does any mod...

[Ameer Antar]

your welcome...for one thing, a stiffer wg spring is part of any mod. 
Scott, owner of the SJM site has stiffer wg springs available in two 
different levels. Don't know what they are...

the problem is the R-Z mod is really a hack. On pre-'86 ECU's that's the 
only thing you can do b/c the chip is s'posed to be unprogrammable. But on 
your 200, there's no reason not go w/ a real chip mod. The difference 
between the hack and a chip mod is your engine's safety, esp. at 1.8-2.0 
bar. The R-Z mod just fools the ECU into thinking the pressure never goes 
beyond 1.4 bar. This is dangerous in itself, b/c you could easily get the 
turbo to overspin or raise the boost to dangerous levels beyond 2.0 bar. 
Although the actual pressure could be 1.6, 1.8 or even 2.2 bar, the ECU 
will never know. It will only see a constant 1.4 bar, until you go under 
1.4 bar. It's nice to have some sort of limit on boost thru the ECU and 
it's also nice to see the right boost on the stock gauge.

As you mentioned timing will be an issue b/c the timing map according to 
boost will remain the same from 1.4-infinity bar. The timing preset will be 
fixed at the 1.4 bar level. Timing will then be retarded by any increase in 
intake temp or knock. It's not as nice to rely on those factors to retard 
boost as changes can be drastic, causing poor performance, especially since 
knock retards all cylinders. Also there is some delay here and some limit 
to how much the timing can be retarded by knock sensor. By setting a timing 
entry in a mod'd ECU for 1.5, 1.6, etc. bar, you can preset a certain 
amount of retard avoiding any issues above. Basically, a chip mod is the 
safest and most elegant way to go. However, I have heard from listers that 
some chip mods are nothing but R-Z mods. Watch out for these guys. Scott of 
SJM does real chip mods as well as other sources. You should ask the list 
for reliable sources. good luck.

-ameer

At 03:11 PM 12/4/2000 , you wrote:
>Thanks for such comprehensive answer.
>Does it mean that RZ/stiffer_spring mod will not suffice to drive at
>1.8-2.0 bar because of lacking of additional timing entries?
>
>Ameer Antar wrote: