The Forced Induction VR6 thread

[Kevin Bacon 5]

VW.

 

I believe it's a 7DPK 1380 you need, otherwise known as a standard VR6 A/C belt.

[poll250 0]

As I'm replacing the radiator, I thought I might as well replace the coolant hose that goes from the rocker cover to the heater matrix, as it's bound to get a lot of extra heat thrown at it soon. Will also heat wrap it to keep it as cool as possible.

 

Does anyone know of the top of their head whether I should get 18 or 19mm ID hose?. I tried measuring this morning but it's kinda hard to gauge with those still on the car.

 

While I'm at it I guess I'll have to block off the pipes that go to the Throttle body. Is there an accepted way to do this? Screw an 8mm bolt into it?

[coullstar 0]

What clutchs are folk using?

[Kevin Bacon 5]

Helix Autosport

 

Cover -60-4603

Plate - 70-4606

[coullstar 0]

Thanks, non paddle type I see. How long are you getting out of these?

[Kevin Bacon 5]

God no.

 

I took my original Helix out in Sept 09 because of a rattling noise in the gearbox. Clutch had done 40 odd K at that point. The noise was coming from somewhere else, but annoyingly the clutch still had at least another 40-50K in it!!. It had worn-in real nice. No bluespots or scuffs what so ever on the flywheel or pressure plate.

 

So yeah, they last ages is the quick answer :lol:

 

See, this is what I keep going on about. If you keep the power levels sensible you don't need stupid paddle clutches and other assorted things that are pig to drive on the road :D

[coullstar 0]

Yeah Im thinking of changing to a normal one and using the car more. Its the one thing that really annoys me with the car. Will give it a go myself I think once the MOT's done.

[Kevin Bacon 5]

Works nice with the Schimmel 9lb cromoly flywheel :D

 

That's the thing. There's no point in having a VRT if it can't be driven. If mine wasn't daily useable as commuting transport I wouldn't have bothered with it. I really have got my cake and I'm enjoying eating it too :D

[coullstar 0]

Right oh, had the MOT done on Sat. The CO2 levels were a high but the A/F gauge reading seems fine and they were fine on the dyno end of last year. Only thing Ive done since then is add the CAT into the exhaust. Not checked the plugs yet but last time I did they were fine. Any other possible reasons for the high CO2 levels other than rich fuel mixture?

[junkie 0]

All I can think is it's cat related as that's all that's changed or you have a leak maybe on the exhaust before the lambda

[fla 9]

can anyone tell me where i can get the correct belt for my v9f stg 2 set up?

Steve

 

i have a spare, (kept just in case) if required.

On the topic of belts, how would you go about the install keeping aircon in the mix? I'd love a turbo, but by the looks of it a supercharger will be simpler to setup?

[VR6Joni 0]

What's everyone doing with the engine breather setup?

I've noticed mines been a bit smellier with the milder weather, an oil change improved it but I'd like it to be better.

So what's everyone else's experiences?

[chazrad 0]

I've got an oil catch tank fitted which returns oil to the sump via a custom pipe. It vents to atmosphere via a pipe that runs down under the car. I don't appear to get any oil vapours/smells inside the car.

[poll250 0]

Ok my car's been at Stealth for 3 1/2 weeks now so my mind has officially started to wander, so bear with me.

 

I've been reading/thinking a lot about front end grip when FI, I'll have a diff and Traction Control, but would wider tyres also help? I currently run 205s on 7.5J rims, having had a look around it looks like you can fit 235s to 8J rims.

 

I know that a larger contact area will obviously provide more grip, hence the reason RWD cars have such wide tyres, but what effect would 225/235s have on the front? Would they wreck the steering/handling? Has anyone ever tried it?

[boost monkey 0]

you'd be better with high quality performance tyres, than just the widest you can find. It's all about slip angles and the lateral force that can be generated as the tyres deform due to vertical and lateral loads.

[coullstar 0]

With a diff and the Racelogic you wont need to worry about that. Stick with 205's. Even in the wet if I turn the boost down a little I still get decent traction if Im gentle with the throttle and you only need to be gentle to still go quick.

[Kevin Bacon 5]

What's everyone doing with the engine breather setup?

 

If you can smell crankcase gases, you have a leak somewhere, or the fumes aren't escaping under the car and coming back in via the heater fan, or some unblocked grommet holes etc....

 

....but.... http://www.42draftdesigns.com/categories/products/catchcans.html

 

I have the "Stealth Catch can" and it's excellent.

 

Blow-by gases will be worse this time of year due to the oil being thinner. You could try switching to a thicker oil. 10W/60 and 10W/50 synthetics definitely help with this problem on forced induction 12Vs. 10W/40 and thinner just dissapears over summer. Well, it did in my old tired 12V and forged pistoned current one.

[VR6Joni 0]

Its whilst stuck in traffic with the heater fan on when the fumes become noticeable!

