Need help can't boost

[Ghettobaby]

I need help.

I have a ct26/35r on my car, basically a gt35 cold side with a ct26 hot side. Its an amazing turbo that give me full boost at ~4500rpm. But my problem is that I cannot boost pass 11psi. I am using a greddy profec b spec 2 boost controller but no matter what the wastegate (internal) opens at 11psi. I tried a home depot version and same thing. Now my wastegate actuator has 2 ports on it, does it matter which port the boost controller line goes to? I know that the 2nd line needs to be plugged. Could anybody please give some ideas for things to check to solve this.


Thanks

[stevo 27]

if what i pmd doesnt work what area in the city do you live in?
you can drop by and well see if we can figure it out :thumbsup:

[barmanjay]

The wastegate spring inside the actuator itself might only be good for 11psi

meaning you'll need to thread the actuator shaft so you can adjust the length,.. in-turn,.. tightening/pulling the spring in the actuator = bigger boost.

[Ghettobaby]

Originally posted by stevo 27
if what i pmd doesnt work what area in the city do you live in?
you can drop by and well see if we can figure it out :thumbsup:

Yeah I had it set up the way you mentioned and it doesn't work. I live up in the NW but don't mind driving.

[stevo 27]

yea maybe this weekend we can try :thumbsup:

[Ghettobaby]

Originally posted by barmanjay
The wastegate spring inside the actuator itself might only be good for 11psi

meaning you'll need to thread the actuator shaft so you can adjust the length,.. in-turn,.. tightening/pulling the spring in the actuator = bigger boost.

But with the boost controller, I thought that it would restrict the air going to the wastegate until a certain psi and then let it in. So like no air passing through the valve, until it hits a boost amount that I set.

[Milk2%]

Let me ask why you used a toyota ct-26 hotside?

[Ghettobaby]

its an extreme boost turbo. It was built to spool faster than the gt30s and td06, as well as out flow them.

Plus its a direct drop in, which meant something in a time when it was hard to find aftermarket manifolds.

[stevo 27]

Originally posted by Ghettobaby
its an extreme boost turbo. It was built to spool faster than the gt30s and td06, as well as out flow them.

Plus its a direct drop in, which meant something in a time when it was hard to find aftermarket manifolds.

thats interesting i always believed that the ct26 hotside was the most restrictive part

[barmanjay]

Originally posted by Ghettobaby


But with the boost controller, I thought that it would restrict the air going to the wastegate until a certain psi and then let it in. So like no air passing through the valve, until it hits a boost amount that I set.

The MBC will restrict the boost going to the actuator,.. which is pushing on a diaphram to open the wastegate,.. it is still sprung with a spring and the spring inside might only be good for 10-11 psi.

understand?

[Ghettobaby]

but how will the spring know when there is 11 psi of pressure on it if the mbc is restricting the air pressure.:confused:

[barmanjay]

the wastegate is being pushed open on the ehxaust side, by the exhaust,.. not boost from the manifold

[stevo 27]

that theory doesnt work though i have a stock ct26
the wastegate spring is good for 7-8psi and i see 16-17psi everyday
i garrentee that it has something to do with the boost controller

and theres no way the exhaut pressure could open the wastegate

[barmanjay]

Yes exhaust pressure can push open a wastegate,.. my car is living/running proof


Some actuators work in reverse,.. using boost and a boost pressure solenoid to push the diaphram closed (weak spring wastegate actuator)


so in theory you could also be correct with a problem being the controller

[stevo 27]

yes i know your theory can work
but i cant see that happening on a ct26 just from the
design of it

[Annoyingrob]

Originally posted by Ghettobaby
Now my wastegate actuator has 2 ports on it, does it matter which port the boost controller line goes to? I know that the 2nd line needs to be plugged. Could anybody please give some ideas for things to check to solve this.

This is your problem right here.

Yes it matters which port is plugged in, and NO the other port should not be blocked off. Whoever told you that doesn't know what they're talking about.

I will guarantee your problem is a misconfiguration with your vacuum lines.

