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Rb30 Patrol


erall0
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hey guys I got a rb30 patrol with fuel injection im wondering what mods are required to get it to 180rwkw

the turbo I was going to use was going to be a t04e

will I need to lower my compression

also if I want lower compression can I just put in turbo pistons or do I need to change rods also

thanks guys

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Steve200b, have you got a dyno sheet to prove that?

I find it very hard to believe 160atwkw on 35's and a GQ drive line, and through a VL/r31 afm?

My GQ with a RB30DET @15psi just made 185atwkw on 33's and 4.88:1 diffs, pfc, 400cc inj and z32.

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hey guys I got a rb30 patrol with fuel injection im wondering what mods are required to get it to 180rwkw

the turbo I was going to use was going to be a t04e

will I need to lower my compression

also if I want lower compression can I just put in turbo pistons or do I need to change rods also

thanks guys

this isnt the 90's any more

just to clarify, t04e's are junk, and you dont need to lower your compression or open your engine to turbo an RB30e

best way to do it would be to wire in a cheap ecu like an adaptronic or something, hang a highflow hypergear off the side with all the supporting systems and then a decent tune

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Would you care to share the physical basis behind that claim? Where does the power go?

Well think of it like this, take out the small drive shaft, the r200 diff center, the little irs axles.

Put in a truck tail shaft @ twice the wieght, fit a 10.5" size diff center, fit axles twice the size and tires that each wiegh more than 2 of your original tire/rim combos together and tell me that wont sap hp?

Its very basic physics, E=mc2.

sounds stupid but its the more mass you try to accelerate, the energy required increases massively!

the next one is newtons laws of motion, every body acted upon by a force has a equal and opposite force acted back upon it, so the requirement to accelerate it is more so the heavier the object.

So this is where hp goes, through frictional loss, witch is a combination of windage, physical wieght, drag- from both wieght, size of components and material density.

It goes on and on the deeper you look into it!

The lhc in Europe uses maga watts of magnetic power to accelerate bits of particles to near light speed, if mass was easy to accelerate, theyd be sending house bricks around the tube wouldn't they?!!!!!

Edited by nicksamaniac
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Well think of it like this, take out the small drive shaft, the r200 diff center, the little irs axles.

Put in a truck tail shaft @ twice the wieght, fit a 10.5" size diff center, fit axles twice the size and tires that each wiegh more than 2 of your original tire/rim combos together and tell me that wont sap hp?

Its very basic physics, E=mc2.

sounds stupid but its the more mass you try to accelerate, the energy required increases massively!

the next one is newtons laws of motion, every body acted upon by a force has a equal and opposite force acted back upon it, so the requirement to accelerate it is more so the heavier the object.

So this is where hp goes, through frictional loss, witch is a combination of windage, physical wieght, drag- from both wieght, size of components and material density.

It goes on and on the deeper you look into it!

The lhc in Europe uses maga watts of magnetic power to accelerate bits of particles to near light speed, if mass was easy to accelerate, theyd be sending house bricks around the tube wouldn't they?!!!!!

Not true at all. Well, except perhaps the LHC bit.

There is SOME inertial effect from having heavier tailshaft, heavier gears, heavier axles etc. But it is very important to realise, especially with respect to the tailshaft and the axles, that the polar moment of inertia of those items is pretty bloody small, given that most of the mass is very close to the axis of rotation. Wheels, sure, they have a much higher polar moment of inertia, so making them larger and heavier will certainly increase their inertial effect on acceleration.

BUT, and this is a really big BUT, power output can be measured at a steady state. Acceleration only plays a part if you're running a ramp. So, if you were to take your engine, put it on an engine dyno and get the true power output of the engine, then install it into a car with skinny tailshaft etc and run it up to peak power and hold it there for say, 5 seconds, you should get almost exactly the same power reading as if you did the same thing with a bigger tailshaft, axles, etc.

You cannot argue against that. It is the absolute truth.

