
15psi after replacing cat with 3" downpipe
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Re: 15psi after replacing cat with 3" downpipe
Whats up with metal head gaskets? 

Re: 15psi after replacing cat with 3" downpipe
Just had a read through
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the wastegate is more than likely catching the downpipe this is so common its a mr2 cliché
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some people have dremeled the downpipe so it doesn't catch
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As for porting i used carbide cutters and a dremel to do the porting
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worked well i had 1psi boost creep after on a ct20b
, result












As for porting i used carbide cutters and a dremel to do the porting







Re: 15psi after replacing cat with 3" downpipe

masterbateson wrote:Whats up with metal head gaskets?


nothing.

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Re: 15psi after replacing cat with 3" downpipe

mr299ron wrote:That seems like a right god damn pain.
I think the best way to sort this would be to install the correct supporting mods.IC and a metal headgasket.
.
although the headgasket looks like a sh1te job too.
.


How does fitting that help?
Re: 15psi after replacing cat with 3" downpipe

markstevieandmads wrote:mr299ron wrote:That seems like a right god damn pain.
I think the best way to sort this would be to install the correct supporting mods.IC and a metal headgasket.
.
although the headgasket looks like a sh1te job too.
.
How does fitting that help?


Rev1/2 head gaskets like to go pop approaching 15psi










Re: 15psi after replacing cat with 3" downpipe

2mad wrote:markstevieandmads wrote:mr299ron wrote:That seems like a right god damn pain.
I think the best way to sort this would be to install the correct supporting mods.IC and a metal headgasket.
.
although the headgasket looks like a sh1te job too.
.
How does fitting that help?
Rev1/2 head gaskets like to go pop approaching 15psi.
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bit of a pain if you want to push it
.
.
.
ps.
mine held over 15psi but i could be the exception to the rule
![]()


Doesn't help they're made of paper.





Rev 3 metal head gasket all the way.


Re: 15psi after replacing cat with 3" downpipe
Ps
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Bob can do a smooth port job on a ct way better than me
(properly drilled not diegrinded
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pm him









Re: 15psi after replacing cat with 3" downpipe
You REALLY don't want to be boosting to 20psi, even for a second.

The fact you've completely illuminated fuel cut is a receipt for disaster!
Hitting 20psi could have easily blown your Pistons!

There is a reason why folk fit a fuel cut defender and not just block the pipe.


You cannot tell if the wastegate flapper is hitting the downpipe without at least disconnecting the actuator arm
(by the downpipe).
Problem with this is it's a pita to get to! You simply can't see it,only feel.
Getting off maybe ok, but putting it back on, jeeez.
Not impossible though.

Didn't folk warn you already about eBay down pipes? Pot luck really if you have issues with wastegate flapper
(Yes japspeed sell the same as the eBay bits).

On q separate note do you have the support plate fitted to the downpipe?


There is a good reason why people do this mods at home because of issues with product quality.
Your mate/mechanic couldn't have known the flapper was hitting the downpipe unless he removed the actuator arm to test or applied 7psi to the actuator.
Both of which I highly doubt he did.


The fact you've completely illuminated fuel cut is a receipt for disaster!
Hitting 20psi could have easily blown your Pistons!

There is a reason why folk fit a fuel cut defender and not just block the pipe.



You cannot tell if the wastegate flapper is hitting the downpipe without at least disconnecting the actuator arm


Problem with this is it's a pita to get to! You simply can't see it,only feel.




Didn't folk warn you already about eBay down pipes? Pot luck really if you have issues with wastegate flapper



On q separate note do you have the support plate fitted to the downpipe?


There is a good reason why people do this mods at home because of issues with product quality.

Your mate/mechanic couldn't have known the flapper was hitting the downpipe unless he removed the actuator arm to test or applied 7psi to the actuator.


Re: 15psi after replacing cat with 3" downpipe

jimGTS wrote:You REALLY don't want to be boosting to 20psi, even for a second.
The fact you've completely illuminated fuel cut is a receipt for disaster!
Hitting 20psi could have easily blown your Pistons!
There is a reason why folk fit a fuel cut defender and not just block the pipe.
You cannot tell if the wastegate flapper is hitting the downpipe without at least disconnecting the actuator arm(by the downpipe).
Problem with this is it's a pita to get to! You simply can't see it,only feel.Getting off maybe ok, but putting it back on, jeeez.
Not impossible though.
Didn't folk warn you already about eBay down pipes? Pot luck really if you have issues with wastegate flapper(Yes japspeed sell the same as the eBay bits).
On q separate note do you have the support plate fitted to the downpipe?
There is a good reason why people do this mods at home because of issues with product quality.
Your mate/mechanic couldn't have known the flapper was hitting the downpipe unless he removed the actuator arm to test or applied 7psi to the actuator.Both of which I highly doubt he did.


Sounds like a pain in the as.





I hit 20psi literally once dude.



Re: 15psi after replacing cat with 3" downpipe
please explain why its
"all good" by buying
"supporting mods, such as a berk intercooler"

that isnt resolving the problem.



that isnt resolving the problem.

Re: 15psi after replacing cat with 3" downpipe

mr299ron wrote:That seems like a right god damn pain.
I think the best way to sort this would be to install the correct supporting mods.IC and a metal headgasket.
.
although the headgasket looks like a sh1te job too.
.


And low compression pistons
Designer for turbo set ups on F1 cars, and Nitrous Oxide Systems of the USA in the 80s
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- Posts: 547
- Joined: Sat Jan 24, 2015 7:09 pm
Re: 15psi after replacing cat with 3" downpipe

jimGTS wrote:You REALLY don't want to be boosting to 20psi, even for a second.
The fact you've completely illuminated fuel cut is a receipt for disaster!
Hitting 20psi could have easily blown your Pistons!
There is a reason why folk fit a fuel cut defender and not just block the pipe.
You cannot tell if the wastegate flapper is hitting the downpipe without at least disconnecting the actuator arm(by the downpipe).
Problem with this is it's a pita to get to! You simply can't see it,only feel.Getting off maybe ok, but putting it back on, jeeez.
Not impossible though.
Didn't folk warn you already about eBay down pipes? Pot luck really if you have issues with wastegate flapper(Yes japspeed sell the same as the eBay bits).
On q separate note do you have the support plate fitted to the downpipe?
There is a good reason why people do this mods at home because of issues with product quality.
Your mate/mechanic couldn't have known the flapper was hitting the downpipe unless he removed the actuator arm to test or applied 7psi to the actuator.Both of which I highly doubt he did.



I'm quite interested in what Jims said here, my car came with what i think is an ebay downpipe already on it.

One of my first fixes on the car was to release a jammed wastegate because of these down pipes.

I've since replaced the gasket, and plan on fitting a 2nd as I'm led to believe this helps with this problem.


Quite interested in how you remove the actuator arm? I assumed it was fixed at both ends?



Also would be interested in finding out about this supporting bracket.


I tried blowing into my WG actuator to see if i could make it move



Re: 15psi after replacing cat with 3" downpipe
I'm only talking about removing the arm from the flapper.
The other end is fixed at the actuator essentially.

At the flapper it's simply pulled and slips onto a tab
(on the flapper) then a c clip holds it in place.
By pull I mean you need to overcome the spring pressure to yank it onto the tab.

This is why things are tricky because you can't see what your doing.
If you can apply 7psi to the actuator to get it off and on I'm sure things would be easier.

Any downpipe should have a support plate.
Less so one with a flexy, but more so one without due to engine and exhaust movement pulling and pushing on the pipe all the time.
Plenty of non flexy downpipes have cracked due to no support plate.
Google it, gts Chris sells some.
Or at least he used to.

The other end is fixed at the actuator essentially.


At the flapper it's simply pulled and slips onto a tab


By pull I mean you need to overcome the spring pressure to yank it onto the tab.


This is why things are tricky because you can't see what your doing.

If you can apply 7psi to the actuator to get it off and on I'm sure things would be easier.


Any downpipe should have a support plate.



Google it, gts Chris sells some.


Re: 15psi after replacing cat with 3" downpipe
You can apply pressure using a ebay
£4.50 footpump as shown here
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http://vid948.photobucket.com/albums/ad ... e_test.mp4

This is a must have in my book for testing



Kev.





This is a must have in my book for testing





Kev.

Re: 15psi after replacing cat with 3" downpipe
So from that video, what is getting stuck? The actual wastegate flap, or the arm's joint trying to move to open the flap?
Re: 15psi after replacing cat with 3" downpipe
The flap hitting the downpipe and not opening enough.

Re: 15psi after replacing cat with 3" downpipe
What would I need to trim down the flange?
Re: 15psi after replacing cat with 3" downpipe

mr299ron wrote:So from that video, what is getting stuck? The actual wastegate flap, or the arm's joint trying to move to open the flap?


The video is just showing you how an










Kev.

Re: 15psi after replacing cat with 3" downpipe

mr299ron wrote:What would I need to trim down the flange?


Take the pipe off, place a Toyota gasket, not the one that may have come with the pipe or any you find on ebay, and you will see the part that needs cutting away, cut it away.

Designer for turbo set ups on F1 cars, and Nitrous Oxide Systems of the USA in the 80s