Max Speed Issues A/T Car (Limited). Need Advices
 

Hello Guys!

I have an FRS 2013 Automatic ZA1JA00D for US Market. I have an OFT v4.03 Stage 2+ of the shelf installed (Tomei UEL, KN drop, Nvidia N1 catback) with only one tweak, that is not necessary to the problem by itself, which is Removing Speed Limiting A/B(Throttle) after 130 MPH (set to 170). Thought I would mention this.

So the problem comes with a WOT and max speed capacity. When Ive just bought my car back 3 years ago, with a bone stock I was able to reach 230+ kmh (143 mph) without any issues with Sport mode and VSC Track enabled. I didnt pay attention to the gearing and else and was focusing only at driver experiences.

After a few years Ive decided to go OFT Stage 2+ and added the listed above mods. Ive already made about 3-5 reflashes since I wasnt aware that I need some time to adjust the tune to a car (200+ miles) before WOT and hard driving. The last reflash went all correct with and everything is at normal conditions. Ive logged IAM and it stays at 1 (using 100 gas) and never drops below that, which actually Im surpized since the tune should start it from 0.7, but thats not a problem.
I went to a backroad where I did max speed pulls and WOT similar to what Ive tried at bone stock car. Ive made barely 205 kmh at max only once and other pulls were from 201-202 kmh (127 mph) range.
After Ive read the forums and reviews of A/T its being said its limited to 127-130 mph (redline rev limit) and unable to bring more.
That comes really weird compared from what Ive seen at the beggining. To make sure Ive made some other tries with a more cold weather temps, but resuls were absoulutely the same. Ive started to investigate the problem and found the issue was gearing in both D and sport Modes.
Here is what Ive found as a WOT example for Auto cars:


[ame]https://www.youtube.com/watch?v=F6gG-SFdABI&t=112s[/ame]


Pull starts at 0.42 sec of the video. Thats a low boost turbo car, correct, not N/A, however his gearing in D mode goes straight into redline at every single gear! My car in sport mode does the 1-3rd gears at rev limit of 7500, right after that it starts to shift every 20-30 kmh to a next gear, 5th from ~170kmh (~5.5-6k rpm 4th), 6th from 200kmh (starts wtih 5k rpm) barely with a 5k rpms and not capable to move any further after that. Ive tried manual M mode, whereas I was able to reach 200kmh at 4th gear but wasnt able to continue due to the road conditions for those moment. The proof its able to do 200 in 4th gear without a sweat making me feel the car is okay itself and there is no exhaust leaks or whatsoever tech related issues.

For all of a sudden, car was doing differently, close to whats shown at the video. Im not sure what to do with it and how to return it back to this conditions. Im aware there is no possibility to edit TCU, but the only thing I was able to find related to this is a Draw-by-Wire table, which can effect the shifting requests from ECU to TCU. But I dont feel myself enought confident to play around blindly in the dark. Ideally I would want to leave D mode as is and adjust this settings to Sport mode.

Can you please suggest why that went different from a Stock bone car with a modded one with OFT? How I can return in back to an old gearing logic? Please help me out because Im super frustrated about that.

These cars are drag limited in stock form to 135-140mph, and accelerating in (5th in auto)(6th in MT) at 128mph+ you arent going to increase speed very quickly. Just don't have the power to overcome the drag forces. also wind speeds that day can make a big difference. Look up max speed runs autobahn.

Thats what I know, however my car is switching gears too quickly in both D and Auto right now, making it not able to move after 201-202 kmh further ending at 6th gear with 5k rpm where its not possible to move any further at any distance, it can run 2 miles/3km straight away without speed increases from this point. Weather conditions etc isnt the case for sure here.

The car doesn't have the power to increase speed in 6th at 5k rpm. Autos have the gearing to hit i think 212mph, manuals i think 178mph. But not the power, at a certain point the power needed to maintain speed will equal the engine maximum output and only be able to maintain not increase speed no matter how long of road you have.

You will hit “top speed” long before hitting redline in 5th (for autos) In fact you will hit top speed around 6k RPM in 5th gear. If your in manual mode the car shouldn't shift if in auto it may see the lack of acceleration/speed increase and be programmed to shift into 6th to maintain “cruise” speed.

Yes it is. But thats not specifically related to the problem described in topic. Vehicle was capable to do differently.

The video you posted he is turboed (way more power then bolt ons let alone bone stock) and he only gets to 5.5krpm in 5th at 138MPH he doesn't touch 6th, maybe with longer road he could have slowly crept up to 143MPH in another 30seconds.

There is no way you hit 143MPH bone stock, its not physically possible unless on a massive downhill road, i suspect you have no issues at all and are just miss-remembering the speed you hit bone stock incorrectly.

