Black magic Mk5 GTI track car

[the bruce]

Question is, why you have these issues? Is it the gearbox itself or just the parts between shifter
and gearbox?
The latter ones are easily to replace and there are also some uprated parts like solid bushings.

BTW, there are also Eos FWD gearboxes for the VR6 with much shorter gear ratios. Unfortunately
these have a different casing due to the different mounting angle of the 3.2 VR6. The gear parts
should fit though.

[fuscobal]

I have the solid bushings wich made shifting more precise (les wooblier than before) but still hard to get in a gear fast. Removed the flow restrictor, installed the USP stainless clutch line (not only this one didn't bring any benefit but the rubber gasket broke and my pedal went to the floor on my way to Hungaroring, one day before the other event that almost destroyed the engine), replaced the clutch bearing, went through 2 sets of Sachs racing clutches (changed the first under warranty for exactly the same reason). While my car was under engine repairing, I've also installed a spacer in the gearbox, where the input shaft sits but I'm yet to see if it cured the problem !

[the bruce]

 

Seems it's the gearbox or you're an extremely quick shifting guy. 

I "only" had 4th gear issues now and then when the car has been new. These went
with time. I have to admit I'm not fastest shifting man, too.
Remember you don't loose that much (lap) time. The car still moves when you kick the
clutch. It just decerates 1 or 2 km/h when you accelerate. It even does nothing when
downshifting while braking.

[fuscobal]

Don't need for fast downshifting, you have plenty of time there but I'd certainly like faster changes on acceleration areas. I'd say it mattrs pretty much. On the Hungaroring straight (700m) while going side by side with a 911 Carrera 4S I was pulling on him during acceleration but loosing some of the advantage during the 2 gearchanges (3 to 4 and then 5). I'd say I was loosing about 5-7m only there. Probably on the entire track it would be like 20-25m wich at a medium speed of 30-35m/s would mean close to 1 sec ! However, I will stop talkin about gearchanges until I solve my cooling problems first    What do you say about this plan :

1) Sell the S3 FMIC and Forge Twintercooler and replace them with a single one in the stock location (Wagner, THS...). What do you know to be the best here and will it have the same performance as the 2 I have know ?
2) Install the OEM water radiator in the OEM location
3) Install the INA Engineering Mocal oil cooler where the Twintercooler was (it's much smaller than the twintercooler so I guess it shouldn't block the airflow to the radiators too much)

[fuscobal]

Decided to drill 2 holes on the legs for the 3 existing ones on the droptabs. Thus, I will have 6 settings instead of 3. The plastic add-on that comes with the GTI and was removed to fix the aluminium legs had 2.2kg !!! . The wings has 0.95kg and the legs about 0.3kg each. It so seems the wing+legs will have about 1.6kg wich is less than what I had before...sounds pretty good to me :)


PS : Legs are now ready for painting along with the trunk lid...in about 1 week we should be able to see the final result !

[fuscobal]

Thanks, will have to take outsome of the plastic trims inside though (pillars and roof). Will also add a roll cage and belts when possible !

[fuscobal]

Finally done with the wing. All in all the new wing + monts + steel reinforcing of the trunk lid has about the same weight as the OEM plastic add-on to the trunk lid. The setting on the pics below has about 12-14 AOA (relative to the air direction wich already makes about 3.7deg to the horisontal plane). This is about the max downforce setting with this wing. Any more than this and stall occurs. Relative to the end of the lid it is installed 15-16cm away on the horisontal axis in the middle, 18-20cm on the horisontal axis on the sides and 9cm away on the vertical axis.






Uploaded with ImageShack.us




Uploaded with ImageShack.us




Uploaded with ImageShack.us




Uploaded with ImageShack.us




Uploaded with ImageShack.us

[fuscobal]

Uploaded with ImageShack.us




Uploaded with ImageShack.us




Uploaded with ImageShack.us




Uploaded with ImageShack.us




Uploaded with ImageShack.us




Uploaded with ImageShack.us

[the bruce]

Thanks for sharing this !!  

 

This wing may even work better than most of pro racing cars that are limited in their
position by regulations.

The setting on the pics below has about 12-14 AOA (relative to the air direction wich
already makes about 3.7deg to the horisontal plane). This is about the max downforce
setting with this wing. Any more than this and stall occurs.

