DCT / Dual-Clutch Gearbox on 13b engine ?
12-04-21, 12:05 PM
#102
The Maxx also uses the stock BMW TCU and firmware, which has pressure limitations for reliability and warranty. Which means reduced torque capacity. I believe they can be reflashed with different firmware (E90 M3 GTS?) but unsure if it gets you all the way to maximum like the HTG can.
Word, yeah I kenw about the lack of upgradability but given the power delivery of a rotary vs modern BMWs I'm less inclined to believe its a requirement off the hop.
12-04-21, 01:29 PM
#103
Rotary Freak
Indycar turbos installed....was hoping for a nice bellmouth snout!
12-04-21, 02:00 PM
#104
Yeah. It's fine for an FD. There is one running that tracks all the time. The problem is the gear ratio. Buying haltech, then a transmission controller on top of it is the main downside. Wish haltech or fuel tech would build transmission control into the ecu.
12-05-21, 02:16 PM
#105
Lol, no room. I do have enclosed air filters for each turbo that's ducted to the foglight holes on my front bumper. I have an FC, so no stock cooler pods to worry about. My IATs are phenomenal and I saw a noticeable increase in required fuel after plumbing proper cold air.
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billyboy (12-08-21)
12-05-21, 03:32 PM
#106
Put simply, there are maps that effect "takeup" and a whole host of maps that effect upshifts and downshifts.
Takeup has a main map that is TPS vs RPM and is full of arbitrary numbers that kind of simulate your clutch pedal when leaving from a stop.
There are other maps for takeup like temperature modifiers for when the gear box is cold, multipliers to change the main takeup map by gear (first and reverse are different ratios, can also start in 2nd if you had to).
The shifting tables include things like how long the shift takes, what the clutch pressure should be once the shift is completed. Most of these maps are 3D maps with engine load on Y axis and gear on X, because each gear behaves differently and you want smoother shifts at low load and fast, crisp shifts at higher load.
There are also maps for "prefill" pressure that effect how smoothly the trans completes the shift. Without prefill pressure, you're basically banging the next gear 0-100 as soon as the GCU says go.
If one of these tables is off, the trans can flare RPM between shifts (slipping the clutches), or be harsh and bang the next gear. If not tuned properly, the trans can hit HARD.
I've been playing with the GCU for maybe 2 months and I'm to the point where 1/2 to 3/4 of the shifts are pretty reasonable. I still have some oddball up and downshifts that are harsher than I like.
Today was literally the last driving day of the season (salt is officially on the roads), and I'm getting the throttle blips correct on downshifts. It's super fun and motorsports-sounding.
Here's another video of me banging 2nd-5th on some cold roads. Only on 7psi and roughly 500-550wtq.
Ambient temps were 42F and the R888Rs were pretty well dead cold. Traction isn't great, but it still accelerates while spinning its nuts off.
https://imgur.com/lklpdSF
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estevan62274 (12-05-21)
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mr2peak (03-19-22)
03-19-22, 12:51 PM
#110
Im using the MaxxECU. While they utilize factory parameters, they continue to unlock more and more and update the software freely. But yes, I hope the HTG option gets smoothed out fully as it opens up more transmission options as well as opens up different ecu combinations.
05-24-22, 06:11 PM
#111
Rotary Freak
^^^^Surprised the kit availability hasn't been mentioned in recent days? 
One of the guys down here developed another option for gearbox control to avoid the hassles seen elsewhere....chip shortage seems to have stymied a product launch that was scheduled for this year though. https://www.mectricmse.com/index.php...rol/ptc-detail Probably a tiny market, but with Haltech sold, maybe some possibility of investment in this area as well?
One of the guys down here developed another option for gearbox control to avoid the hassles seen elsewhere....chip shortage seems to have stymied a product launch that was scheduled for this year though. https://www.mectricmse.com/index.php...rol/ptc-detail Probably a tiny market, but with Haltech sold, maybe some possibility of investment in this area as well?
05-28-22, 02:03 PM
#113
Correct. And the nicest DCT gearbox (from F80/82) has gone from $1600 to $4500 in the used market since this all started. Deals can still be had but nothing like it was. Now the cheaper boxes are going up in price too (E92). The main issue is that the cheaper boxes have low gear ratio (1:1 in 7th gear which is equivalent to 4th in the stock FD 5 speed). This is not an issue when upgrading your diff to 8.8 because there are lots of options (3.1). But if sticking with stock diff (3.9 minimum), not great for cruising.
Positive about the older low ratio trans is that the Maxxecu can control it, so you save the expense of having a separate transmission controller. But if you already have a haltech or something on your car, you probably need to buy the HTG transmission controller anyway unless you want to swap engine ECUs.
And the adapter kits themselves are at different price points.
