Porsche Tech Letters - Tech Review - European Car Magazine

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1977 Porsche 911 Carrera
When I try to start my car, it makes a noise like a typewriter (sounds like the starter or alternator isn't starting). The car cannot start. The battery is okay, the dashboard lights and radio are working. Do you have any idea what it could be?
Lionel Bourdrel
via the Internet

Sounds like it could be a starter motor problem where it is not engaging the flywheel properly. Have a new starter put in, but remember it is an easy task, so don't let the mechanic charge you too much. Sorry, that's my best guess from across the Internet.
--Mitch Rossi

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1980 911 SC
First I'd like to mention that I really enjoy your magazine and have subscribed for several years now. I'm considering the purchase of a European 1980 911SC imported to the US in 1985. It has documentation that says it has been made EPA/DOT compliant. I'd like to find information as to how the car, in particular the engine/drive train compares to the US version. For example the horsepower rating and transmission gearing/ final drive ratios. Are there any other considerations. Any information or sources would be greatly appreciated.
Randy Uhlman

Bringing gray-market cars into the U.S. was very popular in the 1980s because of the every tightening standards of the EPA. It was, however, a very troublesome endeavor. As the SC you are looking at has been in the States for 17 years, it would seem that its documents are in order. But I would verify everything with your local DMV and automobile insurance company before purchasing such a car.

On the technical side, the European 911 SC and the U.S. versions both carried the same 915 transmission. The power advantage of the European car was only eight horses at 188 bhp. While the U.S. car had 180 bhp, it had a higher compression ratio. (9.3:1 vs. 8.6:1). Torque ratings for the U.S. car vs. the European were 175 lb-ft at 4200 rpm vs. 188 lb-ft at 4200 rpm, respectively. The increased compression clearly did not make up for the U.S. engine being equipped with a three-way catalytic converter and oxygen sensor. With this minor difference in horsepower, you should be sure the price and condition of the car make it worth any trouble you might encounter with the documentation. --Mitchell Sam Rossi

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914 2.0 Makeover
I recently bought a 1975 Porsche 914 2.0. It's a beauty-the sound of its two Dellorto carbs is amazing and it's very fast! That's my problem: The brakes are terrible! I am looking for a kit to make sure I don't kill myself next summer with this toy. I am actually very surprised to see that Automobile Atlanta and Performance Products don't seem to have anything to offer.

I also want to remove that ugly vinyl covering from the door panels and the dash. Could you advise me on what material to procure or on any company that has a material with a better finish and nice colors? I think I'll go for a dark red (my car is black on black). Your help will be very appreciated!
Yan Vaillancourt
via the Internet

There's nothing like enthusiasm and a new car. We've all been there and loved it, and later realized that our pride and joy wasn't as perfect as we at first thought. We suspect your dual Dellortos make the car sound faster than it is. There's nothing wrong with that, nothing at all, as long as you are aware of it. There are two schools of thought on old cars' brakes: They are bad because they are old, and they are bad because they are neglected. Sometimes, it's a little from Column A and a little from Column B.

The first thing to do is make sure your braking woes are not caused by neglect. Is everything working the way it should? Are your pads high quality, the fluid fresh, the brake lines solid? Are the calipers in good condition and pistons moving freely? Even with the 914's unvented front rotors, an aggressive street pad will make a big difference. If everything is working as designed and you still don't like it, you need to think about upgrades. The brakes from virtually any air-cooled 911 will bolt onto your car, but you will have to convert many more parts than just the brakes to 911 spec: everything from the hubs out to the wheels must change, because the 911 used five wheel lugs versus the 914's four.

A significantly less costly solution is German Parts and Restoration's BMW 320 caliper upgrade, increasing piston size and thus caliper clamping force by about 30 percent. This was used on GPR's own 3.2L 914 featured in the July 2001 ec and brought out to represent us in the G-Force Challenge (ec, January 2002).