A top speed of 130mph with bolt ons is normal for autos that is 5150rpm in 5th gear. 4th gear normally tops out at 124mph(200kmh) then shifts into 5th dropping RPM down to 5k rpm, and then you slowly creep up to 5150rpm or 130MPH as the gearing in 5th is way too long and the power is way to low to continue to accelerate. It just falls flat on its face, and will slowly creep up to 130mph if given enough time. 100% normal for NA AUTOS even with bolt ons.

Also 6th gear at 4250RPM is also 130mph.

If you refute any of this Why not film a video of your dash to show what you are trying to describe then.

Thats all correct, but he is in D mode, not the manual with shifters! How the fuck D A/T basic mode keeping 5.5k RPMs at 5th gear.

I kinda dont understand why mine both D and Sport A/T mods are switching to 5th at 180 kmh (110 mph), then at 125 mph it turns to be a 6th immediately. Ok generally you covered the point and lean on not enought power, but it was doing up to redline at every gear instead of switching that fast. Ok, if you are strong believer that things are alright, lets not focus on speeds at this point, yet only RPMs. So your car being AT can hold up 5th Gear up to 5.5-6k RPM? Why the fuck mine started to switch to 6th at 4.5k RPMs going WOT?

Im 100% sure it was capable to do so, I had a passenger with me and he confirmed the speeds. Ive reached roughly 230 or 231 kmh even with a passenger on D + Sport Mode. I will think about the way to do video safely, but not something I can come up with too quick.

I should correct myself, 4th tops out at 128mph, and 5th at 5100rpm is 128mph, at 5200rpm its 130mph, 5300rpm is 132mph which is the fastest you'll ever get in a NA AT and it'll take probably 20seconds WOT from 128-132mph so you need a long stretch of road.

I can hit top of 4th in any mode, D, D+sport, or manual mode as long as I'm WOT doesn’t matter. Ive gone 130+ like 2 times as i don't see the point. But it stayed in 5th until i let off both times.

Assuming you have stock final drive and are WOT it shouldn’t shift from 4th to 5th before at least 124mph. If it is I'm not sure. You only have bolt ons you could flash to stock and test it with stock tune.

This shouldn't apply to 4th gear shifting early, but i could see with NA power that around 5200-5300rpm in 5th based on various load parameters and the lack of acceleration that it’s automatically shifting to 6th thinking your “cruising” at 130mph.

But try to record it and or flash to stock tune and try again.

But it is 100% physically impossible for a NA auto to hit 230kmh/143mph unless your going downhill with the wind pushing behind you.

Now you got the problem all correct. Yes it shouldnt shift but it does. The thing is before the bone stock at very beggining, I had an issue with a cell code, it was P0391 camshaft sensor position, so from time to time I was getting a cell when I was doing WOT, sometimes very often. Before I went stage 2+, Ive ordered official shims to camshaft position sensor. You seems not aware about the issues since you do have a newer car. So the official fix at Toyota`s diller was to order shims, so I did that. Shims come in a pack of 10items, whereas youd have to pick one of those sizes that fits specifically a certain car, they ranged from 0.5 to 2mm. I had a lowest possible distance so 0.5mm fitted my case. Firstly, they installed not the exact thinner one, but slightly thicker. To my surprize, car felt like it was lacking power significantly, without a doubt that also indicated the problem with a top speed right after, but it was doing way differently, while I was able to reach 199kmh it was constantly switching from 5 to 6 speed itself and the speed was 199/200 kmh, I was shoked. Right in a while cell triggered again, we changed the shim to a proper one and never had any issues afterwards.

Im aware now that OFT Stage2+ has this sensor disabled, so Ive tried both options with the shim or without, but it doesnt make any differences at all. Flashing back to stock is definetly possible, but actually I had prety the same case at stock car after the fcking shim. I do believe maybe its their computer after they connected it at Toyota it might changed something, who knows. But flashing back would help to resolve the issue. So the problem is complicated. Im not sure what to do honestly, apart maybe to ask them to investigate TCU or whatsover, Im frustrated about the case overal so hard.

I was thinking things over and realised I have to find the answers on why overal gearbox in AUTO mods doesnt hold the RPMs, meanwhile manual mode does all around well. Any ideas?

The automatic trans is going to shift using calculations from MAF, engine load, tps, have you raised your engine load limits A & B?

http://www.ft86club.com/forums/showp...postcount=2510

Thank you thats much appreciated, I cannot find Engine Load limiter A/B, I didnt touch MAF either coz I dont understand how to do it, specifically. I do see there is a MAF Scale table with the reduced Numbers, should I try that as well. What is TPS ?

"A throttle position sensor (TPS) is a sensor used to monitor the air intake of an engine."


;)

humfrz

^ I thought it worked off throttle position?