Boost dropping = Cracked Mani???

[supernova]

Just noticed today that when I go over 6k revs, the boost starts dropping off. I have upped the boost to 0.9 bar using a HKS actuator. Also got a Jam ECU, FMIC, decat among other mods. When going over 6k revs, the boost drops to about 0.6-0.7 bar. Does this mean my mani is cracked? ( i got stock mani) Or does it mean something else? Thanks.

 

[simon]

It could be cracked as this is common to the stock mani. When my one was cracked it made a hissing sound when it was cold. ( as the gass was leaking by) ,and when the car warmed up to temp the metal expanded enough to seal the crack. I was loosing boost at higher revs (ABOUT 0.3BAR) when the engine was at temp.
Its a pain in the ass job to change,with the fasteners been subjected to so much heat.

Good luck with it!

 

[Nick@TD.co.uk]

Mate, if its the stock CT9 still they do that anyways, all CT9's drop boost at higher rpm's basicly just due to the size of the turbo, it struggles to maintain the boost lvls at higher rpm's mine does very similar but i have managed to get it better by relocating the filter to the front bumper and getting rid of the restrictive EFI Intake pipe

 

[supernova]

Yeh I still got the little CT9, where could i get a good replacement for the EFI pipe? you got any pics of yours?

 

[tosa2tosa]

Mate, if its the stock CT9 still they do that anyways, all CT9's drop boost at higher rpm's basicly just due to the size of the turbo, it struggles to maintain the boost lvls at higher rpm's mine does very similar but i have managed to get it better by relocating the filter to the front bumper and getting rid of the restrictive EFI Intake pipe

do u know a gud place to get as 90 degree pipe to mount it in the bumper?

 

[Nick@TD.co.uk]

do u know a gud place to get as 90 degree pipe to mount it in the bumper?

Ive got a 90deg bend lying around that i tryed to fit but it doesnt fit with the WEPR fmic kit, if you have a fmic that loops back over the exhaust mani then it will fit.

 

[Starbus]

Ive got a 90deg bend lying around that i tryed to fit but it doesnt fit with the WEPR fmic kit, if you have a fmic that loops back over the exhaust mani then it will fit.

At the weekend i removed that loop over the exhaust but still retained the 90 degree bend so it should fit anyway?

As for the boost dropping off it could be down to anything thats restrictive at high end. The turbo will be out of is efficiency but it should not drop that much.

I have a stock manifold should you need to try 1.

 

[TurboDave]

A normal 90 degree does fit but it is an absolute nightmare to get past the wepr fmic I moved my radiator over slightly to help. .

 

[Jay]

Is this the same setup you were using on your old glanza Kev?

Just curious to know what boost you were running..

 

[supernova]

yep, pretty much same except didn't have decat on old one. Also running about 0.9 bar on old glanza. Don't know if the boost was dropping off as well in the old one though. Anyone got any pics of their relocated filters for more air? Anytraders have any products that replace the stock EFI hose?

 

[Jules-B]

over 6 k??

i rarely take my glanza over 5.5!!!!
is a standard engine though

 

[MAD_MO]

jules your a big wuss

 

[Jay]

Your old setup:

Turbo cracked:



Head cracked:



Needless to say the manifold is cracked badly too. None of this is impact damage by the way - it's heat related.

 

[supernova]

Oh really, didn't really feel anything wrong with that car, was pulling pretty well i thought... But i do have a feeling that one was ragged in JP and also the place i got it from turned out to be a really dodgy place...

 

[Jay]

There was plenty of soot around the crack in the head meaning that it had been like that a while mate, ct9's don't cope well with high boost so take it easy with your current one. History can repeat itself!

 

[supernova]

Well i only had the black on for 4 months before my mate crashed it so probably like that when i got it... Yeh i do have the new one set at 0.9 bar, but i drive sensibly ( ) so rarely do that boost so hopefully i be ok

 

[widdo]

mine does this too, gets to 0.6 bar then starts to drop once above 5000rpm

 

[supernova]

So i suppose this is norm for little CT9 then.... But my car does feel real sluggish lately, but that could be just me!

 

[Ady]

yeah mine does it too.

i started a thread about the problem like a week ago!

 

[supernova]

Yeh just had a read through it. But seems like everyone is experiencing different things, no definite answer... Some have same problem, some don't have the problem....