The Lotus Cars Community banner

1 - 20 of 25 Posts

·
Registered
Joined
·
84 Posts
Discussion Starter #1 (Edited)
Hello all,

I have been interested in the Elise/Exige ever since I got my driver's license. The opportunity presented itself to acquire a 2007 Lotus Exige S from a friend "upgrading" to an Alfa Romeo 4C. While I have participated in track days, club races, and pro races I hadn't gone to the track much in recent years for lack of a robust and challenging track car to drive. The Exige is really reinvigorating my love for the sport.

I would like to start this journal to document the progress of both car and driver toward the goal of maximizing the Exige platform on the track while retaining a streetable form. This Exige should retain its factory restraints, air conditioning, and street legality (DOT tires) while posting strong results on the track.

Thanks in advance for your feedback!

Cheers,
Sean
 

·
Registered
Joined
·
84 Posts
Discussion Starter #2 (Edited)
7/16/17 - Sonoma Raceway

After dusting off the car which had been in storage for over a year, the car went to Trackspec Autosports for fluid changes, an alignment check, and a safety inspection.

The first event for the Exige was at Sonoma. We expected the 2013 date code Toyo R888's to be the weakest point of the package, but it was actually the front brakes that gave up first. While the car was fine to drive on the street, we were surprised by the unexpected lack of friction in the brake zone into T11 hairpin on the first lap.

It turns out that the front pads were an EBC street compound emphasizing low brake dust emissions. A very kind Exige owner named Martin helped out by supplying and installing a set of PFC front brake pads, saving the day. No times were posted, but I was hooked and we finalized the deal to transfer ownership of the car.

8/13/17 - Thunderhill Raceway Park

The car had all of its creature comforts intact and an old set of tires with plenty of tread to burn off. It was decided to go on a road trip to Southern Oregon with a friend.

We stopped at Thunderhill Raceway Park on the way to get some laps since it has been over two years since I was there last. The Chrome Orange Exige was the only Lotus at the event. We parked under the canopy next to a Subaru BRZ, a Porsche Turbo S, and a pair of E46 M3's. The configuration included the cyclone ("over the top"), and we ran in the point-by group with NCRC.

The Exige ran a moderate pace of 2:13 with a passenger while short shifting between 5-6k RPM which was still fast enough to not have to give any point bys all day. It was hard to restrain from pushing harder, but we still had several hundred miles to go to reach Oregon and then needed to drive back on the same set of tires. After seeing how well the Exige handled the sweeping turns, other participants came to check out and sit in the car. Overall, it was a satisfying event and great to refresh the memory of this racetrack.
 

·
Registered
Joined
·
84 Posts
Discussion Starter #3 (Edited)
8/25/17 - Sonoma Raceway


After the first two casual days spent shaking down the car, the Exige went back to Trackspec for some initial changes. The camber was enhanced with the V2arms which were conveniently in stock. The car was aligned and corner weighted with a fresh set of Toyo R888R in stock sizes. The settings resembled Shinoo's setup for R compounds, consisting of generous negative camber at both ends with zero front toe.

The Exige was very exciting to drive at its first timed track day on 8/25. Overall, the setup was predictable and conservative, tolerant of some rough inputs in the early sessions. The result was a baseline of 1:52 in the last session of the day which was on pace with an Exige Cup 255 and an Exige S 240 with a supercharger upgrade that also attended the event.

I would like to make some changes as a result of this experience, yet there is still equally as much or more that can be improved with the driving.

The next event at Laguna Seca is only a week away. I dropped the car off at Trackspec for routine maintenance and a small alignment change. I'll also remember to drop the hot tire pressures which were in the mid-30's at Sonoma down to Trackspec's recommended pressures.
 

·
Premium Member
Joined
·
2,819 Posts
Nice write up.

Mid 30's hot is way too high. I feel that right around 28-30 hot seems to be just about right on my Elise.
R1R's, but I believe the 888's are similar.
 

·
Registered
Joined
·
979 Posts
Nice write up.