James Sly's Project 914 for the streets has had all three options in its lifetime: Upgraded stock parts and pressure distribution (ec, November 1995, p. 78), a big 911 brake swap (ec, June 1996, p. 96) and GPR's BMW 320 calipers (ec, May 1997, p. 40).

As for "kustomizing" your Porsche's interior, my advice is "Don't do it!" Okay, We admit we actually like the Spartan, vintage feel of the 914's interior. Having seen a lot of 914s over the years, we can say the ones that looked best at the time look best still: they look the way God and the factory made them. Whenever someone adds a custom touch, it seems to look good for about half an hour. Then our eyes start to like the simple honesty of originality. It could be that your car has been redone poorly, in which case replacing whatever is there with stock or stock-like parts would be my advice. World Upholstery & Trim is a good source of original-like replacement trim and can probably help out with non-original materials with original fit.

World Upholstery & Trim
(800) 222-9577
(805) 921-0100
Fax: (805) 921-0101
www.worlduph.com

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Forcing the Issue
I was wondering if you knew of a forced- induction system for late-model Porsche 928s. I've been looking for either a turbocharging or supercharging system.
Joe Sarrasin
Chicopee, Massachusetts

Adding boost to Porsche's largest displacement engine is certainly an interesting prospect. Unfortunately, nothing you can do to that engine (some would say this includes basic maintenance) is inexpensive, and many people who try to achieve greater performance through forced induction on any car seem to think of it as a shortcut to avoid spending money. We searched our archives and didn't come up with a single mention of a forced-induction 928. We consulted a local 928 expert who told us he wasn't aware of a fully engineered kit that he was able to recommend, though he was able to give off-the-record summaries of experiences people have had trying to make blown 928s run, both past and ongoing.

There are rumored to be some very low-boost 928 S4s with 10,000 or more miles on the systems, but our source didn't know the details. The other cars he was aware of have all eventually had issues with driveability or reliability. One system is under development by a reputable tuner but is in the earliest stages of pure research and development. The representative we spoke with told us it is uncertain whether the system will ever be sold to customers, and if it is sold, it will be some time before that happens.

Our best guess about how much it would cost to turbocharge a 928 with thorough engineering and proper development and testing time is between $15,000 and $30,000. It would have modern turbos on well-designed manifolds and proper fuel management, which means either a completely reworked factory ECU or stand-alone engine management. Getting the airflow through the front of a 928 that would be required to meet the cooling and intercooling demands of the car would be difficult, if it's possible at all. Turbocharging would be well worth it to the user but very difficult to accomplish and would take a very long time to get right. The second car would cost much less and take less time, but we expect it would be difficult to market a kit that was done properly at a price that would sell enough to make it worth the time.

An alternative exists if you are not concerned about originality. Renegade Hybrids sells Chevrolet V8 power conversions for Porsche 911s, 914s, 928s and 944s, citing low initial and continuing cost, low maintenance, high reliability and prodigious torque and horsepower. Renegade reported that many customers' cars are simply daily drivers, the owners of which love their cars and want to continue enjoying them and would otherwise be forced financially to scrap their vehicles when something major goes wrong. If you choose this route, Porsche purists may try to spit on you, but it's possible you'll be so going so fast they won't have a chance.

Renegade Hybrids
4640 S. Valley View, Unit E
Las Vegas, NV 89103
(866) 498-2421
(702) 739-8011
info@renegadehybrids.com
www.renegadehybrids.com

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Flannel or Leather
I have a problem that I hope you can help me with. My car is a 1988 944 Turbo "S" and I'm looking for some burgundy flannel material to redo my seats with--I want to keep it as original as possible. I've checked with numerous upholstery shops and Porsche dealers in the States and here in Germany. I've even contacted the factory. But no one has any ideas as to where I might find the fabric. My only other option is to redo the interior in leather. Any assistance on your part would be greatly appreciated, since you are my last resort.
Dave Collins
APO Germany

It seems you have made an exalted (and exhausting) effort to find the correct material to reupholster your 944 seats. As you're in Germany and we're here in the U.S., contributor Mitch Rossi, of Project 911S, could come up with only one viable suggestion: Contact your local Porsche clubs and find someone who has come across the same problem. If you're lucky, they might have been able to find an acceptable alternative. Your other choice of reupholstering in leather is a viable one, as the 1988 944 Turbo S could be ordered with leather seats, option number M409. Good luck.

