AFR Idea, need to know boost gauge voltage.
 

I am interested in change my stock boost gauge (bottom of the tach) into an AFR gauge. You can buy programmable O2 sensors that will give you the desired voltage but....What is the voltage range of the stock boost gauge?

C'mon 61 views so far and no one knows????????

My boost gage is mechanical not electric. Sorry.

Ask Mike. Mic on this board.

i dont think the gauge thats on the tach would respond fast enough

Thanks to all who responded...

Rarlyl8, Yes, I have a mechanical gauge as well and therefore I don't need the stock electrical one on the bottom of the Tach. That is why I would like to convert it to an AFR. This way I can see AFR while driving and have it match the analog motif of the car.

RG500930, can you elaborate on that concern?

This is purely my speculation for consideration.
The response time needed for an A/F gage is intantaneous. The response time for the stock analog tach is likely not that fast. The pointer mechanism probably cannot move as quickly as an LED lights up.

Re: AFR Idea, need to know boost gauge voltage.
 

I think that the factory boost gauge reads resistance, not voltage.

If you disconnect the boost gauge terminal completely, you get full-scale deflection (1 bar on a 930 gauge).

If you ground the boost gauge connection, the needle drops to zero.

The factory manuals give the resistance of the boost pressure sender as 5-13 Ohms at 20C (68F) at atmospheric.

Why not buy a 2 bar GM map sensor like they used on the Cyclone, and wire it up, and get the voltage from that... Quick, accurate, and voltages can be easily found...

Total cost - $60 - maybe....

BKS, I am confused. How is a MAP sensor going to provide me with AFR?

It doesn't.
seems, briankeithsmith didn't understand wat you are trying to do.

If previous poster is correct in stating resistance is used, than you wont be able to control the gauge by simply changing voltage output of WB controller. Unless, you can use change in voltage to change resistance...

Well, thanks for the information everyone. I guess this idea is shotdown.
1) the needle would be too slow anyway
2) WB sensors work on voltage and the stock boost guage works on resistance.

Time for me to move on to another crazy notion. :)

Have you seen these ?

http://www.3barracing.com/product_3.htm

No I hadn't seen them. I was just trying to replace my digital AFR head unit with something that looked cconsistent with the rest of the gauges in the car. I thought it would be cool if I could make use of the stock boost gauge that I am not using anymore.

Thanks anyway.

I agree.
I considered putting (hiding) those LED's in the demister vent, maybe the lights would bounce off the screen. Either way it is a discreet way of monitoring AFR for safety.
Somebody replaced the clock with the Innovate XD-16 gauge to try to appear stock.