Max possible angle of attack is hard to plan out in advance. There are some options
for testing you will have read from. Wool strings on the wing, oil or shower gel traces,
zip ties on the rear struts and so on. Poor man's wind channel procedure.

 


ps:
Did you disable the ''thank you'' button?  


pps:
Hope it's ok for you, I posted the pictures here: 

http://www.golfmkv.com/forums/showthread.php?p=3540639#post3540639

[danishmkvgti]

Great looking wing, Fuscobal, we'll have to wait in anticipation on your review after the first track days 

[fuscobal]

It's very good you posted the pics there Bruce, I would have done it anyway today (was very tired and went to sleep yesterday). Didn't do anything with the "thank you" button 

As for the next Hring track day that's on 30th of mars I don't know if the car will be ready. The radiator will arrive tomorrow and will install it in no time but I really want to sort out that idle and besides another problem appeared at my first WOT since I redone the engine and that's the clutch slipped wich is really strange as this clutch should be very powerful and has only like 2000 miles driven hard on it. I hope it's just disc contamination and will open the gearbox to check it !

[fuscobal]

Some measurements made today :

- Forge twintercooler > 5.2kg for the core and about 1kg for each of the 2 hoses (7.2kg all together)
- THS > 11.9kg for the core and about 0.5kg for each of the 2 hoses (12.9kg all together)
- S3 FMIC > 7.6kg (S3+Forge = 14.8kg)
- Hot climate radiator + plastic guide > 1.1kg (about 2 to 2.5kg with all the extra hoses needed for the install)
- Air-con compressor + hose > 6.3kg
- Air-con radiator > 3.1kg
- Other air-con hoses + fluids > aprox. 3kg

All in all I'm cutting about 12.5kg by letting go the air-con system and also gain (hopefully) better cooling for the main water radiator and the intercooler. As for the radiators/intercoolers, by replacing the S3+Forge with THS I will gain about 2kg wich I will then lose again with the install of the hot weather water radiator ! However, had to do it because the aditional water radiators sits very tight against the twintercooler's hose wich can cause problems under high vibrations on the track !

[danishmkvgti]

Some measurements made today :

- Forge twintercooler > 5.2kg for the core and about 1kg for each of the 2 hoses (7.2kg all together)
- THS > 11.9kg for the core and about 0.5kg for each of the 2 hoses (12.9kg all together)
- S3 FMIC > 7.6kg (S3+Forge = 14.8kg)
- Hot climate radiator + plastic guide > 1.1kg (about 2 to 2.5kg with all the extra hoses needed for the install)
- Air-con compressor + hose > 6.3kg
- Air-con radiator > 3.1kg
- Other air-con hoses + fluids > aprox. 3kg

All in all I'm cutting about 12.5kg by letting go the air-con system and also gain (hopefully) better cooling for the main water radiator and the intercooler. As for the radiators/intercoolers, by replacing the S3+Forge with THS I will gain about 2kg wich I will then lose again with the install of the hot weather water radiator ! However, had to do it because the aditional water radiators sits very tight against the twintercooler's hose wich can cause problems under high vibrations on the track !

I'm very pleased with the THS IC currently fitted to my car, and would rate it above the S3+Forge TC solution 

[fuscobal]

Just came back from my mechanic and the car is 99% ready. Filled the coolant tank with water for the moment and started the engine wich seems to work well this time (no more oscillations for now). Installed the THS cooler with a custom pipe between the turbo and the THS and also the additional hot weather radiator. Since we were missing some clamps I couldn't take the car out ! Tomorrow we will have the clamps, mount the front bumper and CAI and that's it. I've also replaced the flexible joint of the Milltek downpipe wich was leaking and we made a straight stainless connector between the upper water hoses to replace the plastic T wich was no longer needed ! Tomorrow everything will be done and there is no need for burn in cause we didn't touch the engine block this time. However, only after some logs and gearbox monitoring I will be able to say if the car will go to the next Hungaroring wich is next saturday !

PS : Seems I didn't mention it but I've entirely replaced the cylinder head with one that had low mileage and wasn't machined like mine (the machining on mine was of low quality so the valves didn't seal well on the seats wich might also have caused those idle oscillations)



Uploaded with ImageShack.us



Uploaded with ImageShack.us



Uploaded with ImageShack.us



Uploaded with ImageShack.us



Uploaded with ImageShack.us



Uploaded with ImageShack.us



Uploaded with ImageShack.us

[the bruce]

Hope the engine is reliable and running fine.