There are two ports on the wastegate, one closest to the actuator arm, and one further away. The far one is the boost line, and the close one is a pressure reference port. The far port should be plumbed right into a boost source, while that clsoe one will feed into the COM port on your solenoid. The NC port on the solenoid is then plumbed into a pressure source as well. The NO port on the solenoid MUST REMAIN OPEN TO ATMOSPHERE.


That should get you up and running.

[Ghettobaby]

Originally posted by Annoyingrob

This is your problem right here.

Yes it matters which port is plugged in, and NO the other port should not be blocked off. Whoever told you that doesn't know what they're talking about.

I will guarantee your problem is a misconfiguration with your vacuum lines.

There are two ports on the wastegate, one closest to the actuator arm, and one further away. The far one is the boost line, and the close one is a pressure reference port. The far port should be plumbed right into a boost source, while that clsoe one will feed into the COM port on your solenoid. The NC port on the solenoid is then plumbed into a pressure source as well. The NO port on the solenoid MUST REMAIN OPEN TO ATMOSPHERE.


That should get you up and running.

I will try what you mentioned. However the greddy boost controller manual is what says to plug the 2nd port on the wastegate actuator.

[Ghettobaby]

I did not get the chance yet to try what Annoyingrob mentioned, but today when I was driving I noticed that my boost was now limited to 5psi. I checked the intercooler piping again and there are know leaks. Could my t-vis have anything to do with the boost I am making.

Thanks

[stevo 27]

there are no leaks??
or now leaks??

your tvis might have shit themselves and are staying shut
VERY UNLIKELY but a possibility

im with rob im sure you have the vac hoses all mixed up
and if your only gettin 5psi you have a lasy wastegate aswell

[barmanjay]

Something is terribly wrong if you went from 11psi to 5 psi inside of a week

[Ghettobaby]

Good news I'm back up to 11psi, I dunno what it going on with my car. I didn't touch anything and am now back where I started.

Oh and Annoyingrob, I tried what you mentioned but it still only goes to 11 and then tries to surge pass, so I assume that my wastegate is either messed up or my boost control solenoid is not working.

[Annoyingrob]

I'm sure the manual specifically states to have the port open. It uses it to vent excess pressure to atmosphere so the wastegate receives a lower pressure.


So it's still not working eh? What I would do is remove everything, just run a single line from a pressure source to the port on the back of the wastegate actuator, and leave the other one open to atmosphere. This should cause your car to run at spring pressure. If you get a consistent boost then the problem is in the boost controller, if you are having spiking problems, then the ports on the actuator are backwards from what they should be.

[Mike w]

just throwing this out there, but is it possible it has something to do with the ecu, maby it wont let u boost past 11, i know i had to change mine out when i wanted higher then 7 i think

[Milk2%]

well just for your information ct26's are restrictive after 5500! you are saying your using the hotside of a ct26 correct? i hope there is some major porting involved, because thats where the ct26 actually become restrictive in making power. I really hope you didn't purchase this through ebay. Can you give me some more information about this turbo. because it would be literally amazing. I highly doubt you will find a ct26 spooling and out flowing any gt30. td06.

[Ghettobaby]

Originally posted by Milk2%
well just for your information ct26's are restrictive after 5500! you are saying your using the hotside of a ct26 correct? i hope there is some major porting involved, because thats where the ct26 actually become restrictive in making power. I really hope you didn't purchase this through ebay. Can you give me some more information about this turbo. because it would be literally amazing. I highly doubt you will find a ct26 spooling and out flowing any gt30. td06.

Wow what a thing to say when you don't know what you are talking about. This turbo doesn't even give full boost until 4000rpm and has no problem holding the 11psi (though it climbs to about 13psi) until 8000rpm. This is an extreme boost turbo, built to be a high horsepower drop in. CT26/35R (http://www.extremeboost.com/specials/CT26-35R.htm) Just click back at the bottom of the page for the specs. I only know of 2 other mr2 owners with this turbo and both are making +350whp.

[Milk2%]

Originally posted by Ghettobaby
I need help.

