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Supercharger advice request

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Old 07-24-2015 | 08:48 PM
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Default Supercharger advice request

My 89 GT has 70k miles and is well maintained. I store it indoors every winter and it goes from storage to the shop each spring to change fluids and whatever else is needed. I am not at all mechanically inclined and don't do any work on it myself. I put about 3500 miles on each summer just driving around town, no abuse.

I'd like to get a supercharger installed, maybe a 928 Motorsports Stage 1 or similar. Once installed, I'm not sure if the GT would require extra maintenance or tweaking during the season or if I can expect similar reliability as stock. Given my lack of mechanical skills, am I just asking for extra visits to the shop and frustration each summer if I get a supercharger? Or can you generally just enjoy them without too much worry assuming overall maintenance is performed every spring?

Advice on which system would be best for my car given my (light) driving habits also welcome.

Thanks for any thoughts - Mogans
Old 07-24-2015 | 08:50 PM
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Mogans...there are LOTS of threads on this subject. That sounds like an awesome 89 GT
Old 07-24-2015 | 09:26 PM
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The 928MS kit is excellent. If you can find a suitable pro to install it, and troubleshoot the initial install, including perhaps a tweak or two, you will arrive at a reliable vehicle with maintenance requirements similar to stock. You do need to accept a certain risk of adventure to arrive at something you will be happy with.
I was very happy with the 928MS kit and the tech support provided by Carl, the owner of the company.
Good luck,
Dave
Old 07-25-2015 | 09:05 AM
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Thanks for the responses. I'll post if I move forward with anything.
Mogans
Old 07-25-2015 | 11:52 AM
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Murf if you're going all-in and cost for system/install is no objective and max output is a factor.
Victor's if you are concerned about the value proposition, simplicity, think you might want to revert back occasionally.
Old 07-25-2015 | 12:28 PM
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Default The first thing to do

The first thing to do would be for you to sell the 89 GT and buy a cheaper 87 S4. 89 GT is more valuable in stock condition and the lower compression 87 S4 will make as much or more boosted power.
Old 07-25-2015 | 12:31 PM
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I would suggest whichever kit you go with, do a baseline dyno. Get your car up to what it should be before you add the SC.
With anything car, OEM will be your least work/maintenance. Adding a power adder such as a supercharger is not as simple as the vendors want people to think it is. Im learning as I go. I jumped in and bought a 928 with a SC on it. Smart move? Im not sure. I'm chasing low boost, and was chasing high A/F ratios. Im still sorting the details, but Carl is giving me support even though I am not the original purchaser.
Old 07-25-2015 | 02:31 PM
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Default Supercharger advice request

Originally Posted by ptuomov
The first thing to do would be for you to sell the 89 GT and buy a cheaper 87 S4. 89 GT is more valuable in stock condition and the lower compression 87 S4 will make as much or more boosted power.
+1

If the SC setup is properly engineered the maintenance will be same as stock except for the SC belt and SC oil if a sealed unit. If oiled via the engine feed, then just the belt, unless it's a serpentine system which is changed as part of regular maintenance.

The key is "properly engineered"

The MB, Mazda, Ford or other factory supercharged cars don't require significant additional maintenance.. My supercharged Range Rover is a prime example...

Best regards
Old 07-25-2015 | 04:14 PM
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Originally Posted by Darien Nunn
Mogans...there are LOTS of threads on this subject. That sounds like an awesome 89 GT
I'll be pretty happy if a roots option ever comes up for S3 again, at a decent price. I'm going to rationalize the expenditure just for recovered time/aggravation messing with the stock intake!
Old 07-27-2015 | 11:54 AM
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Mogans, we do also offer to install our kits if you want to send the car here. Customers ship them here, we do a baseline dyno, install the kit, tune it, and do an "after" dyno to confirm. Then we meet the customer at the Milwaukee airport with their own car, and they fly in and drive it home.

Or we can ship the kit, and the local mechanic or your self can install it,. the Stage 1 kit is pretty simple.
Old 07-29-2015 | 10:52 PM
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Carl, thanks for the information. I will get in touch towards the end of the summer. I'm in northern illinois, only a couple hours drive from you.
Old 07-29-2015 | 11:54 PM
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Originally Posted by Mogans
I'm in northern illinois
Mike Schmit (aka Z) Hacker-Pschorr and I have been talking about finding someone "local" to Green Bay to do another install weekend.

For references you can send a PM to Jim Roberts, owns possibly one of the cleanest GT's around. He drove it to from Long Island to Green bay, we installed the supercharger and he drove it home:
https://rennlist.com/forums/928-foru...emissions.html
He has driven it here 2-3 times since for various 928 gatherings.

