(Click on the pictures to enlarge)
Modifications - with approx. RWHP gain for each
Autothority custom tuned CPU +45 RWHP -note @ 13.5 psi
2.5" downpipe +12 RWHP
2.5" custom made stainless steel exhaust w/4.5" tip +10 RWHP
Autothority Mass Flow Sensor +20 RWHP
PowerHaus KKK-K27 Turbo +40 RWHP
Extrude Honed intake/exhaust manifold +12 RWHP
3.0 Bar Fuel Pressure Regulator
Big bore Throttle body +5 RWHP
Porsche turbo cup-Wide Fire Ring head gasket
Bosch Silver plugs
Cambermeister strut tower bar
VDO Boost gauge (pillar mount)
History and Driving impressions after modifications
I looked at several different 944 Turbos before finding the one. It was a 1986 model, but it had no 3rd brake light on the rear hatch window. I later discovered that the very first 951's to come to the U.S., in late 1985 were imported without the 3rd brake light, but then the U.S. passed a new law requiring all cars to have 3 brake lights, so the rest were than imported with the 3rd brake light. I don't believe many made it over before they changed the law, so I thougth that it was interesting that mine was one of the very first here on U.S. shores! Anyway, back to the car, it had about 55,000 miles on it, it was the only 944 turbo I looked at, and have seen sense owning it, that had the original leather sunroof protector/case/bag. I have yet to see another 944 turbo that has that. The very first thing I did to the car was change the tires, they were only the 2nd set to ever be on the car! The next thing I changed or was forced to change was the clutch, it was the original unit from late 1985! Also, after a couple of "high spirited" runs, it became increasingly difficult to put the car into gear. At first it was just reverse, than 1st gear, then, after taking it to my local Porsche dealership for adjustment, it would not go into any gear at all! So, I took it right back, and got the good news a day later, needed a new clutch. Final cost, $1700!!!
This was the updated clutch with the spring center, not the old style with the rubber center. After going bankrupt for the price of a new clutch, I took it easy for awhile...we all know how long that usually lasts! After a losing battle with a modified mustang coupe, not the hatchback, the one that the police use, you know the one that weighs around 2400 lbs! (who BTW was running high 12's\low 13's). I decided to take the plunge. I was surprised that the owner of the mustang knew about 944 Turbos and asked me if mine was a cup car! I chuckled a little and said no. :) I called up Autothority, they specialize in aftermarket performance parts for Porsches', and ordered their stage 2 chip set, and a quick shift kit. There were 2 chips that were changed, ( DME, KLR ) which was very straight forward, and also a "banjo bolt" that was also changed. The "banjo bolt" controls the maximum amount of boost a 944 Turbo will produce before the computer steps in. The quick shift is double adjustable. You can adjust the fore/aft distance of the throw between 2 settings, and also the left/right distance, (the space between 1st and 3rd and 5th, etc.) The installation wasn't too bad, a little tricky when your laying on the ground. At least it looked tricky, I was "helping" a friend of mine put it in. ; )
After installing the quick shift, (by simply replacing the shift linkage), there was a huge difference in the distance of the throw! It is now a really short throw, just snick-snick, a flick of the wrist! However with the left/right adjustment on the max/smallest setting, it took awhile to get used to where the gears were at now. I remember thinking countless times after shifting, "did it even go into gear?", the throw was so short.
The real point of this Saturday afternoon was the chip upgrade. I was a little skeptical of how much gain I would get from a set of computer chips, but after the first drive, I knew that everything they had promised me was true! It was a huge increase in torque all across the rev range, with a noticeable step-up in power past 4000 rpm. All though not available at the time I purchased them, they now have dyno charts proving a 40 rwhp (Rear Wheel HorsePower) increase with their chips, on an otherwise stock 944 Turbo. For $300-$500, depending on the time/distributor, this is the best bang for the buck for a 944 Turbo ever!
After getting the bug for speed, it didn't take too long to get acclimated to these mods. The next thing I did was improve the intake and the exhaust. The intake was very simple, just a replacement K&N filter. As for the exhaust side, a friend of mine had a downpipe he no longer needed, so that went on, along with a new exhaust/muffler/tip. It's hard to say if I felt any improvement with these mods, I put them on in the winter, so I didn't even drive it for 3 months. After the hibernation, I had to adjust to driving a fast car again, so I can't say for certain that I felt a noticeable increase in HP. The sound however, was greatly improved on. The 944 Turbo already sounds great stock, (it's a Porsche!), but with the addition of basically a straight pipe and one minimal muffler, it really sounded as good as it looked. It's not overly loud, it has a nice "tuned" sound, and up past 4000 rpm, it really screams! Again, the websites for these products now advertise a 10 rwhp increase for replacing the stock downpipe/Cat, and a 12 rwhp increase for replacing the rear section of the exhaust (from the cat, back). Also, I think you save something like 20 lbs over the stock unit.
