and bearings. The bearings are pressed on and require a separator tool to remove them. Do not use a hammer to remove your bearings unless you have a new set to replace them. My bearings looked perfect so I reused them.



Before removing the input flange it is important to measure the pinion shaft bearing preload. This is done by using an in-lb dial torque wrench to measure the torque required to turn the pinion. I measured this torque at 4-5 in-lb, which is common for a broken-in setup. Removing the flange requires a thin wall 30mm socket. I took a regular one and turned down the diameter to fit in the recess for the pinion nut.





A quick hit with the impact gun and the nut popped off. I then used a puller to gently remove the flange.



The new CV flange slipped on and I torqued it down until I matched the 5 in-lb reading I measured before.



On to the LSD unit itself. It is packaged nicely and comes with extra hardware to change the spring preload.



According to the documentation it is assembled in the 1.5-way setting from the factory. I wanted to confirm this and the spring and plate stack settings before installation, so I took it all apart for inspection.



Here are some detail shots for those of you who want to see the guts up close. I was pleased with the fit, finish, and appearance of all the parts.









I confirmed the factory settings as 1.5 way, 6 springs and 4 active plates. According to their manual this should be about 55 ft-lb breakaway torque and 80% lockup. Previous experience shows that I (and most “smooth” drivers) prefer low static and high dynamic diff lock up. The factory settings should be in that ballpark. We’ll see if the E46 chassis likes this setup too.
Once I had the LSD reassembled I bolted on the ring gear and torqued it down. Then I pressed on the bearings.



I then reinstalled the differential into the housing. It barely fits due to the larger case size of the LSD. With the right combination of wiggling and turning it finally fell nicely into place. I put the outer bearing races into their original locations and then snapped in the retaining rings to their original places too.



A quick check of the backlash confirmed I kept the original .005” gear tooth clearance. I then smeared some gear marking compound on several teeth and checked the contact pattern between the ring and pinion. The results came out textbook perfect on the drive and coast sides of the gear.



The diff cover then was bolted on with a thin smear of silicone gasket maker. One the silicone dried I filled the diff with a quart of Redline 75W-110 gear oil.



Lastly I pulled out the old 3.38 open diff carrier and bolted in the new 3.46 LSD carrier. The process takes about an hour on jack stands. This is where thinking ahead on my exhaust design saved time. I was able to quickly remove the center section of the exhaust with two V-band clamps and then have all the access I needed to the CV joints and diff bolts. I didn’t get any pics of this process, sorry.

So that’s it. Not too hard of an install. You just need some special tools and a little knowledge to be successful. I have now built differentials for Ford, Jeep, Mazda, Toyota, and now BMW. They are all basically the same with minor variations to the process. The car is still up in the air while I work on the splitter so I’ll write up my break-in and street driving impressions soon.
 

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Gold

This last thread is gold to anyone who wants to install an LSD.

I have learned all your steps the hard way. It cost me one burned diff (rear cover got loose, oil went out) and two others that started whining like hell shortly after installing. I also tried installing all new bearings, but then getting the contact pattern right turned out to be difficult, when the only adjustment available is in the lock rings.

Had I seen this thread 3 years ago, I would have saved a bunch of money and a lot of time!
So.. thanks, I guess :D:thanks::bawling:
 

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Discussion Starter · #83 ·
This last thread is gold to anyone who wants to install an LSD.

I have learned all your steps the hard way. It cost me one burned diff (rear cover got loose, oil went out) and two others that started whining like hell shortly after installing. I also tried installing all new bearings, but then getting the contact pattern right turned out to be difficult, when the only adjustment available is in the lock rings.

Had I seen this thread 3 years ago, I would have saved a bunch of money and a lot of time!
So.. thanks, I guess :D:thanks::bawling:
Thanks! Always better to learn from someone else's mistakes, I say.
 

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Discussion Starter · #85 ·
Such an epic build thread dude. So much so I made an account just to say nice work !
Thanks, I appreciate it! I promise to keep the updates coming. I finished up my splitter build and should have that update posted soon. I am currently working on the wing fab and installation so look for that update soon too.
 

