Schrick VGI FAQ, strip down pics & parts info

[PhatVR6 0]

Mines in bits, for polishing. Does anyone want to see what it's like inside?

 

Also, I will be making up templates for new gaskets soon, which I will then be making and supplying, along with polished stainless steel bolt sets.

 

I also have a list of part numbers for the individual compents too if anyone is missing any of them? I'll update this post as and when I get the info onto the site rather than dragging it along, so it should make a good Schrick VGI FAQ.

 

If you have any questions about the VGI, then raise then, and I'll post them up.

 

I'm asking the mods to keep this post a sticky and tidy it up as an when it gets useful.

 

UPDATE: sorry for the delay guys. I took some pics last night before I re-assembled it.

I'm now able to offer gasket sets (home made, but they fit better than the schrick ones! and polished bolt sets.

 

Here's how it works. Article based on the original VWMS Pierburg VSR, but the theory and operation is the same as the Schrick.

 

To produce an acceptable product, tuners must nowadays pay close

attention to what they are doing. Top-end performance is no longer the

only requirement. Potential clients are also seeking wider power bands

and high drivability standards. A synergy of utility and enjoyment of

driving. [Americans hear "Fahrvergnuegen."] Only those tuners who

achieve those goals are highly regarded.

 

Limited by the transverse mounting of the engine, there isn't much room

for generous inlet manifolding. In order to achieve a good compromise

between maximum power output, and adequate torque in day to day use, the

inlet manifold runs across the top of the head. This has circumvented

the shortage of space and allowed the use of an oscillating-flow tuned

inlet manifold. Each cylinder has its own inlet tract that is tuned to

such a length as to ensure positive inlet pressure. As engine output is

proportional to the airflow, this scheme means that the VR6 doesn't have

to be ashamed in the face of competitors. The 2.8 litre produces 174 PS

[ DIN hp] and a maximum torque of 240 Nm at 4200 RPM, and the 2.9 litre

engine in the Corrado achieves 245 Nm at the same engine speed. But this

achievement wasn't enough to satisfy the Wolfsburg developers. To

achieve even more torque, lower down in the rev range, the 6 cylinders

were to breathe even more freely. The idea of the variable inlet

manifold [ german "variables Saugrohr" ] was born and developed in

parallel with the now standard version, with assistance from the

Pierburg GmbH in Neuss, a company which has a high reputation with

things relating to mixture control. The VSR [ abbreviated from the

german ] system did not go into, falling victim to the red pens of

accountants shortly before the VR6 started production. That this piece

of motor technology was not condemned to the depths of the Wolfsburg

catacombs, is thanks to the interests of Volkswagen Motorsport, based in

Hannover. This VW company took the VSR and now offers it as an after-

market conversion kit for 2888 Marks. The kit may be fitted to all VR6s

with 2.8 and 2.9 litre engines.

 

Even though the VSR achieves similar aims to those of the switching

inlet manifold of the 2.8 litre V6s from Audi, the operating principle

is different. In the Audi engine, a long, narrow inlet tract achieves

high torque at low revs; 245 Nm at 3000 RPM. The maximum power is

achieved using a short, wide inlet tract, producing 174 PS at 5500 RPM.

For the engine to be fed through the appropriate channels, depending on

engine speed, inlet manifolds are switched using six individual, vacuum

operated flaps at 4000 RPM. In both stages, the technology is based

purely on tuned oscillating-flow inlet manifolds, with the necessary

switching.

 

The VSR in contrast, two diverse technologies are applied. It is

designed so that at low engine speeds, resonance is used to improve

cylinder charging efficiency -- at higher RPM, oscillation- tuned,

individual, broad tracts are used. Switching from one to the other is

achived by a single flap, also vaccuum operated at 4000 RPM. The tuned

inlet tract operates by the low pressure caused between the throttle

valve and the inlet valve, by the suction of the descending piston,

Through inertia of the air in the tract, the airflow tends to keep

moving towards the inlet, even after it's closed, causing a slight

over-pressure when the inlet valve next opens. This ensures high charge

efficiency even during early stages of the induction stroke. Of course,

further during the same stroke, inlet pressure falls followed by a high

pressure but not before the inlet valve closes.

