To tune, or not to tune? That is the question. Manual transmission.

Oh yes yes, we talked about this already!

 

Correct me if I'm wrong but, rev matching has little to do syncro wear. In order to save syncro wear you would have to double clutch.

Think about it. If you're reving the engine with the clutch disengaged and you are already in gear. The syncros have done their job, you went past them already. There is no mechanical linkage between the engine/flywheel and the transmission with the clutch disengaged.

 

Very informative video.

Explanation was simple and effective.

I can honestly say, I've never practiced/put into practice: revved-matching.

 

Thanks!

Race car drivers use heel toe/rev matching technique so they don’t lose time and to avoid using brakes. Using brakes on race track shifts the weight of car forward, don’t want that in sharp turns at high speed.


It’s good to let’s say keep momentum when driving up hills at full payload trough mountain passes. You are instantly in a lower gear, maybe 2 and in the power band and ready to go. That’s when I use it the most.

Also, if I’m going down steep hills in town, I revmatch downshift so my clutch/syncros don’t do any work and i save my brakes that way.

It’s soo satisfying when you get that perfect revmatch.

 

I think you are right on that one. I do double clutch revmatch when going down more than 1 gear to save my syncros. Yes that make sense, thanks for correction.

So to clarify, to save syncros from
Wear, double clutch is the answer.

 

I'm envious.

I mean that seriously, not as a slight. I say it because the Tacoma is bar none has the worst engine of any vehicle I have ever owned. The power delivery and throttle response of my truck is on par with my old 90s 2-strokes when they were about to foul a plug. I don't mean that as an exaggeration.

To be clear, I don't hate my truck, I love it.

On top of that the difference between my 21 Tacoma and our 19 Highlander is night and day.
I have even monitored for cylinder misfires because mine is so bad. It distinctly feels like a cylinder randomly dropping out when accelerating.

So when folks say they don't feel anything (and my highlander is so nice) I REALLY question if something is wrong with mine. Still, I have described my complaints here and my experience echos many others.
That said, if you don't notice anything I truly am happy for you.

 

It's definitely got some quirks, as seen on the dyno charts in the tuning threads, but I think I've adjusted to it. I mentioned earlier in this thread, but this is the only vehicle newer than 1999 that I've ever owned, so my expectations might be different than some.

If it's less than 1500 RPM's, I don't expect anything from the engine, it needs to be downshifted or throttle has to be at like 10% max.

If I want to hammer down, I wait until 3500 RPM's if I'm going wide open throttle, or even 80%+ throttle if I want any power to be smooth.

Everything in between (where it lives 99% of the time) is keeping it between those two RPM's, with I'd say throttle around 20-40% on average (guestimate). Runs smooth as butter.

Honestly not all that different from my previous manuals. They don't do anything below 1500 RPM's, and the power is all at the top (all 4 bangers and v6's).

I'm genuinely curious as well if these trucks are actually as different from one to the next as they sometimes sound, or if it's the drivers having different expectations. Like I said, if it wasn't for this forum, I would never have thought twice about the accumulator nor a tune. It sucks that not everyone has had the same experience, but I'm glad to hear that you still like your truck.

If anything, I'd like to try the ADM. I'm sure I'll order up one of your disks this summer to test it out, thanks for putting those together.

 

I truly love the drivetrain in my taco, it was great even with stock tune, never a stumble/misfire/hesitation, press the pedal and she goes. I’ve always used 91E0 gas so maybe it helped. 4.30 gears work great IMO.

Now running 94E0 with a performance time and the truck drives amazing. Good low end and the engine is very smooth. I look for every excuse to go for a drive.

My previous vehicle was a 2007 ford ranger with a 4.0, miss that truck dearly. In comparison Tacoma is like a rocket ship. Man, miss that cable throttle. Awesome revmatches!

 

90% of my driving is 1500-3600 with occasional low RPM (1200-1500) cruising, and the occasional on-ramp. In this range (1500-3600) even lightly rolling into the throttle has it bucking and feeling like it almost has a miss. This isn't the power dips and uneveness seen in dyno charts, or I don't think so, as it does not seem RPM based and is instantaneous, again, like a misfire.

Above 3600 this goes away and the engine is fine, aside from an ugly throttle hang.

