The Lotus Cars Community banner

1 - 11 of 11 Posts

·
Premium Member
Joined
·
2,978 Posts
Discussion Starter #1
Minnesota Autosports Club had an autocross T&T today. Autocross tomorrow.

Ben, a computer guy from my office, brought out his Evo for his first autocross experience. I think he likes it. His Evo has an aggressive E85 tune and dynos at 400 HP. Wow. When he gets suspension, wheels and tires under it, it's going to be a rocket ship. I had a bit of trouble (OK, a lot of trouble) adjusting to the turbo lag.

I fiddled about with the front swaybar adjustments on the Lotus Elise. This car is exhibiting a phenomenon I've seen on MGBs and VW Rabbits; more front swaybar equals less understeer. Yes, reducing body roll, by any means, will improve dynamic front camber and result in more front stick, not less. I had been running the bar at 4 (second-stiffest). A few events ago I pulled it back to 3 and it didn't seem to be improving all that much. Went to 2 today and the car was clearly pushing more. The manual pyrometer said that the outside edge of the front tires were heating a heck of a lot more than the rest of the tires. Took the bar right back up to 4 again and hit the skidpad. Still has some push at steady-state, but the tire is heating more evenly, and the car seems to stick better overall. I can still make the rear come around with a lift, and wheelspin (no LSD) is not an issue. Maybe I'll push it up to 5...

This is a stock 2005 with Sport Pack, no LSD. Tires are Hoosiers.
 

·
Premium Member
Joined
·
203 Posts
Are you running the blackwatch bar? I know the "suggested" setting for slicks is as stiff as possible. I've heard someone in my home region saying they need something even stiffer than the blackwatch SS bar with hoosiers and ohlins.

I've tried mine on both the 2nd and 3rd softest setting with street tires, 205 front, 235 rear, and I've had 0 push at the last few events. It's really easy to get the rear to slide out.

If I enter a turn too hot and stay on the throttle, I find the rear sliding before the front.

If I enter a turn too slow, and mash the go pedal, I find my rear sliding out as soon as power comes on.

Compared to the stock swaybar and base wheels, I CANNOT get the car to push. With the stock wheels and swaybar, the car would push an awful lot.
 

·
Premium Member
Joined
·
2,978 Posts
Discussion Starter #3
I did go ahead and crank the BWR bar up to 5 (it doesn't go to 11).

We had another T&T this last Saturday. I made a serious error with the Hoosiers. I was chalking them. Turns out chalking Hoosiers is just as bad an idea as chalking BFG R1 tires used to be. Following the chalk theory, I lowered the front pressures too low.

At 2:00, I parked the car to report for duty as Starter (not enough workers at the T&T for us to have Instructor as a work assignment). I cleaned the stones off the tires and they looked fine. At 3:00, I picked up a professional instructor for the last hour of the event. When you have the pro aboard, you can cut into line for the courses, so I got lots of runs.

In that hour, I corded both fronts, all the way around the outside. Two Hoosiers, trash.

Damn. Put the Dunlop Star Specs on for Sunday's autocross. Turns out they love the stiff front bar. In a quick sweeper, a slight lift still invokes useful oversteer. The skidpad still results in underster, but a lift turns this to oversteer.

Not real interested in dumping more tire money just now, so I bagged up the Hoosier rears and will wait for next season to decide what to do. I'll finish this season up in Super Stock on the Star Specs. SS is soft here, and I have won every event with times that don't warrant it overall. I've got the season trophy wrapped for MAC and will probably win Met Council also. Just have to hold off these Corvettes a little longer...

Is there a national street-tire class that accepts Elise cars?

Are you running the blackwatch bar? I know the "suggested" setting for slicks is as stiff as possible. I've heard someone in my home region saying they need something even stiffer than the blackwatch SS bar with hoosiers and ohlins.

I've tried mine on both the 2nd and 3rd softest setting with street tires, 205 front, 235 rear, and I've had 0 push at the last few events. It's really easy to get the rear to slide out.

If I enter a turn too hot and stay on the throttle, I find the rear sliding before the front.

If I enter a turn too slow, and mash the go pedal, I find my rear sliding out as soon as power comes on.

Compared to the stock swaybar and base wheels, I CANNOT get the car to push. With the stock wheels and swaybar, the car would push an awful lot.
 

·
Premium Member
Joined
·
601 Posts
FWIW - I'm running 225/45-15 Hankook Z214's up front and 245/45-16 rear and have my BWR bar set one hole from the stiffest. I tried it full stiff and it was better at some things (slaloms) and seemed worse at some things (too much understeer on entry into longer radius sweepers). I found that for the way I drive and on the types of local courses that one hole from full stiff works very well and is an ideal compromise.