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911 915 Gearbox Mods
I have followed your rebuild articles of the 911 closely. You mentioned the WEVO gear-shift modifiicatoin to the Porsche 915 gearbox. Other than being pricey, I don't know anything about it other than it improves shifting. Do you have an opinion on the setup, its pros and cons, difficulty of setup, advantages? I am just about ready to rebuild my box and would appreciate your input.
Malam
via the Internet

Mitch Rossi, Project 911's author, has admitted that as the project car is still under construction, he has yet to try the 915 with the WEVO system. But so far he has heard nothing but excellent reviews about how it has improved the box's shifting from his friends who do have it in their cars. The advantage he hopes to gain from the system is to make the shifting more precise. From time to time, we are all victims of a missed shift, but he's hoping the WEVO will save him from his own mistakes. While he was only a helping hand during the unit's installation, it did not seem to be a difficult addition to the gearbox, although it did take a little planning to make sure it was fitted in the right sequence with the rest of the components. Our suggestion would be to contact WEVO directly (650/595-5572) and explain your concerns. They are extremely knowledgeable about the 915 box and refreshingly helpful. Thanks for following the project series.

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What About Prices
I work exclusively on 911s and I found the "Project 911S, Part 11: Transmisson" article to be lacking an important feature of any good tech article, and that is the individual cost of items and the total cost. Why are you not listing item prices?
Frank Ehrentraud
via the Internet

Unfortunately, we disagree that the cost of products used in the articles would make the stories any better. We're sure there are a number of things that would make them better, but a price list isn't one of them. Case in point, the transmission article. Mitch Rossi has listed the manufacturers of several key components used with the 915 so interested readers could contact them. But he couldn't offer the price of a 915 gearbox because the price across the country varies. What he paid for his (he actually traded some Fuchs for it) and what someone else would pay is subject to the market. There is also the question of the mechanic's hourly charges. Mitch has no firsthand knowledge, but we bet what a Porsche mechanic charges in Los Angeles differs from what one in Effingham, Ill., charges.

Also, Mitch is flattered that you would consider his articles as "Tech" pieces. "I hope no one has mistaken my stories as inference that I am an expert on the mechanical aspects of the 911. I am not. I have, however, turned to experts to help build a competitive club race car from an early 911S. My expertise, (a subjective term) is only in passing on their knowledge to the readers."

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Good or Bad Deal?
Hello. I am wondering what ec's staff knows about mid 1970s Porsches. Reason: I found a 1975 Porsche 911 SC for $1,600. I'd like to know about parts availability or this car, and if this particular year is a good model or not. Thanks for any info.
Nick
via the Internet

From your brief description we are wondering what someone is trying to sell you. The 911 models from 1974 to 1977 were either the 911, 911S or the Carrera. The 911SC was not introduced until 1978. Also, if your quote of $1,600 is for the complete running car in presentable condition, then it is definitely a good deal. For this price, however, I suggest you take a very close look at what you are buying. If the price is $16,000 and it is simply a 911 or a 911S, it is overpriced even for a concours car. If it is a Carrera, then the price might be more understandable, but again, it should be in excellent mechanical and cosmetic condition.

Be aware that the 2.7 engine of the '74-'77 models was not Porsche's finest flat six and is considered to be somewhat underpowered and troublesome. Parts for all of the 911 cars are readily available. Only with the very earliest models would you possibly have difficulties finding exact replacement pieces. As with any used car, and especially a Porsche, you should have it thoroughly inspected by a reputable mechanic for corrosion, previous damage and engine fatigue before agreeing on a price or sealing the deal.

