redpriest HPDE journal

[redpriest]

Originally Posted by RobE92M3

Off-throttle oversteer from carrying too much speed and power down oversteer are different. Yes, tire pressure, spring rate, rebound/compression shock settings and alignmemt settings can affect putting power down effectively on corner exit but you need to squeeze the throttle at a rate that is on the edge of tire spin occurring. It's feel. Go slower so you don't overheat the tires and for one session concentrate on one or two corners max that tire spin is occurring most. Each lap slowly increase the rate of change of the throttle until tire spin occurs. You've reached the limit so back off a tick. Now drive a few more laps maximizing corner exit acceleration. This technique with help you get a feel for just when the tires start to break traction. Now when you make changes to tire pressure, suspension settings etc, you'll easily be able to tell if it improved or decreased corner exit acceleration/grip.

I wouldn't worry about lsd stuff until you've maximized your current setup.

Hope this helps!

Thank you! This is so helpful. I will give this a whirl the next time I'm out on the track!

[bigjae1976]

Originally Posted by admranger

I think you meant A7 is suited for autocross. R7 is the road racing version. Stay off the purple crack unless you've recently won the lottery. Addictive stuff.

Yeah, got it backwards.

[redpriest]

Bimmer Challenge Round 3 at Willow Springs. This track is probably my "weakest" one right now despite being here 7 times - I went here all the time when I was starting out, then took something like a year break from it. Something about it scares me far more than a higher top speed track like Auto Club Speedway.

Probably has something to do with all the dirt/rock runoff that's wrecked quite a few cars. Needless to say I have a healthy respect for this track.

After my partial strip down at Buttonwillow, which was mainly focused on being able to transport the AE Performance roll bar I had bought from another member on m3post, I had the rest of the trunk + back seat lining stripped, along with all the speakers behind the seats.

Car came out to 3378 lbs on 3/4 tank of gas.

The track was super cold early on, which probably contributed to the crash that happened after about 2 laps into the first session. Saw a M235i spin out in front of me once the session resumed. I managed to get about 26 laps total for the day. Now that I have these BFG R1S I am loathe to "waste" their heat cycles on unproductive sessions, and the inner portion of my street tires are pretty worn, so I didn't want to risk cording them on a fun session.

Pretty sloppy day for me, I don't feel like a good groove down. Was pretty rusty from not being here in so long, but I did manage to break my previous best lap of 1:36.8 today.

[redpriest]

Bimmer Challenge Round 4 at Spring Mountain Motorsports Ranch in Pahrump, Nevada.

A key difference from my previous track day is that I finally got the Brey-Krause mounts I had ordered a month ago delivered and installed along with my new Sparco Ergo seat. This was a royal pain to mount and get in the right position, and I'm sure I ended up scuffing and stripping more thread in the seat mounting screws than I would have liked. I think I spent a good 6 or so hours messing with the seat trying to get it just right.

Last time I was at this track was almost exactly a year ago, so since then I have the benefit of:

1) Lighter weight car
2) JRZ RS Pro coilovers
3) BFG R1S tires
4) Experience.

Ran the same 3.4 mile config as last year, and dropped my time from 2:44.53 -> 2:37.58, a significant drop. It was quite a bit hotter than it was last year (80-85 deg), but I was determined to do both days. Unfortunately, I wasn't able to improve my time on the 2nd day when it was cooler in the morning, since I lined up late. Still it was good fun passing all the people and feeling like a real race hero doing it, lol.

My lap time on day 1 was good enough for P2 in B2 class.

I've put my two lap times from this year and last year together in the chart below. Blue is this year, and orange is last year's data.



I pretty much cooked it on the exit of turn 2, as you can see, and it cost me some significant time as I was able to actually shave off time compared to last year because of the lower application of power. That mistake cost me about a half second compared to my best time through that sector.



Still, it's striking to see how much better the car is with the added weight gone, even in the hotter temperatures.

