Hi Again,

Carl - you may have answered this already, so apologies if so.

My car definitely has NO dump valve. I was thinking the cheapest solution
would be to get a s/h forge atmos valve
and the rubber elbow from a car with a dump valve, and fit it in the
position the original goes?

Apart from the unideal position away from the TB, is there any big problem
doing this? I reckon I could reverse the
elbow and have the DV sticking out the front, should keep it a bit cooler?

Or, I could go to the hassle of removing the TB off an old engine I've got
about, using that with a recirc valve?

Opinions always wanted!

KR
Mike

in article 2nctbsFvov1eU1 (AT) uni-berlin (DOT) de, Mike P at privacy (AT) privacy (DOT) net wrote
on 04/08/2004 20:37:

Hi Mike,

I did this on my 900 T8: http://tinyurl.com/65voe

The throttle body is from a T16, although I don't know what year. If I were
to improve upon this, I would simply use a 90 degree reducing pipe (from SFS
Performance or Samco, et al) so the valve points forwards and is positioned
away from any wiring or other pipework.

I use the Forge FMDV004 (atmospheric) valve. I know of several others who
use this valve on T8s, T16s, T16S model and former LPT 900s. The dual piston
design gets around any "stalling" problems, but make sure you run a strong
enough spring. I use the blue spring (second strongest) in mine with boost
up to 0.9 bar. I tried out the yellow spring (second weakest) and got
variable top boost and some near-stalling when letting off from high boost.
The red spring (strongest) is definitely for higher boost applications (say
1 bar plus) and feels like not having a dump valve for normal driving. The
different coloured springs can be obtained from Forge as a "tuning kit" for
about 10 GBP.

Paul

1989 900 Turbo S
http://saab.go.dyndns.org/