I have monitored my computer and what I see from a fueling perspective is a strong tendency for the computer to be subtracting fuel while cruising, then as I roll into the throttle (lightly mind you) it starts adding fuel. Then at a certain point the LTFTs lock out, usually around 3-6% added fueling. After this point is where the engine gets rough, and I have to say it feels like it is lean, which would make sense considering the computer was trying to add fuel and then suddenly stops. I'm not an expert on tuning these so I don't know why my fuel trims lock out at such a low level and at such a low load setting. I would say vacuum leak but that should be worse at closed throttle and get better as you open up the throttle, this seems the opposite.

Thanks for the thanks! If you do get it I hope it feels like an improvement for you but I'm happy that currently you don't feel you need it!

 

I'm really considering a re-gear, even being 99% stock. Please don't tempt me...

I have monitored the computer with every grade and style of fuel. 87, 89, 91, 93; cheap speedway, shell, even top tier in high octane. I never noticed a difference on any of the fuels, none. And monitoring fuel trims and ignition timing there was never a change. I fully expected a change in timing when running premium and even when plotting peak timing against load nothing changed, ever.

I don't get it...

 

All my Japanese brand vehicles seemed to have more power and get better MPGs on 91E0+.

I think 4.88s would be absolutely perfect running 33s. I’m on 33s now, first, second and R could use 4.88s, otherwise it’s great. I do have 2WD low mod, it’s a game changer.

 

I was surprised when I couldn't find any difference. I'm in the camp that premium doesn't have much of an effect but I expected to see or feel SOMETHING.

For me 1st is halfway between short enough and long enough, 2nd is too long, and going into third just removes any of the fun. Reverse isn't an issue for me but all I do is back out of the garage, I can see how it is annoying for anything serious. I do also wish first in lo was a bit shorter as well, I have 6 gears but feel like I would hardly need two

 

Here we are telling you our experience is that it should be on the top of your list, you’re on this thread justifying having it at the bottom of your list… get with it and and get a tune already.

 

Heel/toe is literally brake application while downshifting. I can also smoothly rev match while down shifting with an unmodified accumulator in place. It's not difficult at all. It's not as easy as the Cayman it's garaged next to, but it isn't impossible at all.

 

This is really well said. This is my first Toyota. 21 TRD V6 MT. 12k miles. The ECU mapping is profoundly bad. I think the power delivery can be corrected. At higher vehicle speed, the lump actually delivers SOME torque in 5-6th gear. I drove it through the mountains yesterday and was surprised by that oddly bold display of Briggs & Stratton mower torque, so its there, whatever “it” is worth in terms of ft lbs. the rest of the truck is really well done. I wish I could dumspterize everything above the valve covers and screw on a DFI. Hell, a Holley and manual choke cable would be a vast improvement. Being down this road with a couple of jeeps, the Magnuson / Eaton blower will end this and hang some balls on the 1500-3500 rpm range. Tuning is the big hassle. I dunno much about these Toyota engines yet. I do know that your post expresses my experience exactly perfectly.

 

My "cruise rpm" floor is 2k. If you are below that IMO you are too low, though I can add throttle (no mashing the pedal) below 2k without any bucking. If you have issues between 2500 - 3600 rpms there is a problem somewhere.
You definitely need to re-calibrate your rpm reference though, this engine isn't a lugger.

 

With a manual I should be able to run 55mph in 6th gear. I don't remember what RPM that is right now but I'm fairly certain it is below 2000 RPM.

Torque at low RPM is different then drivability and I should be able to comfortably cruise with the engine below 2000.

 

“Should” Definitely. But they map these things to pull fuel and timing back at low RPM -Part throttle. So much so that they fall on their face a little. I was absolutely surprised at how conservative the mapping is. Its not like these engines have 427 Ford cranks swinging work boot sized connecting rods, throwing 4.75” pistons long and far. None the less, these engines can be improved. It sounds like they respond to a properly mapped tune really well. I just wonder what the hell the factory code developers are thinking.

 

Well this thread is old and dead! Traded my 2020 Pro for a 2023 Pro in solar octane with the manual transmission. Got the manual tuned after 3 days of having it because I already knew how much low end torque and drivability I was missing out on as I had my 2020 tuned for quite a while and I believe it’s the best mod for the money by miles. It’s amazing in the manual as well, having low end torque and not having to rev out so high is nice. Next is the accumulator delete.