A&Q about Lotus
Q:
I was invited by Fox Valley Motors to attend a track day at Autobahn in Joliet, IL with a club called PDI - Performance Drivers Inc yesterday. First of all I'm very thankful to FVM for that opportunity.
I had a very hectic travel schedule the week leading up to it - got home from Las Vegas around midnight the night before - there are few things that would peel me out of bed at 5:30 am the next day... this was one of them!
For those not familar with Autobahn - a brief description - the full circuit is 3.56 miles, but it is not 1 "long" track- rather two separate tracks they can link together.. hence you do not have long straights... there are 21 turns including a couple of tight ones...
In short... it is an ideal track for a Lotus..
First - the obvious... it was BLOODY COLD out there! 35 degrees... a few snow flurries for effect... very cold for this time of year...
during the first session.. I was just trying to memorize the track.. not getting too crazy.. my instructor (Troy) was great and also knew something about turbos and this was helpful.
bear with me.. brief explanation of the day helps - because I've never been in this car when it has felt this fast before...
The aforementioned instructor - Troy -
noticed the boost gauge was reading 10-12 PSI and this may be cause for concern. we don't want to blow anything up!
The Car normally runs 6-8PSI. It was running great - so I'm thinking no crazy vaccuum leak or anything like that - but I called up Forced Fed just in case... net net: cold air + turbo = WEEEEEEE!!!! but you better make sure you have the good stuff (race gas) in the car.
next thing we did was verify the boost gauge was reading true by lumbering along in 3rd gear at 1000 RPM and briefly hitting the accelerator to the floor. it showed 1 PSI boost... this would mean the gauge is reading +1 since you are at zero in that situation. so I was in the 9-11 range..
After adding enough 104 unleaded to my 93 pump gas were are sitting around a 99 mix, I was ready to "git after it"
The FACTS: If you know Autobahn then this will be of value to you. The straights are short. there is one straight that runs directly under the timing tower - in this straight the stock Elises can get to 100-105MPH.
On the same straight, I was at red line in 4th gear which is 120MPH+ well before the first of 5 brake zones. Both instuctors I had verified this because we were laughing about it. ("Yes I will be needing some better brakes sir")
I cannot boast about my driving... I'm just not that good of a driver... but the car was amazing - it had freakish power out there in that cold air.
as where we were waving everyone by in the first session, I was getting waved by everyone to pass in the 3rd session.. including drivers I did not want to pass, because they were driving great lines and I could learn from them and I thought they were going plenty fast..
but I'm not sure how to tell the guy.. "NO I don't want to pass... I just want to camp behind ya..." the one time I passed a driver who I thought was driving a perfect speed and line, I promptly showed him how good I am by dropping two wheels off the track on the ensuing turn and narrowly averting a serious "agricultural excursion" ... that was a bit scary!
the really fun part came at the end... when I came up on the Viper... (my last car was a Viper and I loved it.. no disrespect intended at all) I caught up to him through some twisties then we got to one of the straights and he jammed on that thing...
I could not see the look on his face - but it had to be one of surprise - when he was at 120 MPH and I was still right there behind him ("What is that damned thing still doing there"?) eventually he had to let me by because the Elise is just so nimble around those tight corners...
bottom line.. I'm still checking to see if I have a loopy boost gauge - but the car felt faster than ever by "seat of the pants" and I'm thinking I like the cold midwest for now!
NNNNGIDDDY UP!!!!
A:
How is spool up coming through those tight turns in your car? Linear, or off, then suddenly on? I'm still trying to decide betwwen SC and turbo and I would like to know how the forced fed reacts on the track.
A:
Ya I too would like to know a little more about the power delivery
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I don't know that much about turbos - but both instructors commented that the power came on smoothly. I was in 4th gear the whole track for the first session and they didn't have me shift to 3rd until later in the 2nd session. Only twice on the track did I need to use 3rd.
Originally Posted by slaughtr
How is spool up coming through those tight turns in your car? Linear, or off, then suddenly on? I'm still trying to decide betwwen SC and turbo and I would like to know how the forced fed reacts on the track.
A:
I beleive 4th gear runs out at 114 actual miles per hour.
You do know Lotus speedo reads high by some 7%?
Originally Posted by vmaniola
I was at red line in 4th gear which is 120MPH+
A:
It's actually 117mph
A:
According to this table
Speed is 113MPH at 8000RPM in 4th gear. that is when red shift light comes on signifying approached redline. The spedo will show 120+ at that point due to designed inacuracy.
Sure, ECU will let you go over 8000 for a short moment but how much speed can you actually gain in that second? The car does not pull all that hard in 4th.
I guess you can reach 117 before it cuts off fuel. I don't know.
Have you actually datalogged the car to come up with that number?
Originally Posted by darkSol
It's actually 117mph
A:
When does max power peak on a NA car? I don't think it is at the red line. I just did a search - it looks like it is around 7700/7800 rpm. Is this wheer we should be shifting gears or should we wait till redline. The car hits redline so fast it might be difficult to time it much earlier.
A:
Originally Posted by catapult
When does max power peak on a NA car? I don't think it is at the red line. I just did a search - it looks like it is around 7700/7800 rpm. Is this wheer we should be shifting gears or should we wait till redline. The car hits redline so fast it might be difficult to time it much earlier.