The single largest difference in power readings between engine dyno and chassis dyno in the power lost at the interface between the tyres and the rollers. Ignore hub dynos for the moment, because they throw a spanner in the works. We'll come back to them later.. Think about it. You have a 500HP engine in a car on a chassis dyno. You expect to lose 25-30% of that power when measuring it at the wheels, right? Where does that power go? I will tell you, it is most certainly not lost in the drivetrain. Some of it is, for sure. But if you think you can lose 125HP into the oil of the gearbox and the diff without that oil boiling in just a few seconds then you are severely mistaken. Furthermore, the amount of power lost through the drivetrain is probably not even a constant fraction anyway. There is almost certainly a minimum amount lost whenever the drivetrain is turning at speed, regardless of load, and there is probably a rapidly diminishing increase with load. This means that it starts at a non-zero number and increases with load but with the amount lost as load increases becoming a smaller and smaller fraction of the additional load.

Have you ever watched a seriously powerful car on a dyno pull? Ever noticed how much smoke and rubber dust is generated at the rollers? Ever wondered why you get higher readings if you strap the car down harder? It's because there is slip between the tyre and the roller. You lose a LOT of energy there. And the tyre and the roller are spinning around at very high speed in the air so they at least have some convective mechanism to shed that heat. The gearbox and the diff housing have almost no air flowing over them at all and so have almost no convective cooling. So if the 500Hp engine loses 125HP + on a chassis dyno, then I would say that more than 80% of that loss is at the rollers and only maybe 20% is in the drivetrain. So if you then beef up any part of the drivetrain so that it chews up more power, let's say you make it chew up 50% more than it used to - you are only increasing the measured loss at the treads from 125 HP to 137HP. Or, looking at the real drivetrain loss on its own, from 25 to 37 HP. Either way, it's not as damaging as you might have thought. But here's the best thing. Thicker tailshafts and axles and so on don't even have that effect. They don't lose any more power. They simply don't. They will certainly take a little off the acceleration because of added inertia, but as I explained above, that effect will be small.

The big wheels will certainly dull acceleration.....but again, they don't actually "lose" power. Measured at steady state (and ignoring compound/grip differences in whatever tyres you may have on different sized wheels) the power should be very close to the same.

Edited by GTSBoy
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Good argument, I still disagree with some of what youve said, most power runs I see have a ramp rate at witch power is measuered, nobody does a static power measurement at full rpm, full hp and full torque for 5 seconds!

Thats just stupid.

inertial wieght is ONLY low nearer the center of the shaft as it approaches zero rpm at the center even if surface speed is 100's of meter sec.

The only way id believe component size and wieght make no difference to hp output is at a static speed, but thats when load drops, torque becomes static and power drops off to a point where its only maintaining vehicle speed.

In any other scenario wieght WILL be a loss on the system.

If you take that 500hp engine and match it to a standard Nissan FS5R30A 5sp box, on the output in 4th (1:1) it makes, say? 490hp (for argument sake)

Now take that same engine, match it to a 15speed road-ranger transmission and same 1:1ish ratio, how much does it make now?

It can ONLY make the same at a static speed, BUT more torque will be required, more load will be applied and more hp will be needed to maintain the same static speed.

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And as a real world example, I took my patrol in stock trim for a power run so I had a starting point before all my engine mods.

It made a massive 75.3hp at the wheels on 28" tires, witch are like little chees cutter wheels.

the dyno operator said it was an expected result for the car type and showed me results from VL and r31 runs.

(same engine on a different drive line)

All of these figures where over 90hp, so how does a no loss idea explain a loss of 15hp?

And he also said it'll be lower due to, you guessed it, a bigger drive train!

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Yes they are, I can also confirm how crap they are, all companies make shitty choices, that is one Nissan made! Take a good solid engine and put a stone age fuel delivery system and ignition on it!

but mine was running efi.

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most power runs I see have a ramp rate at witch power is measuered, nobody does a static power measurement at full rpm, full hp and full torque for 5 seconds!

Yes, well. That's the difference between real power and measured power now, isn't it? Just because the dyno induces an error (ie, because of including inertial effects), doesn't mean that any power is actually lost in its journey from one end of a tailshaft to the other.

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