[redpriest]

New PB at Laguna Seca, but kind of bittersweet. Doing some practice in preparation for Bimmer Challenge, and it's been a month, so I've been jonesing for another opportunity.

Put on some RE-71Rs I had left over from a couple track days with the M4, since I don't have R1S ready and I don't want to burn those on practice days.

Unfortunately, I was having trouble with the way the car was handling all day. I had to be extremely gentle on the throttle coming out of the corner or the car just wanted to step out. I tried to dial this out with some suspension tuning, but I wasn't able to fully prove it before I bent a rim, ironically on my PB hot lap at Turn 6:

Funny enough, I didn't notice or feel anything for the rest of the session. I did another 6 hot laps, came close to beating it with a 1:42.6. Only reason I came in was because I was low on gas. After coming back in, tooling around the paddock, filling up on gas, I witnessed the horror of this bent rim:



It was still holding pressure. I felt nervous unmounting the wheel, so I bled the air out of it while standing behind the car, lol.

I put on street tires for the rest of the day. Was able to do 1:44 laps with Kumho Ecsta PS91, the cheap tire that could, and that was fun. After the sixth session of the day (I skipped one for lunch and because of my tire woes), I came back to the paddock and started hearing this horrible knocking sound, only to see this under my car:



Looks like I sheared it straight off - that's a shame. I have to find an EC-7 wheel and somehow repair this before Bimmerfest. Ugh!

[dogbone]

Originally Posted by redpriest

Looks like I sheared it straight off - that's a shame. I have to find an EC-7 wheel and somehow repair this before Bimmerfest. Ugh!

I'm sorry to hear of your tech troubles. I see you have adjustable end links. What length are you running them? Longer, shorter or the same length as the stock end link?

(When I setup my RS Pro in 2012, I did some measuring and it seemed that JRZ put that sway bar tab in the same spot as the OEM damper, so I ended up just using the OEM end links. Been using using them ever since.)

Hope you can sort this out before the weekend.

[redpriest]

Originally Posted by dogbone

I'm sorry to hear of your tech troubles. I see you have adjustable end links. What length are you running them? Longer, shorter or the same length as the stock end link?

(When I setup my RS Pro in 2012, I did some measuring and it seemed that JRZ put that sway bar tab in the same spot as the OEM damper, so I ended up just using the OEM end links. Been using using them ever since.)

Hope you can sort this out before the weekend.

Don't know - I'm assuming same length as OEM? One of my friends said maybe had too much preload.

[dogbone]

Originally Posted by redpriest

Don't know - I'm assuming same length as OEM? One of my friends said maybe had too much preload.

Yeah, that's why I'm asking. Honestly, if you have the OEM endlinks sitting around, I would switch back to them. They have been 100% fine on my RS Pros--both with stock and aftermarket sway bars.

Are you trying to get another damper housing or are you exploring some other short term solution to get through the weekend?

[AriuSen]

Originally Posted by redpriest

Don't know - I'm assuming same length as OEM? One of my friends said maybe had too much preload.

Hope u can fix it!!
Will suck to cancel the main event of the day.

Phil vs Tito challenge

[redpriest]

Originally Posted by dogbone

Yeah, that's why I'm asking. Honestly, if you have the OEM endlinks sitting around, I would switch back to them. They have been 100% fine on my RS Pros--both with stock and aftermarket sway bars.

Are you trying to get another damper housing or are you exploring some other short term solution to get through the weekend?

I think I'm screwed as far as being able to take the E92. The place I trust here doesn't have enough time to do it by Thursday, so I'll just put on camber plates on the M4 and mount brand new R1S and hope for the best, lol.

Will be interesting to see if the stock suspension can even handle it.

[admranger]

Bummer about the wheel. That was a hard hit though. I biffed 6 the complete opposite way; went in early and went off right...hit the exit cone with the left part of the front bumper! Whoops.... gently, ever so gently added a small bit of steering to bring the car back on track (didn't want to meet the the inside wall). Worked out well.

