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DR,
It's great news to hear that you will be moving forward with your SC kits. I have an old Andy Keel Autorotor kit sitting on the shelf here. Would it be possible to use that as a base and buy the parts that you have improved (both cosmetically and functionally) or are they too different?
Hi Gary,
Intially the VERY patient people (talk about an understantment) on the waiting list have first dibs on getting "Tuner Kits" at this time. As long as they have been waiting I can't/won't do it any other way.
I have a limited number of SC units, fully machined intakes, etc in stock, so I couldn't immediately supply even partial components to those not on that long list.
BUT, when I get another run of intakes machined, I am planning to have extras just for guys like you that want them.
Currently I also have a supply of cast intakes that haven't been machined yet. I could make you a deal on one of those and you can get your local machine shop to do the finish machine work on them to however you want them for your application.
I am in-between Machine shops here that can do that for me, I just recently found out that my main Machine Shop (Toolcraft) that did them for me has gone belly up. So all the custom fixtures and setup stuff I paid them for has been lost ...or most likely tossed...as the company had been auctioned off in pieces before I knew about it....GRRRR.
BUT, I have been talking to a couple new ones, and want to talk to another one. Two of the ones I have in mind would be a blessing if I can get them to do the machining for me. Makes life simplier for projects like mine when the machinest also knows 928s extensively...it will also make it MUCH faster to get all the setup/fixtures back up and running :-) Fingers Crossed.
Some of the components I have fairly large quantities of, at least 100 SharkCharger and BlackBird Filters are in stock sealed up in boxes ready to go, plus a few other components that made the most sense to be made in quantity.
After SITM, feel free to give me a call and we can talk about anything I may be able to help you with. Or, if you are coming to SITM, snag me there.
I also still have a stack of my improved cast version of Andy's older intake uppers....for cheap. They are unmachined, have added enforcements to make them stiffer and solve the flex of those older thin lower castings etc and can be machined to work with any of the SC units.
I also have the old casting patterns for those (upper and lower) that I had modified for all the changes I made. So if someone needs them to make a replacement of those older systems I can get them done. BUT, you would be better off with my with completely original Series II castings, whole nuther beast :-)
__________________
David Roberts
2010 Jaguar XKR Coupe - 510HP Stock - Liquid Silver Metallic
928 Owners Club Co-Founder
Rennlist 928 Forum Main Sponsor www.928gt.com
DR,
Thanks for the reply. I would be happy to be added to the bottom of your waiting list (no rush on my end). However, I'll touch base with you after SITM to discuss what options I might have.
DR,
Thanks for the reply. I would be happy to be added to the bottom of your waiting list (no rush on my end). However, I'll touch base with you after SITM to discuss what options I might have.
Relatively new to this forum and to its history, it is quickly becoming very clear to me why you have such a loyal following. I sincerely hope your health continues to improve and I selfishly can have access to your thoughts on things 928.
Originally Posted by DR
This is pretty easy, and you have some excellent options for 928s.
FWIW, here would be my recommendations, based on a "little" experience and first hand knowledge of the various systems... and you should have no worries of making a mistake.
For 78-86 16V 928s -
Carl at 928 Motorsports www.928motorsports.com is the one to use, he has them well sorted, they work as advertized, and he will stand behind them and give you all the support you will ever need. Carl is the Man when it comes to Supercharging 16V 928s.
While not advertised (for fear of being lynched by some very patience 32V 928ers :-) 928 Specialists www.928gt.com has a 16V Twin Screw system designed for L-Jetronic/LH 16v engines (non-CIS). It is only in prototype stages as far as building parts, but if someone want to put one together I can supply the main parts for them to do it. These would be a DIY type build it yourself "Tuner Kit" for those that know what they are doing and can sort out the tuning/injection "details". The exception being the 84-86 Euro S 16V, of which I can get you 90-95% there and the rest is up to you. Due to the nature of the cost of one off type prototype parts (waterjetting 1.5" thick aluminum gets expensive vs cast intakes). It would be the most costly of the 16V options available. and will require the most "tinkering" to get it up and running perfectly (again excluding the LH Euro 16v). I can offer basic support and guidelines to make it work, but nothing like the real support for a production system until it is released as a production Kit.
But, keeping it real for the average 16ver wanting Boost... call Carl at 928 Motorsports, currently he is the real choice for that.
For 85-86 32V 928S
Tim Murphy - http://www.murf928.com/ has done a few of these and from what I have seen heard they are just as Rock solid as his 87-up Sytems (see below). Build Quality, Performance and Support are second to none, no surprises , no worries.
Carl at 928 Motorsports www.928motorsports.com also has a Kit for the 85-86 (Carl Correct me If I am wrong please) and while I haven't seen one in person, as with his 16V SC systems, you will get all the Performance and Support you expect and deserve.
David (me) at 928 Specialists www.928gt.com - Complete Twin Screw Kit for 85-86 32V 928s. Requires Tons of patience to wait for one, due to mostly my health issues..BUT things in that area are hopefully getting better very soon as I have already started building systems since getting back to work recently. Again if you are in a hurry, see Tim or Carl above.
For 87-95 32V 928 S4/GT/GTS
Tim Murphy - http://www.murf928.com/ is the SuperCharger KING of the late Model 928. There are more "Murf" SC kits out there running and kicking Butt than all the other options combined. Build Quality, Performance and Support are second to none, no surprises , no worries. ...Recommended you buy stock in Tire Companies.
Carl at 928 Motorsports www.928motorsports.com Until Recently Carl sold and supported the Murf Kit, but has recently created his own 87-95 SC Kit uising a Raptor SC. Again, while I haven't seen one in person, as with his 16V SC systems, you will get all the Performance and Support you expect and deserve. Carl knows Supercharging 928s as well or better than anyone.
David (me) at 928 Specialists www.928gt.com - Complete Twin Screw Kit for 87-95 32V 928s. Once again, requires Tons of patience to wait for one, due to mostly my health issues..BUT things in that area are hopefully getting better very soon as I have already started building systems since getting back to work recently.
We have also just started to sell "Tuner Versions" where we supply 95-100% of the components and the Tuner does all the assembly and some fabrication that I have been unable to do lately. Typically our Twin Screw Kits are shipped Completely assembled as basically a drop in intake assembly, similar to RnR refesh of a Stock Intake(but easier in some ways).
BUT, again if you are in a hurry for a 100% Ready to Install Kit, see Tim or Carl above.
Tim , Carl, please correct me if I got anything wrong.
A click on that link will tell you a LOT about our supercharger offerings. Our installation manuals are also downloadable (the first half) so you can judge whether they are well written, easy to follow, and whether you can install your kit yourself.
My 1990 S4 has a murf 3 and on the way to the DYNO the driveshaft broke. Wow, Hope the new shaft rated for 600 hp can take it.
Mac
Hi Mac,
I have seen you post that a few times lately. Not that it matters, but IMHO, your shaft was already damaged/weakened from a prior issue and was going to fail anyway. It is fairly common that the later 32V autos can damage or break the shafts. There was a TSB concerning this, see pasted TSB Info below
Murf's Kit just made sure you were aware of the pending issue...SOONER. :-)
This is typical when adding more power via Boost or however, if there is a weaken part in the engine or drivetrain, adding more power will not necessarily cause a failure, just make it surface sooner then it would have...normally.
TSB Broken Central Tube Shaft Vehicles With A/T
9228porsche01
July 7, 1992
Model 928 S4
Group 3
Part Identifier 3903
Number 9206
Subject: Broken Central Tube Shaft Vehicles with Automatic Transmission
ATTENTION: Service Manager/Service Technician
Models Affected: 928 S4 Model Year 1989 to 1991
Concern: Activation of the ignition monitoring system (injection circuit switched off fault codes 1131 or 1231) can lead to breakage of the central tube drive shaft.
General Information: Oscillations in the central tube system that occur when the ignition monitoring system has switched (flywheel effect) can lead to breakage of the central tube drive shaft. This can occur only in vehicles with automatic transmission where the vehicle is operated at an engine speed of approximately 1000 RPM. Possible causes are:
- Damaged or defective exhaust gas temperature sensors.
- Possible damage to the ignition coil wire left side (in driving
direction) between the ignition coil and distributor cap.
- Poor grounding of the mounting plate for the ignition final stages.
- Poor physical connection of the electrical plugs on the ignition final stages.
Parts Information: A new version temperature sensor, central tube and coil wire are installed in production.
Temperature sensor, Part Number 928 606 155 02 Central tube with changed material for drive shaft, Part Number 960 421
012 07
New coil wire with hose covering (for left side), Part Number 928 602 040 01
Repair Information:
1. If the central tube drive shaft is broken, replace the central tube with the new version part (see parts information). Refer to Technical Bulletin Group 3, Number 9203, dated May 5, 1992 for hints on central tube installation.
2. Replace the left side ignition coil wire with the part number listed in this bulletin. Be certain the coil wire is routed freely and not under tension.
3. Check all ignition components and connectors for corrosion, tightness, correct connection and damage. Repair or replace as necessary. If an ignition circuit has malfunctioned, an LED indication will be given by the ignition monitor relay located on the L-H control unit mounting plate.
Ignition circuit I (cyl. 1-7-6-4) Red diode Ignition circuit II (cyl. 3-2-5-8) Green diode
4. Replace both temperature sensors located in the exhaust ports:
Model '89-'90, cyl. 4 and 8
Model '91 cyl. 3 and 7
Use the new version temperature sensors listed in this bulletin.
The function of the ignition circuits and light diodes located in the ignition monitor relay remains unchanged. It is not possible to determine from the LED display of the ignition monitor relay if one or both temperature sensors are defective or which temperature sensor has failed.