A catch can is my favourite option however I'm seriously low on space and not sure I can even fit one under the bonnet. :(

I'm currently assuming that recirculating the crank case fumes back to the charger inlet is a bad idea due to fouling up the compressor wheel/housing and charge cooler. Unless this is acceptable, anyone fancy enlightening me? I'm sure I've seen OEM doing this???

[Kevin Bacon 5]

Yeah, common problem, the fumes aren't leaving the engine compartment and getting drawn into the cabin. You could make up some kind of evacuation pump system using an old EGR pump off a 4Motion / 1.8T, but if you're short on space....

 

Another thing you can do is fit a one way valve into your exhaust (downstream of the cat if you have one fitted) and connect the breather to that. The exhaust pressure leaving the engine sucks the crank fumes out with it. Very neat. Very popular method in the states. I'll try and find some links with pics.

 

The draft designs catch can was initially designed for the MK5 TFSI platform, which has terrible intake oiling problems (and also the Audi RS4 V8 etc), so it does a good job of shifting crud. I fed it into my turbo intake for a while and it didn't oil up then intake or intercooler. Doesn't matter if it does anyway tbh. You should see the state of our 1.8T intercooler, turbo and intake after only 40K miles. I can't be arsed to run carb cleaner through them but the car drives perfect!

[VR6Joni 0]

Another question.

Having bumped into a Renault Sport Megane R26 the other day and only being able to keep up at ~5000rmp + I've decided its turbo time. Not sure he expected me to be stuck to his rear bumper though, :)

So GT30R or GT35R?

I want lower down torque than the charger but at the same time, do not want to break any of my drive train components with relative ease. So what's people's opinions on the 2?

Ideally I'd like to know what rpm people experience spool up and full boost at?

I know both can handle 400bhp with easy but are there any gains such as cooler charge air with the GT35 at this sort of power?

[Kevin Bacon 5]

Well done on the Renault. They are cheeky little things, especially on back roads.

 

GT30 is definitely a gearbox breaker. The 35 brings the bulk of torque in right where you want it, ~ 3500rpm and keeps it there until 7000, so you get a nice power band. It spools fairly quick too, so you'll still be making good torque below 3500. I was seeing 4 psi at 2500rpm with the pedal pinned. Full boost was ~ 12psi, which came in at ~ 3500.

 

I am moving onto the 24V + Borg Warner EFR turbo, so I will be selling my old turbo stuff. Keep an eye on the classifieds, some bargains to appear very soon :)

[VR6Joni 0]

Yeah, I was quite surprised how much it took to keep up the Renault, my brother was also a passenger and couldn't believe how quick they are. If it was standard I'd hate to bump into a tuned one.

 

Anyhow I wasn't expecting to hear that you see 4psi at 2500rpm from a GT35, although you do have the BVH. This is most definitely a big improvement over the Rotrex where 4psi is more like 4000rpm. Even though it does have almost the same size compressor dimensions as th GT35 it's simply held back by the engine speed. From then on the boost does rise exponentially which does make it feel quick but its just not quite as wide a band of torque than I'd really like.

 

Oh and cheers for the heads up on the classifieds.

[Kevin Bacon 5]

The Renault's torque kicks in a lot sooner than yours and the vehicle weight is probably the same too, if not lighter.

 

You need the 3.68 Final drive. In my experience, VR6s are just too slow at

 

Nearly all hot hatches now have 6 close ratio gears and it really keeps their engines in the torque sweet spot.

[chazrad 0]

Joni, I can offer a slightly different opinion to Kev's. I know he's had both types of turbo and I value his judgement but I am finding the GT3071 I have to be absolutely superb. Frankly, I seldom reve the engine out to the top of the rev range anyway, so for me, its all about the low down torque. The performance clearly depends on what boost setting I've got selected, howver, the GT30 produces max torque about 1000rpm lower than the GT35 (somewhere around 3000rpm). I find it just so flexible and responsive to drive, and have yet to find a situation when I'm lacking mid range punch. I'm actually only using setting 2 of 4 at the moment (around 9 psi as opposed to the full fat 16psi) and I'm finding it perfectly punchy enough. I reckon 9 psi must equate to somewhere around 300bhp and 300ftlb. Kev may well be right about the GT30's ability to break gearboxes, but I've never heard of it happening to anyone yet. I thought it was pretty accepted that if you keep torque figures below about 400ftlb, you'll be ok. You may want to consider a gearbox rebuild at the same time as dfoing the engine, so you know its in tip top condition. You might also want to consider a diff whilst you're at it, but then that arguably puts more strain through the 'box by making it much harder to spin away excessive torque.

One final point is that you'll find a roller bearing turbo will spool up just that little bit quicker than a journal bearing turbo, helping to move the torque curve slightly further to the left.

HTH , Charlie.

[jamminvr6storm 0]

I havent been on here for a while!!

 

Just wanted to offer another opinion... I have the GT3076 and I think this gives the best of both worlds, the quick spool of a 30 frame turbo and top end punch similar to that of a 35 frame turbo.

 

To give you an idea, with a big valve head, schimmel cams, stand alone management and a number of other mods my VRT with the 3076 makes 326bhp @ 7psi