The torque peaks at 7K, the power peaks at about 7500.
A:
this post may give you an idea of where to shift.
Originally Posted by catapult
When does max power peak on a NA car? I don't think it is at the red line. I just did a search - it looks like it is around 7700/7800 rpm. Is this wheer we should be shifting gears or should we wait till redline. The car hits redline so fast it might be difficult to time it much earlier.
A:
Originally Posted by catapult
When does max power peak on a NA car? I don't think it is at the red line. I just did a search - it looks like it is around 7700/7800 rpm. Is this wheer we should be shifting gears or should we wait till redline. The car hits redline so fast it might be difficult to time it much earlier.
To avoid falling off the high cam after the shift, you need to shift very near red-line. In first gear, it is particularly difficult to not fall off the high cam due to the gear spread between first and second...plus it all happens pretty fast.
A:
Originally Posted by slaughtr
How is spool up coming through those tight turns in your car? Linear, or off, then suddenly on? I'm still trying to decide betwwen SC and turbo and I would like to know how the forced fed reacts on the track.
Power delivery in my turbo car, which is running very well, is amazingly smooth. There's no "surge" in power that could cause a lack of control. It feels very linear as the rpm rise. The pull down low is exactly what I was looking for. By 3000 rpm it's already pulling hard and I can hear the whoosh noise of the turbo, and it just gets stronger and stronger. No surprises, no noticiable turbo lag - it's just there and adds monster torque throughout the power band. Brrrrrrrrrrrap-PSHHH-Brrrrrrrrrrrap-PSHHH-Brrrrrrrrrrrap-PSHHH! I can't imagine what 11 psi must feel like.
A:
that sounds logical. I was just reading the speedometer. I had about 100 yards of "no mans land" after the shift light went on before the braking zones start... so I'm not bothering to shift to 5th gear at that point.. but it gets to 4th gear red line very nicely
if someone does have a GPS readout of lap speeds at Autobahn I'd like to see it..
if I get set up with one... I'll post for sure.
Originally Posted by apkom
According to this table
Speed is 113MPH at 8000RPM in 4th gear. that is when red shift light comes on signifying approached redline. The spedo will show 120+ at that point due to designed inacuracy.
Sure, ECU will let you go over 8000 for a short moment but how much speed can you actually gain in that second? The car does not pull all that hard in 4th.
I guess you can reach 117 before it cuts off fuel. I don't know.
Have you actually datalogged the car to come up with that number?
A:
au contraire!
Originally Posted by apkom
The car does not pull all that hard in 4th.
A:
I might recomend this to some people especially if you track. Apogee recomended it to me and I much prefer it. I just used a peice of red electrical tape to mark right about 8600rpm. Its a much better visual reference than looking at the numbers while trying to focus on your driving.
A:
Originally Posted by Shiftlock
Power delivery in my turbo car, which is running very well, is amazingly smooth. There's no "surge" in power that could cause a lack of control. It feels very linear as the rpm rise. The pull down low is exactly what I was looking for. By 3000 rpm it's already pulling hard and I can hear the whoosh noise of the turbo, and it just gets stronger and stronger. No surprises, no noticiable turbo lag - it's just there and adds monster torque throughout the power band. Brrrrrrrrrrrap-PSHHH-Brrrrrrrrrrrap-PSHHH-Brrrrrrrrrrrap-PSHHH! I can't imagine what 11 psi must feel like.
Must...get...turbo...
A:
Originally Posted by apkom
Sure, ECU will let you go over 8000 for a short moment but how much speed can you actually gain in that second? The car does not pull all that hard in 4th.
I was one of his instructors. Getting 8500rpms in 4th gear is not an issue for this car. It pulls down the straights like a Viper. I was very impressed with this turbo's smooth power delivery and strength. The sounds (WOT to Boost to Cam to Redline) . . . Gives you the tingles and giggles .
I used to believe that S/C was THE choice for force inducting a track oriented Lotus. Not anymore. The turbo package works well and puts the Lotus clearly in the same league as the trackday-heavy-hitters (GT2/3, Z06, Viper).
A:
Originally Posted by quick2tr
I was one of his instructors. Getting 8500rpms in 4th gear is not an issue for this car. It pulls down the straights like a Viper. I was very impressed with this turbo's smooth power delivery and strength. The sounds (WOT to Boost to Cam to Redline) . . . Gives you the tingles and giggles .
I used to believe that S/C was THE choice for force inducting a track oriented Lotus. Not anymore. The turbo package works well and puts the Lotus clearly in the same league as the trackday-heavy-hitters (GT2/3, Z06, Viper).
Must...get...turbo...
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Originally Posted by ZJChaser
I might recomend this to some people especially if you track. Apogee recomended it to me and I much prefer it. I just used a peice of red electrical tape to mark right about 8600rpm. Its a much better visual reference than looking at the numbers while trying to focus on your driving.
Looking at the numbers?
You have an audible cue that the car is above 6k. You have a bright light when the car gets near red line. And, unless it's your first time on a particular track, you have an idea of what gear you're supposed to be in on each part of the track.
I don't mean to rag on someone who's offering a solution to a problem. I just want to encourage people to be aware of all the other indicators.
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Originally Posted by slaughtr
Must...get...turbo...
ha ha ha..