2013FSport

iTrader: (2)

Red, sorry to thread jack....
This is just me but the ad alone scared me away. **** if you really have that much torque at launch maybe the 3.70 gear will work but I'd imagine it will hurt more than it will help.

@DickH That said the LSD could really help. The fleebay ad is scary, no way I'd go there. Based on everything you've addressed I'd say you could set up a diff. The complication is swapping pinions from case to case.
We can take that up elsewhere but it sounds like grinding a case and setting backlash are in your means.
I have access to a lathe so it would be pretty easy to make a pinion depth tool to make it possible to move a pinion to a different case. Then in the ideal world use a solid pinion spacer vs the crush spacer...
I've set up a lot of Diffs, and want a giken for mine. It's just accepting that having the lexus badge doubles the cost and when on sale it's just a buck fifty less.

Anywho... LSD group buy anyone?

redspencer

iTrader: (1)

No worries 2013FSport. I like having this thread open to performance-minded discussions within the 2IS community as we find new ways to further improve the platform.

Last Friday, I went to the Lexus service center to finally complete the two-plus year long journey of getting all of the sticky door panels and center dash replaced. As I had the center dash and front door panels finally replaced last year, I patiently waited for the rear door panels to be in stock which they were a few days ago. Thankfully, with all panels fully replaced, the interior looks very sharp and restored.




Unfortunately, all is not rainbows and sunshine as on my way back home from the Lexus service center, I heard a very loud thunk sound on the highway and my IS350 had suffered its first windshield chip damage...



The chip and crack is slighly larger than the size of a quarter and as I type, I currently have a technician from Safelite Autoglass in my garage attempting to make the repair. Hopefully, the repair will be successful, mostly unnoticeable and will not result in having to replace the entire windshield. We'll see.....
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EDIT: Some real-time updates for this thread. Though it cost me over $100, it looks like the windshield repair was a success. The crack was filled and the impact area looks like a small water drip so it's almost unnoticeable. Hopefully, these types or repairs won't have any issues when I take the IS350 back out on a track at 100+ MPH.

redspencer

iTrader: (1)

With a previous topic regarding maximizing air flow and MAF g/s datalogs, I had been under the impression that for the 2IS intake system, removing the charcoal filter from the OEM intake box would result in either no performance gains or may actually reduce horsepower by a slight bit. This was tested by one of our CL members doing several dyno pull tests with and without the charcoal filter and it resulted in a slight loss of horsepower with the filter removed. Keeping the charcoal filter is also the common thought process within the IS-F community.

Youtube channel Engineering Explained recently released a video comparing the dyno and acceleration results using different intake filters (OEM vs K&N) and either keeping or removing the charcoal filter. Both the dyno and acceleration results favored the intake system with the charcoal filter removed. Logically it makes sense (less potential restrictions) though the latter portion of the video attempts to explain that the improvements would be negligible and it would be best to keep the charcoal filter. As my IS350 is getting closer to reaching 100k, I can only assume that the non-replaceable charcoal filter is probably doing more harm than good with restricting airflow from the years of absorbing hydrocarbons and yanking it out may be my next mod.

MikeFig82

iTrader: (13)

I bought a replacement oem one from eBay. The the charcoal panel was so filthy. I used car wash soap the clean it out. Just lather it up an let it sit. Then rinse and let it air dry. Heck since I'm off today I'm going to go clean it again.

I see no problem washing it. I've done it in the past to my original before I gutted it out. I feel with out it it does breath better on the top end. Low end it feels like you loose a lot of low end acceleration.

2013FSport

iTrader: (2)

I sprayed a good bit of maf cleaner through it, gently scrubbed the filter side with soft brush, more MAF to back flush and blew the rest through with compressed air from the back side.

redspencer

iTrader: (1)

Thanks for the idea of cleaning the charcoal filter vice removing it. I'll eventually do something about that filter since it likely has the same crud stuck to it since the day I drove the car off the lot.

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Well......this has been an interesting past couple of days for me. Not only did the IS350 get its first rock chip on the windshield (which was thankfully remedied), the IS350 also received its first flat tire. If bad luck comes in threes, perhaps I should keep the car in the garage the rest of this week! As I left the garage this morning, the low tire warning light illuminated. Luckily the drive back to the garage was a street corner away as the rear tire only had 8 psi. Upon inspection, I found a nail wedged near the center of the tire. It probably didn't help that the tread was right at the 2/32 wear bar limit.



