Lexus IS Forum banner

21 - 40 of 82 Posts

·
Registered
Joined
·
90 Posts
Discussion Starter #21
What are those seats i really like those!
The seats are Corbeau RRB on corbeau sliders and Planted seat brackets. They aren't FIA seats but I dont have a cage so it doesnt really matter. they are reclining which is why I ended up with them, comfortable, look great, made a huge difference for motorsports too. mine have been in for almost 2 years and they still look pretty much new amazingly. I'm a little bummed now though, they have them with colored diamond stitching at no extra charge, which look amazing, mine are just the basic cloth and vinyl ones.
 

·
Registered
Joined
·
90 Posts
Discussion Starter #22
I also can't wait to see/hear more from this build. Seems very similar to mine except that mine is only used for fun duty on the street, not daily. Looks great. Thanks for the specs on the tires, etc. I've been wanting to run something wider than my current 225 tires.

I'm actually heading to the track this coming weekend. Have recently added FRS Diff, Apexi SAFCII, and a homemade ghetto diffuser.

Here's the link to mine:
https://www.my.is/forums/f219/diamond-rough-slow-02-5spd-build-593113/
How much does the 410 gear diff change power output, or do you have a different transmission than stock? the w55 already seems to have pretty damn short gears with the 373
 

·
Registered
Joined
·
116 Posts
How much does the 410 gear diff change power output, or do you have a different transmission than stock? the w55 already seems to have pretty damn short gears with the 373
I have the stock w55. It's certainly made the car feel faster on the street. Of course it won't actually change my power output, but rather when the power is delivered. I've attached the new max speed calculations I've made for each gear. I'm heading back to VIR this weekend (although it looks like rain so I'm not sure I can compare lap times). It will be interesting to see where my shift points change. I'm well aware that any added acceleration might actually be cancelled by extra shifting. In the past on VIR full course I am in 3rd or 4th gear for the whole lap (never above 129mph).

I don't daily drive the car so I don't spend much time on the highway. That might be a deal breaker since the car will have a higher RPM while cruising, but so far it hasn't bothered me at all.

Edit: I should add that I've been thinking about and comparing our car to SpecE46 cars as well. In theory they should be somewhat close competitors (3.0 I6, RWD sedan, 5 speed). The basic recipe for those cars is 225 rwhp, gear ratios are almost identical with the 4.10 diff, 2855 lbs (that is my biggest disadvantage right now since I have full a/c, interior, sun roof), and 255 Toyo RR tires.

 

·
Registered
Joined
·
90 Posts
Discussion Starter #24
I have the stock w55. It's certainly made the car feel faster on the street. Of course it won't actually change my power output, but rather when the power is delivered. I've attached the new max speed calculations I've made for each gear. I'm heading back to VIR this weekend (although it looks like rain so I'm not sure I can compare lap times). It will be interesting to see where my shift points change. I'm well aware that any added acceleration might actually be cancelled by extra shifting. In the past on VIR full course I am in 3rd or 4th gear for the whole lap (never above 129mph).

I don't daily drive the car so I don't spend much time on the highway. That might be a deal breaker since the car will have a higher RPM while cruising, but so far it hasn't bothered me at all.

Edit: I should add that I've been thinking about and comparing our car to SpecE46 cars as well. In theory they should be somewhat close competitors (3.0 I6, RWD sedan, 5 speed). The basic recipe for those cars is 225 rwhp, gear ratios are almost identical with the 4.10 diff, 2855 lbs (that is my biggest disadvantage right now since I have full a/c, interior, sun roof), and 255 Toyo RR tires.

Doesn't look like it has shortened the gears to much, I'm bound by SCCA street touring rules and cant change rear end ratio, although I do like just being in 3 and 4 on the track and having enough torque to dig out of corners.

my car ready for the track is 3091lbs with 1/4 tank of gas, a few hundred pounds lighter than stock but still a good 300-400lbs heavier than my competition (damn 86 twins)
 

·
Registered
Joined
·
2,046 Posts
I've done Motorsport Ranch, Cresson, TX on a bunch of configurations more times than I can count, I've driven COTA in my other car, and I've done Texas motor speedway infield course a few times and a bunch of fun laps on the oval. Theyre rebuilding Eagles Canyon right now and LGmotorsports is supposed to be building another track up north of dallas.



The RT615k+s I really like on track, they suck for autox tho. on track they get to temp pretty fast, and stay consistent lap after lap, its tough to overdrive them, and good god they are cheap. $620 for a set of 255s, and they hold up to the track abuse, dont wear down super fast.



running figs bushings everywhere, Truhart Rear LCAs, Fortune auto 500s with 14k/12k swift springs, a 32mm hotchkis front sway on the stiffest setting, and a stock rear sway bar (with the hotchkis rear bar the rear end was really loose, especially under hard braking)



these cars are a ton of fun on the track, but the stock front brakes are pretty terrible, I cooked both front calipers and rotors a couple years ago, they just arent up to stopping such a heavy car.
how many track days have you put on the falkens? i just did day 7 on my federal 595 rs-rr

Sent from my Pixel 3 XL using Tapatalk
 

·
Registered
Joined
·
16 Posts
Love it! I like the idea. Although mine seems to be a dog around turns. Not sure maybe I need new coilovers or struts. Not too good at balancing out the ride.
 

·
Registered
Joined
·
90 Posts
Discussion Starter #31
Hey man, I'm getting into track days in my IS and I have a kinda weird but quick question.

What mud flap/guards are you using? I fit a set of sticky tires (re71r) for the first time on this car and as you know they kick up every piece of dirt, dust, and rocks all over the paint.
You're probably going to laugh, I made my own out of a black plastic kitchen trash can, they seem to last pretty well and you can make them as wide as you need to in order to keep the paint clean. helped mine a lot since 255 tires stick out like crazy on these cars
 

·
Registered
Joined
·
90 Posts
Discussion Starter #32
What are your alignment specs?

