This is a wierd question I know but reguarding turbo life .

would the turbos take less abuse if it were in none sequential , during cruising rpms . IE 3500 rpms both turbos spinning , VS having only the primary spinning ?

with both turbos theoretically spinning at lower RPMS , and pushing more air compared to having only 1 turbo having all the flow directed at it to cope with the load.

ofcourse we're talking in light load vacume situation , where the turbos arent really spinning all that much . but still spinning .

strictly theoretically

my question kind of originates from vacume I have my secondary turbo come online at 4k rpms , when cruising at 3800 my vacume is less then when it passes the 4k rpm threshhold which it then gives me move vacume when the secondary turbo opens up .

So I was curious if cruising with both turbos online would be a good thing or a bad thing .

 

i think running fully non-sequential would be better for engine longevity simply because you're removing (or wiring open) the big exhaust flapper that redirects the exhaust flow to the primary turbo for 99% of your driving.
running non-sequential lowers EGTs and runs both turbos all the time, which i would say keeps the heat down and both turbos working less overall (as compared to utilizing the flapper retaining heat, and one turbo doing 99% of the work).

 

ok ok we got one pro both turbos during cruising ? anyone on the other side of the fence?

 

i dont think there's going to be much competition from the other side of the "fence," as it's just physics. removing (or even wiring open) that exhaust flapper is going to let more heat flow through the turbine wheels (and ultimately out of the downpipe) and split the exhaust load to two turbos. as far as reliablity and heat is concered, there's no downside.

the downside is lag.

 

unanimous decision ?

 

The engine is designed for sequential twins and handles the abuse they give it fine it's when fools add a straight exhaust and boost the thing to 14 psi that hurts the engine.

Hell if you want what is best for the engine just take the turbo off

However what's best for the driver is a sequential twins

 

If we assume say 3500rpms engine speed, I think it would highly depend on the exact amount of torque the engine needs to produce for the driving condition. If you're at road load, like driving on a flat surface, turbos might be barely spinning at all. If the stock turbos are rated to 130k rpm, and running non sequential drops your max turbo speed from 30k to 20k, would it make a difference? Probably not. You're so far from the speed limit of the turbo. That's all hypothetical though.

Now what you have to consider is that with a "poor man's nonsequential," you need to use the engine more to spool up two turbos rather than one. There has to be exhaust-derived power to turn both turbine wheels enough to make boost. I can see at certain points you might be generating a bunch of extra heat to spool two turbos rather than one. That could degrade turbo life by heating up the oil, turbine housing, bearings, etc.

Without a gazillion sensors all over the engine bay it's just speculation though.

 

thanks , and I dont plan on going none sequential I love the sequential system way tomuch just working on a bit of research

 

If you really like your sequentials, get Azeknights(sp?) solenoid rack for them. The transition is incredibly smooth now. Its as good as it should have been from Mazda.

Jason

 

I'm in hte proccess of an expensive rebuild lmao , right now oem solenoids are just fine.

BUT thank you for the advice if my solenoids start to go bad i will definitely give them a try