pormgb

Hi all, I have just finished supercharging my 1986 944 NA. I wanted to keep the cost down so I used a Paxton SN89 from a 5.0 mustang and made my own bracket for SC and alternator. The Paxton is not the best SC to use because it provides most of its boost at high RPM but it has served my purpose well and kept the cost down. My stock AFM has been replaced with a Ford Lightning 90mm racing MAF and fuel/air control achived by using a product from Zone 5 called the Mafterburner, the stage 1 Mafterburner has two maps that are controlled by WOT /TPS, because this product was made to work with a Ford PCM the WOT signals are inverted so the open-loop and closed-loop maps are inverted. Boost control is achieved with a Greddy type S BOV, I can adjust this BOV to release intake pressure and control boost. For fuel enrichment I purchased a EIP fmu (like Cartec) which can have its base pressured adjusted as well as rising rate, I would rather use a Bosch type adjustable FPR, I recently saw one on Ebay that was made by Huntley Racing. I also decided to use a stock 944 Turbo intercooler; my 86 already had the brackets so it bolted right in. I am also looking for a vented nose so I can increase the air flow to the intercooler, I currently have fabricated a channel that brings air from just below the bumper but the gap is very small and I don’t think I’m getting much air to the intercooler. The conversion went very well and was quite easy, I had to do allot of reading to understand how the 944’s DME/AFM works and how the vacuum system would react to boost (some trial and error), FR Wink’s web site really helped. I have almost got the car perfectly tuned; I drive the car around with the notebook adjusting the fuel/air map for the best performance. The car performs very well and I’m only getting between 3 and 4 pounds of boost, the Paxton can produce around 8 pounds but I have it loosely shimmed. Of the mark performance is much better it feels like it has much more torque, when you hit around 3000 rpm and the cam comes in, the SC really begins to work (big smile on my face), So far I have driven the car up to 5000 rpm and the SC is still pulling strong. I’m going to keep the boost low for a while so I can get the car perfectly tuned and not blow it up, I won’t increase boost until I can get more air to the intercooler. The reason for me writing this is that I love my 944 and am not in the position to buy a turbo, my 86 944 is a rear no sunroof model and has many of the normal luxuries deleted. I’m also restoring a 1965 Corvair Turbo which is also highly modified, the 944 conversion was really to prove It can be done and provide quite good results. I estimate the whole conversion cost me around $2k Canadian dollars but I think I could have done it for $300 to$ 400 less, this is because I bought a bad supercharger that I had to rebuild. I purchased all the intake components from Ebay and used generic 2 ½” and 3” aluminum pipe with intercooler couplers, the conversion also looks very professional and sounds great (Paxton SC Whine). By the way I wasn't able to keep my AC, I don't really care but I'm thinking of a way to get the compressor back installed. If any one is interested in this conversion please feel free to Email me, ill help as much as I can.

Techno Duck

I think i speak for everyone in saying we need more pictures, video and dyno numbers!

That looks freaken awsome! How much power to you estimate you are putting out now? How hard does it pull?

pormgb

I'm really at the beginning of this conversion and I don't have access to a dyno, I also want this car to pass its emission test so I have built it to utilize all the stock emission mechanisms (blue1/2” hoses ). The mid to high performance is impressive, I was quite surprised when I pulled past 3000 rpm and the road began to end quickly, I love the high to mid range pull of a 944. I'm not sure how accurate my boost gauge is but it registered around 4 pounds of boost. I have taken pictures of the complete installation and I will bring up a WEB site with them. With regard to hp, I'm probably seeing about 20% to 25% more hp, based on other conversions running much higher boost I believe SC can produce up to 50%, the is a 924s with a roots type SC producing around 220bhp.

To be honest the roots type SCs seem to have the best boost to rpm ration. I thought about using a M90 but I didn't fancy welding aluminum to build an intake similar to the one Huntley racing produced. There are also be better centrifugal SCs such as the Paxton Novi series and the ATI Procharger, I have to agree the SN series are quite small and can be mounted high on the motor, space is very limited in the 944s engine bay and you don’t have much hood clearance, I has do allot of measuring and clearance checking before building the bracket.

