SMF + Phearable 1.5R and still have rev hang?

[borcth]

Hey guys, so I'm FBO, RV6 retrofit flywheel w/ Stage 0 Clutch. The car was retuned about a month ago with the Phearable 1.5R w/RACE MAF. The car over all drive great and is smooth. However, especially when it got cold recently, I noticed upon a cold start, the rpms would jump between shifts as I began to drive. Almost like rev hang, but rpms dropped quick because I'm SMF flywheel now and as far as I know, rev hang is removed via having Main in OFF mode. Once the car is fully warmed though up it's a lot less. However, daily driving when it's warm and weather is nice, I notice a slight jump during a shift or when I go into neutral. More noticeable in the lower gears. I watched the throttle % on ktuner and it'll say zero as soon as I let off the gas to shift. So throttle is not staying open between shifts. I'm not sure if this is slight momentum from the flywheel from disengaging the clutch or what. I don't remember this happening prior the new tune. Perhaps it was, since I've had the clutch 2-3 months before the new tune. Maybe it's just a placebo effect and always has done this. I was on Phearable 1.5 street and stock maf. I tried turning rev hang off/on and feels the same by the way. It doesn't seem to do it all the time but I'd say more so than not.

Also, I notice that when I use the defroster and it's blasting on high, there is a hesitation during shifts. I notice the battery voltage go up/stay up until I turn it off. Also happens when the normal A/C is on high. Now I don't usually blast it or use defroster. But since it's been colder and windows fogging up like a mofo I've had to use it more often. Seems like a high power draw. I'm just curious as to what is causing these things and if it's normal. Is it the tune and it's normal and not to worry about it? Just small quarks and I get OCD about it.

Any insight on this is much appreciated. Thanks.

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[Chaucer]

It could be a few things.

Do you a have a 2020? If so, Phearable leaves revhang enabled by default in the tune, so you’ll have to uncheck that box and reflash if so. If you do have a 2020 I would leave it enabled and try to remove it with the new throttle sensitivity option.

On a cold start the car will have a higher idle to light off the catalytic converter, which can feel like rev hang.

Lastly, even with rev hang disabled, I’ve noticed that revs fall slightly faster with the tsp tunes compared to the Phearable tunes. The only way I noticed was by driving both back to back.

As far as the defogger issue, the defogger uses the A/C, so it does put more load on the engine, and you’ll notice that your shift points will be slightly different as a result. It’s normal for all tiny engine cars.

Edit: For reference, I have the type r retrofit and exedy clutch. Only other mod is a street MAF PRL CAI and flex fuel kit, so I don’t know how much full bolt-ons and a race maf will affect those issues.

 

[borcth]

Hey, thanks for that detailed reply. I do have a 2020. I had some time to marinate on it and pay attention to when I drive. So, I do notice and I've totally forgotten, that since the new tune, the jerkiness downlow is all gone. I used to have to really feather the clutch and throttle to get it smooth, otherwise i'd be getting whiplash. So that's a plus.

It's interesting, even though I have the rev-blip during a shift, it drops down very fast. Probably because of the RV6 Retrofit Type R SMF. With classic rev hang on stock tune, it would blip high and just sit their and go down like molasses in a cold winter day. So slow and drove me nuts. Here, the revs blip up, but drop quick and still allow me to shift quick. I don't drive hard or bang gears fast, so It's not too intrusive.

The other positive thing is that when it does the rev-blip/rev-hang it burbles. Which I do love the burbly burbles.

Thanks for clarifying the A/C pulling power and effecting the shift points. Makes sense. Just wanted to make sure it was normal and ok.

I do have another question though. Even though rev-hang has been enabled in the tune, doesn't the Main switch turn that off anyway? Or no matter what, even hitting it, won't do anything. Because when I do hit it, it feels the same. So I'd have to go into tune, uncheck or check the rev hang disable option and now I can manually switch it on the fly? That's how it worked with the Street tune from what I remember.

You mention, throttle. I believe Phearable has it set to Medium padding right? I notice that when I rev-match sometimes the throttle isn't super responsive. Particularly when coming down from 5th to 4th gear. I have to give it a good tap, which sometimes makes me over rev a little. Not super detrimental, just more of a curiosity and I've learned to mitigate it mostly. Though, I'd rather over rev, then under rev when down shifting. Is that have to do with throttle padding?


Thanks again.

 

[Chaucer]

No problem. There isn’t all that much written about the 2020 quirks so I’m glad to contribute what I can.

That’s correct, you’ll need to check the disable rev hang box in the tune itself for the main button to make a difference.

For me, the lighter flywheel made enough of a difference that having it enabled to remove the 2020 jerkiness doesn’t annoy me anymore.

Throttle padding only comes into play when rev hang is disabled via the tune and the main button is off. It’s essentially in there to help folks new to driving stick. It prevents the revs from falling as quickly as they potentially can. When rev hang is still enabled, that setting doesn’t affect anything.

