Rb25det

[stranger12]

Guys

I have two questions and appreciate your input

Is boost relevant to hp?

For instance does all turbo at 10psi make the same hp? If no what is the impacting factor? Size of turbine?

Is there a formula to calculate at what boost turbo x will push the same hp as turbo y at given boost?

Second question is, if i tune my car to 500 flywheel or 400 rear wheel in hp, does it burn my standRd clutch straight away?

Is it because of extra force from flywheel which burns the surface? What i am trying to get to is, is it possible to change the turbo remap and then change clutch

[GTSBoy]

Why is this thread titled "RB25DET" if there is nothing in it that is about RB25DETs?
FFS!

But......

Is boost relevant to HP?  Of course it is.  Add boost to an engine (that still has capacity to handle it, ie, not on the edge of mechanical strength or of detonation, all the supporting systems have sufficient capacity, etc) and it will make more power.  Duh.

Do all turbos at 10 psi make the same power?  Hell no.  Of course not.  That is why there are small turbos and big turbos.  Small turbos pump less air than big turbos.  So a small turbo can boost a small engine to 10 psi and make what that engine can make at 10 psi, and a big turbo can boost a bigger engine to 10 psi and make what that engine can make on 10 psi (ie, more power).  And even on the same engine, a bigger turbo, with a bigger exhaust housing (and therefore a reduced back pressure imposed on the engine) will make more power at 10 psi than the small turbo will.

Will you burn your standard clutch at 400-500 rwHP immediately.  Yes, it will probably die on the dyno.  It will likely slip.

Have all these questions been asked before?  You bet your arse they have.

[stranger12]

thanks mate

 

is it the extra force excerted from flywheel which burns the clutch?

 

I am correct assuming if I was driving very easy then theoritically the clutch should still work even on 400 bhp at rear as the force against it has not increased?

Drive like a sunday drive

[GTSBoy]

Clutches work by friction.  They have a spring force F(n) pushing the plates together.  They have a certain area of plates touching and they have a friction material with a coefficient of friction, called "mu".

The amount of frictional force that the mating surfaces can create is defined by F(n) x mu.  This is therefore effectively fixed by the properties of the clutch material and the spring.  There are tweaks that the clutch designer can do to adjust this fundamental performance limit, but basically the formula gives the maximum amount of sideways (in this case it's a rotating sideways) force that can be transmitted by the clutch without slipping.  That sideways force is the torque that the engine develops.  Make more power, you make more torque.  If you make more torque than the clutch can transmit, then it WILL slip.  It might not want to hold as you engage it.  It might slip while it's already engaged and you give it a big throttle prod.  But it will slip.  And when it slips it overheats, damaging both the friction material and the cast iron bits.

So, no, the clutch will not work even on 400 HP at the rear.  You will not have 400 HP unless it is tuned, and you will not be able to tune it unless you have loaded it right up on the dyno and if you do that it will likely shit itself on the dyno.  You might get lucky and the clutch survives.....but the stock clutch is really not intended to take that much torque and will probably crap itself.  This is what I told you last time.  It will die on the dyno.

[stranger12]

makes sense

 

I was just trying to see the order of doing the work so will get clutch done prior to doing any engine work

[thebe]

Keep in mind you will also need to upgrade your fueling and your engines breathing when slapping a bigger turbo to rb25det (if you want more power). Bigger injectors, fuel pump, exhaust, intercooler & piping and so on. Along with the turbo, clutch and ecu/map. And a map is the last thing after you have everything else installed

[stranger12]

By fuelling you mean the pump?

[GTSBoy]

By fuelling he means the important things to do with fuel, being the pump, the power supply to the pump, the injectors.

[stranger12]

Cool thanks all under control now just buying stuff as i am typing ( walbro)