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  • 2 weeks later...

Yup. The torque you would normally get at 4000rpm, you get at 3000rpm with a Schrick.

To get a genuine 220-230hp (from a 2.9) you need a big bore throttle (a bigger plate, not a polished ebay special), a schrick and 268s. Plus a remap of course.

When you price all that lot up, a charger makes a lot more sense. You can even buy an R32 conversion for less than that lot!! 280hp all day long and tonnes more bottom end torque than any nasp or charged 12V can ever get close too.

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Is that strictly true fish (kev is it?). The Schrick mani has a smoother air path at the TB but the plenum volume and runner lengths determine the peak torque characteristics, therefore it'll likely be helmholtz frequency tuned for a standard engine set-up and it's peak torque characteristics for the std cams etc seeing as it was going to be a std option from VW. Or is it they have a varying resonance and std's do not via a change over in pathways? (6 years ago I last built a 12vt and just fabbed a srim for the peak torque of the turbo/boost we were using, easier than forking out for these things!).

By adding varying cams and bigger TB's etc (obviously depending on spec) you would automatically be pushing the peak torque values higher up the rev range.

Therefore would a Schrick actually be as potent seeing as the engines power/torque characteristics have been subsequently changed with the mods? Get a dyno print out for peak torque values and then get a good fabricator to freq tune you a manifold for that would probably cost about the same nowadays, especially with the rarity of the Schricks.

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P.S. I thought I should add this:

With regards to the design and development of the inlet manifold there are also other aspects to take into account. As an example my last mani development was for my MR2 turbo. This uses a TVIS system and this differs from, as an example, the 24v mani's as the 24v has it pretty much built into the plenum. With my tubby it has a sort of twin runner design and a horizontal flap system that is closed until a set rpm. Basic physics/flow characteristics denotes that a smaller orifice that a quantity of air has to dynamically flow through means a higher speed at the expense of a certain volume. However, and this is important, the twin valve inlet of my 16v engine meant that both valves, often with a divide, needs to receive a certain quantity of air and equally, this is so that the tumble in the cylinder is equal (which can then relate to the piston design but one thing at a time!).

With the TVIS the twin runner shape meant it was squeezed through a much smaller opening until the set rpm when the valve opens the plate to allow more flow through and both halves of the twin runner design were utilised efficiently!

Other aspects to take into account are also the inlet port design and even the runner taper angle can make a big difference, as too cams, turbocharger size, porting work (in respect to area vs flow, ingested air volume etc) and actual peak torque values of that specific set-up.

Therefore when someone claims that a Schrick will not give x it may well not but they may not know that the specific values required to be used on a professionally tuned car/engine set-up have subsequently changed. Therefore you should always remember that the Scrick item was supposed to be a standard upgrade option until the money men starting making cuts and as such, if you have a plasma cutter, a bit of sheet metal and good welder doing your own is always better. More than the price of the car..... IMO doing it right is the only way if it is your baby!

Hope this helps

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Back in the day, on a stock 2.9 VR6, a Schrick VGI on it's own + a remap moved the torque 1000rpm down the rev band. Then there was a noticable kink in the torque plot where the flap opened at 4000rpm.

The remap (and indeed the OE chip for the VSR) basically removes ~ 6 deg timing from the 3000rpm region, and adds a bit of fuel to counter the postive pressure pulse tuning. If the remap wasn't done, the engine pinked too easily in the summer months. Too much for the knock control to pull back quickly enough.

Past 4000rpm when the flap is open (short runner plenum engaged) the motor felt pretty flat, so adding 268s and a larger throttle not only left the VGI's peak where it was at 3000rpm, but also fattened up the top end considerably. This was all seen on the many dyno runs Stealth have done over the years.

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its all about money v power/trq . as has been said time and time again , for the price of a shrick + remap + odds and sods ( as you always need something extra )

its more cost effective to buy a secondhand charger and map that . or has been said fit a 24v lump / ecu combo .

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Yup, agreed. I did the Schrick + 268s + TB thing many moons ago and was extremely underwhelmed by it. As Jim says, for the cost of that, I could have gone forced induction, which really does give a night & day difference.

If you want a VR6 that has bottom end torque and good up top aswell, fit a 24V! R32 in particular. For such a long stroke engine, it rips round to 7K so easily. Very impressive lump.

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