The throttle responsiveness setting is what makes the difference when bilping the throttle during a downshift, with a caveat. The throttle mapping in the 1.5R tune is noticeably different in 5th and 6th compared to 2nd-4th. That can make the 5th to 4th blip feel different than the 4th to 3rd or 3rd to 2nd.

I believe this is to prevent people from using full boost by mistake in those gears, since it takes more pedal travel to achieve it than the lower gears. It’s a nice inclusion, but imo it’s better to just set a boost limit in 5th and 6th to ensure you don’t run into that issue.

 

[borcth]

Okay very good. Thanks again. Right now I'm giving the current setup a chance to work it self out. Good to know I can reflash at some point if I decide I want the rev hang disable button option back. With the lighter flywheel it does make massive difference in how quick it drops even with rev hang apparently still enabled.


So far I'm getting used to it and can see where it has its benefits. Especially at slower speeds. Less jerky. I'm still able to shift pretty quick and not have the awful rev hang feel from stock and having to wait for rpms to drop.

I don't bang gears but sometimes I gotta get up and go before pple run me over. Esp from a light. Pple drive like lunatics these days and just wanna mash their pedal to get to the next light.

Anyway, very cool and thanks again. If something comes up in the future I'll repost again in this thread.

 

[borcth]

Update:

I reflashed and disabled it. I couldn't stand it anymore. Gave it 2 months. The moment I reflashed and pulled out, I already felt the positive difference. It felt raw and like how it should. Way less floaty and no RPM blips every time I shifted which made me sound like I didn't know how to drive a manual. Less burbles now though, but IDC, I just wanted to have fun driving again. Driving with the rev hang for just 2 months had already changed the way I drive. Made me slower and lazier. With the RV6 retrofit flywheel and clutch and NO rev hang, the RPMs drop so freaking fast now. I love it.

I never or at least hardly notice any issues between shifts or low speed driving. I had been driving with rev hang fully disabled, but with the stock flywheel for over a year and learned how to feather the clutch to prevent any sort of bucking. I just got the clutch job done back in September. The RV6 setup just made things better. Car is more engaging now. I also have the 27won Street 70a RMM. A little bit of notchiness, but I've gotten used to that. Probably can be resolved with a heavier shift knob or different clutch fluid other than OEM. It's been notchy since clutch job anyway and is in no way related to the flash or rev hang disabled.

Anyway, yea, I had enough and reflashed it. It's now how it should be and could not be happier.

 

[Chaucer]

Update:

I reflashed and disabled it. I couldn't stand it anymore. Gave it 2 months. The moment I reflashed and pulled out, I already felt the positive difference. It felt raw and like how it should. Way less floaty and no RPM blips every time I shifted which made me sound like I didn't know how to drive a manual. Less burbles now though, but IDC, I just wanted to have fun driving again. Driving with the rev hang for just 2 months had already changed the way I drive. Made me slower and lazier. With the RV6 retrofit flywheel and clutch and NO rev hang, the RPMs drop so freaking fast now. I love it.

I never or at least hardly notice any issues between shifts or low speed driving. I had been driving with rev hang fully disabled, but with the stock flywheel for over a year and learned how to feather the clutch to prevent any sort of bucking. I just got the clutch job done back in September. The RV6 setup just made things better. Car is more engaging now. I also have the 27won Street 70a RMM. A little bit of notchiness, but I've gotten used to that. Probably can be resolved with a heavier shift knob or different clutch fluid other than OEM. It's been notchy since clutch job anyway and is in no way related to the flash or rev hang disabled.

Anyway, yea, I had enough and reflashed it. It's now how it should be and could not be happier.

I’m glad you got it squared for yourself. Makes me a little tempted try disabling rev hang again. From what I remember my main annoyance was when going off and then back on the throttle at highish rpm. Staying in gear for a higher speed turn was a jerk-fest. I might give it another go.

 

[borcth]

I’m glad you got it squared for yourself. Makes me a little tempted try disabling rev hang again. From what I remember my main annoyance was when going off and then back on the throttle at highish rpm. Staying in gear for a higher speed turn was a jerk-fest. I might give it another go.

It's way better now. I've learned to modulate the throttle to where it does not jerk esp in 1st gear driving around the parking lot or pulling out. Unless I'm sloppy and not paying attention. To be honest, I don't rev that high very often or bang gears. 20 years of banging gears off the limiter and destroying clutches and transmissions will do that to ya. Call me old.

Also a RMM helps out a lot. It might help you out if you don't have one yet. I know for me, when I was on the stock clutch and DMF, the car jerked a lot between gears esp in low gear/low speed or high rpm, low gear like you mentioned. RMM took care most of it and the RV6 retro w/SMF fixed the rest. You'll get NVM though from the RMM. So it's a trade off. But I enjoy the raw feel. Connects me to the car.

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