vr midrange?

[corradovr6sc 0]

Crank pulley costs 200 dollars and is lighter, so the engine revs faster.

[Kevin Bacon 5]

Whats a Schrick VGI and what does it do, cost, etc?

 

What does the crank pulley do, cost etc?

 

and yes you guessed it, explain the final drive aswell please.

 

unless there is a nice easy search i can do to find a link on all these things??

 

ta

 

IIRC, The Schrick fools the engine into thinking it's got two long 3 cylinder inlet tracts and 1 short 6 input inlet tract. All it is is a version of VW's manifold with a flap in the middle controlled by manifold vacuum. That is, at least, what I ascertained from nosing around a Shrick in Vince's workshop. Neat idea, shame about the cost!

 

Crank pulley. If you look down at the serpentine belt, you'll see a massive pulley which is weighted to absorb conrod harmonics and act as a damper. The idea behind the alloy one is it removes that initial weight the engine has to turn, hitherto speeding it up, giving better throttle response. You can take this theory really far.....alloy flywheel, under driving the alternator etc etc.

There is a difference of opinion on the crank pulley in certain circles, suggesting that removing the iron pulley causes roughness and removes the conrod twisting harmonic absorbtion - ultimately leading to metal fatigue and breakage. Make of that what you will but I'm certainly not risking it for the sake of a few extra ponies.

 

Final drive - this will have the biggest noticable affect. If you want to feel the difference between a low ratio FD and a normal one, drive your car to a Honda dealer and then get in a Civic type R! The acceleration is relentless.....this is due to the stupidly low overall gearing and is how Honda achieve the sub 7 sec 0-60.

By replacing the VR's standard 3.71 (I think) FD with a 3.94 FD, means for every 3.94 turns of the engine, the road wheels complete 1 revolution. So you can immediately picture the affect that is going to have on the acceleration!

 

HTH

 

K

[PhatVR6 0]

I think that's been pretty comprehensively answered.

 

there has not been a sinlge case of anyone reporting any side effects from fitting lightened crank components in a VR6 to my knowledge.

 

the stadard corrado gearbox is 3.66:1 final drive, changing it to the closer 3.94 makes the gears shorter, thus, the engine turns the wheels more easily (effectivley, you get more torque to the wheels as the engine has a greater mechanical advantage). it alos means 4th gear is much more useable. what's the point in being able to got to110mph and still have 2 gears spare? you'll run out of track on most circuits, and if you do it on a road you're just gogint o get banned. 0-100mph is where it's at. mine is geared to do 115@7000rpm in 5th, with an overdrive 0.71:1 6th gear for cruising. as kev says,, acceleration is relentless, it pulls in 4th as well as it used to in 2nd, feels like it has another 50bhp at least.

 

I reccomend gearbox tuning far more than engine tuning. well, just do the gearbox, THEN do the engine :-)

[jedi-knight83 0]

6th gear!!! this sounds like an expensive, complicated mod!

 

I'd love to get the cruising rpm down as 80 - 90 mph revs too high for a V6 IMO.

 

do you have to ghange the gear box completely to get the lower FD and 6th gear? how much is all that?

 

ta

[Joe M 0]

I was looking at the prices of the 6speed when I got my diff and clutch done, just for the gearkit it was about £1500 so I gave it a miss, didnt even bother to ask about labour on that one.

[PhatVR6 0]

My gearbox stands me at around £3000, but it is a vr6 syncro one, with a Gemini 6 smeed kit, custom 6th, 3.94 final drive, Peloquin torque biasing diff, and of course, the all important transfer box for the 4wd, all fully rebuilt with new seals and bearings by stealth racing last year.

 

I've only ran it in 2WD so far, in a mk2 golf (I actually built the car PURELY to try out the gearbox!!). I just can't describe how good it is. I mean, the car had a virtually standard 2.9 VR6 lump in it, but runs 13.75 1/4 miles. For a car with onlty 200BHP that's f*cking quick, and it's all down to the gearbox. I've done 3 trackdays too. Managing a 3rd place at my only my 2nd ever go (at the clubgti national day at Kames) and also managed to set 4th fasted lap at curborough a few months back (see this months The Golf mag).

