Forced Induction Questions

[VR6Pete 1,455]

I'm thinking of once I'ev got my ABS/Air Con sorted etc... of going down the forced induction route. a couple of newbiee questions here...

1) What's generally more reliable, Turbo or Super Charger?

2) I haven't seen any VR's with a Schrick and a Turbo before, can it be done?

3) What else do I need to do to the engine to go down either route?

4) Expected cost and power out puts for both?

Thanks in advance.

Pete

[Guest Olly_K]

1) i would say turbo

2) not that im aware of, something to do with the amount of compressed air going through ?

3) Not entirely sure, i would speak to dubsport or designa dubs

4) smallish turbo 300+, s/c 250+

IMO !

[Eat this 2]

pete if u blow it up il buy it off u lol and id def check the insurance 1st ur payin £2.5k now x) :@

[ Edited Wed Jun 23 2004, 08:21AM ]

[eViL 0]

Turbo more reliable?

I don't ever remember seeing a melted Supercharger anywhere.. I can show you hundreds of f00ked turbos though..

[VRmonster 1]

im in this boat at the moment, and thought about the charger, but the decing point was. the ptshhhh wins over the reliability. ha ha.

the standard vr6 block can handle 300bhp, and possably 350 on a regular basis. but ive been advised if i go more than 10 psi i will have to uprate things like headbolts, pistons, conrods. and lower the compression.

so if you take a look around at some of the kits, most of them quote 350 bhp with lowered compression ratio and uprated headbolts. seems like a reliable option. designadubs have just designed a turbo kit, but looking at it its pretty scruffy, so id think about importing one and having it fitted. heres some links that mite interest you. im going with the first kit btw. looks very nice.

http://www.kineticmotorsport.com/projects/kineticvr6tkit.html

http://www.vwturbo.com/products/items/mk3vr6.asp

http://www.eiptuning.com/eip/vwa2a3stage1vr6turbo.html

http://www.designadubs.com/vr6turbo.html

http://swankhouse.com/

[ Edited Wed Jun 23 2004, 04:39PM ]

[ Edited Wed Jun 23 2004, 04:41PM ]

[gazbrook 0]

you can put a dump valve on a charger so that shouldn't sway your decision for a turbo, yes you can before you say otherwise, Andy at Awesome told me you can do it and other reliable sources have told me the same. Eip and Dubsport say that turbos have come on so much that they are as reliable as chargers, I don't believe that 100% though as salesmen will tell you anything.Its £5800 inc vat for a stage2 turbo ,360 bhp and similar torque at dubsport or £3700 inc vat for a stage 2 charger 280 bhp and approx 250 torque at Nik Saran.(cheaper than their website says!!) A charger can be fit in the day a turbo is a matter of weeks for Dubsport, or even months from what I have heard about them. You will want either a decent lsd,traction control or a 4wd conversion(if you are a lotto winner) to put that power safely to the road imo.I also think uprated brakes and driveshaft would be a good idea.

[FishWick 21]

My advice, coming from a Turbo'd MK2 16V background is to first off sit down and work out what it is you want to achieve. A mega boosted Turbo engine will be useless as a daily driver and Nova GTE's will embarrass you as you wait for the turbine to spool up. The VR is a good basis for forced induction because it can absorb a lot of boost and the big capacity with a Schrick will look after you in the bottom end. One word of caution with the Schrick and FI though, that flap. On rare occasions, the flap has been known to be overwhelmed by the boost pressure and break. Just a wee warning.

And it goes without saying you need to look at the car as a whole, not just the engine, so you'll be wanting to make sure it stops quicker, handles the power on the chassis front and making sure the drivetrain can cope with the extra torque.

There are many products out there to address these issues and the golden rule of tuning is "One mod necessitates another", so you need to have a large budget to hand. You are making the car do things VW never intended it to do, so to make is safe and usable, look at the bigger picture.

Lecture over :-)

[Eat this 2]

ie ask mina his is proper sorted

[FishWick 21]

Yep, because he suscribes to my way of doing things ;-)

[VR6Pete 1,455]

I want to keep the schrick, so a turbo is out of the question, supercharge route i think!