I have a ct26/35r on my car, basically a gt35 cold side with a ct26 hot side . Its an amazing turbo that give me full boost at ~4500rpm. But my problem is that I cannot boost pass 11psi. I am using a greddy profec b spec 2 boost controller but no matter what the wastegate (internal) opens at 11psi. I tried a home depot version and same thing. Now my wastegate actuator has 2 ports on it, does it matter which port the boost controller line goes to? I know that the 2nd line needs to be plugged. Could anybody please give some ideas for things to check to solve this.


Thanks

[stevo 27]

thats awsome for a drop in
are the hot side blades clipped?

he never said it was a stock ct26 hotside

and thats exactly what i thought in the description it
says modified so obviously porting clipping

i think its cool

[Ghettobaby]

Milk2% - OK my bad, I see where you got your information from. When I stated that I was simply trying to simplify it. I apologize for my previous comment.

Mike W - The ecu is not the problem. I am running a full standalone and what I am experiencing is not a fuel cut. I am almost 100% certain that my wastegate is opening when I hit 11psi.

I can almost confirm that it is the boost controller. I looked through the good ole BGB and it says that the stock wastegate actuator should open at 11.3psi max. So now does anyone have a known working manual boost controller that they are looking to sell??

[stevo 27]

shitty i just gave mine away

make one yourself ;) i did for the longest time before i decided
to just block off the wastegate completely

take some braided hose drill a 1/4 hole in it or more connect
it were the stock hose would have been and your golden ;)

until you buy another boost controller :thumbsup:

[Milk2%]

http://forums.turbobricks.com/showthread.php?t=59089

Its simple and probally one of the better homemade boost controllers. A healthy (2gen 3sgte motor"which i think you have) should boost around 11 psi, with a free flowing exhaust. Once i installed my downpipe i saw 2psi gains. Thats a pretty nice turbo by the way, i wasn't to sure about the turbo but awesome to clarify. Im planning on the gt28rs, or just a ct20 till i build my monster. Wait till you get over 20psi on that puppy!

[Annoyingrob]

if you think it's your boost controller, what settings did you have your profec B set with?

[Ghettobaby]

Originally posted by Annoyingrob
if you think it's your boost controller, what settings did you have your profec B set with?

Set: 40%
Gain: 35%
Set Gain: 13.0
Warning Is cranked up all the way and Limiter set to 0

[Ghettobaby]

Well lucky me, I just remembered that I have a boost solenoid for my aem so I plan on installing that (once I figure out which port is what). But I also realized that if my wastegate is opening even when there are no lines connected to it, then that must mean that the wastegate itself is the problem. Am I right? Is there anyway that I could create a vacuum in the wastegate to test if I can boost pass 11psi?

[stevo 27]

you have no pressure line to the waste gate actuator?
and you still can boost past 11psi

[Ghettobaby]

Right, I took every line off the wastegate actuator and still only got 11psi soild and some creep in 4th gear.

[stevo 27]

well than you have some major restriction in the exhuast
your tvis shit themselves and arnt openening fully orr
like said early your wastegate is opening i dont see how my ct26
is over 10 years old and my wastegate is holding 18psi ???:dunno:

[Ghettobaby]

The exhaust is a full 3" kakimoto right from the turbo all the way back. Man if it is the tvis then its time for a new manifold :D and if its the wastegate then shit, thats a mofo to change out.

[stevo 27]

Originally posted by Ghettobaby
The exhaust is a full 3" kakimoto right from the turbo all the way back. Man if it is the tvis then its time for a new manifold :D and if its the wastegate then shit, thats a mofo to change out.

ats makes hollow tvis plates for 150

if your turbos waste gate is toasted guy o mr0c is selling a gt30r for a wicked price

exhaust has no cat
primary cat is gutted?

[Ghettobaby]

no cats, yeah I'm gonna pick up a new actuator and the tvis plate form ats.

[Redlyne_mr2]

yo man ill get in on a tvis plate with you if you decide to order one

[stevo 27]

sounds good hopefully that solves all your problems :thumbsup:

[Ghettobaby]

Yeah if it doesn't I'm just gonna get a complete gt35 kit and stroke the engine when my funds allow for it.

