Formentor VZ 310 Stage 2 - Drag racing issues

Mar 22, 2023
Hi everyone, this is my current setup 509 HP / 443 WHP / 480 lb :

- Downpipe 3.5"
- Intake APR
- Brisk Racing spark plugs
- Snow Performance meth kit
- CTS Turbo Intercooler
- Repro Stage 2

I have been having random issues on the drag strip, the power randomly dies, I haven't been able to figure out what's happening and I'm waiting for an OBDEleven to arrive and try to do some live data logging, unfortunately, the dyno and the shop were it was build is like 2,500 km away, and it was running fine over there ( I tested it ).

I'm not sure how to explain it, sometimes it feels like it struggles to switch gears, I know I need to upgrade the DQ381 clutch, but I think that's too soon the car was modded like 3 weeks ago. And sometimes it goes thru gears fine but dies on the top end. My tuner believes it's either the clutch slipping, or the mixture I used to run was too poor.

I used Renegade PRO E85 with pump gas, and he uses a mixture of 100% Ethanol with pump gas. Both mixes were 3lt ethanol per half a tank of 91 octane pump gas

I'm leaving a few videos that are hard to hear due to the other cars' noise but if you listen carefully you can hear the car failing, and even the front dropping due to loss of power

Oh btw launch control is useless now due to the increase of power and torque, front wheels just spin like crazy ( Toyo Proxes R888R ), now I need a haldex controller lol

Run #1 car ran fine ->

Run #2 had to repeat run #1 about 5 mins after due to a failure on the drag strip (sucks) but the car ran fine ->

Run #3 failure at 0:32 and 0:35 then I just let go of the gas ->

Run #4 Just a test right after the failure above, the car ran greater than ever ->

Run #5 failure at 0:34 launch control did not want to engage, so I was very late on the light and did not build enough boost, this has also been happening sometimes, not enough boost on LC and the car just bogs when going into 2nd gear ->

Run #6 car ran fine:

Run #7 failure at 0:50-51ish and 0:52->

All runs were done on Cupra mode, ESC OFF, and DSG set to Manual (Always ran it this way even when it was stock)

I'm sorry if this is not the right thread to post this, hopefully, someone has an idea of what I can check to start figuring this out. Thanks!
Apr 20, 2023
Not sure how accurate your data log is, but after looking at it, doesn't reflect a stage 2 car and your boost is a little low for a stage 2, more like a stage 1+ ,
as for the gear shifts issues your gonna need a proper TCU tune. The TCU tune will help with the Launch and the clutch slip feeling. The TCU stock program is very conservative. Might want to find TVS for a TCU tune.
SEATCUPRA.NET Forum merchandise