There are lots of costs and combinations one needs to plan out when determining their their conversion.
Positive about the older low ratio trans is that the Maxxecu can control it, so you save the expense of having a separate transmission controller. But if you already have a haltech or something on your car, you probably need to buy the HTG transmission controller anyway unless you want to swap engine ECUs.
And the adapter kits themselves are at different price points.
There are lots of costs and combinations one needs to plan out when determining their their conversion.
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Monkman33 (05-29-22)
05-29-22, 10:25 PM
#115
^^^^Surprised the kit availability hasn't been mentioned in recent days?
One of the guys down here developed another option for gearbox control to avoid the hassles seen elsewhere....chip shortage seems to have stymied a product launch that was scheduled for this year though. https://www.mectricmse.com/index.php...rol/ptc-detail Probably a tiny market, but with Haltech sold, maybe some possibility of investment in this area as well?
One of the guys down here developed another option for gearbox control to avoid the hassles seen elsewhere....chip shortage seems to have stymied a product launch that was scheduled for this year though. https://www.mectricmse.com/index.php...rol/ptc-detail Probably a tiny market, but with Haltech sold, maybe some possibility of investment in this area as well?
05-29-22, 10:32 PM
#116
Correct. And the nicest DCT gearbox (from F80/82) has gone from $1600 to $4500 in the used market since this all started. Deals can still be had but nothing like it was. Now the cheaper boxes are going up in price too (E92). The main issue is that the cheaper boxes have low gear ratio (1:1 in 7th gear which is equivalent to 4th in the stock FD 5 speed). This is not an issue when upgrading your diff to 8.8 because there are lots of options (3.1). But if sticking with stock diff (3.9 minimum), not great for cruising.
Positive about the older low ratio trans is that the Maxxecu can control it, so you save the expense of having a separate transmission controller. But if you already have a haltech or something on your car, you probably need to buy the HTG transmission controller anyway unless you want to swap engine ECUs.
And the adapter kits themselves are at different price points.
There are lots of costs and combinations one needs to plan out when determining their their conversion.
Positive about the older low ratio trans is that the Maxxecu can control it, so you save the expense of having a separate transmission controller. But if you already have a haltech or something on your car, you probably need to buy the HTG transmission controller anyway unless you want to swap engine ECUs.
And the adapter kits themselves are at different price points.
There are lots of costs and combinations one needs to plan out when determining their their conversion.
Another big difference currently between the kits out there is if one has the manual rear iron or an auto rear iron.
Here are the finished kits for the manual rear iron. There are a few options for the shifter plate now: blank, centered (without the park cable), and slightly offset to the right (for those keeping the parking cable). Designed to not even need to cut the plastic ring inside the shift boot.
Kit 1
Kit 2
Starter, comes pre-mounted and assembled.
Labelled Hardware packaging correlating to instructions 1
Labelled Hardware packaging correlating to instructions 2
Centered (without parking cable)
Slightly offset to the right (retains parking cable)
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billyboy (06-01-22)
06-01-22, 03:53 AM
#120
Rotary Freak
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Monkman33 (06-02-22)
06-06-22, 02:00 PM
#124
Just an unsolicited update - I've been driving my DCT swapped FC all spring with no real issues. There are still some shifts that could be tweaked to be smoother. It's not really priority since the car is running and driving, and I don't really want to mess with it since HTG keeps promising they're about to release closed-loop DCT tuning. HTG keeps hinting that they want people to use their "DBW MOD" feature, which intercepts the PPS (rather than ECU seeing the pedal) and outputs their modified PPS to the ECU. I don't particularly like the idea of them modifying the PPS, since it's a redundant safety device. HTG's software isn't nearly as robust or user-friendly IMO either.
I have spent some time dialing in throttle blips and shift cut and turned the boost up around ~600whp. No issues so far and the stock clutches seem to take it just fine. I'm probably close to 550wtq or more.
The car is a blast to drive. It's a ton more planted and traction is improved with the DCT. I don't run it in Auto mode, so it drives more like a clutch-less sequential that doesn't make you deaf lol.
I have spent some time dialing in throttle blips and shift cut and turned the boost up around ~600whp. No issues so far and the stock clutches seem to take it just fine. I'm probably close to 550wtq or more.
The car is a blast to drive. It's a ton more planted and traction is improved with the DCT. I don't run it in Auto mode, so it drives more like a clutch-less sequential that doesn't make you deaf lol.
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06-10-22, 09:21 AM
#125
#garageguybuild
iTrader: (32)
Just started my DCT swap.. I’m using Neal’s kit so far its straight forward.
I picked my F80 before they doubled in price. It’s crazy what they are asking now.
Steve
I picked my F80 before they doubled in price. It’s crazy what they are asking now.
Steve
Last edited by estevan62274; 06-10-22 at 09:27 AM.