boost pattern - video
 

Hi everyone,

Last days I am noticing a weird boost pattern/transition. The primary turbocharger boosts OK (10psi), but the transition isn’t so noticeable… boost drop for instance to 9psi, but when the secondary turbocharger kicks in the boost go beyond 10psi (around 11psi) but after 200-500rpms drops down to 10psi and stays dead on. I also notice that when I am off the throttle in the second turbocharger region (5000rpm +) and then back on WOT the pressure rises beyond 10psi and then drop down.

I have a stock 99´ Rx7 with no modification. Before that I didn’t have a boost pattern issue so now I am asking you, if this is normal or it indicates that something will go bad soon. I also attacked video... sorry because video isn’t so good.

http://www.youtube.com/watch?v=-qzji1Wm_bg

http://www.youtube.com/user/accrx7#p/a/u/1/saE00LCj7Xo

Thanks!

I wouldn't worry about it just yet...

:nod: It goes like crazy... you can feel that boosts a little bit more.

You might want to get an aftermarket boost gauge to see whats going on.

That factory gauge is hooked to the factory Denso MAP sensor, I bet it's pretty accurate. The factory boost gauges on the 2nd gens aren't bad, they just max out at 400 mm Hg or 8psi.

The boost may just fluctuate a little bit with the weather. Was it unusually cold outside?

The later model FD's had a slight increase in stock boost (11 PSI) which is what helped get to that 280 HP rating. Seeing above 10 PSI should be normal for a 1999 FD3S. You shouldn't see more than 11 PSI.

Seems normal to me(for a stock fd).

Thank guys! It was a little bit cold/fresh... I will wait for the warmer days and see what happens then. I am also thinking to buy a boost controler.