I did a day's worth of R&D for Forge on a Remapped MCC Smart, the best and most accurate way is to guage it up. I expect you can do that with VAG-Com which I guess you have access to.

You'll need to do some runs to establish your peak boost pressure with the standard valve and then do the runs with the Forge valve, making adjustments until you are happy.

Did you just buy the spring or the full kit?? Shims are included in the tuning kit. (PM me if you need one) You will probably only need a shim or two rather than another spring.

It's completely unique to your car when you have as many mods as yours, so you can get a rough idea from other peoples experiance but to tune it properly it needs to be done on your own car.

Now for the safety bit - I'm sure you know the risks involved with fitting a spring that is too strong, and it certainly won't increase your boost pressure.

It really is a game of trial and error.

Many thanks for your kind offer of a shim but I did buy the full tuning kit containing all four springs and shims.

I know about going too strong, I value my turbo too much for that!!

When I next get a free weekend I'll head up to a quiet road with my tuning kit and laptop for an extended play.

Just looking at the graphs again, looks like you peak at 20.2psi @ 4.2krpm with the OEM valve but it looks like it's fluttering a little at 2.5krpm through to 4.5krpm.

You peak at 19.3psi @ 4.1krpm with the Forge fitted, very briefly.

Did you notice that the boost pressure is in at a lower RPM with the Forge fitted. About 1670rpm vs 2050rpm

These things are sooo difficult to get right in 'on the road' conditions, so you have to try and make your comparisons with conditions as close to the same as possible.

Also you have 4 bar REVO in your sig - would that not be 1.4 bar?

20psi is 1.379bar and you appear to have about 20psi on the graphs.

Also you have 4 bar REVO in your sig - would that not be 1.4 bar?

20psi is 1.379bar and you appear to have about 20psi on the graphs.

Yes I have Revo 4bar which is just Revo's SW based on a 4bar FPR instead of the standard 3bar FPR.

In those boost runs I used an SPS3 and set the boost to High Boost 9 (maximum).

I have been thinking that the boost was on the low side but the car drives incredibly well.

It cant be a MAF problem as that seems to be fine

MAF log

Also you have 4 bar REVO in your sig - would that not be 1.4 bar?

20psi is 1.379bar and you appear to have about 20psi on the graphs.

4 bar is the fuel pressure regulator rating not the turbo pressure.

Ahh....

Told you hairdryers was my thing.

Yes I have Revo 4bar which is just Revo's SW based on a 4bar FPR instead of the standard 3bar FPR.

In those boost runs I used an SPS3 and set the boost to High Boost 9 (maximum).

I have been thinking that the boost was on the low side but the car drives incredibly well.

It cant be a MAF problem as that seems to be fine

MAF log

I am sure there are people out there far more qualified then me to help you out mate - I just read the graphs

:confused: I drove it today........was a bit rattly at 160 though. :sofahide:

The car that is

:eek: :eek: :eek: