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In this thread I will try to show what I have done with the rotrex superchargers on the K motors. I have being playing with the Rotrex on a stock K20Z1 for 4 or 5 years, and bought a Dynapack in December last year to do the development properly.

Long term I am building 89 x 90.7mm, 88 x 99mm, and 89 x 103mm K24 ERL blocks.
These will all have ported heads, and cam profiles I have been developing specially for the rotrex.

In my signature I will keep updating my current WHP and as I find the time I will build the jaydeequantum.com.au web site with plenty of photos of the builds.

With the C38-91 the %eff is pretty good, so I am quietly confident that it might be possible to give the turbos a run for their money, at <25psi boost anyway. I may even try 2x SC in series. We shall see.

c38 81 vc C3094 are dyno graphs of the engine as first run on the dyno compared to the current setup, with the bigger intercooler, 1 months dyno development tuning and bigger SC. This is now about the limit.
k20stock  c38 81vc3094.JPG

509 - 510 are 2 dyno runs with the 509 being the current tune with a C38-81.
k20stock509 - 510bhp  c38 81.JPG
I still have the RRC inlet manifold, 74mm throttle body, and a bigger SC to try. The supercharger was given to me to try by Tom at Bullet Cars, who are the Australian importers and they have been very supportive of all my development. I will try, but I am not thinking the gains will be much more that 15 - 30WHP.

Crankshaft BHP is approx 7 - 8% higher than my measurement of WHP on the hubs, so we are at about 550BHP at the crank. The SC rating is 630 less accessories and SC drive so its maxed out. The next one I am going to try is the C38-91 which is 11% bigger. It should be interesting......

our pump fuel is equivalent to USA 92 octane and I run water/methanol injection

Enjoy, Tomola's video of the Jaydee Ariel Atom 600, with 579WHP partially tuned.

and here is the dyno graph of the 579WHP partially tuned motor.


Even though the quality is not great here are some track testing videos.




And Winton in car video with Motec Data overlayed

This is a copy of the Poster from the final year presentation in November 2013,and I thought you guys might be interested. The K25 engine simulation specification was from late 2012 as our Twin Rotrex SC'ed K25 is now at mid 600's WHP but otherwise the information is fairly current.



Common Question's I get.....
JAYDEE im trying to connect my WG with 4 port solenoid but i have no idea where connect this pipe which is conected to boost source.
Check this out


Could You tell me where is connected Your????

thanks
Marcin
I would place the hose feeding the solenoid close to the Rotrex. This will give you the highest boost source and enable PID control software in your ECU to create the most accurate PWM. As it is before the IC the pressure will be 2-3 psi more and this means the lowest boost setting will be 2-3 psi less with the 4 port solenoid which will give more adjustment range.


Cheers Jeff
 

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Re: Jaydee's All Out Rotrex on K motors - down under

Nice Work jaydee.
I'm subscribed.
 

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Re: Jaydee's All Out Rotrex on K motors - down under

i kid u not if u want a nasty fast dd the this is the way to go.. i mean who really needs more the 500whp for a dd and im sure that there is alot less lag then with a turbo... dude bump for u and some sick number..

my question is what compression are u running?? and do u have numbers yet on the 103 strokeX89mm bore
 

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Discussion Starter #5
Re: Jaydee's All Out Rotrex on K motors - down under

my question is what compression are u running?? and do u have numbers yet on the 103 strokeX89mm bore
The 510WHP is on the bog stock K20Z1 with the stock PRC inlet and TB, but with my bolt ons. Its the Australian version and Honda rates the CR as 9.8/1. We will have to wait till march when I should have the 88x99mm together, and I will remove the stock 2000cc motor, and measure the CR. I am interested to see the bearings, bores, etc. after 5000klms of constant abuse. The motors showing no sign of breathing/fuming and does not use oil.

Next week I will swap to the new C38-91 without any other changes, other than tuning to the higher boost levels expected.

The 103mm stroke motor is 4 to 6 months away. It will make alot of torque, and give us the chance to try some big inlet manifolds.

What I should have said in the first post is its not just maximum WHP for me. Its how nice the motor is to drive in the car, how it likes to rev, how it matches the gearbox, throttle response,etc. I like the idea of the long stroke to help fill the cylinders in the midrange where boost is less on the Rotrex than turbos. But having said that, I do not want a big sudden torque rise which will cause traction problems. Time will tell what the best combination is.
 

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The Professional
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Re: Jaydee's All Out Rotrex on K motors - down under

huge fan of the rotrex. i already love this thread keep the updates comin!!!!
 