On the plus side, I made a call to Discount Tire and placed an order for a new rear set of Michelin Pilot 4S tires. Luckily, there was a set at a local distribution center so I had to hold out until the late afternoon to get rid of the punctured tire. Though it was a bit stressful to keep inflating the damaged tire 10 psi every 4 hours to keep the pressure at 40 psi, I managed to pull through and get the new PS4S tires installed this evening.

Though I've only had a few short miles with the new PS4S, the level of grip in the rear definitely exceeds a worn set of PSS tires. I plan on going to the track this spring so I'll have a good opportunity to see how the PS4S tires do in combination with the LSD. It's nice to have meaty treads on the rear again (as I've delayed getting the PSS tires replaced since a tire replacement every 15k miles is expensive). The PS4S treads look very similiar in design to the predecessor PSS treads but hopefully the new model will perform and last incrementally better than the PSS version. Here are a few pics of the new shoes...

Gville350

iTrader: (10)

Bummer about the windshield and that nail! Besides the horrible pitting across my OEM windshield from the previous owner, I've been able to avoid all rock chips and cracks...crosses fingers. I've found my fair share of nails and screws in my Lex. I even patched one myself when Discount Tire said they'd not touch it, even though it wasn't on the sidewall. Good to have a good mom and pop shop in your pocket to do your tire work that Corporate chains won't touch. This includes "flipping" tires to maximize treadwear on your symmetrical tires.

So what is supposed to be the difference between the "old" PSSs and the new 4S? Compound? Tread looks identical! LOL!

redspencer

iTrader: (1)

I remember the days of flipping my tires to the other side to maximize tread life. I miss my old BFG KDW2 tires. They were noisy but they had huge tread patterns!

From the information I read up on the past year or so, the Michelin PS4S is a smaller improvement over the PSS and is less of a generational leap than the PSS was to the PS2 model.

For dry track conditions, there are supposed to be less hot spots on the PS4S when the tire is under heavy load compared to the PSS which will help keep the tires from feeling greasy a bit longer. The overall tread life is also a slight bit better than the PSS as well.

The wet track conditions are where the PS4S tires supposedly see the biggest improvement over the older PSS.

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EDIT: I did find this article from Motor Trend that compared lap times from their long term BMW M2 with both the Michelin PSS and newer PS4S tires:
https://www.motortrend.com/cars/bmw/...term-update-4/

For being a short technical course, the M2 was a full 1.44 secs faster with the new Pilot Sport 4S VS the factory Pilot Super Sport at the Streets of Willow 1.6 mile race track!

Here's another direct comparison review:

mike33

iTrader: (1)

Any reason you didn't replace the windshield instead of repairing? I thought in Florida insurance was required to replace damaged windshields with no deductible or cost to you...

BTW, I have really enjoyed your thread over the years, its full of great information. Thanks for keeping it going.

redspencer

iTrader: (1)

For $100, I thought it would be worth attempting a professional repair to the windshield and keeping the insurance company out of the equation unless the chip was deemed to be unrepairable and would require a windshield replacement.

As I still wanted to keep the factory-installed OEM windshield, I wasn't sure if getting the insurance company involved would result in a few unforeseen negatives:
1) Result in a flag on a Carfax report that the car was damaged (particularly for something as insignificant as a rock chip on a windshield).
2) If the insurance company insisted that the windshield be replaced instead of repaired, would I be receiving an aftermarket "OE-Equivalent" windshield instead of another OEM Lexus windshield.
3) Potential issues from a bad windshield replacement installation such as water leaks, wind noise, etc. from an improper seal.

Glad this thread is still of value to multiple CL members. though new upgrades to my IS350 have slowed down, I'll still be experimenting with modifying certain aspects of the vehicle for further refinement and improvements and taking the Lexus to the track for some fun while observing what else can be improved to the IS350 and myself as the driver.

Though I'm still eyeballing a new garage queen to add to the collection (tentatively a Porsche 718 GT4, a Lotus Evora 400, or the rumored top-trim GRMN A90 Supra), the IS350 will still be the car that I'll continue to enjoy as my daily driver and regular track use.

DickH

I like my IS350. Part of me wants to abandon my other car as a project car and turn the Lexus into something a little more fun. On the other hand, I like the car and it's a great daily driver and I would hate to take away from that. I think what redspencer has done with his is nearly perfect. Another 50hp and the IS would be perfect. I've been wanting to dive into the suspension but I am waiting until the car needs it. Maybe adding an lsd would help persuade me into needing to upgrade.

