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Round 3 of Supercharger Kits?
#1

The last kit from Round 2 has now been spoken for and will be shipped shortly. (The ad will come down very soon.)



That brings us to Batch 3. As you know, I have to make these in batches of 15 to keep the price where it is. I realize that not everybody is sitting on the cash right now. No worries. What I need to do is see if we are even going to do a third batch at all.



So, if you intend to be in on the next batch, I need to hear from you. A post here will be sufficient for now.



If enough people line up, then I can start taking deposits. I can do a layaway plan too, so that people can just start sending money and not worry about frittering it away and never getting to the kit.



Based on how long it took for the last kit to go, I expect this first process to take months, but it would be best to get on the list as soon as possible.



So, who is in?
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#2

i love the lay away plan.

<img src="/forum/images/smilies/968/clap.gif" class="smilie" alt="" />
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I love my 968 for what it is & don't hate it for what it isn't!
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#3

I am a candidate. Put me in the line up.
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#4

You should do a non-A/C version. Use a bracket like this:
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#5

the bracket is the easy part. the hard part is the tuning. i would need a car on which to tune, as the AC provides drag, even when off, which results in fueling and timing differences from a non-AC car. this isn't a big deal in a normally aspirated car, but it's huge on a supercharged one. the part throttle maps would all be different.
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#6

You are welcome to come over to london Flash and play with my non aircon car! If you ever have a non aircon solution then count me in, alas I reckon I may have to wait until round 33.........
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1994 968 Sport (UK Spec)
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#7

Flash is the master of the bracket. He does good work.
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#8

The Motronic has adjustment for idle (speed is increased to account for drag with AC on) with AC on or off, I didn't think there was adjustment in the PT maps for this. What is the difference between having an AC car with the AC turned off and one with no AC? The drag with AC off is miniscule and shouldn't matter. Porsche certainly didn't use different ECUs for non-AC cars.
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#9

there is drag of the compressor itself, even when the AC is off. it does matter, if you want it to run "right". if you don't care about throttle response, then go for it.



there are over 140 maps in the motronic for the 968. they all play in at different points on different cars. the US cars use one set, the ROW and non AC cars use another set, and the cat-delete cars use entirely different maps.



you cannot compare the normally aspirated maps to the supercharged maps either. boost changes everything. the response time of the motronic is slow enough that without the AC compressor, it would advance faster, meaning an increased chance of knock sensor engagement, as well as a leaner condition on tip in. i had to create and entirely new map to handle the part throttle/boost issue, and would have to adjust it for the load change.



the changes would not likely be huge, but i can tell you for certain that they would be there



anybody can bolt up a supercharger. the key is in the tuning, and it is extremely complicated and time consuming if you want to get it right. that is why i have not issued an AC delete version.



even an AC ROW car is proving to be more complicated than i thought. i have the first kit on one now, and it looks like we are having software compatibility issues. i'll know more in the next day or so.
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#10

I could be "tempted" to add my name to the list, BUT...

my wife found out about DaveN's story to his wife that the supercharger was a required "air cleaner", so I can't use that story to justify the expense! <img src="/forum/images/smilies/968/laugh.png" class="smilie" alt="" />
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#11

The S2 cars have a coding plug to select the map - either Japan/California, Cat or no Cat if I recall. I thought the 968 was a "world" car and they all had Cat converters and used the same maps - at least that is what I have read in books.



If you are changing the EPROM, then I don't follow what would be different between a ROW car and US car as the map tables will be replaced. Are you suggesting there is a coding plug used in some versions of the 968?
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#12

yeah - the programs are not the same. the differences aren't huge (except for the cat delete cars), but they are there. you'd be surprised.



there are 4 different ECUs used over the years, and the chips don't go back and forth. most of the cars had the latest ECU, but there are quite a few that didn't. i had to have code written to handle the early ECUs. apparently i am not done with that.



technically the maps are not replaced, but rather modified (and a new one that is added)



the difference is going to be the lack of load due to the absence of the AC compressor. that program will be different than for a car with a compressor, just as the programming would be different for a car with a light flywheel than it would be one with the standard flywheel. (i still have to send out a chip to somebody who has one of those)



the bottom line is that i will likely never be doing an AC delete version, even if i could figure out the belt length and pulley arrangement (since a replacement pulley would have to be stuck in there to take the place of the compressor) as i just don't have access to a car to tune it



i'm not all that sure i'll be doing any overseas kits anymore at all, AC or not, unless i can work out whatever problem we are having with the chip. granted it is an earlier ECU, but it should have worked and doesn't. film at 11 on that
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#13