When installing temperature sensors, coat the sensor adapter threads with molykote paste HTP (white) and torque sensors to 10 N-m.
5. After the temperature sensors are installed, the voltage difference of the sensors must be checked in order to ensure proper operation of the ignition monitor system.
Checking sensor voltage difference:
- Start engine and bring to operating temperature.
- Loosen the mounting bolt for the ignition monitor relay and pivot the relay up to gain access to the plug terminals Do not disconnect the relay plug.
- Set volt meter to the millivolt range and connect leads between E1 and
E2 of ignition monitor relay (Figure 3, white wires). A digital volt meter must be used. Polarity is not important.
- Measure voltage with the engine idling and again at approximately 2000 RPM. A maximum difference of +2.5 mV or -2.5 mV (depending on polarity) is permitted. If the voltage difference is above 2.5 mV, stop the engine, loosen and rotate one temperature sensor. Retighten sensor and check voltage difference. If the difference is above 2.5 mV, stop the engine and rotate the other sensor. If after rotating the sensors to different positions, the voltage difference is too high (above 2.5 mV) the temperature sensors are defective and must be replaced.
Its so great to see DR posting about producing more versions of his supercharger. It is especially great to hear that maybe some of the healthissues that have been slowing you down may be getting better.
The 928 community will be much better off with DR back at 100%.
Also, the response by DR on which supercharger to use showed great class. Too often these questions lead to bickering about whose interpretation of adding boost is "best". So, it takes a great deal of class to step back and post about the positive attributes of a competitors product. I have been saving for a supercharger for the last couple of years and the DR twinscrew will be getting a very close look.
Can anyone give me an rough idea how much a Murf928 "Stage 1" kit would cost (Who distributes in EU?) and how many working hours it would require to install onto an S4/MY88? WHat is the difference in terms of performance? Is there any overall reliability and robustness difference between a Stage III and a Stage 1 kit considering a normal road use (no race, no track). What else should be changed besides what the kit provides? Would an x-pipe be needed too? Can the A/C be kept with the Stage 1 and Stage III SC?
Wow talk about a blast from the past. Yes some great options and you can add one more to this ancient thread. I have had Victors Rotrex kit on for about 5 years now and it has been very reliable. You are lucky to have an S4 or newer because the kit is not for OB models. Relative ease to install and I know a lot of others have been very happy with the kit too. You can keep AC I believe with Murphs kit but not sure. Victors kit does not effect AC. Stock exhaust is fine but an X pipe is always a good idea. Yes noticiable difference for Stage 1 to Stage 3. More fuel and more blown air leads to more power. I suggest go big right away. As far as actual power increase, it is significant but I am not going to post any numbers for fear of starting the usual pissing matches that Supercharger treads usually lead too. Lets just say it will transform your car years ahead of this thread.
Murphy's kit does not effect the AC it stays as is working or not
I'd suggest Stage I to start out with, can always add Stage III (which requires an Intercooler).
A Stage I kit is maybe 8 to 16 hours of time to install depending on your skill set and tools.
Once you install an SC it's a slippery slope, and now you have a Porsche Hot Rod
All Hot Rod's require more attention to Details, it's all in the details on how reliable it will be. With that said if it's installed correctly and you keep up w/ maintenance it will be extremely reliable.
If your the type that never opens your hood to check on things, it won't be.
Thanks for your quick response and hints... I would not plan to install the kit by myself since I would not have the needed skills, nor tools or space. I would rely upon experienced generalist car repair shop located "round the corner" to my place who has been our family car repair shop for decades; he has been managing decently with my S4 too since I own it (7 years). He has both good electrical and mechanical skills and I believe he would not mind bothering a bit with this project, though he does not speak, nor read one word of english, therefore I would have to help him, at least with translating the instructions, which I hope to be detailed no matter the SC maker of choice. One info that you did not give, yet, is about the approximate cost; I could easily make up the labour, considering 16 hrs, but what would a Victors Rotrex, a Murph st. I and a st. III cost? I know I would need to add freight & duties unless any of them has representatives or distributors located in EU. I was considering to give up my two cats for an x-pipe already (since the car, german origins, once registered in Italy back 7 years ago, was rated as "Euro 0" for exhaust fumes.) and I thought of Ritech UK's one.
Once concern I have is about the "slippery slope" which DaveR talked about... how slippery??? WHat do you actully mean? My car has 120K miles (though the AT tranny I have gained some evidence that it was replaced some time ago...) How much would the SC stress the whole transmission more than std? Should an AT be more of a concern vs a MT with SC?
You would need to check pricing with the appropriate suppliers. It has been a long time since my install so I know prices have likely changed. I do know that the Rotrex kit is chosen by a lot of people for most bang for the buck and ease of install. With any system fuel mapping/tuning is important. I believe Victor can do some remote tuning with a laptop Sharktuner program but you will need to talk with him about that.