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Discussion Starter · #86 ·
Splitter and Air Dam Build, Part 1

I previously teased my idea for a quickly detachable and adjustable splitter. I finally got around to making it. Like other E46 designs I’ve searched, my concept uses three points to attach the splitter assembly to the chassis- The front edge of the aluminum undertray and the two frame spar/bumper mounts.

The rear mount is a simple piece of ½”x.120 U-channel that was cut to length and had three holes drilled to line up with the OEM plastic undertray screw holes. I counterbored the bolt heads so no hardware protrudes. This gives me a deep slot for the splitter’s rear edge to slide into and align laterally on the bolt heads.




For the splitter template I used a large sheet of cardboard I saved from the hood packaging. I slipped it into the U-channel and supported the front with jack stands.




I then used a 4” machinists square to transfer the vertical outline of the bumper on to the cardboard. NASA TT5 rules require a splitter that protrudes no farther than 4” from the vertical projection of the OEM bumper. I cut the template oversize so I could make the final marks and cut once the splitter was mounted and the air dam was in place. I then transferred the template to a sheet of ½” birch plywood and cut it out.






The front frame mounts are made from 1.25”x.125” aluminum structural tubing. I attached them to the outer bumper damper bolts on each frame spar. This spot is perfect because it is a straight down drop to the floor pan without getting in the way of the brake ducts, air filter, or headlights. To get my adjustment I slotted the holes ½” either side of level so I can make final splitter angle adjustments once the car is on the ground at race weight.



The front splitter mounts are made from a combination of aluminum square tubing and angles. The center piece is a 1.5”x.125” tube that slips over the 1.25” frame mount tubes. The inner and outer tubes are connected by a quick release pin that I’ll show later. I attached the center tube to the two sections of angle with an 8mm bolt. This arrangement allows some angle and position adjustment just in case it’s needed later. Final weight of each mount came out to just .65lb.






Connecting the two sides is another aluminum angle that spans the center of the splitter. This part provides a lot of strength and stiffness across the middle section. I had to notch the mounts and the stiffener so everything would continue to sit flat when bolted down.




A small notch was needed in the bottom rear edge of the bumper cover to clear the mounts. You can’t see this cut unless you’re under the car. I also had to notch the fender liner pieces too.




Here you can see how the splitter mounts are attached and put together using a quick release pin.

 

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Discussion Starter · #87 ·
Splitter & Air Dam, Part 2

I want to be able to install and remove the splitter without taking the bumper off. This way I can load the car into my trailer easier with the splitter off and then take a couple minutes at the track to pop it back on. Plus I don’t have to give up any street driving ground clearance like I would with a permanently mounted splitter. With this in mind, a while ago I removed the front fog lights and filled the openings where the lights were with a thin sheet of plastic. The fog light bezels are made to remove from the outside very easily, and they happen to be big enough for me to fit my arm into when removed. This is how I install and remove the pins that hold the splitter in place.






With the splitter mounted and level I then traced the outline of the bumper directly to the wood surface using the same 4” square.




My splitter came out to 3.25” off the ground, which should be a good height for balancing performance potential and prevent bottoming out too much.




To fill the gap between the splitter and the bumper I am making and airdam out of .070” HDPE sheet. The airdam is mounted to the splitter surface with a length of .75” x .062” aluminum angle. I cut numerous slits into the angle so it could be shaped to follow the contour of the bumper outline. It is attached with #8 wide head wood screws. The part is made as two pieces so I formed and joined them in the middle with a rivet.






With the airdam mount in place I marked the splitter at 4” projection and trimmed the splitter to final shape.




The airdam material is soft and easy to cut but also very durable and lightweight. I carefully measured, cut, and riveted the HDPE sheet to the aluminum angle forming a perfect gap filling piece that stays permanently attached to the splitter.






With the fabrication finished I took everything apart and scrubbed the aluminum pieces with a red Scotch Brite pad and painted the splitter wood with truck bed liner to seal and protect it. You can also see the finished rear mounts and braces in these pictures. I am using two pieces of 3/16” aluminum that protrude from the back of the splitter. These slot into the U-channel bolted to the undertray providing a sturdy metal to metal junction. Braces were also added to connect the front mount angle brackets to the rear mounts. These braces added a lot of strength for their half pound weight penalty. Final weight of the splitter assembly is 15.5lb. If I change to ¼” Alumalite I should be able to drop another 3-4lb.