As for buying a new car, I really wouldn't mind a gt350 or for some reason the BMW M2 is appealing, but I'd never buy one. I can afford the payment on a new car, but I just have a hard time justifying it as I like to tinker and would prefer not to void the warranty on something that expensive.

2013FSport

iTrader: (2)

Windshield - about 2 months ago it took a hit just above the mirror and to the left about 2mm from the edge. It instantly took off downward and hard left.
2 weeks later another star is born hitting just below the existing crack dead ahead of the passenger. They mated instantly with that crack heading straight down.

Glad I didn't replace it then and waiting for winter to pass. Which in this city is pointless as they swept the interstate in December just to gravel it 2 weeks later when it snowed. If history repeats, they'll leave that gravel for 10months to break more windows. City and window companies working together???? lol

But ya, I'd like an OEM windshield. Doubt that's gonna happen.

As stated by others - a nice living thread.

redspencer

iTrader: (1)

Now that I finally have a new set of rear PS4S tires (which are noticeably stickier than the PSS tires as it tends to fling more pebbles into the rear wheel well liner and tends to tramline more often), it's time to have fun with the car again.

Last year in April, I took the IS350 to the dyno to see how much RWHP it could make with my previous setup (PPE headers, RR Racing Tune, F-Sport Intake and Exhaust, OEM stock midpipes). To my disappointment, the IS350 did not make the numbers I thought it would make with that setup. I anticipated a result of 290-300rwhp but instead was left with 282rwhp as noted below from last year's dyno sheet:

April 2018

A few things were learned from this dyno experience:
1) The skinny OEM midpipes were a potential bottleneck to the exhaust flow which may have severely restricted gains at the higher RPM range.
2) I had the ECT set to PWR instead of SNOW which made it impossible to get an accurate reading below 4.5k-5.0k RPMs.
3) I later learned from doing datalogs that my peak ignition timing advance was at 27 degrees.

There will be a temporary cold front coming through Florida next Wednesday and I plan on taking advantage of the cool dense air by taking the IS350 back to this same dyno shop to see if there will be any improvements to the peak horsepower at the upper RPM range. These are the changes that will impact this upcoming dyno run:

1) The IS350 now has 2.5" midpipes which should resolve that exhaust flow restriction.
2) ECT will be set to SNOW and 4th gear will be recorded at a much lower RPM once the speedometer reaches 55mph which is when WOT can commence.
3) ECU Tune has been revised for the ignition timing advance to peak at 30 degrees. I've also blended the fuel mixture to E30 earlier today to minimize the potential for any knock or detonation from heat soak while the car is on the dyno.

To further improve air flow (based on the data provided on the Engineering Explained video that I posted on this thread in February), I decided to remove the intake carbon filter from the intake box earlier today. You can see how filthy it looks after being used for 95K miles:



Here's how the carbon filter looks like when you pull it apart:


Here is the upper intake box with the carbon filter removed:


I also used this opportunity to spray down the MAF sensor:


Unfortunately, I accidentally broke off the plastic tab of the connector that attaches to the MAF sensor. It must have been brittle due to the years of engine bay heat.


Because of this, I have to use a ziptie to ensure that the connector doesn't pop off accidentally while I'm driving. Is putting on a new connector tab an easy fix?



I did several WOT pulls earlier today to see if the datalog would record an improvement with the intake carbon filter removed. To my surprise, the MAF g/s reading at 7200 RPMS was recorded at 248 g/s with an Intake Air Temp (IAT) of 82 degrees. Previously, I'd record MAF g/s #s in the upper 240 range when the IAT was in the upper 60s/lower 70s so to see this number while the IAT was in the lower 80s was surprising to say the least.

DickH

Good luck on the dyno, you have to clear 300hp this time. I went back and looked at your posted maf numbers and it looks like you picked up ~6% more airflow. That alone should put you on the 300hp line, with the timing adjustment putting you over.

​​​​​Which intake are you going to run on the Dyno? You should try a run where you flip the lid to the air box to reduce that restriction.

MikeFig82

iTrader: (13)

I found some throttle body stuff on the tundras forums. They take out the TB gasket, and replaced it with a non grilled version. Months back I got an extra gasket, and cut out the metal grill out.

Now I've searched for days and couldn't get a definite answer to the purpose of it.

The Tundra guys remove it, because when they get intakes they getting a whistle noise.

What I found out it makes the throttle induction more noisy. So I don't know if it's letting more in or what. I could hear the noise inside the cabin. So I took it off again, and put a replacement back in. I would wonder if you would see any maf g/s increase with out it.