What other cars does the IS stack up to? Can it keep up/how does it compare to other cars?
most of my competition is Scion Frs/Twins, e36/46 non m cars and a few others. for track and auto x the FRs/twin is the car to have IMO, but I like my IS, and its fun annoying them on the occasions when I do manage to win. The IS in similar spec is harder to handle than others with the extra weight, but the torque from the old 2J is a blast
 

·
Registered
Joined
·
90 Posts
Discussion Starter #33
how many track days have you put on the falkens? i just did day 7 on my federal 595 rs-rr

Sent from my Pixel 3 XL using Tapatalk
Not sure because we've been rained out so many times this year, but others on them are getting about 5 to 8 events on them, depending on how aggressive you are on them. Ive been happy with how they feel so far, havent run them as much as I would like to though
 

·
Registered
Joined
·
90 Posts
Discussion Starter #35
Do you run an oil cooler?
Not running one yet, Ive kept a close eye on oil temps with an infrared temp gun after coming off track (oil temp gauge to be installed soon at the very least) and it's never been overly hot. I'll be keeping a close eye on it next month at COTA since that track is really tough on cars
 

·
Registered
Joined
·
2,046 Posts
Not running one yet, Ive kept a close eye on oil temps with an infrared temp gun after coming off track (oil temp gauge to be installed soon at the very least) and it's never been overly hot. I'll be keeping a close eye on it next month at COTA since that track is really tough on cars
I'm about to install a oil temp/pressure gauge while I'm still brainstorming my oil cooler setup (with remote filter mount!) but what temps are you seeing?

I'm intrigued with using the rt615k+ and I'm interested on how the 255s feel on the 8.5wide wheels you have. are the sidewalls stiff? did you lose any steering response in the name of overall grip going with such a wide tire?

what kind of alignment are you running?

damn cota looks fun! when is the event? gl hf!

Sent from my Pixel 3 XL using Tapatalk
 

·
Registered
Joined
·
90 Posts
Discussion Starter #37
I'm about to install a oil temp/pressure gauge while I'm still brainstorming my oil cooler setup (with remote filter mount!) but what temps are you seeing?

I'm intrigued with using the rt615k+ and I'm interested on how the 255s feel on the 8.5wide wheels you have. are the sidewalls stiff? did you lose any steering response in the name of overall grip going with such a wide tire?

what kind of alignment are you running?

damn cota looks fun! when is the event? gl hf!

Sent from my Pixel 3 XL using Tapatalk
Oil temps only around 200 but again, thats with external readings so I'm sure it's higher.

the car feels fantastic on those tires on track, theyre pretty stiff and very consistent at temperature, turn in and grip are excellent. havent noticed much loss of response since I run a kind of "autocross-y" alignment

alignment is about 2.5 camber in front, 2.2 in the rear, about .04 total toe out in front and about .10 total toe in for the rear.

the COTA event is a special SCCA TT event run in conjunction with race (we will get 8 sessions over 2 days I believe). really looking forward to it, expecially since the TT guys have some of the best on track etiquette of anyone I have run with.
 

·
Registered
Joined
·
2,046 Posts
Oil temps only around 200 but again, thats with external readings so I'm sure it's higher.



the car feels fantastic on those tires on track, theyre pretty stiff and very consistent at temperature, turn in and grip are excellent. havent noticed much loss of response since I run a kind of "autocross-y" alignment



alignment is about 2.5 camber in front, 2.2 in the rear, about .04 total toe out in front and about .10 total toe in for the rear.



the COTA event is a special SCCA TT event run in conjunction with race (we will get 8 sessions over 2 days I believe). really looking forward to it, expecially since the TT guys have some of the best on track etiquette of anyone I have run with.
thanks for the input. I'm still undecided which tire to mount on my 17x9... my alignment is -3.3 zero toe up front and -2.6 with -0.10 toe in the back. it would be a track dedicated set. my concern is to have it endure a 20min session and retain grip so I don't have to cool down within the session to get quality seat time. I'd have to so that with the federal RRs. I love that they've lasted 7 track says but that mid session cool down is a bit of a bummer. could be that I was running 215's tho. I'm considering upping the size to 245/40 of the same tire.

yeah TT drivers make it look easy. bc they know how each driver is going to react. not like me and the beginner group

Sent from my Pixel 3 XL using Tapatalk
 

·
Registered
Joined
·
42 Posts
Not running one yet, Ive kept a close eye on oil temps with an infrared temp gun after coming off track (oil temp gauge to be installed soon at the very least) and it's never been overly hot. I'll be keeping a close eye on it next month at COTA since that track is really tough on cars
If you're an experienced driver I'd highly recommend an oil cooler!! I just did my first event at COTA this past weekend. Running brand new 5w-30 full synthetic and my oil temps were about as high as I'd go.. I didn't push the car very hard (beginner HPDE driver) and I still broke 260f temps. Oil pressure was good (65psi @ redline) but before I push the car any harder I will need a cooler. External readings are definitely not accurate as even just normal highway driving gives me readings over 220f at like 80f ambient.

As you said, COTA is a high speed track and with summer coming in full swing soon high temps will be hard to avoid.

Good luck. Maybe I'll see you out there some time - it's a fun track!
 

·
Registered
Joined
·
2,046 Posts
beginner HPDE here! my Crosstrek saw 277F at the track but since I got the IS up and running it's be on track duty. I want to see how temps and pressure are before a cooler. hopefully it'll be June gloom so I can get some days in before it gets too hot.

Sent from my Pixel 3 XL using Tapatalk
 
21 - 40 of 82 Posts
Top