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After patiently waiting over a year and a half and having to decide on alternative brand tires over my current Michelin PSS, I'm happy to note that Michelin finally has the newer PS4S tires in my current rear tire configuration as of this week (275/35/18)!
As my rear tires are right at the wear limit, I was contemplating on picking up a rear set of Firestone Firehawk Indy 500s or the General G-Max RS as the price is inviting but since the new generation of Michelin Pilot Sports are out for my size, I'll be going with those and I'll post a review once I install and break them in.
I've heard awesome things about the Firehawk Indy 500s - especially for the price. I'll be running them on my IS350 in the future! Can't wait for your review on the PS4S though.
I've heard awesome things about the Firehawk Indy 500s - especially for the price. I'll be running them on my IS350 in the future!
They're good when new and mid-life; but on the second half of their life they go down hill quick regarding their ability to grip. But this was my experience and I was heading into fall/winter with colder temps. So you'er basically getting what you're paying for I guess.
I'm now on PSSs now (255/30/19), earlier than expected due to a pothole causing sidewall damage (the Federal tires held up better on the same pothole!) and though the temps have been in the 20s and 30s, they're still a solid tire and once on dry pavement and temps in the 50s, they'll hook!
Looking forward to your review on those new tires Red!
I've heard awesome things about the Firehawk Indy 500s - especially for the price. I'll be running them on my IS350 in the future! Can't wait for your review on the PS4S though.
Yeah, plenty of my car enthusiast friends run Indy 500s and they too love the performance-per-dollar that it offers. During my research into the world of UHP tires, the Indy 500s offered the best dry grip in its category while the General G-Max RS tires were a close second. Wet grip performance went to the G-Max tires as well as weight savings (2 lbs lighter than the Firehawks).
I'll be back on the track in February or March so I'll have a good opportunity to see how the PS4S tires feel when loaded. I'll still have PSS tires up front but the compound differences shouldn't be too different to cause any issues.
Also to note, changing the front toe setting to zero has drastically improved the tire life up front as I would usually wear down the front tires to the inner treads by 15k miles.
Originally Posted by Gville350
They're good when new and mid-life; but on the second half of their life they go down hill quick regarding their ability to grip. But this was my experience and I was heading into fall/winter with colder temps. So you'er basically getting what you're paying for I guess.
I'm now on PSSs now (255/30/19) and though the temps have been in the 20s and 30s, they're still a solid tire and once on dry pavement and temps in the 50s, they'll hook!
Looking forward to your review on those new tires Red!
Thanks for confirming what I had wondered about the Indy 500s. I've read numerous reviews that these tires can get squirrelly in the rain when they are half-worn but it sounds like it's the case when it is dry with cooler temps. As tires are the only items connecting the vehicle to the ground, sometimes it's best to not skimp on the right tire.
I didn't know you had gone through your Indy 500 tires already. Glad to hear that you're noticing some additional benefits from the PSS tires even though they carry a heftier price tag.
Last May when I took my IS350 to the newly built Lexus of Orlando service center to get the sticky door panels replaced, I snapped a pic of my car at the waiting area as this was a brand new facility and I liked what they had done to the place. I posted the picture on Google Maps and forgot all about it until this morning when I received the following notification:
I guess the general public finds the pic to be eye catching.
Here's a PSA on a potential upgrade for improving the shift speeds on our A760E transmissions. I noticed that RR Racing had posted the below on a different thread in response to a comment from a 3IS AWD owner with their laggy 6 speed transmission:
Originally Posted by RRRacing
The TCU is not really going to improve shift feel or shift quality. For that I recommend removing the valvebody and installing a shift kit. This consists of minor upgrades intended to increase fluid pressure during shifts.
We are working on valvebody mods to improve shifting and hold more power with the superchargers.
Rafi
After inquiring further on this with Rafi, he mentioned that there are valvebody upgrades already available for the A760E. Though they haven’t tried them out yet, if anyone is local to their shop (Pennsylvania), they can contact the shop and get these components installed which should be a great improvement to the transmission.
