...mostly anyway
Thought I'd share my impression on a little mod I have been bombing around with for the last few weeks that seems to have improved my Cupra from a great car with a pretty large and annoying fly in the ointment to a fantastic car and as a real Brucey bonus it only costs about £50 to do.
I do like detail, so this may be a case of TL;DR or teaching your granny
how to suck eggs for some, but for those of you sick of the wheel hop stick with me and I'll explain it as best I can, for the rest who don't want the waffling, skip to the TL;DR bit
Anyone who has driven a Cupra with a bit of gusto will probably have experienced the two scenarios:
1) You give it a bit of beans from a standstill and you get a handful of annoying wheel hops which sound like the car has fallen off a set of jack stands about 5 times in rapid succession
2) You are driving around giving it the beans when you hit a relatively small imperfection in the road (roundabouts were my favourite) and you get that falling off the stands noise again
Neither of these events were something that I was happy with in my new car so I did a little digging into wheel hop and the MQB platform.
If you really want to know the nerdy science I found this article quite helpful
http://www.mc2racing.com/tech/20061012a/
Long story short after a bit of digging on mainly the USA based forums for the Golf GTI Mk7 the common consensus was the weak link was the Torque Arm or Lower Engine Mount, specifically the bushing. This part prevents the engine from rocking back and forth too much while under power by use of an arm attached to the engine, it also dampens some of the vibrations from the engine.
This arm is bolted to the cross-member using a bushing... a bushing which, as far as I can discern, is shared across the MQB platform... yep the shame rubber bushing that stops a 1.4TSI 138bhp lump from rocking back and forth under its own steam is doing the same job for the 2.0TSI 276bhp lump. While I get the whole "shared platform to keep costs down" thing, I would have thought it would be wise to beef up certain areas of a car for higher output models, certainly seen as this is only one of three mounts bolting the powerplant to the chassis.
Now the fix, basically, is to stiffen this bushing up so it can't flex too much, however stiffen it up too much and you will feel every vibration through the engine.
There are a number of retailers that already sell fixes in various guises for this issue, one is the "VWR Uprated Lower Engine Mount and Torque Link", a pretty fearsome looking bit of kit, however for me it looks like it would be too stiff (makes Kenneth Williams noises), it requires a lot of work to get it fitted and it isn't cheap. The expense bit isn't really the issue but my car spends most of its time on the motorway and I don't fancy having my eyes vibrated out while travelling up the M5, also if there is an issue with the car and I need to take it to SEAT, I'd like to be able to remove the mod, for obvious reasons, in half an hour as opposed to half a day.
Answer? Torque Arm insert.
It is basically a moulded piece of Polyurethane that fits inside the gaps of the stock bushing, it will firm up the bushing making the car less prone to wheel hop but is easy to install and remove.
Two companies make these, Neuspeed and Black Forest Industries. BFI do two compounds, street and track, Neuspeed do one street compound. I picked Neuspeed as it was easily available in the UK and looked like a better design.
Both items fit in pretty much the same way, you remove the bolt running through the stock bushing, pop the insert in and bolt it back together using a specially designed washer. In BFI’s case you also use their own supplied bolt.
Just incase you were wondering, here are the fitting instructions for the two:
www.neuspeed.com/media/attachments/345_22.10.92.pdf
http://blackforestindustries.com/FSitems/MQB_Torque_Arm_Insert_Instructions.pdf
TL;DR
Hi again! I fitted the Neuspeed Torque Arm Insert a couple of weeks ago and I have been impressed, it cost £55 from a VWG Specialist and required 30 minutes of my time to fit.
I would say 80-90% of the wheel hop has been eliminated, it is harder to provoke and when it does hop, it does it for less than half the time it did before and it is nowhere near as vicious. It now feels as if it has gone over a small bump at about 30mph as opposed to falling off a cliff.
Personally I have not noticed a huge difference in shifting as I have a DSG car, but it does feel a little more immediate when I nail it and a little less “rubbery” when accelerating, not a huge difference I’ll admit.
The insert does transmit a small amount of vibration into the car, depending on your viewpoint it can be either a good thing or a bad thing, for me I like it. The car seems a little more vocal and communicative and less clinical now as you can feel what the engine is doing a bit more, it’s nothing offensive just a little fizz you can feel as a driver. It also seems to produce a nice roar in the cabin when you’re having fun, but it doesn’t sound fake like the Soundaktor nor is it intrusive.
Some of the USA forums have reported annoying vibrations in various situations such as idling, A/C on etc, there are only two times I really notice it.
First is starting the engine, it has a bit more of a kick to it but it lasts a fraction of a second, it could be annoying if you use start/stop 20x a day and/or are really sensitive but I am not bothered by it.
Second is reverse and I’ll be brutally honest here if it vibrated while idling, moving, or with the A/C on like it does in reverse, I would remove the insert. It only feels vibey in reverse with no brake applied (again DSG car), it isn’t shaking your eyes out but if it happened while going forward it would quickly become tedious, my thinking however is how much time do you spend in reverse? For the amount of wheel hop it has quashed it is a pretty small sacrifice.
At some point I will probably try the BFI Track Insert but I suspect that would be too harsh for a daily driver.
For anyone who has stuck through to the end of my essay, I hope this helps and it will be released in Paperback come the New Year