Handling issue discussion.
01-14-2016, 02:00 PM
#136
We are on the same page.
This is something I learned on motorcycles and has proven true in cars as well: I have found that the more comfortable I get with a track, and the faster I get, the earlier I apex the corners.
This is something I learned on motorcycles and has proven true in cars as well: I have found that the more comfortable I get with a track, and the faster I get, the earlier I apex the corners.
01-14-2016, 03:43 PM
#138
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Thread Starter
yes, it has raced for many many years, but its just a gutted street care with a little more power, and big tires and wheels. most everything on the car is stock components, and original 30 years old, sans the shocks and spring (which are 20 years old 
)
that has been the general consensus of the 928 guys, but no one is running the times im running except anderson /Fan in their 520hp versions on bigger slicks.
ive been watching the oil pressures for 15 years on the car, and it hasnt got to the point of concern. i think a lot of the failures have been , bad engines to start, poor driving habits and abuse. there is a sensitive #2/6 bearing issue.being in too high or two low RPM range can be a problem as can poor warm up, and shift techniques. (along with oil quality... mobil 1 turns to water at 260F, and thats where the 928 engine works at during a race on a 90F day) so, amsoil, redline, or other oils can do the job well and keep pressure up
as far as the rack, if you drive the car, you would think that the wheel movement is a little excess, but that could also be due to bump steer issues. the smaller steering wheel in the two videos helped a lot. i dont mine the desensitized wheel as long as i dong have that push and need that bus driver roller ball to steer I think getting rid of the bumpsteer with the ball joint extentions is a good place to start
stock oiling systems... not even an aftermarket cooler
as you saw in the push, there really wasnt even a diminishing rate of return. the increased angle didnt give any more grip, and only drag, so adding gas to counter act it, just allowed the car to arc around the turn and exit with a lot of noise. as i mentioned , i tried a bunch of different techniques of slower in, and faster out... but the car didnt want to turn at all, especially in the faster 80mph turns. it could have been due to the new wing and to high of angle, which as i mentioned, after that weekend, we took the angle out, added splitter, hood vents and got newer tires and the handling was night and day as shown by the second video.
) Another associated question arises when talking about new tyres and improving mechanical grip...What oiling system do you have over and above stock? From what I understand the 928 can suffer similar rod bearing issues when subjected to prolonged G forces. The 944 motors are particularly prone to long fast left handers. As you increase grip levels you are getting closer to engine failure if you don't have safeguards imho.
Overall, I think you do very well on a strict budget...but would suggest trying to put together a few dollars and take the car to a good shop or engineer. I'd bet there is a way of replacing the stock steering rack for not a ton of money too. Imagine how much difference a better rack and some suspension modifications would make? You may not even need to change the rack with geometry corrections and generally better standard of rubber.
Overall, I think you do very well on a strict budget...but would suggest trying to put together a few dollars and take the car to a good shop or engineer. I'd bet there is a way of replacing the stock steering rack for not a ton of money too. Imagine how much difference a better rack and some suspension modifications would make? You may not even need to change the rack with geometry corrections and generally better standard of rubber.
ive been watching the oil pressures for 15 years on the car, and it hasnt got to the point of concern. i think a lot of the failures have been , bad engines to start, poor driving habits and abuse. there is a sensitive #2/6 bearing issue.being in too high or two low RPM range can be a problem as can poor warm up, and shift techniques. (along with oil quality... mobil 1 turns to water at 260F, and thats where the 928 engine works at during a race on a 90F day) so, amsoil, redline, or other oils can do the job well and keep pressure up
as far as the rack, if you drive the car, you would think that the wheel movement is a little excess, but that could also be due to bump steer issues. the smaller steering wheel in the two videos helped a lot. i dont mine the desensitized wheel as long as i dong have that push and need that bus driver roller ball to steer
I think getting rid of the bumpsteer with the ball joint extentions is a good place to startstock oiling systems... not even an aftermarket cooler
I'd add that 'Slow in-Fast out' doesn't work in quite the same way for front engine / transaxle cars as it does for rear engine Porsches. But also acknowledge that there's a point where pushing harder and turning the steering wheel more results in diminishing improvements...
01-14-2016, 03:57 PM
#139
It's amazing to me the differences between "school" lines and "race" lines....i.e entry to Turn 8 (Madness) @ Mid-O. Also, if you looked at just about every turn @ WGI (before the repave) you'd see that all the rubber on the curbing (i.e where the racers go 'cos it's the fastest way) is way earlier than where the cones are placed. Yes, the cones have to be there for the novices but IMO you're better off disregarding the cones in a DE setting.
01-14-2016, 04:03 PM
#140
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Thread Starter
Perhaps equate that with 'Brake in a straightline...fast out'. That was often the mantra for you rear engine guys, no. The sentiment seems to be that Mark is overcooking the package hence getting the push/inducing the steering angle. I think the package can be improved which should allow him to continue with similar / faster corner entry speeds.
I completely agree with you, slow-in/fast out is advice that advanced DE drivers preach (not advanced drivers). It's not very fast at all, but it's also a good fall-back position for starting over when you get a little out of sorts in driving style (which happens to all of us at one point or another). I see the cycle work like this, and it doesn't really matter what car you drive:
1) learn a very late apex, slow in/fast out at DE (which isn't fast at all, but it's a good start to the sport).