Is anyone in the area willing to give this long-awaited upgrade a try?
FWIW I drove a 2017 IS300 AWD with our A760 trans. It had zero paddle lag. That said and from 6 years working at a transmission shop, although jacking the line pressure will make the shifts quicker, there is a soon a point of diminishing returns as this increases wear and raises the transmission temp if excessive. Not to mention a pressure sensor and solenoid driven by the TCU are controlling the line pressure.
What I would want to know before doing this is IF the trans is actually being given the commands to the solenoids to shift? If not, valve body pressure fixes are not the correct solution.
If however the solenoids do act to shift instantly, than yes, a valve body fix is in order.
There is a lot of info on this trans. Just not a lot of fix for our application.
Edit: Something I left out of the first post, as the power levels go up (boost etc), there is a need to increase line pressure to prevent slippage. In this realm, you need to increase pressure to increase clamp force internal to clutch packs and drum bands.
But unless we are making more power, there is no need to increase the line pressure if the shifts are crisp and direct. i.e. not slipping or flaring.
What I would want to know before doing this is IF the trans is actually being given the commands to the solenoids to shift? If not, valve body pressure fixes are not the correct solution.
I've been wondering the same thing. What I suspect is that the trans in our cars has the capability of accepting the shift commands, but the paddles are not sending that command, but instead are just sending a command to change the gear lockout value.
I've been wondering the same thing. What I suspect is that the trans in our cars has the capability of accepting the shift commands, but the paddles are not sending that command, but instead are just sending a command to change the gear lockout value.
Likely not the paddles but the trans TCU or integration of ECU to TCU. i.e. the two must agree so as not to do something stupid like over-rev the engine.
H$ll it could be a lack of computing power but I doubt it?
I received an updated tune from RR-Racing today which will advance my ignition timing up to the 32-33 degree range. Hopefully I'll get a chance to revisit the dyno shop while the weather is a bit cooler (still fairly rare in Florida) as I'm curious to see how the car fares now that it is FBO+tuned.
On a side note, looks like the new A90 Toyota Supra has finally been fully unveiled in this Toyota Promo and is still my top choice for a new weekend car that I am considering getting to add to my garage:
Video not available for some reason bro
Good to hear tuning is coming soon for your car, today mine got a custom exhaust and made the intake cold box too. Notice a little bit of torque loss on the low end due to the change of exhaust diameter( 2.5 now) but hopefully when it gets reflash that will improve.
Update: video is now working for me
Last edited by Marn1; 01-10-19 at 08:22 PM.
Reason: Video now working
Just saw the release coverage of the new supra. 335 HP 365 TQ 3360lbs. I don't know, seems very 370Z ish for me, except more upscale in interior, better styling on the exterior, and obviously more torque because of it being turbocharged. It's reported to have a lower center of gravity than an 86 though, which should make it fun in the corners.
Not trying to derail your thread into a Supra discussion but I thought it was worth mentioning
Yeah, I watched the Toyota Supra livestream this morning and was lukewarm with the unveiled USDM specs. Though Akio stated that the Supra will do 0-60 in 4.1 seconds (which either means the flat torque curve makes a huge difference or the engine horsepower rating is severely underrated ala BMW), I'm disappointed that Toyota had chosen to utilize the detuned 335HP B58 engine that the Euro/Japanese market will receive (which utilizes a heavily restricted emissions filter) instead of the unrestricted B58 engine that the USDM Z4 will utilize (making 382HP). My guess is that Toyota will revise the engine specs at a later model year with the 382HP B58 version.
As a highly active member on the SupraMKV forums, it is all but confirmed that the Toyota Supra that was unveiled today will essentially be equivalent to the old naturally-aspirated 93-98 Supra of the MKIV era as a more potent model is in the works (TRD/GRMN) and would be the MKIV TT version of the new MKV era. This is the trim that I am keeping an eye out on (and crossing my fingers that it won't be released in an extremely limited quantity like the previous GRMN models released by Toyota/Gazoo Racing).
12-13-18, 12:24 PM