Techno Duck

Did you have to move the alternator? Looks like that SC is right over it.

I am very impressed with the work done. How long did it take you to finish it? I recommend cross posting this in the main 944/951...etc forum. You will defenetley catch alot more attention there. I look foward to seeing some videos of this if you get around to it!

My 944 'kinda' sounds like i have a supercharger....i just changed my timing and balance belt .

pormgb

Yes, the alternator has to be moved down but its really easy to make a bracket (1.5" thick aluminum plate shaped on a band saw), my SC bracket and alternator brackets are two separate pieces, I done it this way so I could achieve maximum adjustment. The second time around ill use a single bracket and mount the alternator a bit higher, I may even have space for the AC pump !!!!!. The hard bit is to get a workable template with all the correct dimensions. I would say the whole job took me two months, making the bracket and waiting for parts (Ebay) took the most time. I plan to be out tomorrow with my notebook trying to eliminate a slight hesitation at high rpm, I think it may be mixture related. One last note, the ICV and brake booster hoses are very important, these must be plumbed in between the MAF and SC (like stock position), my motor really behaved badly when I had these hoses incorrectly plumbed.

E-man930

Props to you for a nice SC conversion!

jgleano

SWEET.........

faceplate27

Why has nobody started making a kit for this? I would buy it in a second!

WesM951

That is sweet! I can't wait to see the kinda numbers it puts down. Mad props on doing it yourself.


People tried, they just couldn't sell them. Cost/performance ratio just isn't there.

JohanvdWalt

Dreaming of a SC myself but around here you just can't go without the aircon.

Very nice I'm jealous.

pormgb

Hi All,

I have recently done some more work on the car; I was really busy restoring my Corvair and really didn't have much time to finish my 944 project.

Since my last post I have added an oil cooler for the Paxton and completed my brake update (Turbo Brakes). I have also added rear coilovers with a Weltmeister
19mm rear sway bar. I decided to also change the wheels, I picked up a cheap set of 17” turbo twists, I also made a strut brace for the car.

The car runs really well and I have noticed a significant increase in very low end torque, I added a high output SC impeller which provides a few pounds of boost below 3k RPM. I still need to understand the art of determine the correct fuel air ratio, since I don’t have access to a dyno this has been a bit tricky. I really think the car can produce more power if I can get the right air fuel ratio, I recently changed the oxygen sensor and this really helped my idle.

I still have to find an air filter that work with the setup; I currently have a mesh between the MAF and the SC to keep stones out (stones in SC “not good”). My biggest problem is when I fabricate a filter the car will not run right, I haven’t figured out if its related to me not having a filter that flows enough to feed the SC or related to the affect of vacuum on the ICV, the ICV line is plumbed into the MAF that is on the intake side of the SC. Ill appreciate and ideas on how a higher level of vacuum can affect the ICV operation.

BMWM3PORSCHE944

Where is the air intake located?

pormgb

If you take a look at the picture you will see the black Ford MAF in front of the SC, at the moment there is no filter just the MAF opening.

BMWM3PORSCHE944

OK if I am looking at this correctly, I am seeing that the intake is located at the rear of the SC. Rather hot intake charge wouldnt you think? Of course it IS on the "cold" side of the engine, but man, that's gotta be a hot charge of air your getting. I imagine your not seeing that much of a gain in over all power as you are loosing an average of 30% engine power to the SC pulley, not to mention you are pulling in HOT air.

Not to mention the large crease in the piping going into the intake manifold. Unless you are inflating that thing, believe it or not that's gonna cost you a few HP.

Please don't get me wrong, I think you did an OUTstandign job on the whole thing. Im just trying to point out some weak areas that could cost you alot of power. There is more but Im kind of drunk and dont feel like typing anymore.

OH YEAH, if those are magnecore wires, ditch them and go with OEM. Much better.

Camaro_Muncher

AWESOME! I have been thinking of this for the past few months. How much more room could a centrifugal save? You should make a plan for the brackets. I have almost no knowledge on engine management systems, is there a good site where i could learn more? BTW dont listen to people who try
to stop you from this, I know the feeling of loving your car but wanting it to go faster.