Mid 30's hot is way too high. I feel that right around 28-30 hot seems to be just about right on my Elise.
R1R's, but I believe the 888's are similar.
I posted this somewhere else the other day, but Toyo recommends 20-26 psi cold, 24-32 psi hot and operating temps of 85-95C for 800kg-1000kg cars. I run my R888 so that I'm right at 29f 30r hot, and it's a good combination. Depending on ambient, I start around 22/23 cold.
 

·
Registered
Joined
·
84 Posts
Discussion Starter #6 (Edited)
9/4/17 - Mazda Raceway Laguna Seca


I'm surprised at how much small alignment changes can affect handling. The chassis held the line much better at Laguna Seca with a small reduction of rear toe. The result is a lap time of 1:42.7 in the first session. The subsequent sessions were warmer, hence the laptimes did not improve.

Surprisingly, the PFC pads started to fade into T2 and T5 after two fast laps in a row. Brake temperatures were about 650 degrees F in the front and 400 degrees F in the rear after a cool down lap; they were likely even hotter during the session. I'm starting to think about relocating the front calipers to the rear of the car and adding a big brake kit up front.

Tire pressures were still too high at around 34 psi hot when starting at 25 psi. I'll need to drop down even further next time.
 

·
He's on fire!
Joined
·
3,194 Posts
How are you determining you need a big brake kit after measuring brake (caliper?) temps? I see many pads rated more than double the observed temperature (obviously brake fluid is also a part of this) .... conceivably you could also run ducts to the brakes to cool them a bit.
 

·
Registered
Joined
·
5,159 Posts
Very cool. I have always just run 31 f / 33 r pressure on R888 in stock sport package sizes, based on S111 recommendations.

What kind of coilovers is your car running?
 

·
Registered
Joined
·
84 Posts
Discussion Starter #9 (Edited)
How are you determining you need a big brake kit after measuring brake (caliper?) temps? I see many pads rated more than double the observed temperature (obviously brake fluid is also a part of this) .... conceivably you could also run ducts to the brakes to cool them a bit.
How much can be improved with brake cooling on the Exige platform?

I am planning to increase power soon. It would be prudent to remedy the need for additional thermal capacity. Also, I would like to shift brake bias further to the rear while still running the same pad compound at both axles. Both goals may be achieved by replacing the front brakes with a stronger package and using the original front calipers on the rear axle.

I am also open to solutions that would alter the brake bias without the need for caliper replacement. Having more braking force from the rears would take load off of the fronts.

Very cool. I have always just run 31 f / 33 r pressure on R888 in stock sport package sizes, based on S111 recommendations.

What kind of coilovers is your car running?
Thanks! I'm running the same suspension components that you described in your signature. How do you like the upgraded fuel tank and transmission cables?
 

·
Registered
Joined
·
385 Posts
Good write-up from BOE on brake upgrades, especially for those of us relatively new to Lotus.

It sounds like you want to increase the rear brake bias. Putting the front calipers in the rear and a big brake kit in the front would keep a front brake bias. As the article suggests, try putting a set of front calipers in the back, which will put more braking power in the back. Unless you going full track beast, then you should do everything.

https://www.boefab.com/blogs/tech/stopping-a-lotus-on-a-dime-every-time
 

·
Registered
Joined
·
5,159 Posts
Thanks! I'm running the same suspension components that you described in your signature. How do you like the upgraded fuel tank and transmission cables?
The tank gets the job done, I don't have any fuel starvation issues at the track even when running fairly low on fuel. The tank does make a "knocking" sound when stopped at traffic lights sometimes. This is the sound of the one way trap door opening / closing to let fuel into a baffled portion of the tank.

Shift cables are a solid improvement combined with the mounts and reinforcing the shifter base. At the track, you won't have any problem finding gears. I mostly did this mod as preventative to avoid a snapped cable at the track, as sometimes happens with the OE cable ends.
 

·
Registered
Joined
·
979 Posts
Nice laps Sean, very quick! I take it you were able to pass sound?

BOE surge tank is a great solution to prevent fuel starvation. I still wouldn't run much below a quarter tank with the stock tank though - the Lotus fuel measurement is really awful.
 

