| European Car Magazine - October 1993
Wretched Excess One - Lurching Toward Success: by David K PHOTOS BY DAVID FETHERSTON
The Big Squeeze The key is Evans Engineering's propolyene glycol zero-pressure cooling system. We've written about this stuff before (see the December 1990 and October 1991 issues). Propylene glycol is an environmentally friendly high-performance coolant with properties that let it work at atmospheric pressure and higher bulk coolant temperatures (no more burst hoses or volcanic overheating failures). Its main high-performance attraction is that it cools hot cylinder heads evenly and effectively enough to forestall detonation at higher-than-normal compression ratios.
Cooling system modifications, up to all-out reverse-flow systems, are required to get the most out of it, but simple tweaks - a zero pressure radiator cap and small plumbing changes - are enough to convert an otherwise stock car. european car has already shown, through testing on the APS chassis dyno, that propolyene glycol works well enough, even under very heavy load, to prevent detonation and preserve power on a knock-sensor equipped 10:1 GTI. Evans Engineering said it would work well enough to allow up to 12:1. They supplied the coolant, and Techtonics made up a set of 11.5:1 pistons for my Audi 1984cc block (these are actually German factory pieces, beautiful, light castings made for alcohol racing engines, of all things). We were aiming for what Evans Engineering calls a "Stage II" system, which relies on increased coolant flow to deliver most of the benefits of a full-house reverse flow system. A larger diesel crank pulley, combined with a custom undersized Evans Engineering water pump pulley, increased the water pump drive from the stock 1:1 to 1.9:1. (We later figured out that on my car, without air conditioning, a stock diesel water pump pulley would have worked just as well. Cars with air and/or power steering will have to mix and match stock parts or use custom pieces, which Evans Engineering is set up to provide.) Contrary to my fears, the additional speed doesn't seem to do the pump any harm. Mine's endured a year of very aggressive driving without complaint. And increasing the flow rate really works; we played with different size pulleys at various times, and detonation was gradually dialed out as flow increased. Not altogether, it turned out. That required, on Evans Engineering's advice, a head gasket modified to direct more coolant to the very hot exhaust side of the head. This is no cut-and-try project; the size and placing of holes in the head gasket helps determine the pattern and proportion of coolant flow in the head and is very carefully developed by the factory. Oettinger, though, can be counted on to have done their
homework, and their gaskets feature several additional and several enlarged gaskets on the exhaust side. We copied that, and it worked very well. These gaskets no longer seem to be available in the U.S., but both Techtonics and Brian's Garage can supply modified factory pieces. (A word of caution: This coolant will burn if you get it on hot parts like exhaust manifolds or turbo housings. Make very sure that fittings on the hot side of the engine, like turbo bearing cooling lines, are secure.) The result of the cooling system buildup is extraordinary. My car, even with all the cylinder-packing breathing enhancements eventually grafted on to it, is happy with premium gas, stock advance, and the hot 1986 knock-sensing maps unless the weather is really hot, when it starts to ping on part-throttle. Resetting to the milder maps banishes all knock. Brian Brown, a VW enthusiast in Milwaukee, performed a similar conversion at 12:1 on a less all-out Scirocco. It worked perfectly, even with a non-knock-sensing early-model GTI ignition system. With the knock-sensing ignition, he runs the hot maps and 12 degrees advance. This in an incredible accomplishment: There isn't a factory car in the world that does as well. The extra torque is enough to make you think you're a gear - or two - lower than you are, and the flexibility is amazing. Near my parents' house in Maine, a fast two-lane road winds through a small-town speed zone that includes a steepish hill. I can drive in at 70, crawl through town and up the hill at 25, and accelerate briskly away - all without changing down from fifth! And my guess is that a similar conversion would work even better in conjunction with the more sophisticated later-model heads. Anybody want to try for a 200 bhp 12.5:1 two-liter 16-valve? A high-boost 9:1 Corrado?
