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Re: Maximum boost 1.3??

Chris :

I also have an 88 5KCS but Quattro 5speed, my max boost is also 1.3 as it
reads on the digital computer display of the dashboard....

keep in mind that 1.0 bar is atmospheric pressure so 1.3 is really .3 of
boost. Alot of people on the list understand this conservative boosting and
know that the 10v 2.3 can handle more boost....the ECU and the Wastegate are
the main reasons for the boost topping out at .3 ...at .3 the wastegate opens
and excess pressure is released....the ECU will also monitor RPM's in
conjunction with this and prevent overboost conditions.....

We both own a vintage of turbo which uses a "mechanical" wastegate which is
controlled by a spring, newer turbos (20v etc..) use electronic wastegates,
but anyways...

There are upgrades out there which replace the current spring in your
wastegate and also replace the "chip" inside the ECU these upgrades allow the
boost to build anywhere from .8 to 1.1 BAR which will push your dashboard
guage to read 1.8 or 2.1. Intended Acceleration sells a Stage I chip and
spring upgrade as do other vendors...my father has a 10v with the IA Stage I
upgrade and his guage gets to 1.8 on the dash ..there are many choices in
this upgrade arena...some folks have just tried the replacing the wastegate
spring and enjoyed the additional boost without changing the ECU...if you
want more details I can tell you in private e-mail but the IA upgrade or an
upgrade from Hoppen in FLA are in my opinion the best way to go....anyways
going from .3 boost to .8 boost is the equivalent of 50-60 HP gain so it
makes a big difference in power at boost.

2 more items ....1. many folks on this list with track/engineering experience
have Stage II upgrades and push boost well above 1.0 bar for your guage total
of 2.1 to 2.3 and the 10V engine handles it very well...and 88 Quattro set a
land record with Bobby Unser at the wheel at Talladega with a motor pushing
600HP imagine the boost on that beast...the record was an endurance record
proving the engine, and drivetrain capabilties.
2. Remember we are controlling max boost so turbo spool up or lag are not
improved simply more boost is retained in the engine....

Hope this clarifies, pardon some typos,

90 90
Rob Carselle - Columbus, OH