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Rotrex Supercharger thread

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Old 09-21-2012, 08:53 PM
  #16  
victor25
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Originally Posted by Cosmo Kramer
Did you have the 80mm pulley installed on your dyno pull? You said in the other thread that you let it go past 6 psi, how far past? Just curious to see what the Rotrex is putting down per psi vs us Vortech guys. I am sure it is more, but that 155 hp gain points to a minimum of 8 psi.
In the dyno chart above it was with the 75mm pulley, and non intercooled. With the 75mm it maxes out the MAF around 5000 rpms. That is why the kit comes with an 80mm pulley for stage 1. As you can see we stoped at around 6000 rpms, and yes it would keep climbing, if I kept going
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Old 09-21-2012, 09:11 PM
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Originally Posted by daveo90s4
Victor how do I find out more about this kit? Technical information. Installation issues. Whether it will fit on a RHD car (brake booster on RH side, etc. whether there is an IC option. Whether there is a lesser 5 psi pulley / boost option. How the air cleaner system works. What is done to prevent the maf boot coming off under boost. Whether a rrfp regulator is needed. That sort of stuff and more. Thanks Dave
Dave
Yes it will work with a RHD guaranteed!! if you only want 5psi then I would ship your head with a larger pulley. OH... speaking of that!! We sill soon have an adapter so you can change your pulley size at will. We can simply mount a permanent piece to the input shaft of your charger, and then you can change your pulley size at will by just removing a few alley bolts . Sizes will range from 70mm to 100mm.

The air filters are located in front of the radiator for fresh air. The kit will come with everything need in stage 1.

We have intercoolers ready... they mount directly on the MAF.

With 6lbs boost there is nothing special done to keep the MAF and boot together. The most important thing is to clean the maf and boot very very will when doing the install, and crank her down tight. I recommend roughing up the contact / clamping surface of the maf a bit with sand paper before clamping everything down. Having the BOV adjusted correctly is very improtant. It helps prevent your maf boot and silicones from blowing off when you let go of the throttle.

no rrfpr is need, as we are using 36 lb injectors and adjustable preprogramming PEM's

Last edited by victor25; 09-22-2012 at 09:12 PM. Reason: oops larger pulley, not smaller
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Old 09-21-2012, 09:38 PM
  #18  
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I saw on the other thread that this is for S4s; anything in the works for us 16v guys that love our cars?
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Old 09-21-2012, 09:46 PM
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Originally Posted by illini-heel
I saw on the other thread that this is for S4s; anything in the works for us 16v guys that love our cars?
Sorry nothing yet.... I do plan to adapt for the 85/86,. Problem with the earlier cars is that the crank pulley does not have a 6 rib serpentine drive on it. I believe that started in 84. Plus much tougher to tune.

I have not completely ruled it out, but nothing in the work right now.
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Old 09-21-2012, 09:53 PM
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Originally Posted by Jherriott
Isn't the boost constant with a supercharger as it is belt driven right off the crank? Shouldn't it feel like a NA motor with more displacement? Whereas a turbo has boost and lag issues because the time required to spin the turbo up only begins when you start to accelerate and gain positive manifold pressure?
Kinda mostly, but it depends on the compressor map as well.

Boost isnt equal at different mass air flows through it. Efficiency (temperature) results from the compressor vary depending on compressor design, and RPM.
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Old 09-21-2012, 09:56 PM
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Jon B.
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Originally Posted by victor25
c38-91
Thanks! I'm still looking forward to what you come up with for the S3 cars.
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Old 09-21-2012, 10:02 PM
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Note:

IC adaptation may be required if you have...*sigh*...Volvo motor mounts.

My IC is in interferrence with the supporting bow's for the transversal fuel lines at the top of the firewall.

It cant drop down on to the MAF boot.

I -did- have it on the car earlier, but once the MAF boot blew off, it was evident that my boot was not seated squarely onto the throttle body inlet, so the angle of insertion of the MAF with IC on it..wasnt very hopeful anymore.