[mightyvr6 0]

i think the flap can take it since it's wide open on full boost but some have put loctite on the nuts to stop them coming loose.

[eViL 0]

You just adjust the flap change to lower revs so it's open earlier, allowing the boost through.

Not Rocket Science boys..

[mightyvr6 0]

at 3500-4000 it's not producing much boost anyway, so there's little stress on the flap.

[eViL 0]

Stealth recommend changing the flap down from 4000 to 3500 to be safe.

And who are we to argue?

[simey 0]

I'd go the supercharged route as turbo's will involve alot more work, i.e. pistons, head work, brakes, chassis etc...

They always say 250 bhp max in a front wheel drive car so 4wd for 360 bhp.

At the end of the day it all depends on what you want to achieve.

[simey 0]

VR6Pete, speak to Vince at Stealth.

[VRmonster 1]

the thing is, altho expensive, turbo is very rare. everyone with a vr6 has thought about s/c. but turbo is for the refined people out there who want a different class of FI. no offence to the s/c people, its just a little bit dated. only my opinion tho, ive never realy liked chargers anyway. it is the easier/quicker/more reliable option tho.

edit: quicker as in quicker turnaround for installation.

[ Edited Fri Jun 25 2004, 02:19PM ]

[mina 0]

VR Monster is right - s/chargers are bloody noisy!! Mine sounds so smooth and refined without it. You can get a big power increase with a turbo, but the power delivery will not be as smooth - check out some rolling road plots and see what a mean. However, as they generate more boost lower down and they consequently give more torque lower down.

You pays your money.....and you takes your choice!!!

Mina

[simey 0]

This is why I went down s/c route as a turbo for sure would blow the auto box....

[VRmonster 1]

i dont mind the noise, its just the concept. i prefer the lag you see with a turbo, gives me a bit of a giggle. lol. the supercharger seems too smooth for my liking. i drove a friends g40 before he sold it, (wish id have bought it now. lol) and it didnt feel as thou it had any more power than my 1.2 nova, till you realised youd hit a tonne in very few seconds. lol. still a nice mod tho. if i decide against the turbo, i will deffo go charger. cos FI VR6's rock!!!

with your car being british style engineered mina, how much maintainence does she take to keep her running sweet? and is it your daily driver/commuter? or just a fun only car like mine?

[ Edited Sat Jun 26 2004, 12:27AM ]

[mina 0]

The car is perfectly usable day-to-day. It idles normally, never overheats and is fine in traffic. You just need to change the oil every 3 months - I used to change it twice a year on my previous NA VR so that's no hardship.

It drives just like a standard VR - the clutch is slightly heavier, but the gearbox is still light in action.

The only problem is if something big ever went then it would cost ££££s! Head gasket went last year - cost £180 for a copper replacement from Vince plus labour to fit! But as long as you are sensible and don't drive it like a tw@t then it's plenty tough enough! As I've got uprated brakes, suspension and gearbox - there's no real weakpoint.

Ask Jules for his opinion - he's had a go!

Cheers

Mina

[VRmonster 1]

Cool. thats settled me a little, i was expecting you to have to rebuild the engine every so often, lol. what you done to your box like, ive been wondering about the best wat to streangthen once Turbo'd. Obviously a quaife lsd is in order and a better clutch, but what else is there that can be done.

[Eat this 2]

mina has a 6 speed box and what about a torque biasin diff arnt they the daddies?

[VRmonster 1]

yeah, thats what i meant, was just in a rush, lol. ma car was nackered and needed towing. lol.

[FishWick 21]

Quaiffes are a good move with FI and a standard car. But rather than letting the excess torque spin away safely, the load is transferred back into the box, so you need to make sure the box can handle it. A standard rebuild with new bearings, synchro cones and a bolted diff will definitely add a little extra strength but if you plan on really big torque, then a stronger gearset, such as the Gemini 6 speed conversion and steel CV cages is a wise move.

The 02A box is quite strong and can cope with a fair amount of torque, but it will be the weakest link if you're putting over 300 pounds of torque through it, especially with an LSD.