The oversteer looked diabolical. When a car does that you can help overcome it a bit by turning in early and letting the oversteer finish the corner for you.

[roastbeef]

Of all the turns at laguna seca, 6 scares me the most. I've been off there many times in grab turismo and it's always a wall banger. Scares me in real life because I can see that being a real possibility.

[redpriest]

Been a while since I updated this thread! Lol, I've been tracking on my F82 M4 and now my (new to me) E46 M3 since my E92 has been out of commission for the past four months.

I took the opportunity to do a bunch of work in the meanwhile on the car while patiently waiting for my JRZ RS Pro suspension to be rebuilt. There was a bit of a timing SNAFU in that apparently the Dutch factory goes into half-shifts due to Summer vacation so I did not get the suspension rebuilt and shipped back to me late September.

Bummer. I literally did 10 track days in the interim, 8 in the M4, and 2 in the E46.

Here's the run down of enhancements the car has received:

* Swapped rod bearings for BE Bearings and BE ARP bolts:


* Compression test:
Cylinder 1: 180
Cylinder 2: 175
Cylinder 3: 180
Cylinder 4 170
Cylinder 5 180
Cylinder 6 170
Cylinder 7 185
Cylinder 8 170

* Fuel tank vent breather valve swap (this had been bad for at least 100k miles, I just dealt with the occasional stall at gas fill up every time)

* Bimmerworld solid aluminum subframe bushings
* Bimmerworld solid aluminum diff mounts
* AKG Poly 75D Motor mounts
* AKG Poly 95A transmission mounts
* Bad exhaust seal ring replaced

Suspension finally showed up, and it looks like they completely overhauled them. Looks brand new. They had to replace the damper bodies on the front, and it looks like there is a new design as well. I had them lengthen the hoses so I can place the canisters in a far more convenient position for me to adjust during track days.

[roastbeef]

are you going to auto club on 10/15?

[redpriest]

Originally Posted by roastbeef

are you going to auto club on 10/15?

Probably not. I'm doing ACS on the 7th (maybe), and my track budget is pretty restricted until next year. :/

[Exclusivs]

New dampers looking great! Did they do this w/o request? That'd be pretty respectable if so.

Nice "bent" wheel

[redpriest]

Since my last update, I've taken the car on three track days. Had a double day set back in October with Speed Ventures, just getting used to the car again. I brought two sets of tires - Pirelli DH scrubs in 265 size and Hankook RS4s in 275s.

The Pirelli scrubs had already been used on my E46 for 2 sessions. I got three sessions out of them before they corded, and my best lap on that day was a 1:55.8.

I was really happy with the Hankook RS4s on day 2 of that trip, I managed a 1:58.572. Great for tires that have less grip than NT01 or RE71R in my opinion.

Towards the end of that day though, I had this happen to me on track:

The battery cable issue that's been bothering my car for over two years finally bit me on the street. It had previously only bothered me occasionally - it would refuse to start the car, and no power would go to the car. After a few minutes of it throwing this fit, it would start. Now, it's a huge safety issue.

It ended up slightly flatspotting the rears of my RS4s.



I didn't think this would be a big issue, I drove home just fine on them.

However...

This past Saturday (4th of Nov) I decided to go to Speed District's track day at Buttonwillow. This was a last minute decision, since I hadn't planned on going, so I was in a rush to get tires and the battery cable TSB taken care of, which I managed to in the nick of time.

First session I decided to do RS4s, and ended up spinning a couple times at Bus Stop. I had less grip than I had before, and I figured out why:



Serious chunking, LOL. Both rears are kind of like this, this is the right side (I spun out at bus stop, left handed turn).

I hadn't planned on putting on the new Pirellis I had mounted at Buttonwillow, but I had no choice. Glad I did though! I improved on my previous PB of 1:55 even to 1:54.598.

