I was in no way disparaging the top end gains, but more marveling over the low end gains. Even gaining only 30% up top, the gain across the rev range will make for one quick car. That's exactly the type of power curve I'm looking for.

 

Thanks mate. I wasn't so much taking it as a negative comment, but I felt I should give an explanation. There are some people around here who think I withold stuff. I reckon I'm being pretty open, without giving it all away!

Cheers,
Hymee.

PS - 30% up top would normally be considered pretty good for a "bolt on". The fact we get almost 50% at the bottom end is even better!

Cheers,
Hymee.

 

Thanks for sharing that graph Hymee -- sure is looking mighty nice compared to stock.

I find your thoughts on being able to tweak the upper RPM power exciting. Would you possibly accomplish this with PCM management adjusting, or pulley combinations ?

 

I'm thinking more in the intake someplace.

Cheers,
Hymee.

 

From my very in-experianced tuning mind, Wouldn't intake give you *too much* boost up top? if the supercharger can comress "X" Liters of air per "Y" RPM, with a linear volume/RPM equation, and the boost is constatnt from bottom to top, wouldn't that mean the engine is also properly moving all "X" Literes of air, from 0 - "Y" ? If the engine is able to Move all of that air, I would think that would point to *other* things, Spark, or timing? Maybe bad port timing? Maybe it is a combination problem: A lot of the mustang guys need to run significantly larger exhaust with a much larger throttle body when they upgrade superchargers....

 

By the way, just wanted to say that this is awesome work.. Can't wait to see the product that you are confident enough to atcually stamp some numbers on

 

dude, ur explanation of linear volume to rpm equation sounds like a centrifugal charger. I think thats what old mustangs use as well since they are small and easy to install.

And i think the larger exhaust and larger throttle is to minimise the restriction of the air flow (whether exhaust velocity or whatevea that needs to flow) so that they is less back pressure. I dont know, i guess thats what im presuming. I think backpressure means for restriction and hence less escapable chance and hence reducing power. I have no idea, just logically guessing here.

Maybe hymee meant that the intake could be set up so it takes up more air or boost at the top of the rpm. (is that right?)
And im assuming that as long as the fuel pump and injectors can handle it, it can be done without a problem.

My question is this hymee, since the renesis is a high compression engine (am i right?!? - please correct me if i am wrong), and i understand that high compression means that as boost increases to a certain point where the compression itself can cause the fuel and oxygen to ignite resulting in a 'detonation' or 'pinging or knocking'. I have no idea what its called.

I know its a common problem in a turbo instal, but since supercharger is based on the same princple of forcing air into the intake, does this problem happen in your car as well?

Im a lost case, so if you dont wanna explain to an idiot i understand.
Im just curious as hell!

 

Vito,

No problems with your q. Knocking is a problem with rotary engines, as well as piston engines. With appropriate engine management strategies and safety margins, the risk can be "managed". That is also why one might choose to run an intercooler - more insurance.

Cheers,
Hymee.

 

i thought engine management was supose to fis the air/fuel ratio and also fine tune the timing of ignition and also other things like disabling fuel cut-off at redline.

How does it control knocking? I thought it was just a result of pressure+fuel+oxygen = boom like in diseal engines.

Intercooler does explain it though, since colder air will be less subjected to high temperature which also induces knocking.

If i am wrong about the management system's role, please correct me, as i said earlier, im not a mechanic, just a curious little bugger.

I was thinking, what about a induction box which is long and flat to 'run across' the limited flat gaps in the front of the car. So that every air that manages to hit the front of the car is not wasted and directed directly into the air box or a compatment where the air filter is sitting. I think it actually might help since the air will be more readily avaliable and also be colder then a filter sitting where your filter sits. I dont know, maybe there is a better reason for your design. Just an idea out of the blue.