2) learn to carry more speed into the corner
3) learn an earlier late apex as you carry more speed in so you don't have as much "early" rotation that is required for a typical DE very late apex
4) maximize trail braking which allows even more entry speed but also requires an earlier late apex
5) spin
When you get to the point where you are pushing the entry speed and an earlier late apex, it's really easy to apex a little too early and have to fight the front end of the car or get pinch oversteer. In my opinion, this is what has happened to Mark. He just needs to move the apex a little later (maybe too late to be fast to get back to baseline) so that he can use the back end more in the second half of the turn. Then tighten up the too late apex back to the midpoint. He's just gone too far over the line in working the front end (in my opinion).
1) learn a very late apex, slow in/fast out at DE (which isn't fast at all, but it's a good start to the sport).
2) learn to carry more speed into the corner
3) learn an earlier late apex as you carry more speed in so you don't have as much "early" rotation that is required for a typical DE very late apex
4) maximize trail braking which allows even more entry speed but also requires an earlier late apex
5) spin
When you get to the point where you are pushing the entry speed and an earlier late apex, it's really easy to apex a little too early and have to fight the front end of the car or get pinch oversteer. In my opinion, this is what has happened to Mark. He just needs to move the apex a little later (maybe too late to be fast to get back to baseline) so that he can use the back end more in the second half of the turn. Then tighten up the too late apex back to the midpoint. He's just gone too far over the line in working the front end (in my opinion).
done right it has advantages as well.this is true... more time turning, but faster and then slower in some points. the question is, what is faster.........reminds me of a test that Pobst did for SCCA magazine it was a standard hairpin, one using late apex and one not only going earlier apex, but carving around the turn from the beginning to the end. (exiting the turn , both cars went to the exit birm ) they tested for speed and times from point to point. interesting , the drive around the turn, on the inside had a faster over all time, even though he was slower going around the turn. something i always test when im racing and waiting for the car aheads tires to go away , plotting my passing strategy out...... I've been able to keep up and stay on the bumper on the exits by doing a few differnent things and paths in and out of some turns...... it also shows on other turns why that doesnt work and upon later review , you can figure out why.
01-14-2016, 04:32 PM
#141
when i instruct guys that are a little more advnanced and some newbees (and VR doesnt like this technique, but its served me very well and those ive helped) on some turns, i have folks run a little early apex. it starts the car rotation earlier. it also gives the beginners a lot more braking or slowing room should they hit the turn too fast by braking too late or not enough. late apex'ers are doomed by the mistake to run off track in to the dirt, the earl apexers have much more restate now to continue slowing until they reach a control speed that they can make the turn at ... this saves the car from getting dirty and at only a cost of missing the apex. done right it has advantages as well.
done right it has advantages as well.The late apex is far safer than the early apex and affords all the safety you think applies to the early apex.
Everything happens later with the early apex: braking, turn in, throttle application.
01-14-2016, 04:45 PM
#142
when i instruct guys that are a little more advnanced and some newbees (and VR doesnt like this technique, but its served me very well and those ive helped) on some turns, i have folks run a little early apex. it starts the car rotation earlier. it also gives the beginners a lot more braking or slowing room should they hit the turn too fast by braking too late or not enough. late apex'ers are doomed by the mistake to run off track in to the dirt, the earl apexers have much more restate now to continue slowing until they reach a control speed that they can make the turn at ... this saves the car from getting dirty and at only a cost of missing the apex. done right it has advantages as well.
done right it has advantages as well.If your newbie needs "more slowing down room", then you aren't telling them to brake properly or they are not listening. You don't remedy poor braking by apexing early.
Friends don't let friends apex early.
-Mike
Last edited by TXE36; 01-14-2016 at 05:23 PM. Reason: then not they
01-14-2016, 05:11 PM
#143
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Since all corners and cars/bikes are different there is no wrong or right way, you can use all of them. There is slower and faster so whichever way makes you faster is better
01-14-2016, 05:22 PM
#144
Not even MotoGP bikes square off corners when they are trying to go as fast as possible. The only time they do is when racing maneuvers dictate it.
All bikes and cars are momentum bikes and cars. Some just get back up to speed easier than others when momentum is sacrificed for whatever reason.
All bikes and cars are momentum bikes and cars. Some just get back up to speed easier than others when momentum is sacrificed for whatever reason.
01-14-2016, 05:28 PM
#145
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Not even MotoGP bikes square off corners when they are trying to go as fast as possible. The only time they do is when racing maneuvers dictate it.
All bikes and cars are momentum bikes and cars. Some just get back up to speed easier than others when momentum is sacrificed for whatever reason.
All bikes and cars are momentum bikes and cars. Some just get back up to speed easier than others when momentum is sacrificed for whatever reason.
However honda and yamaha or ducati in motogp do take corners different
01-14-2016, 05:37 PM
#148
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Which is what I usually tell bike guys, to listen to what bike is telling them and adjust. You don't want to force lines, you choose them based on input you get from bike.
01-14-2016, 05:50 PM
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You brought bikes in and said it is same for cars, from your experience.
I have same issues as OP with car pushing. In my case I think it is bike background, trying to keep to high speed all around corner and front is just plowing in, especially in slower corners. Think I need to find more grip in front or change style. I destroy front tires in one day.
I have same issues as OP with car pushing. In my case I think it is bike background, trying to keep to high speed all around corner and front is just plowing in, especially in slower corners. Think I need to find more grip in front or change style. I destroy front tires in one day.