I really like the way it handles now.

dave
 

·
Registered
Joined
·
19 Posts
Phile...since we were at the same event......and you guys are talking about "the big bar"
can you include all y'alls alignment specs....that can have some effect too.
I experienced a surprising amount of understeer with the "stock ,non lss front swaybar.I had to do some serious drop throttle to get the car to rotate....
more than I'd like,because it makes the car slow in long sweepers which we had 2 on the sunday course
my alignment is front -.8 camber and zero toe....rear -2.1 camber and 1/8 toe in.
I'm on 205 50 16 federal 595RS front and 235 45 17 rear.......don't laugh these tires are fast......
I'm looking to make some changes and adjustments to the car as its not going to be in stock...but SSP
oh yeah.....I have LSS shocks/springs on the car
 

·
Premium Member
Joined
·
2,978 Posts
Discussion Starter #7 (Edited)
I will try to remember to pull out Jeff's printout when I get home, but yours look pretty similar to what I remember.

Phile...since we were at the same event......and you guys are talking about "the big bar"
can you include all y'alls alignment specs....that can have some effect too.
I experienced a surprising amount of understeer with the "stock ,non lss front swaybar.I had to do some serious drop throttle to get the car to rotate....
more than I'd like,because it makes the car slow in long sweepers which we had 2 on the sunday course
my alignment is front -.8 camber and zero toe....rear -2.1 camber and 1/8 toe in.
I'm on 205 50 16 federal 595RS front and 235 45 17 rear.......don't laugh these tires are fast......
I'm looking to make some changes and adjustments to the car as its not going to be in stock...but SSP
oh yeah.....I have LSS shocks/springs on the car
 

·
Registered
Joined
·
126 Posts
Are you running the BWR street/track bar or the "hardcore" bar? I'm thinking about jumping into SS next year...

I'd still like to do an occasional track day...does the softest setting on the BWR bar get you back into some safer (but slower) understeering behavior?

Thanks,

Aaron


I did go ahead and crank the BWR bar up to 5 (it doesn't go to 11).

We had another T&T this last Saturday. I made a serious error with the Hoosiers. I was chalking them. Turns out chalking Hoosiers is just as bad an idea as chalking BFG R1 tires used to be. Following the chalk theory, I lowered the front pressures too low.

At 2:00, I parked the car to report for duty as Starter (not enough workers at the T&T for us to have Instructor as a work assignment). I cleaned the stones off the tires and they looked fine. At 3:00, I picked up a professional instructor for the last hour of the event. When you have the pro aboard, you can cut into line for the courses, so I got lots of runs.

In that hour, I corded both fronts, all the way around the outside. Two Hoosiers, trash.

Damn. Put the Dunlop Star Specs on for Sunday's autocross. Turns out they love the stiff front bar. In a quick sweeper, a slight lift still invokes useful oversteer. The skidpad still results in underster, but a lift turns this to oversteer.

Not real interested in dumping more tire money just now, so I bagged up the Hoosier rears and will wait for next season to decide what to do. I'll finish this season up in Super Stock on the Star Specs. SS is soft here, and I have won every event with times that don't warrant it overall. I've got the season trophy wrapped for MAC and will probably win Met Council also. Just have to hold off these Corvettes a little longer...

Is there a national street-tire class that accepts Elise cars?
 

·
Premium Member
Joined
·
203 Posts
Phile...since we were at the same event......and you guys are talking about "the big bar"
can you include all y'alls alignment specs....that can have some effect too.
I experienced a surprising amount of understeer with the "stock ,non lss front swaybar.I had to do some serious drop throttle to get the car to rotate....
more than I'd like,because it makes the car slow in long sweepers which we had 2 on the sunday course
my alignment is front -.8 camber and zero toe....rear -2.1 camber and 1/8 toe in.
I'm on 205 50 16 federal 595RS front and 235 45 17 rear.......don't laugh these tires are fast......
I'm looking to make some changes and adjustments to the car as its not going to be in stock...but SSP
oh yeah.....I have LSS shocks/springs on the car
That's interesting. I went from the 175 width front tires to a 205 front / 235 rear, I had massive understeer with the 175 tires, then went to crazy oversteer with the 205s.

The blackwatch bar on the stiffer settings brought the understeer back, but in the middle setting with that tire setup, the car is very neutral, just loose enough and very little push.

I'm running max front camber (no shims) and 3 shims in back. Not sure what that is in degrees, I'll have to measure it out one of these days. My toe settings are close to yours.
 

·
Registered
Joined
·
19 Posts
thanks Subpar(funny name)
I seem to always have more understeer in my cars/driving technique than others
My Mr2 spyder I had toed "out" in the back to make it turn and balance in sweepers
and even all the different "Miatai" I've run push abit more than I like
Guess I am the constant in these equations.
This is ALL auto X not big track /high speed stuff
 

·
Premium Member
Joined
·
2,978 Posts
Discussion Starter #11
Are you running the BWR street/track bar or the "hardcore" bar?
Mine is the Blackwatch Racing Hardcore SCCA Super Stock front sway bar.
 
1 - 11 of 11 Posts
Top