Before I reassembled the parts I traced the splitter outline onto the rest of my 4x8 sheet so I can cut and prepare a spare to keep in the trailer.




The underside of the splitter is perfectly flat other than a 1/16” lip and button head fasteners at the back edge. I used ¼” ribbed elevator bolts to attach the wood to the aluminum mounts. These have a very wide head that sucks up into the soft wood when you tighten the nuts down.




One last thing to show is the leading edge of the splitter. It is important to put a nice radius on this edge to reduce aero pitch sensitivity and help prevent catching on things in the paddock and on the track. Plus it just looks more finished.




Lastly, here are pictures of the finished product on the car. Looking mean! I can’t wait to get out on the track and see how it feels combined with my new rear wing (currently in process). I am hoping for a 1-1.5 second improvement at High Plains Raceway due to the aero improvements.



 

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Tim I've just read through the whole thread and I loved every bit of it, keep up the great work with the car.

I also wanted to do the Fortune Auto Coilovers and the MFactory upgrades down the line, and with your reviews I'm more confident with my decision
 

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Discussion Starter · #89 ·
Tim I've just read through the whole thread and I loved every bit of it, keep up the great work with the car.

I also wanted to do the Fortune Auto Coilovers and the MFactory upgrades down the line, and with your reviews I'm more confident with my decision
Thanks! Just trying to give back to the community a little bit.
 

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Discussion Starter · #90 · (Edited)
Wing Build & Installation, Part 1

I could have hit the easy button and just bought the complete Nine Lives Racing E46 Big Wang kit. There is nothing wrong with it. I, however, wanted to improve a couple things and maybe save a few dollars as well. The main change I wanted was to make the wing more easily removable. The 9 Lives kit bolts directly to the trunk, where my design has an intermediate bracket that the wing attaches to. I simply undo four bolts at the base of the uprights and the wing assembly pops off.

My wing journey started at the local salvage yard where I found a decent trunk from a 330xi sedan. Rather than butcher my perfectly good trunk I chose to spend $40 on a donor part. I removed all the guts and de-badged the donor. Then I got to work with a grinder and cut off wheel to remove all the inner structure.





After surgery the trunk was 8.5lb lighter.



I designed my wing mounting system in CAD and then had an online laser cutting company ship the parts to me. Cost for the parts was very reasonable and everything fit perfectly. First I had to find the center of the trunk, then mark and drill for the top mounting plates.





Once the plates were bolted down I began to build an inner support structure. I used steel tubing to build braces between the upper support plates and lower doubler plates I riveted to the remaining inner structure. These braces provide a direct load path from the wing uprights to the rubber trunk supports. I can hang on the wing mounts and no bending load will be taken by the skin of the trunk.






I used temporary alignment uprights and along aluminum rod to locate and square the mounting brackets (no picture, sorry), then I welded the pieces together. You can see here how the side plates work to sandwich the wing uprights, providing a strong yet quickly removable interface.




With the trunk modifications complete I spray painted the inside black and wrapped the outside in glossy carbon vinyl. Wrapping body panels is a pain! I had to do this part in two pieces. I’m not in love with the result but it looks good enough from 5 feet away.






I painted the wing mounting brackets black and added a 1/8” firm rubber pad to the bottom. Then they were bolted on for good.




I then reassembled the lights, latch, and license plate bracket and then installed the completed trunk on the car. It fit perfectly. Final weight of the trunk lid came out to be 20lb, a 7lb savings over the original unmodified piece.



 

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Discussion Starter · #91 · (Edited)
Wing Build & Installation, Part 2
Due to early season demand and COVID-19 delays it took a couple months for my wing to arrive. It finally arrived in early May after placing the order in late February. I ordered a 69” Builder’s Wang to match the actual measured width of my car. It comes with their 10”x10” endplates but I will not be using them. I chose to design my own instead. I am also doing my own thing with the Gurney strips.