 

It actually got me thinking that I didn't need 4WD!! the grip available when powering through corners has to be experienced to be believed.

 

Trust me, the VR is not lacking in power, it's lacking in grip, and the gear ratios are just too long (especially when you fit 17" wheels). it's even worse in the golf VR6 with it's 3.3 final drive.

 

It's only a psychological block that stops most peopl spending money on the gearbox. If I said a supercharger kit was £3000 you'd probably say that's cheap? ll becasue it gives you an over inflated power figure to tel your mates down the pub......

 

To quote a well known advertising phrase

 

"power is nothing without control"

[Kevin Bacon 5]

there has not been a sinlge case of anyone reporting any side effects from fitting lightened crank components in a VR6 to my knowledge.

 

No I'm not aware of such a failure either, I think it's just VW erring on the side of caution. I was just doing "the science bit" to try and explain why that particular pulley is so big and heavy. I would have thought a lighter load on the crank would be beneficial rather than detrimental?

 

I actually picked that up from the 12V VR6 vortex forum....there was a stink raised about a thread from an engine geek that was claiming the alloy pulleys cause conrod failure. It was interesting reading, but like you say, unlikely to happen.

 

K

[Kevin Bacon 5]

I mean, the car had a virtually standard 2.9 VR6 lump in it, but runs 13.75 1/4 miles.

 

Interesting.....

 

Found an interesting page today....http://www.classicrsfords.co.u ... ermile.htm

 

PhatVR6 = 14.74 secs

 

I take it that run was without your special gearbox then?

[PhatVR6 0]

That was another car, that was my orange mk2 with a poxy 5 speed 2.8 gearbox, which I blew up!

 

Have a look on York dragways website for my times on the black car, reg #G93 BDC. I'll post up the timing slip if you don't believe me.

[Kevin Bacon 5]

That was another car, that was my orange mk2 with a poxy 5 speed 2.8 gearbox, which I blew up!

 

Have a look on York dragways website for my times on the black car, reg #G93 BDC. I'll post up the timing slip if you don't believe me.

 

I don't disbelieve you, hence asking if that time was with a standard box.......I've been looking into this Final Drive mod again and if you've knocked off a second from your 1/4 mile time, from just gearing, then that tempts me even more!

[PhatVR6 0]

the old time was with the horrid 3.3:1 golf vr gearbox. the 3.6:1 corrado one is ok, but the 3.94 is perfect. even better with the 6 speed!

 

if you'r not planning on forced induction then go for it, it'll make more difference that a £1000's worth of engine mods.

 

Like I keep telling people, the VR doesn't suffer from lack of power. It suffers from lack of low down grunt, throttle response and grip. All of which can be sorted. 200BHP is enough for a FWD car, more than enough if you have an open diff.

[corradovr6sc 0]

How much would someone like Stealth charge for a 3.94 final drive and they rebuild the gearbox at the same time?

[Henny 0]

I'm really thinking hard about changing my gearbox while it's out of the car, so I'd be interested to know how much people are charged for a rebuild + LSD and changing the ratios...

 

Also, Doesn't it screw up the speedo readings badly if you change the final gearing? or is the drive for the speedo AFTER the point that you change it at?

 

The last gearbox I stripped and worked on was for a beetle which has a cable running to the front wheel hub to work the speedo! :roll: :lol:

[Kevin Bacon 5]

Stealth charge about £500 for a full box rebuild....and I can vouch for the top quality workmanship. You get back a box that doens't crunch, at all, and it's very 'snick-snick' through the gears. Sweet :lol:

 

It sounds a lot but gearbox work is quite specialist and you need to preload some of the bearings. For the money you get all new bearings, a bolted diff, new synchro rings and replacement of any fecked gears, which are an unbelieveable £125 each from VW, new flanges if worn and new seals etc....

 

Vince will be happy to modify the box to your requirements whilst it in bits, such as fitting taller 5ths, different FDs etc. He recommends the G60 3.71 diff but you can also go with Phat's 3.94, which comes from a Passat I think.

