Rotrex Supercharger & Engine Setup

As the boost comes up linearly on the supercharger a Map sensor is not really required. Just run off throttle position and tps. The stock map sensor only gets overloaded and caused intermittent spikes at the top end of the rev range. With Gen 2 you can run the |Ecu ed and a 3 bar map sensor I believe. Its another way to go on Gen 2 but not 1. The power is so smooth on gen 1 without the map sensor and with this off road application your not worried about the MIL light coming on (engine management light). 18lb of boost you will need bigger than 650cc injectors. But as you are not using the boost properly (not making much power from it as you have the ignition backed right out) it may be worth just welding in a pop off valve and setting it to blow off excess boost at the top end. I have a simple device I can sell you. That way the big blower will give you the low and mid boost with out over boosting top end. I will be doing this on my big build, just to try with a stock engine. I will post results in the next few weeks.

How to handle the original map sensor on a GEN1 ?
 
Just got off the phone with Hirsch Automotive, who makes an Alcohol proof sealer for gas tanks. They stated they have an ethanol storage tank with their sealer lined in it that has not broken down after 4 years! Sound like it would be perfect for my application..:beerchug: Still looking into E85 and so far the conversion makes a lot of sense for my application (cost benifit).
 
If I need to run an estimated 750cc or greater injectors with standard pump gas, that will need to be increased an estimated 30% for E85, will 975cc (750 * 1.3) or greater be too large to atomize fuel correctly? Although I was hoping not to, will I have to run secondaries instead? I just wanted to "drop in" larger injectors into the stock fuel rail but not sure if that's going to be ok.. According to one source, 1000cc will atomize great at idle meanwhile not be hard on fuel pump due to lower psi needed. Thanks!!
 
best thing to do with a supercharged application like this is to disconnect the sensor, its only used by the ecu at low throttle angles and at high throttle angle and boost it causes the ecu to spike and give missfires. If you disconnect it everything works very smoothly and the tps looks after everything, just add fuel. Using a Powercommander and big injectors causes problamatical starts, especially when hot. The Powercommander doesn't work when you first start the engine, for just afew seconds of cranking the ecu is throwing way to much fuel in, so you have to start with an open throttle to add air. It can foul the plugs. I now use the AEM FIC to fire a second bank of injectors and leave all the OE stuff alone. You can also retard the ign with the fic. It costs no more than a powercommander but does so much more. It also has its own built in map sensor so your mapping against boost not tps which will help turbo guys as well. Excellent piece of kit.
 
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Can I use the AEM F/IC to run primary injectors (somewhere around 1000cc with E85)and not use secondaries?? Trying to keep project within budget???
 
Yes it works both ways. Very good instuctions, comes with harness (not plug and play). check out AEMPOWER.Com. by the way I am not involved with AEM. I just like the product.
 
would a reflash be a decent remedy? as you'd be able to modify the idle tables to compensate for the larger injectors?
 
I have a 2006 ECU and wiring on 2001 motor (long story) so should I just reflash and not get a AEM F/IC??
From what I can understand
1. Reflash if you have a late gen1 and NOT running secondaries?
2. Use AEM F/IC if early gen1 and/or running secondaries?
 
I'm gonna watch this thread with interest...

I have Gen2 K8 Busa motor in a car that I'm thinking about supercharging (Rotrex C30-94) so looking to see what all needs doing really for a good reliable setup and good power. Driveability is more important to me than outright HP as I use it primarily for short sprint racing (low and mid range torque is the key for me on what I'd like to improve) so thinking about going the whole hog and rebuilding the engine properly for big power and reliability.

I'm not too knowledgeable on the eletronics side of things so will likely go for a stand alone management system that I can get someone that knows what they're doing set it up and map it for me. I've read before that you do and you don't need a map sensor for a SC so not sure which view to take! I do like the idea of 'flashing' the standard ECU but don't have a clue what 'flashing' means! I do have a couple of family members who are into their turbo'd Jap cars so I'm sure they could offer some help and advice on doing it...

Same issue with fuelling really. I already run an uprated HP pump, aeromotive regulator etc. I've been doing a little bit of digging and a fuel rail might have to be a purchase too? I'm not sure on injector size though and whether it applies to just primary's or secondary's or both?

On the engine side I'm a lot more comfortable, I like tinkering about with mechanical things. I'd like to give it an overbore to 1406cc (83mm bore) as well, new LC pistons to lower compression and some conrods for strength. I would seek advice on whether to lower it to 9.0:1 or 9.5:1. By doing this I take it that I wouldn't need a spacer plate? I guess it depends on what boost I want to run it I s'pose but thinking just now that I would like to build the engine to be able to run it at the max boost if I can. That likely means adjustable cam sprockets, new race cams the whole nine yards I think...

All theory just now though as I am quickly realising that the cost is gonna run into the thousands of dollars and I'm not sure if my hiding skills are good enough to keep the wife's suspicion low!!

Just realised I'm writing a novel! Sorry to hijack your thread! :whistle:
 
Great! Thanks!!! all of you... for the super helpful information... Defenantly wouldn't be able to take on this project without your valuable input... Long road ahead but.... I'm starting to see the light..
:cheerleader:
 
:please:Can anyone suggest a comprehensive software or spreadsheet that will help assist in setting up a high performance supercharged Hayabusa engine? I know some supercharger installers have software, but I have yet to find out who the software designer is and cost. Below is the link to best that I can find so far. It's a subscription and seems to be pretty comprehensive with plug-ins including E85 fuel etc. Any recommendations or thoughts would be greatly appreciated. Thanks!!
Supercharger Calculator version 3.2 | Supercharger Performance and Engine Performance Parts
 
When you say set it up, what do you mean? Setup is getting the ignitiona nd fuel right for the air going in. If you want a combo of parts to get a set bhp then with the supercharger its pretty easy but there are several routes to go. I.e. static compression, cam timing, boost pressure etc etc. i think we have talked but if you want to work it out for yourself then pay your $20 and see what it comes up with :)
 
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