The wing comes with a nifty “welcome” surprise when you open the box.




First step in installing the airfoil on the mounts is to level the car, then set the airfoil to level with my adjusters in the desired position. I had sorted this out in CAD before ordering the components. Everything went together as planned here too. In the following images you can see the temporary alignment uprights and aluminum rod I used to keep everything straight and square.






I tacked the airfoil mounts in place on the car, then pulled it off for finish welding. Of course I ran out of Argon in the middle of this step and botched a weld because of it. I’m not the prettiest weld-maker, but they never fail!




Once the wing mounts were welded I needed to measure for the uprights. I used a level to create a reference plane at the top of the roof. I then measured from this plane to the top of my thickest Gurney while the wing was at max angle of attack. This dimension gave me the maximum height increase for my final wing uprights.




I then cut some paper endplates and fiberboard uprights to confirm my design before sending out for metal parts.






A few days later the metal parts showed up. I painted them black and then bolted everything up.




Here’s a shot of my custom 3D printed Gurney extensions. You can see how they fit into the slot at the rear edge of the airfoil and give the wing a slightly longer chord. I made three sizes- .25”, .50”, & .75”. This way I can tune downforce with both angle of attack and Gurney size. I can also vary the Gurney height across the wing span to account for downwash behind the cabin. My custom endplates are designed to work with these Gurney extensions and fit within the rules.






And finally, few close up shots of the finished product.








I’m using a couple cheap wall hangers to store the wing when it’s not bolted on the car.

 

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great work as usual Strebor, any idea on the numbers for the downforce or the drag?

where you able to at least roadtest it to get a feel?
 

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Discussion Starter · #93 ·
great work as usual Strebor, any idea on the numbers for the downforce or the drag?

where you able to at least roadtest it to get a feel?
Thanks! Nine Lives graciously publishes their data for the airfoils at numerous AoA and Gurney heights. Assuming my Gurneys and end plates are working properly then I'm assuming a 10-15% increase in drag and downforce based on similar CFD work I've found. I'll never know for sure without my own CFD test results.

Physical testing has been done. First I did a high speed highway test to confirm structural integrity. I have also done a track test- which I plan to do another write up for. I definitely can see an improvement in corner speeds and a reduction in top speed, so something is happening!
 

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Thanks! Nine Lives graciously publishes their data for the airfoils at numerous AoA and Gurney heights. Assuming my Gurneys and end plates are working properly then I'm assuming a 10-15% increase in drag and downforce based on similar CFD work I've found. I'll never know for sure without my own CFD test results.

Physical testing has been done. First I did a high speed highway test to confirm structural integrity. I have also done a track test- which I plan to do another write up for. I definitely can see an improvement in corner speeds and a reduction in top speed, so something is happening!
I take a peek at the data from 9Lives, but I wanted to hear from your own experience as you said on the second paragraph.

Will have to wait to the next write up :D
 

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Awesome build and thread! Found it and read through it all today, your fabrication and custom designs are nice and efficient.

I saw in your OP that you've had some time on an FSAE team, any highlights from that? I love hearing about other folk's time with FSAE since the stories can vary so wildly and everyone's experience is unique, and it's interesting to see where people go from there.
 

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Discussion Starter · #96 ·
Awesome build and thread! Found it and read through it all today, your fabrication and custom designs are nice and efficient.

I saw in your OP that you've had some time on an FSAE team, any highlights from that? I love hearing about other folk's time with FSAE since the stories can vary so wildly and everyone's experience is unique, and it's interesting to see where people go from there.
Thanks!

My FSAE experience is what set me up for my entire professional career, and my car/motorcycle hobbies. I was on the University of Missouri team from 1999-2003. I was the chief designer and fabricator most of those years. We had a small team and an even smaller budget but we made the most of it: 1999-4th place, 2000- 17th place, 2001-2nd place, 2002-don't want to talk about it, 2003-2nd place. I am particularly proud of the 2003 year because we won the Autocross (me driving), tied for 2nd in Design, 2nd in Endurance, and finished top 10 in every other category. A couple years after graduation I got the opportunity to buy the 2003 car and jumped on it. Here's how it looked at competition that year.