In Goes The Good Next in line down the intake tract is a controversial piece of VW performance news (Sam Michalopoulos, one of theBrian's Garage regulars, figured this one out). Meet the SewerPipe. Replacing the S-shaped plastic pipe that runs from the boot on top of the air meter to the throttle body, it's nothing more than a 3-in, inside diameter piece of copper tubing with a 38-degree bend toward one end, flattened into an oval to match up to the throttle body. Installation is a matter of loosening three hose clamps, rotating the airbox boot a little, slipping the SewerPipe in, and tightening everything down again. Nearly the same piece, merely a little shorter on the long arm, will fit a Golf. Does it work? With one exception, every car we've tried it on, even a dead-stock 1.7 Scirocco, has seemed to have gained strength all through the rev range. Subjective impressions have been that power comes on earlier, the mid-range is fatter and the motors stay on song right up to and through redline. It was one of the last parts in this buildup fitted to my car, which even with a Quaife torque sensing differential now spins its wheels - both wheels, with sticky Yokohamas on 7-in, wide wheels - not just in first but also in second gear. And, curiously, it seems to have had some positive effect on several cars with low-end detonation problems: One Golf that knocked at stock advance is fine, post-SewerPipe, at 12 degrees. Strange, but how true? For instance, editor Greg Brown's A1 Jetta, fitted with a Techtonics 1.9 and a Streetport II head, gained nothing from the SewerPipe. Neither on the APS chassis dyno, nor on the road, did the pipe make any difference. My guess is that Greg's car, which is already making almost 140 bhp through an almost stock intake, is already too maxed out on either the induction or exhaust side to benefit. However, tests run by Techtonics came to the same conclusion. Faced with this, we organized an on-the-road test with a variety of different cars. The results were interesting and seemed to indicate improvements, although the mathematical scatter and the less than state-of-of-the-art timing equipment muddled the objective numbers. Whether it works or not, it appears that this is a piece that falls outside the emissions regs. Until that's certain, Brian's Garage is selling them for off-road use only. ExtrudeHone
ExtrudeHone claims not only improved flow but improved smoothness from their procedure. In addition to opening up the air passages, they balance flow through each runner for, in theory, even cylinder packing and better dynamic balance. I started with a late-model Audi 80 intake manifold, which offers a bigger plenum and longer runners, but also required extensive welding to close off the stock injector ports. Sticking with a moderate port size for good velocity, ExtrudeHone worked on the runners, and especially the join between the runner and the plenum, and improved flow significantly over stock. Superhead The swap is a lot harder than it sounds, which is why the BMW valves are prototype only and will not be featured in future Techtonics StreetPort heads. The BMW stems are too long, so they have to be trimmed to fit and have new keeper grooves cut. The stem material is so hard that Techtonics has found only one place that can do it (using a grindstone!), and then apparently only when the proprietor feels like it. The valves from VW's new crossflow 8-valve head also have 7mm stems and could be a good substitute when they become available. Techtonics has recently made further progress in porting techniques, which has resulted in a Stage III StreetPort head with better performance still, but without the added cost of the BMW valves. Cost of the head with the prototype BMW valves is $1275, far too expensive for what the market would bear. and for a tiny airflow gain. Three prototypes were completed, but the heads with BMW valves will not be offered for sale. Currently, Techtonics is modifying stock valves to the reduced stem diameter for $75 extra on the $675 price of a Stage II head, bringing the new Stage III total to $750, a $550 drop in price. (When did anything so good drop so far in price?) And that's great news because even a Stage II head makes as much power as a 16-valve: One fitted to a very mild 1.8 - small throttle body and almost stock manifold - made 138 bhp, relative to 136 for the European 16-valve 1.8. With additional breathing work there's obviously more to come. On Collin's flowbench, mated up with either a Techtonics or an ExtrudeHoned manifold, mine moved as much air as his old 161 bhp manifold/head combination, even with its much bigger ports. Pulling the same amount of air through smaller ports means higher port velocity, better cylinder filling, more turbulence and more low-end torque. And Collin's extra attention to balancing the flow numbers for each cylinder makes for very smooth performance. I'm still sorting out which cam suits it best, but even with a mild G-grind it climbs for the redline as eagerly as any 16-valve. Except that that characteristic high-rpm surge starts at 3000 rpm instead of 4500... Clean Machine So What'll It Do? It's also a very sweet car. It's wonderfully eager; the slightest pressure on the throttle brings instant urge. There's serious acceleration from below 2000 rpm, and even in fifth by the time you break 3000 rpm you're really moving. The real powerband starts there, with a flood of power all the way up to beyond redline. The torque peak, at around 4500 rpm, is enough to cause on-the-fly dry road torque steer - again, even with the Quaife - in third gear! So, so far so good. We think there's a little more to come, what with one thing and another, and then there's the question of wheels, tires, and suspension work to bring the traction and handling back into balance. We're working on it; watch this space. Wretched Excess Suppliers Brian's
Garage Evans
Engineering ExtrudeHone Techtonics
Tuning Ron's
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Back
in June, 1987 VW & Porsche - for such were we then - ran a story
about Techtonics engine builder and general hot-shoe Collin Gyenes'
personal car. Cohn's Jetta was fast. Its two-liter 8-valve motor
relied on tried-and-true tuning deep - breathing and big compression
- to make big power. It had 11.9:1 pistons, a custom head with
huge ports and oversize exhaust valves, and ported and polished
manifolds with days of hand labor in them. From the outside it
looked almost stock, but it put out 161 bhp on Techtonics' dyno,
with a wide powerband and tons of torque for sweet, easy driving.
What it was not was streetable. The high-compression motor needed
aviation gas to live; for pump fuel Collin had to put in 10.5:1
pistons, which unfortunately took the edge off its heroic performance.
To this day, though, its high-compression quarter-mile timing
slips - 14.73 sec at 93.75 mph - rank among the best european
car has seen for a normally aspirated Volkswagen. 
A
lot has happened in the VW high-performance world since 1987.
Can technology put on the street, today, what was tantalizingly
out of reach back then? The answer, happily, is yes, and we've
demonstrated it with a major makeover of european car's East Coast
project GTI, the "Lurching Toward Success" car that's been the
subject of several previous stories. This article will detail
the core engine work, which has been a resounding success; it
ranges from major mechanical surgery - for only the most committed
- to more subtle touches for every extra bit of power. Articles
to follow will cover one more major engine modification, and chassis
work to balance the fire-breathing motor. And thanks here at the
outset to the many, many people who helped bring this project
together; first and foremost, Brian Mushnick, ace high performance
wrench at 
