This is what I found out from the search:

Red: 16~20psi
Yellow: 11~15psi
Green: 5~10psi

What's blue spring rated for? I think it's in between the red and the yellow.
Also, which spring should I use for my setup?
APS TT+GTM built engine+GTM turbo cam+3.5" APS TP+3" Evo TT
exhaust+HKS evc boost controller+water&methanol injection.

I'm shooting for 15~17psi 600whp on 91 octane pumped gas with water&methanol injection.

I know Zivman is running the red springs for ~16psi, but he has 2.5" exhausts.
Since my exhaust will be more free flowing, should I be running one step lower? Would that be the blue spring?

Thanks in advance guys.

 

My tuner is suggesting the blue spring but I'm not sure of it's spring rate. I'm running the EVO TT exhaust with 2.5" TPs.

 

what i have learned is that you can make less boost than the springs if you want but you cant make more than they are rated. i would go with the red springs but you will be limited to around 10-11 for low boost...


DONT go to low or you will regret it cause its a lot of work to change them..


i would say red

 

^ isn't that reversed? With a boost controller, you can set the boost as high as you want but you cannot lower it below the base for the spring. I mean the controller will switch between connecting the wastegate port to the intake port, or connecting the wastegate port to the atmosphere port (as long as this is the case boost will continue to build), right?

 

as Jeremy said, go with the Red, I have swapped springs several times!!!

My setup:
APS tt
3.5L
3" true dual exhaust
3.5" downpipes
blitz sbc-id boost controller

with bc off: 10-11psi
low boost: (set 35): 14.5psi
high boost (set 70): 18psi

yellow will not allow you to go much higher than 16.5, maxed out, the red will give you more room to work with

TODD

 

This is why I want to make sure I put in the correct spring for my setup before the installation begins. I'm overseas, so I have no expert tuner to advise me on this matter...

So what's the blue spring rated for?? Nobody knows??

 

Wow! You only get 10~11psi with boost controller off with the red spring?? I thought Zivman was getting like 13psi with BC off... Too many contradicting stories... This is what I'm concerned with the most... I want to be able to lower the boost to 13~14psi with the red spring, but I'm not sure if that's possible.

 

What's your WHP, psi goal?

 

I understand the blue is rated somewhere between the red and yellow. I'm hoping for 525-550whp.

 

This is what Sharif said on the other thead... I'm confused...

 

I ran the red springs with the 3.5" pipes into the 2.5" exhaust. I was consistantly pulling almost exactly 14 psi with my EBC off (EVC 5). I set the actuators with 1/2 hole preload. Set to 24 on the EBC, I was seeing about 16.5-17 psi and at 30 on the EBC, I was seeing about 17.5 psi.

 

if you look on the end of the box i shipped them to you in, they are written down on there, the spring rates.

 

ohhh.. +1 on the red springs .. just get em in and you wont have to change again.

 

yes but if you hook the boost line up straight to the ports on the actuator with no boost controller, you will make the least amount of boost possible.



internal and external wastegates are exactly backwards of each other when it comes to boosting and boost controllers...

 

+1... too bad we had to learn the hard way..

 

iirc the blues are 19-25psi.

go with red, if you go with blue, youre gonna be overshooting your goals, you can always use a controller to go higher, but you cant go below the spring pressure.

 

Thanks guys, I didn't look at the box.. Thanks for the info!
$h!t~ blue's rated higher?? Good to know.. Red it is..

Now I just need to find/order an extra red spring... Anybody want to donate a spare red spring? I'll put you down as my sponsor! LOL I just might have to ask Sam@GTM when I order the GTM turbo cams..

 

Now I'm confused, I understood from Zivman the red ones are rated higher than the blue.

Old 05-12-2007, 05:46 PM #5
Zivman
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Join Date: Jun 2003
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[Quote=Zivman]

Originally Posted by BrianLG35C
So you feel the red springs are best for the APS TT application?

I would say at least get the blue springs. and if you are comfortabel with 13+ as the lowest amount of boost, go for the red ones. IMHO, over 13 lbs on spring pressure is a bit much.

Brian, you will also be running a slightly bigger exhaust with the EVOTT - I don't know if it flows better than the aps 2.5", but I would think it would. That being said, you might be better off with the blue ones. Talk to Tuan and see what he thinks
__________________

 

The reason this is confusing, is becuase internal wastegates are dependant on the amount of preload you put on the arm, and they are very sensitive to backpressure. So bigger exhausts and downpipes will make more boost. Bench testing is the only way to know for sure. I have seen yellow springs push 16psi easily with a boost controller (about 8psi WG only), but other customers have reported that they can't get more than 13psi...even with a boost controller.

With a built motor, it definately comes down to red or yellow. Blue is going to make 20psi plus...that's a nasty spring.

 

I hear you.. Forge actuator website doesn't have any info... I'm gonna checkout the box as Tig mentioned when I get off work... (it's 11:17am in South Korea)..