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Discussion Starter #7
Re: Jaydee's All Out Rotrex on K motors - down under

old intercooler with 50mm piping, C30-94 maxed to 385WHP, then larger SC C38-71 maxed out to 474WHP
intercooler1_resize.JPG

new larger intercooler under construction, reused an old air research core, bar and plate unit
IMGP0959_resize_resize.JPG

the finished larger intercooler with 3 inch piping, c38-71 maxed to 484WHP, then fitted C38-81 to 510WHP, outlet is 7 degs above ambient on the road (before the water/methanol injection nozzle). A 15 Seconds run on the dyno without the fan and you will burn your hand on the intercooler!
IMGP0967_resize.JPG
 

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Discussion Starter #9
Re: Jaydee's All Out Rotrex on K motors - down under

jaydee,have you seen my PM ? :eek:
sorry I missed it. Replied now. Cheers
 

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Re: Jaydee's All Out Rotrex on K motors - down under

well,let's talk about your Boost controler.

so,first,which solenoid do you use?Hondata,Perrin ... ?
does the system react very fast,because it will be very usefull for the 1st and 2nd gear :D

about the External Wastegate,do you use a TIAL 44mm?
where do you locate it on the piping?

when it's opened,does it disturb KPRO or not?

do you have some pics too? :silly:

with this system,is it possible to make,like on turbo car,a "mode A" and "mode B" : i explain,the rotrex unit can deliver for example 16Psi at max of boost!so,the "mode A" for 10Psi so,with the WG opened for a long time.
and "mode B" with full boost
:confused:
 

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Re: Jaydee's All Out Rotrex on K motors - down under

looks like this thread is goin to be very interesting.:up:
 

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IMAKEBOOSTATIDLE
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Re: Jaydee's All Out Rotrex on K motors - down under

wish you had a dynojet to compare the numbers to


its a tuning tool who really cares. i bet it goes down the track faster then your car :p
 

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Discussion Starter #14
Re: Jaydee's All Out Rotrex on K motors - down under

well,let's talk about your Boost controler.

so,first,which solenoid do you use?Hondata,Perrin ... ?
does the system react very fast,because it will be very usefull for the 1st and 2nd gear :D

about the External Wastegate,do you use a TIAL 44mm?
where do you locate it on the piping?
You have opened up on some tricky stuff. :)
I started with the Hondata/Motec unit as its the same valve. It did work ok, but I was having problems as the %pulse width v's boost aim was hard to setup. At the time I only had a tial 38mm wastegate, so this might have been part of the problem. I could only get about 10psi boost control range. I would recommend the 44mm as a minimum. 50mm + would be good, so the PW is short from the ECU. I now use the Autronic valve, which is much better.

How fast it reacts depends on your attention to the piping and the valve. As the air control lines need to fill to the solenoid, after the solenoid and then to the wastegate under the diaphram, you need to keep all this to a minimum.

You are worried about boost control in 1st, 2nd. Since fitting the Rotrex I have never used 1st, even parking. Your car would be most likely the same as you get 0.5psi off idle, which makes the VE% of the motor on the mild cams really nice. I would expect you to take off in 2nd if you are going quick. The boost climbs pretty close with RPM, and so does torque, so she will spin in the upper RPM if its going too. By this time you have more road speed and more grip, so you can either short shift to avoid it, or use boost control to "limit" the top end boost in the low gears. I have gone a different route now, using an Autronic SM4, and have full TC, but I still need the boost control as its much easier to program when you don't have to cut 300bhp....:D

By the way, backing off the throttle but still revving it out does not work, as the VE% of the motor might only change by a few %. I have noticed on the logging maybe 10% loss in accel G, at 50% Throttle with the stock 60mm TB.

I fitted the Tial on the intercooler to the TB pipe. My reasoning was to keep the flow happening thru the intercooler to get better throttle transient response. My response is instant, even on the data logging at 100/sec.


when it's opened,does it disturb KPRO or not?

do you have some pics too? :silly:

with this system,is it possible to make,like on turbo car,a "mode A" and "mode B" : i explain,the rotrex unit can deliver for example 16Psi at max of boost!so,the "mode A" for 10Psi so,with the WG opened for a long time.
and "mode B" with full boost
:confused:
The boost control solenoid is just capping the boost to your desired value. You will need to map the Kpro at these load sites, so its alot like a turbo tune.

Most ECU's allow different boost levels to be setup, including the KPro. You will need to calibrate pulse width(PW) v's the "boost cap it gives", and then you can do as you are suggesting, with different modes for different gears.

I haven't taken specific pics, but in the "new larger intercooler under construction" in a previous post you can just see the red Tial wastegate.
 

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Re: Jaydee's All Out Rotrex on K motors - down under

Hey Jeff - I like what I'm reading/seeing... You should post the boost curve for the two graphs in your first post. When you say maxing out you mean @ 90k rpm impeller speeds on the rotrex units?

I'll be down at Calder on Australia Day..... track testing..... :up:
 

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Discussion Starter #17
Water/Methanol

What water methanol kit did you use?
Snow Performance stage 2, with the safe injection module added. Water/Methanol is 50/50.

I monitor the water/methanol flow from the safe injection unit as an input to the ECU, and adjust the timing as necessary. This makes an aggressive tune safe. I have not got around to it, but I could drive the pump with a PW from a 3D table using the SM4 ECU as control. This would save having to buy the full kit with the controller. I will do this eventually, as it saves money and its 1 less thing to go wrong.
 

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Re: Jaydee's All Out Rotrex on K motors - down under

What fuel do you run? 93octane?
 

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IMAKEBOOSTATIDLE
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Re: Jaydee's All Out Rotrex on K motors - down under

how many psi were you pushing with the c38-81 ?
 
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