JBrown

I know that the GHL and Tial combo makes more boost than a stock wastegate on the same exhaust. What spring size do I not to be around 11-12lbs of boost. I was thinking about .7 tial spring. What do you guys think.
Thanks John

A930Rocket

If it's a new set of GHL's you might be able to run a 1 bar spring. You just need to make sure it has the bigger wastegate pipe. I installed mine with the bigger wastegate pipe and with a .7 bar spring, it ran at .7 bar. Tried a .8 bar and got .8 bar. Tried a 1 bar spring and I have .95 bar.

I would say a .8 spring.

ayglass

My older GHL and stock wastegate with a Fabspeed muffler makes 1.05bar with a .8 bar spring. I guess I have another upgrade in my future :-)

JBrown

My exhaust is about 5 yrs old and I know I was getting close to 18lbs of boost with a 1 bar spring. I am breaking in a new motor with a small spring and getting ready to get it dyno tuned and want a spring to give me about 12lbs boost. I was thinking .7 bar.

pzull

I think boost reading depends on where you install the sensor and also the sensor itself.

I have a 0.9 bar spring but the readings I get are as follows:
a) Autronics ECU, max boost 0.86
b) Zeitronix, max boost 0.97
c) Factory gauge, cannot read the max boost as it tops out at 0.7 but it reaches 0.7 when my Zeitronix reads only 0.4 bar

a+b have sensors in intake manifold while factory's sensor I believe is somewhere upstream in the IC

So I dont know which I should believe. Any views?

ProtoCab

I have the GSF/Schnell headers with a TiAL46mm & 1.0bar spring and I get pinned at 1.0bar every time. Very accurate! I use my Apexi AVC-R EBC to regulate max boost to 1.1bar tho.