The next modification was to upgrade the stock turbo to something bigger/better. I called up PowerHaus, from Tempe, Arizona, and ordered the KKK-K27. The stock turbo is a K26, and basically the K27 has the same exhaust side housing as the K26 but with a much bigger compressor side. They gave me two options with the K27, one with a 6mm shaft and one with a 8mm shaft. Basically the 8mm makes more top-end power, but take a little longer to spool up. I debated the two for awhile, but ended up going with the 8mm shaft. After I received the turbo from them, I noticed that it did not have the trademark stamp on the compressor housing that all KKK turbos have, so I called them back, and Chris told me they sent me one of their hybrid K27-8 turbos! Works for me! I also bought all new gaskets and hoses at this time (recommended). I also bought the "Wide Fire Ring" head gasket. A friend of mine, who also owns a 944 Turbo, helped me with the installation of the parts. When I asked the guys at PowerHaus how long should this take if it's your first time doing this, they told me, "give it a good Saturday". Now, we might have been able to make it, had we not needed to fabricate our own special tool to get at one of the bolts! You definently need two people for this job, one of us had to get in the car and turn the steering wheel so the steering colum would move out of the way of the impossible to reach allen screw, and then move it back again. If you change the turbo, and do the install yourself, you'll definently need the longest allen wrench you can find for this bolt! Looking back though, it wasn't too bad, only a few screws or bolts were hard to get at. After removing the stock turbo we put the two next to each other...the K27's compressor side was at least twice as big as the K26's! But we did run into some trouble after this point however. Upon putting in the K27, we discovered two problems...1. The compressor side of the K27 is so huge, that the top of the turbo now hits the bottom of the intake manifold. 2. The compressor side of the K27 is so huge, that the inlet on the front of the compressor hits the alternator! After a lot of four-letter words and fudging, we got it in.
After everything was installed and the car was running again, we were debating on whether or not you have to "break-in" a new turbo. Not wanting to chance anything, we decided it best to take it very easy on the mighty K27, and give it a few hundred miles to get situated. That was the longest wait I can remember! When I felt that it was time to put it to the max, boy, was I impressed! The pull on the car was unbelievable! It did take longer to spool up to max boost than with the stock turbo, but from 4500 rpm up, it pulled incredibly strong, with no signs of even the slightest drop in power near the top! I was very excited with this new turbo for a long time to come! Not long after all this, I got caught in the rain one day, I almost never drive the car in the rain, (only when I get surprised by our lovely Michigan weather usually). Anyways, so I was out in the rain, and the road ahead opened up a bit, so I decided to have a little fun....with the recent turbo upgrade, the car will now spin the tires while driving along in 3rd gear, and stepping on it! Before it would sometimes do this in the rain, but in 2nd gear. So that kept me interested for awhile......
The next thing I did, was installing Autothority's Mass Flow Sensor. This unit replaces the factory air flow meter, (a small 1.5" square opening), with a huge 3" inlet! It comes with all the hardware needed, and includes a cone-shaped K&N filter,a new elbow pipe connecting the turbo to the new airflow meter was needed as well, due to the K27 upgrade. I also put on the upgraded fuel pressure regulator, a new set of Nology Hotwires, replaced all the ignition components, and tried several different plugs in varying heat ranges. I ended up staying with Bosch Silver, 1 heat range colder. With all the mods done to the car, I also wanted a specific chip set for my particular stage of modifications. Again, PowerHaus, provided those to me. With all these upgrades finally put on (by the way, the installation of the Mass Flow, is really simple) the car was out of this world! Just when I thought the top end couldn't get any better! It just pulls and pulls! Putting on the Mass Flow, you can now hear all the air being sucked into the engine by the almighty K27! Wow! I've owned other modded turbo cars before, but the "sucking" sound was nothing like this! What's even better than this, was when you shift, all that air gets blown back out, and the blow-off valve sound is insanely loud! Man, I still get excited just talking about it. Needless to say, I am quite satisfied with the level of performance my 4 cyl. Porsche now has!
I am finally getting around to updating this section of my website, mainly due to the great number of questions I have received about the 944 Turbo, modifications to it, and comparisons between the 951 and my Supra Twin Turbo, along with various other comments...Let me just start with a little more details about the modifications I performed on the car. First off, for some reason I could never boost beyond 14 psi, the majority of the time I was right around 13.5 psi. Even with the first mod to the car, the Autothority stage 2 chips, I never did reach what they said my car should be at, 1 bar (14.7 psi). Yes I know about the Banjo bolt that came with the kit, and how you can drill the hole to make it slightly larger if you were overboosting, but what about underboosting? At the time I only had the stock boost gauge, and that showed I was dead on 1 bar, (the gauge actually reads 2 bar, but remember that is with absolute zero at 1 bar, which means 2 bar on the gauge is 1 bar). It wasn't until I had done a few other things, that I installed an aftermarket boost gauge so I could check what I was boosting more precisely. At one point when I had done all the modifications to the car, I even switched the Banjo Bolt out of a friends' car, who was pumping about 18.5 psi, only peaking, it would taper off and hold at about 17 psi. But that made no difference in my car, it accelerated exactly the same, holding on to almost 14 psi all the way to redline in 2nd through 4th. So, it didn't take to long to conclude it was in the cars computer chips, somewhere, I was being limited to 13.5 psi! Cars with similar setups to mine were in the neighborhood of 1.1 to 1.25 bar, or about 16-19 psi. Eventually I sold the car, never finding out exactly what it was.
As far as some quick comparisons go, if you take a beefed up 944 Turbo, and line it up next to the newer (although some are now extinct like the 951) Japanese sports cars the old Porsche should hang with or beat almost all of them, due in part to its lighter weight and given equal drivers, etc, etc....But this would only be the case if the Japanese cars were stock, having owned them both, I can say from experience that its great to see the almost 20 year old technology in the Porsche giving the young pups a run for their money! But after modifying my Supra TT, I wouldn't place any bets on my 944 Turbo, except for 2nd. That is strictly the straight-line test, and I know people can argue about this until everyone is blue in the face, but I have had "friendly" sessions with LT1 Vettes, LS1 Camaros, Firebirds, 3rd Generation Rx-7's, 90-96 300ZX Twin Turbos, Stealth/Mitsu Twins, and of course the Supra Twin Turbo's, they all great cars in my opinion. :) But now that I have experienced all of them and owned 2 of them, and no longer own them, I miss my little red Porsche the most!
More to come! I promise!
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