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.

75ohm

Where's the Flux Capacitor?

If anything, that looks cool as hell dood.

joseph mitro

wow, great job. the installation looks nice from the photo. must have taken quite a bit of work to do it right, but props to you for doing so. it would be interesting to see what your rwhp and torque are now.

TRWright

I don't have time to read your entire post right now, but that is an awfully big SC!

It looks like you did a quality job though!

IMB951

WOW! That's a serious 944 motor right there. Looks great, nice and clean. That would be a reasonable alternative to the SFR setup if the power numbers come out right!

Everyone loves progress pictures if you have any!

nine-44

Looks like a nice install job man. I'm all for DIY(looks like you are also). I will suggest tho, the boost should be roughtly regulated by the pulley size. Normally on an install, you take the displacement per revolution and calculate it with the volume per revolution of the SC. Basicly the engine will move 625cc of air per revolution @ 14.7psi(atmosperic pressure from absolute) If the SC moves 1250cc of air per revolution at direct drive(1:1)done via gearing with the pulley then your absolute pressure will be 29.4 psi or 14.7 psi positive boost. Looks like you've done a bit of homework on this project so I'm guessing you've found a way to gear it or deal with this. I'm only wondering, if you set the peak boost with the BOV, it's "reading" the air comming in and adjusting the fuel accordingly. But, the extra air flow is being dumped after being metered. Did you just map it to compensate for this? Looks like fun man, I'm a project guy too. I also have an 86 non sunroof car, I love it! Just a thought, if that does prove to be a problem, I'd move the MAF to the boosted side of the system after the BOV. That should read actual airflow and be more precise after the excess is dumped. Looks sweet tho!

Mike B

Great job...Looks well done! Where in Canada are you?

pormgb

The boost is actually quite low because the Paxton is shimmed very loosely for a 4 cylinder motor. Paxton SN series SCs use pressure placed on 5 large ***** to drive the impeller. Because Paxtons are normally setup for V8 motors they are shimmed very tightly, if I increase the number of shims and tighten up the *****, the pulley will spin the impeller quicker and I will get more boot, this happens because the ***** don’t slip as much against the impeller drive shaft. I plan to reshim the SC after the car is running perfectly, I’m treating this setup with caution until I understand its potential.
With regards to the BOV blowing to the atmosphere, I have read that this setup can cause problems because the MAF still thinks the motor is receiving the same volume of air and passes the same amount of fuel to the motor, but the BOV has dumped the air (Rich). I’m not sure if I’m experiencing a problem, I haven’t notices any odd behavior when shifting. If I do develop a problem I can vent the BOV back into the intake (before the SC), if this happens at a specific RPM I can also set my map to adjust the fuel when the BOV opens. I tell you what, this is really a science, its really good to talk to some one who understands the science of boost!!!

Giantviper

WOW!!!! Great job man. Looks like you put alot of work an thought in to that. I would also love to hear what kind of rwhp and TQ your putting out.

Also for only 2 grand thats not bad at all, i think SFR's kit is at like 4 grand for the base one now. Also jsut curious how many hours did it take you to put together?

How well do u think the tranny will hold up, i here alot of people that do these such mods installat least a 951 tranny though a 6spd might be cool?

Lasty again great job man and cool project.

That thing must go like a bat ou tof hell.

pormgb

I'm located in the Oakville Ontario area; I want to show the car next year at the UCR Concours d'Eleganceat Appleby College. Where are you located?

pormgb

The car is still a 944 NA and my intention for the conversion was to bring a already good motor alive. I don't want excessive power that going to break other parts or the car, if I wanted lots and lots of power I would buy a 944 Turbo. The next thing on my list of upgrades is the brakes and suspension. I’m not going to spend a ton of money doing that, I have had six trouble free years of service from the car and since I do all the work my self I don’t mind spending some cash on upgrades. With regards to time, I spent around two months doing the conversion, out of the two months I spent around 5 full days and a couple of hours on some evenings.

nine-44

yeah, a metric ton of science and equal if not more luck, lol. On paper and real world don't always work proportionally. I've been planning that my lil project should do about 350-500hp. I came to the thought... OMG, it could be more than that, lol. I haven't done alot of homework on SCs (more of a turbo guy myself), I didn't know that the centrifugal chargers had a slip clutch type setup. Is it externally adjustable or does it require disassembly to adjust?

I did notice that I've tried 3 different BOV's(atmospheric venting) and the car hated every one of them. It would just act goofy on shifts, build boost differently with each one, etc. I'm running the bosch recirc valve and it runs the best. I'll probably go with a Stratmophere Hyperboost adjustable valve. It replaces the bosch style and is billet. That's on the "954"

If you have time to do a little reading, search for posts on project 949, that's the toy I'm working on now. Things have changed on the drawing boards a few times already and probably a few more times.

I would suggest to vent back to the intake system inside of the MAF, that would be best for your configuration. Should rule out any, going waay rich from the venting. I'd say with the way it's set up, you will find it easier to tune it in. Due to density from ambient temps, humidity, altitude, engine load,etc. It would be almost impossible to accurately calculate how much is being dumped. Good luck man, I wish I was as far as you are, lol.

emwporsche

does everyone with a supercharged 944 hate the enter button?

cool food dude

FRporscheman

What a beautifully clean engine! And that's a really fat SC. If you have time, before you forget, you should make a write-up.

Arash

NZ951

Awesome job, with the MAFterburner, did you have to do any special configuring? Was it plug and play? I guess I am asking what was needed to make it work...