·
Registered
Joined
·
84 Posts
Discussion Starter #13 (Edited)
This past Saturday, the Exige returned to Sonoma Raceway for the SpeedSF Challenge time attack event in the "S2" class. The competition in this class includes cars such as the Porsche Cayman GT4, Chevy Corvette (C5 Z06 and C6 Z51), and highly modified Hondas and Subarus. This was the first outing with several changes to the Exige performed by Trackspec intended to help it be more competitive without compromising the ability to drive it on the street with a full interior and air conditioning.

First, the Nitron single-adjustable coilovers were replaced by BWR Penske double-adjustable units. Along with the coilovers, the stock bushings, rear toe brace, and engine mounts were replaced by Inokinetic parts. The worn Toyo Proxes R888R were swapped for Bridgestone Potenza RE-71R's on stock wheels. Finally, the vehicle received BOE's power recipe and Torque 300 tune. Many of these changes were recommended by and discussed with Lotustalk members. Thank you all for the input!

Sonoma is the most technical track in the area with few straights and several connected, "compromise" corners. The first session at this track is always eye-opening, let alone the first session with a dramatically changed setup. Pulling into the garage after the first session, I found the tires had 34-35 psi hot after starting at about 26 psi. I bled them down to 32 psi and walked to the classroom to check times.

Staring at the timesheet, I saw a 1:51.8 on the board. This time was initially disappointing because it was barely an improvement from the previous 1:52.1 set with stock power and Nitrons. The prior record holder in the S2 class set a lap of 1:49.5 earlier in the morning. The 2.3 seconds between his time and mine seemed like an eternity to make up. After contemplating for a few minutes, I decided that I shouldn't expect to immediately go set a better time just because there were better parts on the car. I had to re-learn how to drive the car to maximize the benefit of the upgrades.

In the second session, the changed balance of the car started to become more intuitive. The BWR Penske's add a significant amount of front grip and make the car more sensitive to drive. Also, the RE-71R's reach their operating temperature very quickly, but they can overheat and lose grip if driven too aggressively. Smoother steering inputs and patience with the throttle helped improve the time to 1:50.4. In the "Challenge" session, several factors aligned. The Exige caught a draft on the outlap from a Camaro ZL1 1LE and a draft to the finish line from an S2000, setting a time of 1:49.4 and winning the S2 class.

I'm excited to continue learning how to drive and adjust this new setup. The S2 class record at Sonoma is 1:48.6. I'm confident that we can eclipse that time with more practice and tuning. The Exige is an inspiring car to drive and the Trackspec team and Lotus community have made the journey very rewarding thus far. The next time attack is at Laguna Seca on June 17th.

Here is a video from the winning lap:
 

·
Registered
Joined
·
427 Posts
Nice lap, Sean.

You might want to try lower pressures with the Bridgestones. I find my car easier to drive at the limit when I'm at about 26 front and 28 rear hot and have run 25/27 with good results as well. This is on 15x8 fronts and 17x9 rears with 205 front width and 245 rear width. What wheels are you running?

It's tough to tell from the video, but it looks like your car is a bit loose in the high-speed sections. Is that the case? What are your alignment settings? In particular, what are you running for rear toe?
 

·
Registered
Joined
·
84 Posts
Discussion Starter #15
Thanks Jake. I will try using lower pressures next weekend.

The Exige is currently using stock wheels.

I agree with your observation. Right now, the front toe is set to 0 and the rear toe is set to 0.16 degrees total. What are your settings?

Nice lap, Sean.

You might want to try lower pressures with the Bridgestones. I find my car easier to drive at the limit when I'm at about 26 front and 28 rear hot and have run 25/27 with good results as well. This is on 15x8 fronts and 17x9 rears with 205 front width and 245 rear width. What wheels are you running?

It's tough to tell from the video, but it looks like your car is a bit loose in the high-speed sections. Is that the case? What are your alignment settings? In particular, what are you running for rear toe?
 

·
Registered
Joined
·
427 Posts
Thanks Jake. I will try using lower pressures next weekend.

The Exige is currently using stock wheels.

I agree with your observation. Right now, the front toe is set to 0 and the rear toe is set to 0.16 degrees total. What are your settings?
I will have to dig up my last alignment sheet from Jon, but I want to say I have about double your total rear toe. The rears are set at -2.6 degrees of camber. Up front I’m running zero toe and -2.3 degrees of camber via machined steering arms.