[stevo 27]

thats what i want to but a gt40r next seasom for sure
what mods do you have as of now?

[Ghettobaby]

Before I commit to anything one last question. Is there any way that I can test if it is the wastegate? For example could I use a mityvac to create a vacuum inside the wastegate to hold if firmly closed and see if that allows me to boost past 11. In theory I think this would work.

[stevo 27]

i dunno possibly never seen it done

[barmanjay]

afaik: there is no real test for wastegate actuator springs.

But with the actuator out,.. you may aswell do this mod:

cut the arm in 2 and thread each end,.. then use a deep nut (so to speak) you may have to tap/make your own)

this way if you think your wastegate is too loose/not enough pressure,.. just pop the arm off the exhaust side and give it a few turns to shorten the arm length then re-attach to the exhaust side.

Now you've upped the spring psi prerssure to open by 2-3

[Annoyingrob]

Originally posted by Ghettobaby

Set Gain: 13.0

That's your problem. What this means is the solenoid will not activate until you hit 13psi, which is above what you're going to hit on the WG alone.

lower the set gain to 9 or 10psi, and you'll be boosting.

[Annoyingrob]

Originally posted by Ghettobaby
Is there anyway that I could create a vacuum in the wastegate to test if I can boost pass 11psi?
Pull the lines off of it. But I would NOT do this if you don't have a boost cut on your ECU.

[stevo 27]

Originally posted by Ghettobaby
Right, I took every line off the wastegate actuator and still only got 11psi soild and some creep in 4th gear.

so somethings up

[Ghettobaby]

Well things keep getting better for me. This evening I ran some seafoam through the engine (thru the brake booster hose) and it appears as though I have an exhaust leak between the turbo and manifold (yay!!!). But anyway it took the car for a spin to get red of the heavy white smoke and felt a huge difference in the cars performance. In 2nd gear I was able to get 16psi, but in 3rd and 4th I am still only seeing 11psi plus some creep. So my plan for the weekend is to pull the turbo and replace the exhaust gasket and put on a 2nd wastegate actuator. Man I hope this solves all my problems.

[Annoyingrob]

yes. a pre-turbo exhaust leak should be fixed before any more trouble-shooting can be done.

[Ghettobaby]

The problem was so simple and the solution was so cheap. The problem was that my wastegate actuator arm was too long so that wastegate was never fully closed.
The solution I used was to put a few washers between the wastegate actuator and turbo to pull the wastegate shut. I am now seeing crazy boost faster than before and 20psi in 3rd gear (boost controller settings). YAY, time to go back to the dyno. :burnout:

[stevo 27]

pulls a hell of alot harder now ??:D :burnout:

[Ghettobaby]

Oh yeah, I'm almost scared of it now. :eek:

[barmanjay]

Originally posted by Ghettobaby
The problem was so simple and the solution was so cheap. The problem was that my wastegate actuator arm was too long so that wastegate was never fully closed.
The solution I used was to put a few washers between the wastegate actuator and turbo to pull the wastegate shut. I am now seeing crazy boost faster than before and 20psi in 3rd gear (boost controller settings). YAY, time to go back to the dyno. :burnout:


hahahaha!!

SWEEET!!!

I forgot about doing that trick :D

[stevo 27]

your not on stock internals are you?
im not gonna put the gt35r on till i get some new pistons/rods

[Ghettobaby]

Originally posted by stevo 27
your not on stock internals are you?
im not gonna put the gt35r on till i get some new pistons/rods

Yes I am. I don't plan on having this engine last very long, but because it's so pricey to pull it and send it out to get built properly, I figured I would wait until it was essential.

[stevo 27]

well when you go to the dyno tell me how far you can push her
im intrested
i wont push the stock internals past 350whp

[Annoyingrob]

yes, please post dyno results. I'm very interested in seeing how the hybrid CT26/GT35R performs. There are a few guys starting to use these in the Supra community as wel.