Uncontrollable Boost

[ByeByeRB26]

Hi Guys,

I have encountered a problem, and need help!

I have been modifying my car and finally taken it to be tuned

Mods Included are,

Edit

valve springs

Bosch 968 injectors

9psi wastgate

Bosch 044 fuel pump

Intercooler custom plumbing

Air box and battery swap

3 1/2" diffilipo dump pipe with 1" screamer pipe going into hi flo cat and twin 2 1/2" exhaust

The least boost it is running is 17psi even by bypassing the computer it still cant be controlled

it is making over 350RWKW which most ppl would be wrapped about but it is a standard engine and is very dangerous

The tuner has ensured me there is nothing wrong with the wastegate and has suggested that the dump pipe is not designed properly and there is no restriction therefore they cant control the boost and has asked me to solve the issue

Has anyone else experianced this problem with a difilipo dump pipe or even in general tuning

Any advice would be appreciated on how to solve the problem

Thanks

ByeByeRB26

[Muzza]

I'm having simular prob with same mods but exhaust, mine is boost on boost off.

Try a manual boost controler,about $60 by memory. see how that goes.

Are you using edit?

Muzza.

[FPV TRANNY]

Sounds like the actuator mate.I had a modified actuator in and it wanted to run a minimum of 16psi.

Did it start happening when you put it on?

Try changing it back to a stocky to see if that's your problem

[Fat-Tony]

having a free flowing dump might be the problem as the factory wastegate is a tiny little thing and might not be able to control the boost enough as there is no back pressure, but it seems far fetched

[Geeseman]

running high boost you need to modify the actuator swing arm and also port the wastegate so enable higher flow. A turbo shop should be able to help with this.

[Muzza]

  FPV TRANNY said:

Sounds like the actuator mate.I had a modified actuator in and it wanted to run a minimum of 16psi.

Did it start happening when you put it on?

Try changing it back to a stocky to see if that's your problem

←

Good advice. Mite try it aswell.

Muzza.

[ByeByeRB26]

Thanks for the input guys,

I have changed the actuator twice and still no control over the boost, so im pretty sure its not the actuator. its really bugging me as it is at high risk of blowing an engine if driven consistantly on that boost, besides it does not allow me to have any other edit tunes as the boost cant be altered

I modifyed the car in one hit so its hard to pin point what part is causing the problem

Any other Suggestions would be appreciated?

[FPV TRANNY]

  ByeByeRB26 said:

Thanks for the input guys,

I have changed the actuator twice and still no control over the boost, so im pretty sure its not the actuator. its really bugging me as it is at high risk of blowing an engine if driven consistantly on that boost, besides it does not allow me to have any other edit tunes as the boost cant be altered

I modifyed the car in one hit so its hard to pin point what part is causing the problem

Any other Suggestions would be appreciated?

←

What actuator did you change it with.You have mentioned that you have a 9psi wastegate?

Have you used a stock actuator?

[Romulus]

I just finished tuning a XR6T manual with a similar problem. Couldn't control boost over 4500rpm, and boost was steadily rising to around 17psi. It's nice to make 340-350rwkw, but on a stock motor, it's a bit of a gamble.

It definately looks like your engine is over-exhausted. The car that I tuned had a 4" dump pipe, twin 3.5" cats and a single 3.5" system. Front section was too big for the new intake kit.

I had the boost control issue remedied by installing the stock dump pipe and a single 3" cat. Car now makes an easy and reliable 290-300rwkw on 10-11psi.

Edited 11/07/06 10:37 AM by M6 XR6T

[ByeByeRB26]

the exhaust is off the turbo difilipo 3 1/2" dump with a 1" screamer pipe then a 3 1/2" hi flow cat and twin 2 1/2" from the cat to the back

I might have to bolt back on the original dump and then start with an 3 1/2" engine pipe off the origianl ford dumpdump

I never thought having no restriction could be an issue on a turbo car

I still want to make 350rwkw but just not everyday