Shortly after buying it I ran a few local autocross events and won FTD handily.






A few years later I built some wings with the ultimate goal of competing at the SCCA Solo Nationals. That never happened, but the wings made the car way faster.





Here are a few videos from over the years

 

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Thanks! Nine Lives graciously publishes their data for the airfoils at numerous AoA and Gurney heights. Assuming my Gurneys and end plates are working properly then I'm assuming a 10-15% increase in drag and downforce based on similar CFD work I've found. I'll never know for sure without my own CFD test results.

Physical testing has been done. First I did a high speed highway test to confirm structural integrity. I have also done a track test- which I plan to do another write up for. I definitely can see an improvement in corner speeds and a reduction in top speed, so something is happening!
Any update on the track test for your aero?
I built a spoiler/splitter setup over last winter, but I think I might change up for a wing over this coming winter.
 

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Discussion Starter · #98 ·
Any update on the track test for your aero?
I built a spoiler/splitter setup over last winter, but I think I might change up for a wing over this coming winter.
I started to write it up but got sidetracked. Maybe I can wrap it up in a week or so.

The preview is: Top speed is down. Corner speeds are up. Lap time didn't improve- BUT- it was 100 freaking degrees out and I think that had a tremendous effect on traction, power, and downforce.
 

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Discussion Starter · #99 ·
July Track Test
Backing up a few months, I’d like to comment on the MFactory 1.5-way clutch LSD-
I now have several hundred street miles on the car and I can honestly say that if you have no desire to run your car hard on the track then do not buy this diff. Get the helical version instead. The clutch plate LSD makes itself known at every slow speed turn. It clangs and pops in tight corners while giving any throttle whatsoever. If you interrupt power while mid-turn (shifting, braking, etc) you are replied to with an even louder clunk as the diff unlocks. This is all normal from my experience with other diffs built for racing. On the plus side, I really do feel an improvement to the on-throttle behavior. The car just feels more “connected” to the road. I suspect the helical diff will give the same feeling without any of the mildly worrying noise.

To pre-track-test the wing, splitter, and hood I did a few runs on the highway up to the legal speed limit (ahem) just to make sure they were stiff and strong enough to handle the aero loads at track speeds. The hood stayed in place with no lifting or flutter. The splitter hung on. The wing looked solid in my mirrors. I could really see the endplates sucking in at highway speeds so I know the wing is doing work to bend the air. Time to head to the track.

The splitter assembly fits perfectly in the trunk.



The wing barely clears my trailer’s spare tire!



My original June test date was cancelled due to rain and fog. We rescheduled for later into July and were rewarded with a sunny and clear day. The only problem was HEAT! We don’t get many 100+ degree days in Colorado, but this was one of them. By 10am it was over 90 and I knew that my data would be a little compromised. When it’s that hot everything feels it- the driver, the tires, the engine, the downforce making air… I spent the morning sessions on my old but still good Hankook RS4’s. I had a lot of new parts on the car and needed to get some installation laps on everything to feel it out and make sure everything was working as intended.




First impressions for the car were good. The diff and aero made an immediate impression. I, on the other hand, was feeling a bit rusty. I hadn’t driven on a track since last November and I needed a couple sessions to get the limit feel back. I took the morning to get back in the groove and really feel what the car was doing. My goal was to match my previous best 2:03.7 while using the 200 treadwear Hankooks. I got nowhere close. The best I could manage with traffic and conditions was a 2:07.1. This is actually slower than my previous best on these exact tires (at a NASA race weekend). Granted the tires are a year older now, but the car has full TT5 aero, a LSD, and is 75lb lighter.

We took a lunch break and then I bolted on the Toyo RR’s. I was immediately faster, but still nowhere near the 2:03 times I ran last fall. My best for the day was a full second slower, 2:04.7. What was going on? Below is an overlay of my previous best lap (in red) vs my best lap of the test day (in gray).