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Shocking Symptoms
I have a 1982 Porsche 930, and on moderate to hard acceleration the front end goes up and the rear end goes down. At rest when I push on the fenders it feels tight and solid. Is there a way to tell if the shocks or torsion bars are worn out?
Brent Smith
via the Internet

Torsion bars are made from extremely tough metal alloys and will rarely break unless they have been weakened by corrosion. The torsion tube, however, can fail. Yet, we have only seen this happen to very early 911s and hard-driven race cars. Given the age of your 930, it is far more likely that you are in need of shock absorbers. The reason why the stationary car still feels sold when pressed upon is because this action does not test the shock absorber but rather the torsion bar. Because of the engine's torque, the 930 had a tendency to squat during acceleration. In order to offset this, Porsche equipped your model with extra hefty rear torsion bars. Thus, in bouncing the fender, you are trying to twist a very ridged component designed to resist just such action. Barring any other weakness in your 930's suspension, the fact that the front end goes up and rear end goes down under moderate acceleration is basically all the test you need to determine the poor quality of your shock absorbers.

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914 Owner and Proud of it
First let me say I really enjoy your magazine. I travel a great deal and european car helps make the trips bearable. This is the first time I've ever felt compelled to write a letter to a magazine, but your response to Mr. Kyle Petrich regarding turbocharging Porsche 914s in the April 2001 "Tech Letters" section really made me take notice.

I'm an active participant on Rennlist, one of the largest online communities of car enthusiasts on the Internet. On the 914 list there are at least three 914 turbos with several others either in the early stages of construction or being considered. I am the proud owner of one such beast, a 2.0L using a turbo from a mid-'80s Chrysler pulling through a Weber sidedraft carburetor. Another one uses a 1.7L with a 924 turbocharger and CIS injection. The third is nearing completion and uses a 2.0L and the stock D-Jet injection. They're certainly not "knuckle-dragging conversions," and mine, at least, does not intrude on the trunk at all.

My car is a beautiful driver, capable of daily duty while scaring Mustangs and Camaros on a regular basis. I'd happily take it on a long trip without a worry, because it runs well and, using a modest 7 psi of boost, it has proven quite reliable. I wouldn't run my car at higher boost levels because the draw-through design doesn't allow it, but both the injected cars will run significantly higher, using sensible improvements like Raceware case bolts and head studs, separate oil coolers and air/air intercoolers.

The Type 4 engine responds very well to turbocharging and can make silly amounts of power from such modest beginnings. They are very popular in VW dragsters and sand rails, not to mention "Cal-look" street cars. There are several manufacturers who specialize in high-performance aircooled fours, and turbocharging is a popular conversion. Done right--and that's the main point--they can be very reliable for those with a desire to be different. And let's face it, you wouldn't be driving a 914 or a Bug without a little rebel in ya!
Mark Litherland
Atlanta, Georgia

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914s Rule
In the April 2001 edition, you received a letter from Kyle Petrich in Hong Kong asking about more power for the Porsche 914. There's an e-mail list for the Porsche 914 through YahooGroups that I think Kyle might benefit from: groups.yahoo.com/group/914. We have been discussing different ways to get more power for our 914s. A couple of people are working on adding a turbo (Mitsubishi/Saab/Subaru/Toyota) to their cars, while others have added either the six from the 911, a Buick V6 or a Chevy V8. We are very passionate and enthusiastic about our 914s and we like to help whenever we can.
Scott Carlberg
via the Internet

We love to hear from people who love their cars. Having your car make you happy is the most important part of being an enthusiast, after all. We've seen almost every kind of engine swap in the 914 chassis over the years. Some were rolling art, others were downright pitiful/scary, but the one thing they all had in common was that the person who did them was very proud of himself and loved his car.

