stoked944

When i buy the wastegate, what spring should i get? I'll be running a stock turbo k26/6 and maybe upgrading awhile later.

CPTdooberhead

I would get a one bar spring- thats what I got with my 46 Tial and im happy with it

Danno

Yeah, get at least the 1-bar spring. Somehow on our cars, if you hook up the banjo-bolt directly to the wastegate, you end up with a boost-level of 80-90% of the spring rating. So pick a spring that's about 10% stiffer than the target boost you want to run. So for 15psi max-boost, pick a 1.1-bar spring. This stiffer spring will help hold a flatter boost-curve in the upper-RPMs.

MySwiss

It also depends , if your using a boost controller. If you are, then it it doesn't really matter. I've been using a .6 bar for two years, in conjunction with a EBC and MBC, which yielded the same steady results. I have run 17psi and 15 psi(steady) with that very spring. The advantage to using the .8 bar, for example, is that you have more flexibility. You can actually lower your boost below 15psi, if you need to.

emilios

My friend replaced the stock wastegate on his 1991 UK-spec 944 turbo S Cabrio with a 38mm Tial and 1.0 bar spring and ended up blowing the headgasket (which @80K miles was/looked tired and I presume would have needed replacing anyway) - Replaced the headgasket and the car is now pinking - the advise he got from Porsche AG was to lower the spring pressure to .85-.9 (as they said the stock fuel injectors will only satisfy boost pressures up to that point i.e. .85-.90). As 100-octane unleaded fuel has now become readily available over here he will start using it before replacing the spring to see if the problem continues or is reduced / solved.

Best regards

Emilios

stoked944

so basically go in between which would be 1.

J Chen

Hey Danno,
Why would you want to hook-up
the banjo directly to the wastegate ?
Would the spring tension matter if we
have a reliaboost in between ?