turbo or supercharge ?

I looked into supercharging my 2.5 tiptronic boxster last year as it was not recommended to me to use a turbo(we didn't think that the tiptronic would take it)
the other option to get more mph was changing exhaust and chipping the ECU.
having sold the 2.5 and bought an S instead did any of you upgraded your S to get more speed and for what price and which system?

[nastyboxster]

I upgraded from a 2.7 to an S a few months back and is very happy with it. Upgrades were the B&M shifter and the Evo air intake.

The shifter made the car feel sportier and would not go back to a regular shifter.

I just put in the Evo air intake and it is sweet! It suppose to add only about 10hp, but it feels much faster than that (maybe it's the sound). Also, the sound from the intake is incredible. I haven't turned my stereo on for the past few days just to enjoy the sound of the engine.

I'm looking into the 2nd cat bypass right now. As in my previous post, I''m going to a custom muffler shop to see if they can custom make the bypass pipe instead of paying $500 retail.

To get an extra 35hp, you will have to spend retail about $3500US. - ECU, 2nd cat bypass, air intake and muffler.

hi there do you find the short shifter stiff in second gear? it is a thread somewhere else on the forum and many people find the original gear change stiff when cold and the shorter shifter even stiffer

[nastyboxster]

It is a little stiff when it's cold, but you get use to it. I wouldn't have notice if you didn't mention it.

Great on track days, specially downshifting to 2nd before a turn.

I would do the Evo first if you want to be yelling HOOORAY on 3rd gear at 100mph.

[deliriousga]

Between turbo and supercharger, I'd go with supercharger.

First, it's more efficient and quicker. The turbo has to have a certain exhaust flow before it really kicks in and loses some power since it restricts the exhaust a little. The supercharger winds up faster since it's belt driven and does not restrict the exhaust at all.

Second, the supercharger takes up less room. The turbo is harder to fit and takes more effort to install.

The plus for the turbo is when it winds up, it sounds cooler.

[MNBoxster]

Originally Posted by deliriousga

Between turbo and supercharger, I'd go with supercharger.

First, it's more efficient and quicker. The turbo has to have a certain exhaust flow before it really kicks in and loses some power since it restricts the exhaust a little. The supercharger winds up faster since it's belt driven and does not restrict the exhaust at all.

Second, the supercharger takes up less room. The turbo is harder to fit and takes more effort to install.

The plus for the turbo is when it winds up, it sounds cooler.

John,

A couple points, Supers are not more efficient than a Turbo. It's efficiency drops off rather quickly. Another disadvantage to the Super is the Parasitic Loss since it draws Crank HP. In the case of the Jag XK8, at full spool up the Supercharger is drawing 86 Crank HP , there's still a considerable 100 HP Net gain though and the Super has little Lag.

The Turbo is essentially Free because it's Recovered Energy, and unlike the Super, (which can only spin as fast as the Crank, or some close derivative), the more power a Turbo makes, the more power it can make. Turbines are much more efficient than a set of vaned rotors and so don't peak nearly as soon. Turbos do Lag, some more than others, but once they get going they come on strong.

Most people do not realize the Nature of Forced Cars. They are Schizophrenic, that is they have a Split Personality - one On-Boost and one Off-Boost. This can make them less enjoyable to drive than an NA Car because unless you're very good, the Boost can Come and Go at some fairly inconvenient times, especially on the Track, such as on the Apex and such where they can upset the Car's Balance and Line.

I love the Turbo in my Esprit, but I equally enjoy the fact that the Boxster is NA - the power delivery is much smoother and it's less of a handful to drive. As always, just my humble $0.02...

Happy Motoring!... Jim'99

[Brucelee]

Actually VW has just released a new engine for the Golf that is BOTH SC and TC.

The SC runs down low and then disengages as the Turbo comes on.

The net result is a 1.4 litre engine that develops something like 170 HP and gets 35 MPG.

I will try to find the article and post it.

Good stuff.

[Brucelee]

Here is the story.

http://www.autoweek.com/news.cms?newsId=103048

[Pilot2519j]

My exposure to turbo has been limited to 2001 Audi S-4 & my wife's Allroad. Both shared the same engine 2.7 liter twin turbos. In my S-4 the lag was minimal since my car was 6 speed. In my wife's Allroad the turbo lag is more noticeable. I did have bad experience with my S-4 as one of the turbos blew. So in this issue being that the supercharger is a bolt on installation and gives you more power I would go with that option. Regardless both are extravagant in cost that make absolutedly no sense financially. I think the Boxster regardless of what year and size the engine will perform great. The 986 or 987 will never be a car to peel rubber of the mark To achieve the numbers everyone wants you have to add upwards of one hundred horses to the car. The fun factor is tremendous but the dollar factor is ludicrous

[deliriousga]

Originally Posted by Brucelee

Actually VW has just released a new engine for the Golf that is BOTH SC and TC.

The SC runs down low and then disengages as the Turbo comes on.

The net result is a 1.4 litre engine that develops something like 170 HP and gets 35 MPG.

I will try to find the article and post it.

Good stuff.

Now that's BRILLIANT!! :dance:

I love things that give you the best of both worlds.

[deliriousga]

Originally Posted by MNBoxster

It's efficiency drops off rather quickly. Another disadvantage to the Super is the Parasitic Loss since it draws Crank HP. In the case of the Jag XK8, at full spool up the Supercharger is drawing 86 Crank HP , there's still a considerable 100 HP Net gain though and the Super has little Lag.

Good point about losing the crank power. I didn't think about that. Either one would be a PITA to try and install in the Boxster because of the engine and exhaust location and no open space at all.

Originally Posted by Pilot2519j

Regardless both are extravagant in cost that make absolutedly no sense financially.

Amen! For the price, you can almost get a new, bigger NA engine (or car in some cases). I looked into it for the 928 since several have supercharged theirs and raised it to 550+ RWHP. The SC kit's over $7K while a new engine is around $5K (not to mention I only $10K for the car). Add the other stuff you need to do it right (new fuel lines, pressure regulators, etc., etc.) and labor if you can't DIY and it gets nuts. The turbo kit's a little less $$, but nobody on the 928 forum has figured out where to put it yet.

While an additional 230HP would be fun, the risks of screwing everything up are too great. I can't tell you how many people have ended up with a burning car because the old (over 5 years) fuel lines could not handle the new pressure, burst and gas flew all over the engine. Poof!

If you want something that can practically fly, you can get a factory SC'ed Mustang, Jag, etc. and go really, really fast down the highway, but I'll wave bye-bye when we exit and you can't hold the road.

NASCAR or Formula 1 , it's a matter of your taste/preference and available $$.

[BuffaloBoxster]

I think you're playing with fire by trying to squeeze large amounts of power from a motor through forced-induction bolt-ons. Have a look at engines built for forced induction and they generally have lower compression ratios, stronger connecting rods, beefed up cooling systems...

You can't just force more air and fuel into the motor without thinking about lots of other things.

[chiefsalami]

I'll just add my 2 cents. I've owned and driven both turbo'd and supercharged cars. Actually, I have a supercharged VW R32 right now that I'm selling because of having replaced it with the Box. But I digress...

Tubos are nice, can often make more power by not robbing power off the crank, but there was a very good point made about the turbo kicking in, perhaps at inopertune times. Superchargers give the feel of a NA car, because they are always making some power, and make more as the revs increase. My R32 feels just like a stock one, only with more power. No wheel hop or breaking free like my previous turbo GTI did. Granted, it was front-wheel drive, but the same effects can be had with rear wheel drive, where losing grip because of turbo spool-up can cause a spinout and a disaster.

Now, as far as requiring modified internals for a supercharger, it's not true in general. My R32 supercharger kit is a straight bolt-on with no internal modifications, including to gaskets. However, this depends on the car. VW's engine is very robust, with no complaints of weak seals and leaks. Porsche, on the other hand, is a different animal. So although you could certainly push more power out of this engine (it's certainly capable - 250 or so is pretty low for a 3.2L six), perhaps it's not the best idea without really doing it right and improving some of the other known shortcomings.

It's all a matter of weighing cost (or potential cost when things go wrong) versus benefit. Of course, throw any remaining warranty out the window when you upgrade in this manner, and these cars and engines are hard enough to access/work on already.