 

In order to achieve optimal control of the oscillation and reflection of

the column of air in the inlet tract, it needs to be closely coordinated

with valve timing, but this is not possible due to variation in engine

speed. Even at mid-range-rpm, the valve opening and the are out of

synch. The second pressure wave arrives much too early before the inlet

valve closes and a backflow reduces fill efficiency. Now to achieve high

torque under these conditions, resonance-fill is utilised. This is done

by closing the connection flap between a small resonance chamber which

is immediately before short inlet tracts above the inlet valves. This

transforms the 6 cylinder ending into effectively two 3 cylinder engines

with uniform firing times, and which do not have overlapping inlet

strokes. Resonance pulses of up to 0.4 bar [approx 6 psi] above

atmospheric are achieved, leading to remarkable fill efficiency and

torque increases.

 

Even though fitting the VSR requires not great skills, it should be

undertaken by a professional with the right tools. For example, fitting

the new EPROM and the new control harness requires dexterity and special

tools. The new chip doesn't alter the previously-programmed behaviour of

the engine management, it only adds an additional control output for the

electrically- controlled, vacuum operated flap. The kit includes

instructions as to complete installion, including connections to the

vaccum circuit and electrical connections.

 

[ photos of chip in engine maganement unit,

VSR inlet manifold being fitted,

and side-by-side VSR with original manifold. ]

 

Further engine modifications are not required, so one is permitted to

anticipate the VSR transformation. A marked improvement in torque at

mid-range is advertised with 255 Nm available at 3600 RPM on the 2.8

litre engine. This corresponds to an 11% increase at that engine speed.

In the 2.9 litre incarnation, 260 Nm is available, providing more

performance in the most-used rev range. There is no promise of more

power in the higher RPM range.

 

To illustrate the performance improvement in a VSR Golf, one doesn't

need any test equipment! Almost right from the start, at below 3000 RPM,

a new urge is sensed. Up to 4000 RPM the engine provides markedly better

acceleration, yet above, the previously expected manners appear because

the torque curve corresponds to that of the standard engine. Even more!

After the impetuous acceleration, the switchover feels almost reserved.

The steeply increasing torque curve up to 3600 RPM also shows a rapid

fall back to the norm between 3600 and 4000 RPM. The torque improvement

is an excellent fit to the Golf VR6.

 

In fourth gear, the torque boost corresponds to 90 to 120 kmh, in fifth

to 110 to 150 kmh. This turns the Golf into a sprinter, that none of the

near-200 PS professionally tuned chariots comes near. Testign showed

that acceleration from 90 to 120 kmh in fourth gear only took 5.4

seconds. The standard VR6 Golf took 6.1 seconds and a near-200 PS

Oettinger VR6 Golf taking 6.4 seconds, and a Wendland special taking 6.2

seconds. No wonder because their maximum torque happens at much higher

RPM.

 

Unremarkably, the VSR trick didn't improve peak acceleration or top

speed, both of these being exclusively in the higher rev range.

 

The VR6 opens up a new field for Volkswagen Motorsport tuning. This is

appropriate when one expects high torque for comfortable and sporty

driving. It's even more attractive because testing showed reduced fuel

consumption by half a litre [ per 100 km ]. On the other hand, the VSR

offers professional tuners an innovative platform for development - as

some of them have already indicated.

 

----------------

[End extract]

 

It's worth pointing out that the VGI DOES actually offer high end gains too, as it out flows the stick manifold, has tuned length runners (unlike the VSR) and works great in conjunction with 268 cams.

[corradovr6sc 0]

Phat, are the gaskets on the schrick reusable? Are you making your replacement gaskets out of metal?

[PhatVR6 0]

the gaskets are paper, made by Elring. My mate lives near an Elring factory, so we will approach them about making replacements, again out of paper.

[kieron 0]

where did you get it polished?

 

for £50 I'm f*cked if I'm spending the next 2 weeks doing the rest of mine.

 

Hi-Pol Metal Finishers

Unit 8 The Boatyard Industrial Estate

Fareham Hampshire

PO16 0TA

 

Tel: 01329 289982

 

They are only a small local outfit but I'd suspect most similar places around the country will charge similar cash.

[PhatVR6 0]

OK, inside the VGI we go.

 

this is what it looks like from the back with the mechnism removed.

 

 

the small hole you see in the middle is where the flap pivots.

 

And here's the mecanhism in place (valve shut)

 

 

the rod goes up into the solenoid valve, which is vacuum operated and lifts upwards when the vacuum is let into it.

 

Here's the flap in it's shut position, below 4000rpm, no vacuum

 

 

Note how it dives the plenum into 2 seperate chambers.

 

And when the vacuum is let into the solenoid, it turns the flat open like this

 

 

giving a full plenum volume

 

These are the runners partially polished

 

 

The bonnet has to be cut away like this to clear

 

 

And this is how it looks on the car

[Kevin Bacon 5]

Other useful info:-

 

Try and source an early rubber inlet hose (92-93 model year) part no - HG0 1H0 129 627E for cars with the later rigid inlet hose. The rigid hose gets stretched too much as it has little 'give', meaning the airbox tilts up. The rubber hose is way better and more durable.

 

Want a neater hose on the flap actuator?

 

Get a 90 degree bend pipe from a MK3 Golf. Part number 893955665 82p+VAT.

The hose won't rub on the bonnet and looks a lot neater.

 

How do I wire up the Schrick?

 

Schrick Red wire to ECU red/blue wire - Pin 23. It's the biggest wire on the plug, so hard to miss.

Schrick Blue wire to ECU Black/green wire - Pin 22.

Schrick Black wire to ground. There is a hidden bolt (plastic cap on it) near the leaf guard, use that.

Schrick white wires to vac solenoid.

 

Vacuum connections.

 

Large vac pot inlet to Servo hose outlet. There are 2 green caps on the servo hose above the gearbox. Pull one off and use that as your vacuum source.

Small vac pot inlet to Vacuum solenoid (lower, input)

Manifold actuator to vacuum solenoid (upper, output)

 

When the manifold upper half is nipped up, check the flap is free moving with a screwdriver, by rotating the cam from above. If it binds, you will need to slacken off the bearings. If it's too loose, they'll need tightening up. Speak to Vince at Stealth about this as there have been quite a few like this, mine included!

 

You can also check the flap is moving OK with the engine running. Get a length of spare hose to reach from the servo hose outlets to the flap. Disconnect the original vac outlet hose and connect your free length to it. Now start the car, it will run a bit rough due to the intentional servo leak, and put the hose onto the flap actuator. It should lift up immediately, if not, it's binding.

 

K

[Fasteddie 0]

:D

[Fasteddie 0]

yes sounds good

[trebor 0]

Can anyone comment on this " If you ceramic coat the underside of the manifold, heat emissive coat the top. Put an air-flow aid coating on the insides. This combined with 268cam intake is good for 220 bhp 40ib/ft torque----

 

The figures sound about right. However havent heard of the ceramic coates etc

:roll:

[dr_mat 0]

The coatings on the outside are supposed to improve the heat transfer (or reduce it, in the case of the underside). The Schrick tends to get pretty hot to the touch during normal operation, and that's not good for your performance stats, feeding baking hot air to the engine. The coating on the insides is moot though, from what I've heard the Schrick has pretty good internal smoothing to aid air flow anyway.

[Slimbo 0]

What's the difference between a VGI and a VSR?

[dr_mat 0]

I'm pretty sure you'll find the answer to this in the search, in fact I know you will, cos I've typed it in more than once myself...!

[Kevin Bacon 5]

Can anyone comment on this " If you ceramic coat the underside of the manifold, heat emissive coat the top. Put an air-flow aid coating on the insides. This combined with 268cam intake is good for 220 bhp 40ib/ft torque----

 

The figures sound about right. However havent heard of the ceramic coates etc

:roll:

 

Sounds like horse manure.... I bet that was on the Vortex? Those guys would ceramic coat their girlfriends given half a chance.....

 

Stealth get that out of VGI/268/mapped VR without the use of coatings.....

[dr_mat 0]

Bit worried about the 40lbft torque though... You'd have to rev it to 28875 rpm to get 220 bhp with only 40 lbft torque!! ;)

[trebor 0]

What's the difference between a VGI and a VSR?

 

Havent a clue.

 

The vw motorsport Item is so old you could put it in corrado and call it a classic. However most people on this site will take the piss, laugh and call you a mind-ness fool...DONT MESS WITH ME ILL HUNT YOU DOWN AND DESTROY YOU ( Sorry quote from the transformers, The Movie.;;;;;;;;;; Knew it would come in handy)

 

Sorry the other is the more common Schrick unit. GREAT IM GETTING ONE OF THOSE (about time too)

 

 

Sorry Ive been hitting the red wine AGAIN :oops:

[trebor 0]

Can anyone comment on this " If you ceramic coat the underside of the manifold, heat emissive coat the top. Put an air-flow aid coating on the insides. This combined with 268cam intake is good for 220 bhp 40ib/ft torque----

 

The figures sound about right. However havent heard of the ceramic coates etc

:roll:

 

Sounds like horse manure.... I bet that was on the Vortex? Those guys would ceramic coat their girlfriends given half a chance.....

 

Stealth get that out of VGI/268/mapped VR without the use of coatings.....

 

 

And there more, COme ear

 

No theres this other other other site http://www.vwfixx.com COOOOl like this site MUCXXH

[Kevin Bacon 5]

The differences between VSR and VGI are:-

 

VGI - tuned length inlets, Yes. VSR - Nope.

VGI - Stock AG ECU controlled (CP ECU won't work), No. VSR - Yes

VGI - Easy plug access, No. VSR - Yes

VGI - Sexy looking, No. VSR - Yes

[adambob 0]

So what's the best option then - VGI or VSR ? or are the differences insignificant ?.....

[Kevin Bacon 5]

They're about the same in terms of performance I think, but the VSR is fit and forget. The VGI has to come off every 10 to 15K to change the plugs.

The VSR is no longer available anyway, so it's VGI or nowt unless you can find a VSR on ebay or somewhere...

[adambob 0]

Kevhaywire - any idea why my VR6 stalls approx 4 times a week. The battery / alternator light very occasionally flickers and It tends to cut out when i've come off a motorway onto the slip road. Any thoughts ?

[dr_mat 0]

Use the search, luke, been discussed many many times before. No simple answers.

[emax 0]

I'm about to (temporarily) revert my manifold back to standard to carry out some accurate leak down and compression tests on a warm engine (a little trickier with a Schrick in situ). I took a look at the star bolts that hold the plastic guide for the HT leads in place and both have been rounded, one badly. Does anyone know the part numbers for these as I don't fancy putting these back in when I'm finished?

[dr_mat 0]

Ick, rounded? Who by..?! There's more than two of them. Think the part number is:

 

12 N 905 081 01 BOLT, WITH POLYGON SOCKET HD. M6X18

 

http://www.elcats.ru/audivw/nn/vag4.asp ... &cyl=&vol=

[dr_mat 0]

Hmm could also be this one:

 

16 021 133 915 B SHOULDERED NUT WITH MULTIPOINT SOCKET HEAD M6

[emax 0]

Thanks Matt,

 

Looks to me like the latter. Thanks for the links to the site, I'll need to brush up on my Russian in future ;-)