I grew up in an Alfa family. Mom drove a Spider, Dad drove a Berlina, Mom raced Spider prepped to DP and Dad raced a GTV in GT4. The Berlina was handed down to me to drive in HS. That GTA is one of the most beautiful cars in the world. I was so disappointed when the joint Mazda/Alfa project ended up being the 124. I really wanted an Alfa.
7
Street Touring Hatchback (STH) discussion/setup
- Thread starter xXDavidCXx
- Start date
I grew up in an Alfa family. Mom drove a Spider, Dad drove a Berlina, Mom raced Spider prepped to DP and Dad raced a GTV in GT4. The Berlina was handed down to me to drive in HS. That GTA is one of the most beautiful cars in the world. I was so disappointed when the joint Mazda/Alfa project ended up being the 124. I really wanted an Alfa.
Mini7
Autocross Champion
- Location
- Charlotte, NC
- Car(s)
- 2017 GTi Sport PP
The 3.0 GTV had one of the best sounding V6’s. I grew up in a large Italian community so Guilias and GT Juniors were common place
When I was young I almost bought a 3.0l Milano (75 on the other side of the world). I ended up in a GTI instead.
JackRabbitSLIM
Go Kart Champion
- Location
- OHIO
- Car(s)
- MK7 GTI
Looks like everything went through for STH in 2021.
https://www.scca.com/pages/fastrack-news
https://www.scca.com/pages/fastrack-news
Stg 2 protune, new clutch, and some 255 RT660's for the front should really pick up the pace next year.
MonkeyMD
Autocross Champion
But you still can't add lsd in sth for awd
Stoked, happy to get the cluch allowance for manuals. It looks like only pressure plate and disc can be changed (so no SMF) which might irk some people, but I'll take what I can get. I was planning to run the sachs kit with the DMF anyways. Long list of parts for black friday...
MonkeyMD
Autocross Champion
Will anyone really know if you have a SMF vs DMF? Not like it's a performance advantage.
Locally, no one will care. If a national event, likely they will notice the chatter.
JackRabbitSLIM
Go Kart Champion
- Location
- OHIO
- Car(s)
- MK7 GTI
I've been looking into the diff stuff and am wondering about the interaction between the VAQ and an aftermarket mechanical one, like the wavetrac.
I came across a couple articles that claim the VAQ can't really handle all the torque that the engine can apply, therefore there will be some amount of slip allowed at the inside.
VW vortex article
Drivetribe article
I'm not sure I buy this whole gear ratio thing. If it were true it seems to me that dyno numbers at the wheels would be higher than at the crank. But just for fun, here are the STH numbers given those assumptions. (gear ratios)
APR stage 1 high torque gives 350 ftlbs at the crank.
MT: 2nd gear * final drive = 2.08 * 3.24 = 6.74 --> 350 ftlbs * 6.74 = 2358 ftlbs at the diff
DSG: 2nd gear * final drive = 1.79 * 4.77 = 8.54 --> 350 ftlbs * 8.54 = 2988 ftlbs at the diff
The articles claim the VAQ can handle up to 1180 ftlbs at the diff. There seems to be reference that the VCDS or similar mods can increase the 1180, but can it double for MT? Triple for DSG? I doubt it. This is me arguing that VAQ isn't worth very much, especially for autocross.
But, what if you install a Wavetrac? What happens? My thinking is that the overall maximum lock would still be the maximum the VAQ can handle. It would be two diffs in series. wtf happens??? Adding a Wavetrac would only change the behavior of the car up to the point the VAQ is at maximum lock? Also, what if the VAQ ECU disagrees with what the Wavetrac is doing or can't keep up? Tires would still be slipping?
I have no idea if I'm right. It's interesting to think about though.
I came across a couple articles that claim the VAQ can't really handle all the torque that the engine can apply, therefore there will be some amount of slip allowed at the inside.
VW vortex article
Drivetribe article
I'm not sure I buy this whole gear ratio thing. If it were true it seems to me that dyno numbers at the wheels would be higher than at the crank. But just for fun, here are the STH numbers given those assumptions. (gear ratios)
APR stage 1 high torque gives 350 ftlbs at the crank.
MT: 2nd gear * final drive = 2.08 * 3.24 = 6.74 --> 350 ftlbs * 6.74 = 2358 ftlbs at the diff
DSG: 2nd gear * final drive = 1.79 * 4.77 = 8.54 --> 350 ftlbs * 8.54 = 2988 ftlbs at the diff
The articles claim the VAQ can handle up to 1180 ftlbs at the diff. There seems to be reference that the VCDS or similar mods can increase the 1180, but can it double for MT? Triple for DSG? I doubt it. This is me arguing that VAQ isn't worth very much, especially for autocross.
But, what if you install a Wavetrac? What happens? My thinking is that the overall maximum lock would still be the maximum the VAQ can handle. It would be two diffs in series. wtf happens??? Adding a Wavetrac would only change the behavior of the car up to the point the VAQ is at maximum lock? Also, what if the VAQ ECU disagrees with what the Wavetrac is doing or can't keep up? Tires would still be slipping?
I have no idea if I'm right. It's interesting to think about though.
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I believe you're correct here - that the wavetrac would certainly lock under conditions that the VAQ wouldn't. Since the VAQ happens "downstream" (after) the wavetrac, it would still need to be able to fully lock to take advantage of the wavetrac. If I was reading he VAQ reference material correctly, there's no fully mechanical connection between the transmission diff and the passenger side axle in the VAQ. If the clutches in the VAQ are activated, they'll still only give you 100% lock up to a certain point. The wavetrac won't help that.
I believe you would need to add the wavetrac and remove the VAQ (replace with non-VAQ axle) to get true wavetrac performance, primarily in the 1-3 gear range.
JackRabbitSLIM
Go Kart Champion
- Location
- OHIO
- Car(s)
- MK7 GTI
That's what I'm thinking too, but that wouldn't be legal. But it should be (personal opinion), since the GTI Base doesn't have VAQ. I would imagine that would be a complicated retrofit too as far as control modules and codes go.
JackRabbitSLIM
Go Kart Champion
- Location
- OHIO
- Car(s)
- MK7 GTI
So I asked Lugod (OS Giken employee and multi time national champion) what he thought. He said if the VAQ is reactionary, and from what I can find it is, an aftermarket mechanical LSD isn't going to get you much because the two axels are decoupled until after the wheel starts slipping. There is a video from the shopDAP guy that shows manufacturer material on the VAQ and it all looks reactionary to me. So that combined with the VAQ possibly not being able to do full lock up anyway makes me think it might be a no-go for a Wavetrac if you have VAQ.
xXDavidCXx
Autocross Champion
- Location
- AZ
- Car(s)
- 2017 GTI SE DSG
If the wave track locks the two axles, why would the VAQ do anything if both tires are spinning at the same speed?
Doesn’t the wave track negate any required action of the VAQ?
Doesn’t the wave track negate any required action of the VAQ?