Actuator Pre-load
Turbo Mini Forums

I'm planning to fit the turbo to the 998 in the next few days at long last.

I'm using a standard R5GTT, Garrett T2 turbo and actuator.

Any idea what boost the standard actuator runs at and what sort of preload I should set it at for about 7psi boost to start with?

Thanks.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

0.540 - 0.610 bar = 0.38 mm
0.740 - 0.820 bar = 4.00 mm

theres the rod movement at different pressure paul,,so prob ,0.75 bar average id guess at . usual pre load is half a hole tension .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Thanks Robert.

Half a hole it is then.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Agree, half a hole. Nic advised me of this when building mine and I achieved 6psi.
Cheers
Shane

Yes, half a hole gave me 8 psi boost.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

We need to up the boost for MITP.

So what do I need to get 12 psi?

3/4 hole?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

For the record, it took a total of eight full turns on the 1/4 UNF actuator rod to get up to 12 psi.

That's roughly 1/2 psi per turn.

Took all afternoon doing it in stages and having to cool it down with the airline between runs so that we could adjust the rod.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

i put an R clip through then i can do it hot on the rollers with pliers

sorry to resurrect and old thread but this ties in with what im asking.

I have bought a t2 hybrid turbo and its all fitted, but ive had to temporarily set the preload to 1 1/2 holes...(cause the actuator rod isnt long enough) i drove the car home and i dare not use full throttle.. i gave it a blast on my street but i took my foot off the throttle when it got to 10psi. i found a website that sells an actuator very similar to mine and it says its standard 5psi...and im assuming that its 5psi at half a holes preload? it did take a hell of a lot to pull the rod out compared to my old t3 one. does the more effort needed to pull the rod mean its a higher boost actuator?

This is the actuator i have.

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Obviously the more pre-load you add, yes the more boost it will take to operate. If indeed it actually has any travel left to operate.

Lengthen the actuating rod.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Use a foot pump or similar connected to the boost line on the actuator to pump it up a little, this will push the rod out enough to get it onto the arm.

i bought a little thinga-ma-jig to use with the footpump idea, but then i just thought, fuck it, take it all off and do it right! anyway to wrap this up, that actuator is a 9-10psi spring with HALF a hole preload... i had it at 1 and a half holes at first :S good thing i never fully belted it!!!