To wastegate... Or not to wastegate!
 

That is the question

Im setting up twins on my 96, just wondering what you guys normally do with twins. Its going to be a s475 on a 35/40. Not sure if I should leave the gate on the small charager, add one between the two............

Any insight would be great.

gate! drill the wastegate hole through the center volute so that it gates all cylinders.

I assume youre referring to the small charger - That's what I've read, just wasn't sure.


As for the big turbo.........

the big charger does not need a wastegate as it will eat everything the little 5.9 can give it.

:tu:

To flog a dead horse, is there any benefit to running a larger gate? Im used to gas turbo stuff, that small internal gate makes me nervous :nope:

yes less drive pressure behind the small charger.

I would suggest the WG charger , IT WILL help with spool, seen the difference Too manny times ....

K31 in a S60 .. bus lagged w/o WG turbo .. installed a new one same day .. drove it out of the shop and made it 2 miles , Driver had a big grin .. MUCH BETTER ....

And in a Compund set up .. your gonna want the small charger to get movin as fast as possible off the line ...

In reality if the turbos have the same exhaust housing, then they should spool at the same speed. A waste gate will bleed any excess boost and could harm spool up if it is sticking open and bleeding boost or if it is creeping. A non gated turbo is really only a big issue if you are not set up to handle the potential boost it will create. At that point you need to count on pedal control to make sure you are not over boosting. Having said that, I cannot ever recall anyone running a non gated turbo as the feed unit in a set of twins so I would likely run either a gated unit or an aftermarket external gate.

Yeah and you would want to releive the Drive pressure when going from ON the throttle to OFF the throttle .... if not it could spike the pressures and break shafts or wheels .. :argh: