ct-27/ct-20b helper springs and max boost test results, from ATS racing and Hux racing Options

[lagos]

Did you guys see the results ats got with the ct27 at those same boost levels?

[_Jim_]

Yes, I saw what ATS posted about there CT27.

For those new to this thread, or not up to date, heres a small comparison between the 2 runs.

First HUX's Racing.....Mods list:
Stock GEN3
4" intake
Blitz SBC boost controller
3" single tip exhaust
boost cut defeated.
Helper Spring
100 octane

Max of 351whp at around 5700 rpms at 22psi (highest psi logged, 24psi at 3700rps, falling to 20psi at redline)...AFR around 11.5

ATS Racing.....Mods list:
Stock GEN2 with GEN3 electronics
3.5" intake
Power FC
Walbro fuel pump
550's
ATS FPR (50 psi)
ATS Rail
Greddy PE exhaust
3" downpipe
Helper Spring
C16 race gas

Max of 353whp at around 5700 rpms at 25psi(highest psi logged, 26psi at 5200rps, faliing to 25.5psi at redline).....AFR around 13.0

Hux......................ATS
CT20B..................CT27
351whp................353whp
22psi....................25psi
AFR 11.5...............AFR 13.0
Stock ECU............Tuned via Power FC

[lagos]

The whole secret here is in the race gas and the helper spring.

[Culpable04]

If hux tunes for an AFR ~13, it would sqeeze a few more horses as well, so i would say hux numbers are more real hp numbers as i dont think many daily driven 3s are tune for such high AFR.

[lagos]

^ Thats true, but at this point both turbos are giving it all they got. There really wouldn't be a huge different in power between the two. Id still call it a tie for both of them.

[_Jim_]

I wouldn't call it a "TIE" really, for the main reason being one was tuned, and the other untuned stock ECU. Who knows how far he advanced timing and such, not to mention the tremendous difference in AF ratios. I would have loved to see ATS do this on a stock GEN3 like HUX did, for a true comparison. Good to see similar results from 2 different parties tho.

Yes the "Helper Spring" was the biggest contribution here. Hux seems to be playing around with different actuators all together (without much success yet) where as ATS truly just added a "Helper Spring" to the stock actuator. For those wanting to do this same mod, ATS added a spring that added as much as 30 addition lbs of closing force to achieve an additional 4-5 psi out of the factory wastegate setup. If you look over on MR2oc.com, ATS posted the PSI he logged off his POWER FC, though out the RPM range. He had as little as .5 psi drop from full boost to redline......Where as HUX had about 4psi pressure drop from when full boost was achieved to redline.

A pic of the "Helper Spring" used.

[97celiman]

whats a helper spring?

[_Jim_]

I posted a picture of it on page 4. It is an additional spring added to the wastegate actuator to help to keep the wastegate "flapper/door" from blowing open to allow for higher boost.

[CelicaGT04]

I wouldn't call it a "TIE" really, for the main reason being one was tuned, and the other untuned stock ECU. Who knows how far he advanced timing and such, not to mention the tremendous difference in AF ratios. I would have loved to see ATS do this on a stock GEN3 like HUX did, for a true comparison. Good to see similar results from 2 different parties tho.

Yes the "Helper Spring" was the biggest contribution here. Hux seems to be playing around with different actuators all together (without much success yet) where as ATS truly just added a "Helper Spring" to the stock actuator. For those wanting to do this same mod, ATS added a spring that added as much as 30 addition lbs of closing force to achieve an additional 4-5 psi out of the factory wastegate setup. If you look over on MR2oc.com, ATS posted the PSI he logged off his POWER FC, though out the RPM range. He had as little as .5 psi drop from full boost to redline......Where as HUX had about 4psi pressure drop from when full boost was achieved to redline.

A pic of the "Helper Spring" used.

whats a helper spring?

I had the same question, but after reading JIMs post, I am guessing that a "helper spring" adds resistance to the stock wastegate actuator. Meaning, when the wastegate wants to open (to release pressure), the spring provides resistance from letting the "flapper" open and release the pressure, giving the added PSI (from the now built up pressure), or to prevent any early or unwanted leakage of pressure.

If i am wrong then somebody please, please, send me in the right direction lol. But this seems a logical assumption based on the picture and information that JIM posted.

[presure2]

I had the same question, but after reading JIMs post, I am guessing that a "helper spring" adds resistance to the stock wastegate actuator. Meaning, when the wastegate wants to open (to release pressure), the spring provides resistance from letting the "flapper" open and release the pressure, giving the added PSI (from the now built up pressure), or to prevent any early or unwanted leakage of pressure.

If i am wrong then somebody please, please, send me in the right direction lol. But this seems a logical assumption based on the picture and information that JIM posted.

thats exactly the idea.

[_Jim_]

Yep, you got it. The problem with the factory actuator, is that under high boost the flapper gets blown open. Meaning, if your boost controller was set for say 25psi, the flapper door is being blown open before this boost pressure is reached. And if it is reached it is not allowing the flapper door to open and close as it should to allow for the desired PSI to be achieved to redline. The "Helper Spring" is allowing for addition closing strength to allow for higher boost pressure because the flapper is able to remain closed until desired boost levels are reached.

Just a little heads up, be careful with this mod. Before installing the helper spring, turn your boost controller down to 8-10PSI. The reason for this is because the stiffened flapper door is going to change what the previous boost pressure was set at. For example if your boost controller was set for what you thought was 20psi, might not be 20 psi. The 20psi you were running might actually the flapper door being blown open (maybe) and in fact your boost controller was set for 22-23psi, so with the addition of the helper spring......you will be adding an additional 4-6psi resulting in 26-29psi. By turning the boost controller down to 8-10 psi before the addition of the helper spring you are assured that boost will be within reason after the installation of the helper spring. Then you can adjust the boost controller from there to the desired boost pressure.

[Darkchylde]

Just a quick question, but can I do the same thing for my second gen 3s if I use a ct-20b.

[lagos]

Just a quick question, but can I do the same thing for my second gen 3s if I use a ct-20b.

YES!

[_Jim_]

Just a quick question, but can I do the same thing for my second gen 3s if I use a ct-20b.

Of course you can. It is the EXACT same process. Be careful tho, you will be just about out of fuel around 18psi.

[Fastbird]

Man, this just REALLY reinforces my wants for a good CT20B for our car. I really didn't think it would push that much power, so I'm impressed needless to say.

[95st-celica]

awesome info...totally makes sense and is an awesome little mod...i personaly didnt think the 27 could be pushed to 25 psi before launching but im sure they did this giving it everything it had..its just little things like this that keep advancing and producing great numbers...good work and great info

[lagos]

Just a quick question, but can I do the same thing for my second gen 3s if I use a ct-20b.

Of course you can. It is the EXACT same process. Be careful tho, you will be just about out of fuel around 18psi.

Out of fuel AND out of octane.
You can remedy this by supplementing your fuel with alcohol.