Shocks are custom valved BWR 8300 Penskes with 500/700 lb/in spring rates. I’m also running the BWR S/T front bar on the middle setting. This results in a bit more understeer and lets me really lean on the car with confidence in that the rear won’t misbehave.
 

·
Registered
Joined
·
399 Posts
Good work on the lap, but you are much too busy on the wheel. Your setup needs to be improved. In the video, it looks like you are spending a lot of energy trying to keep the rear of the car in line so focus on that end first.

Rear toe was mentioned and would help but once you need to go more than 3/16 inch in at the rear to calm the car you are just band aiding (your real issue is something else). Have you considered experimenting with your shock settings? Next outing get a baseline run in then take off two clicks of bump at the rear — if better try two more, if worse put back to previous setting. Then try rebound. Make sure to bleed tires until you can end a session at max of 29/31 psi front/rear for your Toyos. They should stabilize after 2-3 sessions.

If you manage to get the rear working better and you are happy with overall bite and balance, spend the rest of the day enjoying the drive and working on your lines and braking. Of course, if the front now seems unsettled then work on that. End the day by taking a few minutes to write an assessment of what worked or didn't. After a day or two back home, read your notes and make a plan for what to do before and at the next track day.

BTW — you didn’t mention ride heights. Ask around for what ride height works at tracks you run and be sure that, if you still are running stock suspension bushings, they are neutralized at your ride height settings. Definitely check your suspension bushings to make sure all are undamaged and in their proper position. Rear toe link torques!!! And anytime at the track and especially in the heat don’t forget to hydrate yourself.

Enjoy the hobby.

Bob L
 

·
Registered
Joined
·
84 Posts
Discussion Starter #18
I will have to dig up my last alignment sheet from Jon, but I want to say I have about double your total rear toe. The rears are set at -2.6 degrees of camber. Up front I’m running zero toe and -2.3 degrees of camber via machined steering arms.

Shocks are custom valved BWR 8300 Penskes with 500/700 lb/in spring rates. I’m also running the BWR S/T front bar on the middle setting. This results in a bit more understeer and lets me really lean on the car with confidence in that the rear won’t misbehave.
Jake, thanks for the reference point. I also use Penske shocks, but mine have the higher spring rates. I anticipate to add more mechanical and aero grip in the near future. The adjustable front sway bar is a good idea. I'll consider adding it after gaining more experience with the shocks.

I preferred this amount of rear toe with the Nitron shocks, but it may not necessarily be optimal with the Penske shocks. I will also likely increase the rear negative camber based on tire wear. A friend will help me read tire temperatures at the next event. We can determine the adjustments using the additional data we collect at Laguna Seca.

Good work on the lap, but you are much too busy on the wheel. Your setup needs to be improved. In the video, it looks like you are spending a lot of energy trying to keep the rear of the car in line so focus on that end first.

Rear toe was mentioned and would help but once you need to go more than 3/16 inch in at the rear to calm the car you are just band aiding (your real issue is something else). Have you considered experimenting with your shock settings? Next outing get a baseline run in then take off two clicks of bump at the rear — if better try two more, if worse put back to previous setting. Then try rebound. Make sure to bleed tires until you can end a session at max of 29/31 psi front/rear for your Toyos. They should stabilize after 2-3 sessions.

If you manage to get the rear working better and you are happy with overall bite and balance, spend the rest of the day enjoying the drive and working on your lines and braking. Of course, if the front now seems unsettled then work on that. End the day by taking a few minutes to write an assessment of what worked or didn't. After a day or two back home, read your notes and make a plan for what to do before and at the next track day.

BTW — you didn’t mention ride heights. Ask around for what ride height works at tracks you run and be sure that, if you still are running stock suspension bushings, they are neutralized at your ride height settings. Definitely check your suspension bushings to make sure all are undamaged and in their proper position. Rear toe link torques!!! And anytime at the track and especially in the heat don’t forget to hydrate yourself.

Enjoy the hobby.

Bob L
Hi Bob, thanks for the input. I agree that the Exige is currently limited by rear traction. The balance is pretty good in low speed corners, but it is a handful at higher speeds. I'm currently using BWR's suggested shock settings and agree with the idea to soften the rear settings at the next outing.