 

As Henny has pointed out, it might be worth taking the speedo transponder from the donor box (if they're different, I don't know if they are or not) to keep the speedo calibration correct.

 

K

[Henny 0]

Cheers Kev, I think you may have either just saved me some money, or made me spend some... I'm not sure which yet! :roll: :lol:

 

Time for a rebuild I think! LSD, new 1st 2nd and 3rd and a different final drive here I come! :wink: :lol: 8) Wonder how much a 6th would cost... :wink:

[PhatVR6 0]

The speedo drive ring it attached to the outer diff casing. so it spins at the smae speed as the wheels. so, no, you don't need to chage the speedo head.

 

new final drives are £200 from VAG, more if you want a VW Motorsport spec one. an AGC passat box has a 3.94 final drive, but beware, as pre 1990 ones have the early 020 style rivets and the bolt holes are too small for the 02A diff bolt kit (£70). be aware that if you're running a 3.94 and only 15" wheels then yo may need the TDI 5th gear, 0.71 or 0.72 I think otherwise motorway crousing will be a hig revving nightmare. I've got a 0.75:1 6th gear in mine, it's jsut a tiny bit taller than the stick VR6 5th, but I'll be running bigger wheels than standard anyway, which is why I went for reallt short gearing. on 15"s is mentally short! but make SUCH a big difference.

 

All you corrado VR6 owners should go drive a gofl VR6 to see how horrible the longer final drive is fr an idea of the difference this mod makes.

 

Stealth built up my box, and I don't have any bother with it at all.

 

I used Redline MT-90 synthetic oil in it too.

 

Oh, there's a 4.2:1 final drive availabe too if you're feeling a bit mad! :twisted:

[PhatVR6 0]

The 6 speed kit is £1366 +VAT and fitting.

 

that's for a new 3rd-6th gear set. if I were to have it done again I'd pay the extra money for the semi straight 1st and 2nd too becasue I love the touring car style whine that the other gears make.

[Henny 0]

Cool, cheers Phat! I'll have a word with Stealth today about an LSD, rebuild, restack and other options... 8)

[PhatVR6 0]

Mine cost me about £3000 all in.........

[Kevin Bacon 5]

I hereby elect Mr Phat as our resident gearbox expert :lol:

 

Vince is the main man for gearbox builds...he co-developed the Gemini 6 speed kit 8) I don't know what he does to them but the 020 he built for my 16v (with 8V 5th for better motorway cruising) was sublime. There was an audible 'click' when changing gear too, like throwing a light switch...dunno what he did but it was mega slick :lol:

 

I have driven a Golf VR6 and agree about the gearing. It's awful, makes the car feel really sluggish.

[Henny 0]

Right, after a nice conversation this lunchtime, it looks like I'm taking a drive down to Stealth in the morning with my gearbox... 8)

 

Complete rebuild, LSD, VR6 1st and second and a 3.94 final drive... Just over £1500 all in :D After spending the kinda money I have on the rest of the car, I'd be stupid not to splash this last bit on the box while it's out and is the only bit left that I've not done anything to... 8)

 

It'll also save me the trouble of cleaning up the somewhat filthy gearbox! :wink: :roll: :lol:

[PhatVR6 0]

mint, you will be very pleased with it. :D

[Kevin Bacon 5]

Excellent! £1500 isn't bad actually, especially as that includes a rebuild, new cogs (or from a decent used VR box) and the diff. Sweet :lol:

 

I will be doing the same (LSD and 3.71 or 3.94) when my current box retires.....

 

K

[PhatVR6 0]

It's one of those mods that makes SO much difference but is virtually ignored in the UK.

 

It's more cost effective than engine tuning, doesn't affect your insurance or reliability either!

[Joe M 0]

After having my diff fitted for a month now I dont think id buy another fwd car without making sure I could get one for it first. :D

Best mod that can be done after suspension imo. :twisted:

 

I considered changing the final drive but didnt want the higher reving on motorways or the increased fuel consumption.