My MAF was very tight to the IC, so they would not drop to the boot as a single unit. When I get back, will open up the IC fitting to the MAF a 'smidge' so that its not a press fit, and then fit the MAF, and then drop the IC on top of it separately, see where that gets me.

But with the Volvo MM's..the supporting bow's MAY cause you an issue, and MAY put the IC that last 1/4" too close to the hood.

Im not sayin, im just sayin.


Victor has been superb in his assistance to me. Im smart..I get it, but Im likely to ask a question before making uninformed opinions of what to do next if something comes up.

Someone buy him a non Sprint cell phone, please.
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Old 09-21-2012, 10:21 PM
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Nothing like calling someone on the East coast when it's 8:30 on the west coast LOL... Victor sounded kinda groggy when he answered ... or maybe it was Sprint

Originally Posted by Speedtoys
Note:
Victor has been superb in his assistance to me. Im smart..I get it, but Im likely to ask a question before making uninformed opinions of what to do next if something comes up.

Someone buy him a non Sprint cell phone, please.
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Old 09-21-2012, 10:26 PM
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Jeff

I am sure you will have no problem getting the IC on the MAF now that you have them as two sepperate items. I can tell you that it is a very tight fit even if you don't have Volvo motor mounts. Generally you need to have the MAF in place, then slide the intercooler down over the maf and seal it in.

And if you would quit calling me at 10pm "your time", it would be a hell of a lot easier to chat on my sprint phone..hahaha. But hey maybe you can set me up with something better during sharktoberfest. BUT I am Happy to help anytime!!!
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Old 09-21-2012, 10:26 PM
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Hello Victor.
Thanks for all your hard work.
I use an electromotive ECM, no MAF but a MAP.
I already have Carls larger fuel rails and an adjustable FPR

I would like some info on a chilled kit please.

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Old 09-21-2012, 10:34 PM
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Originally Posted by victor25
Sorry nothing yet.... I do plan to adapt for the 85/86,. Problem with the earlier cars is that the crank pulley does not have a 6 rib serpentine drive on it. I believe that started in 84. Plus much tougher to tune.

I have not completely ruled it out, but nothing in the work right now.
Thanks. Mine's an '84, no serp, multi-belts.
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Old 09-21-2012, 10:36 PM
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Originally Posted by 928mac
Hello Victor.
Thanks for all your hard work.
I use an electromotive ECM, no MAF but a MAP.
I already have Carls larger fuel rails and an adjustable FPR

I would like some info on a chilled kit please.
No worries, you will just have to do tuning on your own. Also the fuel rails your currently using are basically the same ones I used in the beginning before going back to the stock ones. Btw... the stock ones may not look as cool, but they hold more fuel volume and hold the injectors in place better... just saying. You can still use them you will just have to adjust the input location on the drivers side.

PM me if you want or get ahold of Mike about his possible group buy
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Old 09-21-2012, 10:37 PM
  #28  
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Originally Posted by illini-heel
Thanks. Mine's an '84, no serp, multi-belts.
yes but the alternator should have a 6 rib pulley
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Old 09-22-2012, 02:16 AM
  #29  
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Thanks for the info on centrifugal vs roots blowers Ted, didn't think about the physical differences making different power at different times. Make perfect sense.

Also, with the 928 having a rather cramped engine bay, I personally would like an inter-cooler, but do not want to cut 2 squares into my front nose... Has anyone tried using Lindsey Racings Thermal Hard Pipes? I wonder if they'd do the trick?
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Old 09-22-2012, 02:25 AM
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Originally Posted by Jherriott
Thanks for the info on centrifugal vs roots blowers Ted, didn't think about the physical differences making different power at different times. Make perfect sense.

Also, with the 928 having a rather cramped engine bay, I personally would like an inter-cooler, but do not want to cut 2 squares into my front nose... Has anyone tried using Lindsey Racings Thermal Hard Pipes? I wonder if they'd do the trick?

Then dont. Who said you had to?
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