It's very difficult to judge a car without seeing and driving it ourselves. We try to use our accumulated experience with both factory new and tuned cars to steer readers in the best direction. What we are about to say is something we hate to say in public, but a mid-'80 Chrysler turbo with a draw-through Weber carb is exactly what was meant by "knuckle-dragging conversion." Mid-'80s Chrysler turbos were cool at the time because they were the best that was reasonably affordable, but they sucked by today's standards. They were laggy, inefficient and prone to lack longevity. Assuming linearity of power output with manifold pressure, a 90-hp atmospheric engine probably makes about 135 hp at the flywheel with 7 psi of boost.

This is our idea of a non-knuckle-dragging aftermarket turbo: Engineering editor Dan Barnes recently dropped in on a club dyno day where modern, multi-valve, watercooled 2.0L four-cylinder engines were being flogged. Using a modern Garrett turbo, proper intercooler, factory harness and reprogrammed factory ECU, the champion of the day had put 401 hp to the wheels, running 22 psi and pump gas. It was a perfectly safe, polite, street-driven car, though it certainly would give something up in durability and required maintenance when compared to the stock 145-hp naturally aspirated engine. Obviously, a Volkswagen air-sucker engine won't be able to perform like that or survive such abuse without a tremendous investment in race-level parts, but the example illustrates where we're coming from.

On another modern car, we saw that replacing the sensor manipulation schemes a tuner included with his supercharger system with a good aftermarket programmable EFI system allowed an enthusiast to achieve the same output at low-boost settings as the tuner's intercooled high-boost system did with the sensor manipulation tricks.

The point of this response is that technology and precise management rule, especially when boost is involved. The payoff is dramatic. Personally, it would be difficult for us to do all the work of building a turbo system from scratch without knowing it was the best we could possibly do. Thanks to the recent popularity of import performance cars, the state of the art in aftermarket turbos has progressed rapidly. We would love to see ec's readers keeping up with the fans of cars that came across the other ocean.

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Corrado Versus 944 Redux
A Volkswagen Corrado versus Porsche 944 is a fair camparison (see Tech Letters, ec 11/00), and I might go with the Corrado as you suggest. But a 944 Turbo? Sorry, the Corrado does not stand a chance as you imply in your answer to Don Ulmer. I love Volkswagens and I would have to seriously consider putting a Corrado on my short list, but not because it will keep up with a 951 Porsche! I don't care how much you bolt onto a Corrado, it will never perform like a massaged 944 Turbo. A lot of what you said about 944s is true, but don't mislead your readers into believing that their Corrados are going to become "944 Turbo eaters." I have had the pleasure of driving both stock and modified versions of these cars.

A little advice for Corrado owners: Don't mess with a Turbo. Once you exceed the 200-bhp mark on the VW, torque steer becomes a serious issue. Differential upgrades help, but a 944T can be easily upgraded to 275 bhp. Driving the rear wheels makes a difference with this amount of power. And I have yet to drive another car, other than an M3, that handles as well as a 944. Will the Porsche 944 Turbo cost a little more to own? Probably. Is it worth it? Absolutely!
Mike D.
New Paltz, New York

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More Power for 914s
I'm sending this from Hong Kong where I've been stationed for a year. Your magazine is helping keep me sane while in a place where there is no opportunity to drive. Back in the U.S., I have a 1974 914 2.0L and, of course, I love it. Wonderful handling, targa, all that's good about it. But, as it's been said since 1974, it just lacks a little pep. People talk about engine swaps or pouring money into the engine, but I never hear anyone talk about boost.

It seems like a great solution. I've been looking and I can't seem to find a turbo or supercharger for it. With all of the Porsche and Volkswagen tuners in the world, it seems there should be something. Am I missing something?
Kyle Petrich
Hong Kong

Cars making good use of forced induction will frequently "cure what ails it," whatever that may be. Unfortunately, boost means heat and on a hot day even a stock 914 can have problems getting rid of the heat it produces.

