Grainger Valve Shakes

I installed a Grainger valve in my '90 Daytona and the whole car gets the shakes when the boost gets to it's top level. If I take the G-Valve out, it runs normal.

Any ideas as to what is going on?

Do you have an Air/fuel gauge installed?

[89daytonaTII]

maybe the extra power makes your car shake. Is the g-valve set at the same psi as stock???

Yes I have an air/fuel gauge installed and I see little change with the addition of the G-Valve.

I set up my G-valve just as described in http://www.xmission.com/~dempsey/perform/grainger.htm.

Do I really need the small vent to atmosphere?

[guyd_15]

Yes!!!! If you don't have the vent to atmosphere, the boost signal to the wastegate actuater will keep the wastegate open. The restrictor vents this pressure signal to atmosphere when the boost level drops.
Guy Douglas

I didn't have a drill so I did my vent hole a different way.

I just put a T in the hose as close to the grainer as possible. A very small T. Works fine. I hope that fixes your problem.

I already have a vent right after the grainger valve.

Maybe it is just the waste gate trying to keep up and it cycles rapidily. I don't know but it is annoying.

[guyd_15]

"the whole car gets the shakes when the boost gets to it's top level"
I'm not sure what you mean by "top level" do you have a boost gauge? What pressure is it reading at "top level"? You may be hitting overboost, which gives a stuttering or shaking feeling.
Guy Douglas

[89daytonaTII]

when i hit overboost cutout, it feels like i'm hitting a wall, but i have heard that the earlier years were a little softer than my 89.

[ieatrice]

I'm having the same problem... and I'm not hitting "a wall" it just sputters and vibrates at max boost. My car's an 88. I've hit overboost many times when I first installed it, but now it just sputters. I can't go over 120km!!!

[SwiftTech]

Old cars hit overboost shut down hard too. my 84 has ripped several front mounts from hitting overboost unexpectidly. My car does a similar shudder on part throttle accel going down the freeway. @ aroung 5psi it shakes and hesitates, if I give it more throttle it smoothes out. I don't do much part throttle accel, WOT or brakes baby! So I really don't worry about it. Is you A/F guage showing Rich or Lean when when it does this? could be a lean miss fire? Clogged fuel filter? Fuel pump going out? Just an idea hope you figure it out.

[89DodgeSpirit]

just a thought - the added torque/power ... transmitted partially thru the motor mounts. I know that my car has bad mounts and if I go into any boost over like 3psi my loose door panels rattle and I can hear it - the whole car shudders a little albeit not violently.

I am willing to bet new motor mounts would alleviate most of this vibration/shuddering. Check your mounts - if they are bad replace them.

I recommend the Quickor urethane ones =)

[ieatrice]

For me, it feels like there's a leak or the fuel shut off or something. Not really a vibration, just rapid fluctuations in power.

[ieatrice]

Anyone?

[Lebaronguy2001]

replace fuel lines and filter?