If you wanna hear some other wicked ideas from me just ask. See one other idea is a battery powered car, with batteries in the place where the fuel tank used to be. Since electric cars have problem with long distance driving and travel, a 'tracker-like' blades could be installed on the engine bay of the car and engineered so that when the air blows through, it spins the wheels which in turn charges the batteries or just runs the car it-self. (the blades will be horizonal like on a tractor and extremely light weight which will make the car nicely balanced with the light battery in the back.

See, i have these crazy ideas but have no where to release them.
Man, i get carried away when i express one of these useless thought dwelers) hehe
\
And what about a car that runs on a magnetic pulse instead of anthing else.
Electro-magnet on the bottom rails of the car, which alternate back and forth in the front and the back which makes them push and pull constantly with a weight on the bottom of the on a rail track which spins around controlling the momentum of the car. Does that make sence?. Its using the momentum induced by the weight's motion as it spins around the oval shaped rail on the bottom of the car. The electromagnetic pulses will be the source of the weight's motion. And as breaks use normal tyres but instead of using brake pads it uses eddy currents from the same electromagnet! YES, so the brake pads wont be worn out on easy cruise (but will be used upon application of the driver since the eddu current will only slow the car down thus allowing the control of the speed instead of actually stopping the car since it wont be able to)

Far out i got carried away again

sorry

 

Vito

Good start but you're getting waaaay

Maybe start your own thread with those ideas

 

Typically you would dyno in the 1:1 gear ratio on the transmission...

You would also need to take in to account the radius of the rim/tire since they give leverage from the axel and will change the final torq value. You'll also need to add in about +15% for drive line loss to get the final flywheel output.

 

That is ideal, as that is where the least losses occur, but is not normally practical. 9500 RPM in 5th gear of an RX-8 = waay to fast on the rollers. About 200km/h is about the normal limit for safety.

Nope - the torque value doesn't work like that. The force exerted would vary when measured at different radius.

Cheers,
Hymee.

 

Yep, that's what I was trying to say....

 

Hymee,

If you wanted, you could always jot down a few of the numbers, throw them into excel, and graph two curves (stock vs supercharge) with maybe 10 simple data points, then just post the graph without any numbers.

The screenshot image gets the point across though I think, but people love to see graphs.

 

!!! If that torque was the measured torque of the smaller diameter dyno roller, that would explain it's low value. Up it by the ratio of ( wheel dia. / roller dia. ) to get the torque of the rear wheels, then I'll bet that would give us something to look at.

Was that indeed the measured torque applied to the dyno roller?
What's that dyno's roller diameter?
haha!

 

It looks like the speeds at which the differents stages of te S-DAIS activates should be changed. Or at least one of them.

Fabrice

 

the last one the SSSV or whatever. itd be nice i think to stick it open for FI or open it earlier. sticking it open will cause a cel.

 

ello! ello! wots appened 'ere? wots appened to any updates?
(p.s. this is only my first post so dont slate me too much if i've missed something.)

 

We are waiting for " Hymee gets Supercharged (Part 3)"

 

Actually, "Part 1" was about sleep aponea and my CPAP machine.

 

ah firsky nufsky, looks like ill just have to get back to studying.

 

hey my dad has that he did some study with a doctor at hopkins that is trying to relate it to diabetes my dad was borderline diabetes before he got on the machine now he is completely normal the machine really works to keep you healthy in a lot of ways

 

Don't take Hymee's last post too seriously. It's actually from the Australian version of the SAT test:

CPAP: Nostril :: Forced Induction: ___________ (Answer: Intake manifold)

Its just some wacky Aussie humor brought on by too many boost spikes on his CPAP machine. Just be very glad that "supercharged" was not a Viagra reference.

 

Amazing you can sleep with that thing on. Probably worse for me considering that I like to sleep on my stomach. Good thing that I both don't have to and can't use one (fall in the small percentage that it makes things worse when used, but case is mild so not really necessary).

Anyway... glad you got treated. I imagine that it has made a dramatic change in your life. Finally getting diagnosed and treated for my sleeping disorders has changed my life like night and day.

 

<chirp> <chirp> Are those crickets I hear?

So whats going on w/ the super charger?