There's definitely more room in the tires, had a couple of mistakes in this lap that cost me - braked too deep into offramp (Buttonhook) which compromised my exit towards the long straight before Cotton Corners. Also coming down out of Phil Hill, had an oversteer moment which cost me more time as well.

I have a best rolling lap just barely < 1:53 - so there's a new target for me to hit, as long as I don't screw up some of these turns! Too bad the start-stop finish line isn't at Phil Hill, lol.

[roastbeef]

i can't remember if you talked about it yet, but how do you like the solid sub/diff bushings? they made a big difference for me for a seemingly small upgrade.

[redpriest]

Originally Posted by roastbeef

i can't remember if you talked about it yet, but how do you like the solid sub/diff bushings? they made a big difference for me for a seemingly small upgrade.

I wish I could say I felt a difference, but it had been too long since I tracked the E92 since it was down. I'd spent a considerable number of track days in the F82 and E46 which polluted my memory of the car.

I will say that the car feels fantastic handling wise since I got it back, The fact that I can hit 1:53s in this car (provided I don't screw it up) at Buttonwillow with no aero is nice.

[///Mobbin]

Originally Posted by redpriest

* Bimmerworld solid aluminum subframe bushings
* Bimmerworld solid aluminum diff mounts
* AKG Poly 75D Motor mounts
* AKG Poly 95A transmission mounts

After a brilliant weekend at COTA I'm eager to select my next set of mods and have been thinking about what you've listed above. Since I have DCT I may do Powerflex purple or black diff mounts instead of solid (to reduce diff whine as it's elevated on DCT) but am considering everything else you've listed, curious to hear your thoughts on the above after tracking?

Since I would be dropping the rear subframe, I am also thinking to go ahead and do Hotchkis front/rear sway set as well.

Current mods:
Dinan intake/exhaust/pulley stage II tune
Full GTS DCT tune
Dinan (BMW Motorsport) 3.45 rear diff gearset
MCS 2WNR 600/900
Vorshlag camber plates
RE street front tension arm bushings
Stoptech ST40 front BBK
Cobra Imola Pro-fit GT seats
Schroth Enduro harnesses
Brey Krause harness bar and seat mounts

Current Tire Selection: Cup 2's, RE-71r, NT01
Current Brake Pad Selection: Pagid black/yellow

Rod bearings swapped last December

Anything else I should consider?

[macdude357]

Originally Posted by redpriest

There's definitely more room in the tires, had a couple of mistakes in this lap that cost me - braked too deep into offramp (Buttonhook) which compromised my exit towards the long straight before Cotton Corners. Also coming down out of Phil Hill, had an oversteer moment which cost me more time as well.

I have a best rolling lap just barely < 1:53 - so there's a new target for me to hit, as long as I don't screw up some of these turns! Too bad the start-stop finish line isn't at Phil Hill, lol.

Wow, you can really here the diff whine in that video.

[admranger]

Originally Posted by ///Mobbin

After a brilliant weekend at COTA I'm eager to select my next set of mods and have been thinking about what you've listed above. Since I have DCT I may do Powerflex purple or black diff mounts instead of solid (to reduce diff whine as it's elevated on DCT) but am considering everything else you've listed, curious to hear your thoughts on the above after tracking?

Since I would be dropping the rear subframe, I am also thinking to go ahead and do Hotchkis front/rear sway set as well.

Current mods:
Dinan intake/exhaust/pulley stage II tune
Full GTS DCT tune
Dinan (BMW Motorsport) 3.45 rear diff gearset
MCS 2WNR 600/900
Vorshlag camber plates
RE street front tension arm bushings
Stoptech ST40 front BBK
Cobra Imola Pro-fit GT seats
Schroth Enduro harnesses
Brey Krause harness bar and seat mounts

Current Tire Selection: Cup 2's, RE-71r, NT01
Current Brake Pad Selection: Pagid black/yellow

Rod bearings swapped last December

Anything else I should consider?

What investments are you making in upgrading the driver? Continuous learning! Do you have data acquisition?