I have broken things down to several factors. Some make the car slower, some make it faster. I don’t know how to quantify everything exactly, but clearly the result is slower lap times. Ultimately I think this test day was a bit of a wash as far as lap times are concerned. To really know if all of my updated parts are faster I need to compare lap times from a race weekend with similar weather.

LSD
The diff is amazing on track. I could immediately notice how much sooner and more confidently I could apply throttle. There was no inside wheel spin on throttle. Mid corner throttle corrections had a more pronounced effect. I may have picked up some corner entry understeer though. I did not notice any excessive noise on track like I hear on the street. I will do a fluid drain and refill before the next outing to see if there’s any debris. I don’t plan on making any diff preload or spring adjustments yet.

Tires
The Toyo RR’s are now on heat cycle 6. They are in their prime and I store them inside through the winter months. I think they just don’t grip as well at 98 degrees as they do at 51 degrees. I also think the pressures I was running were too high for the temperature. I need to understand their temperature/pressure sensitivity a little better.

Understeer
I was fighting chronic understeer all day. The rear end was way too stuck and the front end refused to bite with any amount of trail braking. The understeer was most pronounced in the slow to medium corners. I backed the wing off a couple notches and it felt slightly better in the medium speed corners. I think the problem is related to my setup- tire pressure, swaybars, alignment, or ride height. I am going to experiment more next time out.
You can see the understeer in the data at T1, T4, T10, & T11 (orange arrows). The red line has a nice gradual dip to minimum corner speed, indicating a nice and balanced transition into the corner. The gray line abruptly switches from braking to throttle. No matter what I did with the racing line or brake release I just couldn’t get the front tires to bite in the initial cornering phase. At one point I actually dropped a couple wheels at T1 due to understeer. The splitter survived the excursion through the dirt at least!




Aero
I am losing 6mph on the main straight due to drag. Trimming the wing out 2 degrees helped a bit without hurting grip or high speed balance. On the plus side, I was making significant gains in the high speed corners, T7 & T9 in particular (white arrows). I think I’ll see similar gains in T1, T3, and T4 when I get the handling rebalanced.

Air Density
Hot air is less dense so you make less power and downforce. How much? My calculations show a 5% reduction in Relative Density between this day and last fall. From 68.8% down to 63.7%. The yellow arrows really highlight the speed differences and I attribute a lot of this to loss of power. With my SAE corrected power of 212hp I am losing ~10hp just due to the hot conditions.

Confidence
I was rusty and didn’t feel like I was extracting everything from the car. This is most notable in braking and turn entry and not helped by the grip and conditions. I’d say my confidence was back to 95% by the end of the day though. I was also splitting my time driving a friend’s Cayman GT4 and I’m sure that had a residual mental effect (Don’t crash the $100k car…).

Track conditions
This is probably the big one. I set my best ever 2:03 flyer during a NASA race weekend, on the first session of the second day. That session is always the best for fast lap times because the track surface is clean and rubbered-in, the air is cool, and I am in great mental and physical condition. This July track day was a blistering hot Friday after the track sat dormant all week collecting dust. I really think it’s an apples to oranges situation.

Clutch
My clutch was slipping BAD in the afternoon. I had to shift very carefully and let the RPM drop fully before reapplying power between shifts. This was killing my 3-4 shift, which happens five times per lap. I got home and immediately ordered a new JBR aluminum flywheel and Sachs clutch to replace my OEM pieces with 120k miles on them. Look for a build update on that project soon.

Sorry for the long and ramble-y read. I am planning a couple more track days later this year so I hope to report back better news after more time and testing on track. I also might run the October NASA event so that will really allow me to compare lap times and data.
 

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Good read!
I have the MFactory helical, I can say it's pretty much not noticeable on the street or even track until you're turning with lots of throttle. I don't think it's quite as confidence-inspiring during oversteer conditions, but compared to an open diff it's great of course. That could also be user error; I'm definitely working on throttle commitment.

Thanks for the update! I'm planning to run with NASA for the first time at NCM in a little over a month. It will be my tenth track day, but first one with them so I have to start in HPDE 1. Thankfully it's a new course for me and quite long, so having to run in the novice group might not be terrible. :unsure:
 
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