balancing boost pressures

gazmk2 · Post by **gazmk2** » Sat Feb 19, 2011 12:50 pm

Hi guys, my soarer has twin parrallel operating turbos, the car is now over 20 years old and although the turbos are much newer they are still 8 years old. I have been thinking lately that is it possible that one actuator might be better than the other making one turbo boost harder than the other? They both blow through a common outlet to the intercooler but to make sure that both turbos are boosting at the same pressure is it possible to have a common pressure hose between the 2 turbos instead of a seperate one for each? I was thinking of a T piece on each line between the turbo and the actuator, then connect a length of vac hose between them to balance them out, would this work or have I just confused you all?

Cheers Gary

Post by **Stuart** » Sat Feb 19, 2011 5:55 pm

I know what you mean Gary.........just

No idea what the answer is though! I would have thought that you would need to check both actuators are the same spec, rather than rely on one doing the job of two. Maybe I didn't understand your question........off to research

gazmk2 · Post by **gazmk2** » Sat Feb 19, 2011 6:11 pm

I was more thinking of the actuators wearing out at different rates meaning one opens the wastegate before the other.

warboys · Post by **warboys** » Wed Feb 23, 2011 12:54 pm

You can test the actuator with a hand held pump. Any decent tuner can do this for you.

turbomart · Post by **turbomart** » Wed Feb 23, 2011 7:40 pm

You have lost me, there is no pipe between the turbo and actuator..do you mean between the boost solenoid and the turbos ?? in which case it will make no difference at all.

Fast Eddy · Post by **Fast Eddy** » Wed Feb 23, 2011 10:13 pm

Yes, you can check the pressure that the actuators open at with a pump and guage then adjust so that they both open ate the same pressure. This not not mean that the will then open further at the same rate though if one of them has a spring weaker than the other. Best to do the same process with 2 matching new acuators.

Eddy

warboys · Post by **warboys** » Wed Feb 23, 2011 10:29 pm

Using a pump like this:

http://www.machinemart.co.uk/shop/produ ... tive-tools

You can check the vacuum and adjust the actuators to suit. I doubt you will ever get it to perfectly match.

As FastEddy has stated, it depends on the spring rates and the diaghram condition.

turbomart · Post by **turbomart** » Thu Feb 24, 2011 8:17 am

Unfortunately there is no way you can realistically make sure that both turbos are running at the same rate. One will always fail before the other for whatever reason, be-it differences in actuators or even the wastegate seats themselves which are also prone to wear at different rates. My car runs the same setup as yours and I have had no issues in the 9 or 10 years I've owned her, it will probably happen one day but hey time for some bigger ones.

Martyn

gazmk2 · Post by **gazmk2** » Thu Feb 24, 2011 8:42 pm

turbomart wrote:You have lost me, there is no pipe between the turbo and actuator..do you mean between the boost solenoid and the turbos ?? in which case it will make no difference at all.

There is a pipe going from each compressor housing to each turbo. No solenoids or anything. It doesn't help that the rear turbo is a pig to get to either!!

turbomart · Post by **turbomart** » Thu Feb 24, 2011 11:48 pm

I see, so you have no way of controlling your boost then, it just runs what your actuators are set at ?