Anything for the full blown race car yet?
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#14

never going to happen. way too many variables to tune for. the first thing that would have to happen is the motronic would need to be deleted and replaced with a standalone. that would open the door for larger injectors and higher boost. of course then you would need an intercooler.



without that, all you get is a chuggy mess of a car, and i'm not inclined to open the door for somebody to think that is ok on their street car or dual purpose car, and then take a black eye from the criticism that it doesn't run right on the street. i would rather have fewer people with kits, but all totally happy, than more kits and some problems.



i may decide in the future to sell the mounting kit and such, with no chip or supercharger, and no warranty whatsoever, and let people buy their own supercharger unit (since i modify mine for the kit and it limits boost). then they can finish the process on their own and get what they get. it will be a lot more expensive that way, but it would let people do what they wanted. i haven't decided about that yet though.
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#15

[quote name='flash' timestamp='1316049519' post='115446']



i'm not all that sure i'll be doing any overseas kits anymore at all

[/quote]



<img src="/forum/images/smilies/968/whine.gif" class="smilie" alt="" /> <img src="/forum/images/smilies/968/whine.gif" class="smilie" alt="" />
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1994 968 Sport (UK Spec)
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#16

i won't know until i know what the problem is with the kit we have overseas now. if i can resolve it, then fine. if i can't, then obviously this won't work. if i can't figure it out one way or the other, then i am moving to bora bora and going into business making little drink umbrellas
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#17

[quote name='flash' timestamp='1316049519' post='115446']



technically the maps are not replaced, but rather modified (and a new one that is added)



[/quote]



Why did you need to add a new map?
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#18

actually there is not only a new map, but also new code written in the base program. it was a very involved process, taking a lot of time, and a fair amount of money, to get right. you can't just run the motronic as it is if you want your engine to live.



the motronic automatically corrects the mixture back to stoich at most every 1/2 second, and often every 1/4 second. no matter how much fuel you throw at it with a rising rate regulator or whatever, it will bring it right back. in any of the maps other than WOT this is VERY dangerous. it is extremely easy to go on boost in a map other than WOT. at best this engages the knock sensors. at worst you will have detonation. we were able to trigger the knock counters quite easily when we were tuning the kit, before adding the new map.



the new map, and the new code written to tell the motronic to do something else, corrects that, and without causing other problems.
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#19

ok - i have started looking at an AC delete option. i have come up with a preliminary design for it. i know what to do to work out the load change issue for the tuning.



what i don't want to do is plug in the 1k resistor that the cat-delete cars run to disable the O2 sensor, because this causes all sorts of problems with the mixture, and makes the engine run way too rich. this would result in premature engine wear. it also screws around with the way it runs. there is a bit more throttle response power, but at the expense of some street drivability and any chance of passing emissions testing. it would also foul the OEM cat very quickly. it would require a complete retune to go back and back that fuel out again in the places i don't want it. also, there is no way to correct it at startup, as there is a block in the motronic code that prevents it, so that would still be a problem.



fortunately i have a map that can adjust for the lack of load of the AC compressor, so the throttle response can be managed.



i expect the assembly and chip that would allow for AC delete would be about $500, due largely to the low volume of units, but it would allow for a seamless installation.



as soon as i have 5 people who step up for an AC delete, i can justify the development and can knock this out.
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#20

[quote name='flash' timestamp='1316112243' post='115486']

i won't know until i know what the problem is with the kit we have overseas now. if i can resolve it, then fine. if i can't, then obviously this won't work. if i can't figure it out one way or the other, then i am moving to bora bora and going into business making little drink umbrellas

[/quote]



Since I already have a domestic Supercharger Kit, can I be the first to sign up for the D1R drink umbrellas? <img src="/forum/images/smilies/968/biggrin.png" class="smilie" alt="" />



Please pardon the interruption......
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1992 Slate Gray Coupe over Carrera Gray Full Leather interior....1 of 1

2006 Cayenne S Icelandic Silver Titanium Edition

2006 Cayman S Seal Gray over Black
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