I switched from the Toyo Proxes R888R to Bridgestone Potenza RE-71R tires and will try lower pressures at the next event. The Bridgestones seemed to wear very quickly compared to the Toyos. I would like to try to get them to work properly before switching back.

Trackspec replaced the rear toe brace and suspension bushings with Inokinetic parts at the same time as installing the Penske shocks and the chassis is significantly improved.
 

·
Registered
Joined
·
399 Posts
Sean,

I’m on one of the first sets of Penske doubles from BWR, albeit recently freshened by Fred. Springs are 500/700. Ride heights are 109/114 mm but I have the Elise Parts 16 mm drop uprights so relative to suspension camber curves and roll centers the car thinks it is at 125/130 ride mm ride heights — basically the “as designed” settings.

I run mostly at Sebring and lately on Hoosier A7 tires. Very happy at the following shock settings (from full stiff): FC -11, FR -12, RC -9, RR -12. Standard S240 front bar at 1 from full stiff. Front camber -2.1*, rear -2.4*

I also have the standard S240 4-pot front calipers at the front and standard 2-pots at the rear. Car weighs 2190 with me, Cool Shirt ice chest and 3/4 full fuel.

Haven’t been out in hot weather with this setup but had only two complaints in 60-70 degree weather.
(1) I hate the Raybestos ST43 pad compound but YMMV. Carbotech compounds which I previously liked wear much too quickly at my new, much improved braking capability. Krugspeed, a Lotus race shop let me try their Wilmax pads and I liked them.
(2) with the big lateral g increase from the A7s there is too much body roll. Very tough to see out of the mirrors and at Sebring one has to watch for Porsche Cup, Ferrari Challenge, and Rolex 24 cars as well as Mike Bliss’ super Goodwood truck which show up to CHIN Sebring events in the late Fall. :surprise:
Got to consider Shinoo’s rear bar setup as trying to mitigate this with stiffer springs probably is not the way to go on bumpy tracks. Might go a couple of tenths more negative camber at both ends but need to run warmer ambients and check tire temps to decide.

Hopefully some of the above can be useful to you,
Bob L
 

·
He's on fire!
Joined
·
3,194 Posts
Sean,

I’m on one of the first sets of Penske doubles from BWR, albeit recently freshened by Fred. Springs are 500/700. Ride heights are 109/114 mm but I have the Elise Parts 16 mm drop uprights so relative to suspension camber curves and roll centers the car thinks it is at 125/130 ride mm ride heights — basically the “as designed” settings.

I run mostly at Sebring and lately on Hoosier A7 tires. Very happy at the following shock settings (from full stiff): FC -11, FR -12, RC -9, RR -12. Standard S240 front bar at 1 from full stiff. Front camber -2.1*, rear -2.4*

I also have the standard S240 4-pot front calipers at the front and standard 2-pots at the rear. Car weighs 2190 with me, Cool Shirt ice chest and 3/4 full fuel.

Haven’t been out in hot weather with this setup but had only two complaints in 60-70 degree weather.
(1) I hate the Raybestos ST43 pad compound but YMMV. Carbotech compounds which I previously liked wear much too quickly at my new, much improved braking capability. Krugspeed, a Lotus race shop let me try their Wilmax pads and I liked them.
(2) with the big lateral g increase from the A7s there is too much body roll. Very tough to see out of the mirrors and at Sebring one has to watch for Porsche Cup, Ferrari Challenge, and Rolex 24 cars as well as Mike Bliss’ super Goodwood truck which show up to CHIN Sebring events in the late Fall. :surprise:
Got to consider Shinoo’s rear bar setup as trying to mitigate this with stiffer springs probably is not the way to go on bumpy tracks. Might go a couple of tenths more negative camber at both ends but need to run warmer ambients and check tire temps to decide.

Hopefully some of the above can be useful to you,
Bob L
It will be useful to me, i'm fitting penske's right now! Did you mean "winmax" instead of wilmax? Also, have you modified brake master mc given the change in front and rear brake calipers?
 
1 - 20 of 25 Posts
Top