Senior Editor Les Bidrawn, who used to own a 914 and has seen countless tuned versions over the years (many in their darker moments), heard us mumbling something about turbo 914s and immediately said, very loudly, "Bad idea!" Just to satisfy our curiosity, we dug through past issues of ec, going back into the VW&Porsche days, and found only five mentions of 914s packing forced induction. By todays standards most were rather knuckle-dragging conversions--a couple being home-brew setups that didn't run right, even by their owners' admission--and they all seemed to intrude into the trunk one way or another.

Two of the companies responsible for better-engineered conversions are still around. One, however, asked not to be mentioned, as it now specializes in late-model Japanese vehicles.

The owner of the other said the heyday of this conversion was from 1974-80, and the last 914 turbo kit he shipped was in 1989. Having moved twice since then, he doesn't even know where the jigs are anymore. He said his cars put 163 bhp to the wheels back in the day, and the engines worked okay at boost levels up to 7 after which the case halves separated. The first six-cylinder conversion he did was shortly after he turned the boost up to 12 psi on a four-banger.

He said your best bet, if you are determined to build a turbo car, is to buy the book "Turbochargers," by Hugh McInnes, and find someone who can weld--skillfully. Published by HP Books, "Turbochargers" is available through automotive parts stores under p/n HP49; bookstores will know it as ISBN 0-89586-135-6.

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Turbo Conversion
I am starting the long process of buying a Porsche 944 or 944S. I've read a few articles in Excellence magazine about which years to look for in the 944. I am planning on a 1987 or later model with low miles. I am interested in saving on insurance and am curious if I can convert a 944(S) to a turbo, but still keep the non-turbo VIN. Does this sound like a practical idea? I hope so. Now for my second question. I live in New England and am tired of the oil debate with my friends and the parts guy. What brand do you prefer, and does it really matter? My wife has a 1996 VW GTI 2.0L. She upgraded to an Autotech Q-chip, the P-Flow cone filter, and Techtonics Tuning Magna Flow exhaust. Does this change anything as far as what weight I should use? The dealer tells me 15-40 or 15-30. The parts guy says don't listen to the dealer. Well, I don't want to listen to him, but I will listen to ec.
James T. Dickie
Branford, Connecticut

The short answer to your first question is "No." The long answer is, "Heck, no." The even longer answer, probably the one you were looking for, is that the only way you should even consider doing such a conversion is if you got a really sweet deal on a wrecked 944 Turbo that you knew to be in excellent condition prior to the mishap. Then you would have to get complete shop manuals for both cars, tear them both down, and remove, inspect, rebuild or repair, and reinstall every part that was different. Even if you have the space and equipment to do this, you will probably be better off in the long run just saving your money for a Turbo. After all that work, it would be difficult to convince anyone else that your car was anything more than a hacked-up Porsche, the kind of car that wise buyers don't walk but run away from. If you did need to exercise your insurance, you would at best be paid for what your car started out as, at worst run into complications having to do with a car that had a turbocharger and was insured as if it did not.

I have never seen data to show that any one of the major, high-quality conventional oils was superior to the rest, but I would stay away from the discount-priced no-name oils. We asked Aaron Neumann of Neuspeed about VW applications. He reminded us that older VWs, such as 16Vs and VR6s, are known for running high oil temperatures, 240-260*F on the street and as high as 300*F on the track. This definitely counts as severe duty for a motor oil, though 2.0L cars are less extreme. Oil coolers were popular years ago, but with the rise of synthetic oils, it is simpler to just use a synthetic or name-brand synthetic blend and change it often.

Aaron recommended 3,000-mile change intervals for hard-driven cars, rather than the extended intervals listed in the manual. For Southern California's climate, 20W-50 year round is wise. In winter, lower viscosities are better, especially the cold rating. Most engine wear occurs when the engine is cold, and oil that pumps more easily when cold gets where it needs to be and starts working sooner. Synthetics shine here, as well. The changes you have made to your wife's car make little difference, the more important factors being how you drive it and the conditions where you drive.