2G power steering set up on your GVR4

[gtluke]

Quote:
Quote:
the p/s cut is a huge pain in the ass in an autocross or in the snow when you are revving the engine and trying to turn.





What happens if you were trying to turn while revving high then your power steering went out. Fried pump?



no, the mitsu design bypasses the pump at high rpm. it pretty much turns the pump off when it nears redline.
its not bad for the pump, just makes it hard to drive.

 

[curtis]

Damn you guys I can't get a break.... something else to address for me to mod. I do have a serpentine 2.5 subaru one in the garage that has a tank on top. /ubbthreads/images/graemlins/grin.gif

 

Quote:
i wonder how much power gain will the the 2g one makes due to the fact its a rib belt ( v belt robs power )
/ubbthreads/images/graemlins/devil.gif its free hp /ubbthreads/images/graemlins/devil.gif

Yes, but since the you need a different size belt and different pulleys you forgot to take pulley size into account. Now the pump maybe under-driven or over-driven, so he actually maybe losing HP, or gaining more HP than you'd expect.

 

[IncorpoRatedX]

i'll check the pulley size tomorrow you OCD freaks. /ubbthreads/images/graemlins/grin.gif

 

[mountaineerjeff]

what if used in conjuction with a 2g underdrive pulley? definent gain then.

 

[JSchleim18]

How to: click

 

[Dialcaliper]

The 2G pump is basically identical internally to the older version. The flow control valve is actually a 3-stage setup. It has two ranges where it decreases flow (sharply between 700-1000 to compensate for weak pump flow at low RPM and at a slower rate at 1000-3000). And the final stage above 3000 RPM where the assist is limited to a fixed size flow channel. You don't want to completely remove the spring - You'll end up with way too much power assist at freeway speeds (resulting in mushy steering feel). The result is a pretty linear pressure vs flow slope up to about 5500 RPM. The problem is that above that, flow drops off rapidly when the relief valve opens to prevent the pump from exploding.

The best result will probably be had by shimming the plunger to somewhere in the middle to end of the 1000-3000 range if you still want to retain some steering feel.

More info Here, page 19-11 if you're interested.

 

[belize1334]

This guy on Autocross.dsm.org seems to think that only 1G's had this issue. So, if the pumps are basically identical, then maybe there's something else that's different. Could it be that the 2G uses a bigger pully on the pump (or smaller pulley on the crank) so that it's not spinning so fast at 7k rpms? Even if that isn't the default case, maybe somebody could build/install an oversized pump pulley so that the pump is only spinning 80% as fast as in OE configuration. That'd make the cutout not happen until nearly 9k rpm which is higher than most autocross engine go.

 

[GreenGSX]

All you have to do is get your hands on a 1G NT power steering pump (mistu engine). I've had one on both my 1G track car and the One Lap VR4 and I don't have a hint of power steering cut-out even when autocrossing. Its a really old-school autocross mod I picked up from Mike at DSS.

 

^Yeah it has been on the vfaq for 11 years or so.

 

[JSchleim18]

Quoting GreenGSX:
All you have to do is get your hands on a 1G NT power steering pump (mistu engine). I've had one on both my 1G track car and the One Lap VR4 and I don't have a hint of power steering cut-out even when autocrossing. Its a really old-school autocross mod I picked up from Mike at DSS.



When you say a NT power steering pump, do you mean 2.0 or 1.8 or it doesn't matter?

VFAQ lists that the cutout is on both Turbo and Non-turbo 2.0 but says nothing about the 1.8?