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All the internally gated turbos I have seen/used have some adjustment in the length of the actuator rod.

Cool cool.

I assume this is not the sort of thing I should just play with and 'see how it goes' but rather stick it on the dyno?

what do you want to achieve ?

Just to see if it helps bring the boost on a little faster - looks a little lazy coming on... The other side of it is playing with boost controller gain etc.

If it's something I could do myself without a big $$ outlay on dyno time (as i've just forked out a crapload to get here!) then i might play with it. If it's a bad idea to do it by the seat of my pants dyno / boost gauge then i'll wait till i do something else on the dyno...

post-71984-1275542484_thumb.jpg

adjust little bits at a time, take it for a drive.. but ur going to need to turn ur settings down on the boost controller, as making it tighter/harder to open is going to want to raise the boost level.. so turn gain down etc

Turn boost controller off take it for a run not when you hit max boost.

Adjust arm length a tiny bit and go for another run and not when max boost it ( boost will likely increase as well)

Keep doing that until you get no more gain but be careful your not over boosting.

When you have found the sweet stop user boost controller to hit desired boost.

Are you using the actuator that came with the turbo?

They arent the greatest, quite soft and creep open a bit, that's probably causing the slow boost.

I got one for a mate for his 3076 from USA, 14psi spring. The overall size was larger, and it was tight as buggery compared to the "stock" actuator. (when doing the old "pull on this" trick) :blink:

PM "Lithium" and ask him a question or two. Hes tried a few different approaches to the spool issues.

Edited by gotRICE?
Are you using the actuator that came with the turbo?

They arent the greatest, quite soft and creep open a bit, that's probably causing the slow boost.

I got one for a mate for his 3076 from USA, 14psi spring. The overall size was larger, and it was tight as buggery compared to the "stock" actuator. (when doing the old "pull on this" trick) :blink:

PM "Lithium" and ask him a question or two. Hes tried a few different approaches to the spool issues.

Boost controller is a Greddy profec II spec B (or whatever it's called).

I 'asked' the place that built my car to get the larger actuator on the 3076 as apparently it comes standard from Garrett... I can't seem to move the rod at all by hand...? (and i'm not a small dude)

There is a thread on the rod, so could turn off the boost controller as suggested and see what tightening or loosening it does...?

to add more preload to the gate wind the road so that the overall length is shorter. only do it a few mm at a time tho. once you have enough preload to keep the gate shut properly use the profec to bring it on earlier by slowly increasing the gain and start/set boost until it spikes then back it off a touch. if you want 18psi i'd start with a set boost of 14-15psi and wind the gain up.

this will change the torque around that area. ideally you should get the tune checked around that area but if you dont want to do that just keep a close eye on your knock levels (if possible) whilst adjusting the boost.

Well here's an advertisement for not always taking dyno readings as gospel - I did some testing on the road on the way to work this morning - it's kind of hard to tell exactly since i can't use WOT in 2nd as the back goes by 4500rpm or so but i was making over 1bar by 4000rpm and was definitely at the full 18psi well before 4.5k. At which point i was going sideways down the road and had to back off... :blush:

I assume the tuner didn't plant his foot on the dyno from down low and this is why it looks lazy onto boost on the chart...?

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