Another reference is one of our moderators Gretch, a very early Murf928 customer:
https://rennlist.com/forums/928-foru...al-report.html

Gretch has a very early version of the Murf928 kit, dare I say version #1. The kit has come a long way since 2003


Last but not least, the tuning and fabrication.
Twin Turbo Todd did the prototyping work and is involved with every aspect of the Murf928 program:
https://rennlist.com/forums/928-foru...deo-added.html

Luke Stubbs, the owner of Beyond Redline does our tuning. To say he's good is an understatement. He's the man controlling the dyno and running the laptop when Todd's 1,000hp twin turbo 928 is on the drums:
http://beyondredline.com/

This thread covers the birth of the 85/86 kit when it was developed on Shane's car years ago:
https://rennlist.com/forums/928-foru...s-new-car.html

A local install in Green Bay will include a before dyno at Beyond Redline to record a baseline and make sure everything is operating as it should. Once the install is complete a custom tune on the same dyno with Luke Stubbs at the helm.

Please send any questions or comments at: info@murf928.com I'd be happy to setup a time on the phone to go over any details and arrange accommodations if you are interested in doing an install weekend.

-
Old 07-30-2015 | 12:02 AM
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Having installed, worked on, and seen most of the kits out there.
I would recommend the available SC kits in the following order,

Murf 928 SC http://murf928.com/
Then Victor's SC setup (don't know website).
I would not recommend any of the other "kits" available.

The nice thing about the Murf kit, is that it comes with chips designed specifically for the SC which adjust the fueling properly (instead of just raising the FP and essentially overclocking the fuel injectors). But the BIGGEST reason is that they also have an ignition chip which pulls out ignition timing as well!!!
The stock 928GT runs 30 deg of ignition advance at WOT near the top end. With 30 deg of advance the car already will see a few knock events (with all maintenance up to date). The maximum ignition timing that the stock setup can pull is 9 deg. This means that with pump gas, you will be detonating due to the higher dynamic CR of the engine once SCed.
Murf's chips follow the principles of Corky bell and pull out a deg of timing per pound of boost (give or take a deg or two). This ensures a safer running engine, which will last much longer. I do still recommend having someone who knows what they are doing confirm that the car is not detonating after the installation, but you are a million miles ahead right there.

As I said, my number 2 consideration would be the Victor kit. However this kit supplies PEMS requiring individual tuning of the car. This is a very tricky and time consuming job which is not up to my level of finess as it comes with the car. There are a couple other bugs which could be worked out making it my second choice of available kits.

The only thing which all the kits lack in my opinion is that the crankcase vapours are not dealt with to an acceptable level. But again, personal preference.

So the other kits which are available, yet that I have not stated, I would not use them as they do not properly correct the fueling, and more importantly, they rely 100% on the knock sensors to save your engine from catastrophic failure, after using a bandaid to get enough fuel into the engine.
Old 07-30-2015 | 09:03 AM
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One of these days I should get the Murph updates and install them.

My Kit and the car still runs like a swiss watch and pulls like a locomotive. Gretch is a Monster...... still.
Old 07-30-2015 | 10:46 AM
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Originally Posted by Lizard928
Having installed, worked on, and seen most of the kits out there.
I would recommend the available SC kits in the following order,

Murf 928 SC http://murf928.com/
Then Victor's SC setup (don't know website).
I would not recommend any of the other "kits" available.

The nice thing about the Murf kit, is that it comes with chips designed specifically for the SC which adjust the fueling properly (instead of just raising the FP and essentially overclocking the fuel injectors). But the BIGGEST reason is that they also have an ignition chip which pulls out ignition timing as well!!!
The stock 928GT runs 30 deg of ignition advance at WOT near the top end. With 30 deg of advance the car already will see a few knock events (with all maintenance up to date). The maximum ignition timing that the stock setup can pull is 9 deg. This means that with pump gas, you will be detonating due to the higher dynamic CR of the engine once SCed.
Murf's chips follow the principles of Corky bell and pull out a deg of timing per pound of boost (give or take a deg or two). This ensures a safer running engine, which will last much longer. I do still recommend having someone who knows what they are doing confirm that the car is not detonating after the installation, but you are a million miles ahead right there.

As I said, my number 2 consideration would be the Victor kit. However this kit supplies PEMS requiring individual tuning of the car. This is a very tricky and time consuming job which is not up to my level of finess as it comes with the car. There are a couple other bugs which could be worked out making it my second choice of available kits.

The only thing which all the kits lack in my opinion is that the crankcase vapours are not dealt with to an acceptable level. But again, personal preference.

So the other kits which are available, yet that I have not stated, I would not use them as they do not properly correct the fueling, and more importantly, they rely 100% on the knock sensors to save your engine from catastrophic failure, after using a bandaid to get enough fuel into the engine.

Colin has said it pefectly.


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