15 PSI

[derK]

so here's my car:

FMIC
2.5" hardpipes
lexus AFM
580 cc PTE injectors
afpr
walbro
3" tanabe
3" BIC DDP
3" test pipe
SAFC

and i'm hitting 15 PSI WITHOUT a boost controller of any sort. How can i lower the boost?? i know the CT isn't all that great with that much pressure.

 

[MDCmotorsports]

Porting the wastegate internally may help.

 

[Poodles]

15PSI is fine IMHO, you're taken out the restrictions, it's a natural raise in boost, not a forced one...

 

[supra_driven]

15 psi is fine for a couple of months on the stock HG. But be ready for that sucker to go if continued at this boost level. Personally i ran 15psi for about a year before the HG poped.

 

[zurud]

Your wastegate broke

 

[OneJoeZee]

Your wastegate broke

What makes you think that?

 

[bountykilla0118]

15 psi is fine for a couple of months on the stock HG. But be ready for that sucker to go if continued at this boost level. Personally i ran 15psi for about a year before the HG poped.

And what ?????????? They are people making 400rwhp on it. I am two years on mine ...... It has been proven its not the OEM head gasket that is the issue it is the torque specs and machine work (if any) that cause the head gasket to let go.

Derk i hope your head and block have been taken care and the head gasket has been torqued down 75lbs+

 

[Reaper Man]

you should be fine- like others have said, sounds like a natural increase in boost.

 

[derK]

yea the engine was rebuilt a while ago with a new OEM HG and ARP bolts torqued to 80 ft-lbs.

 

[becauseican]

Porting the wastegate hole should help control the boost better, you can take about 1/8" off, along with blending in the leading edge of the hole in the turbine housing..............It just goes to show you how restrictive the stock IC, piping and exhaust is.

 

[starscream5000]

A natural increase in boost? Doubt it. Isn't the stock WG spring about 1.0 bar? If that's so, then damn! you have the best flowing engine in the world, so good infact, that you are getting a little bit more boost than the stock spring is rated at. :sarcasm:

Is your wastegate shimmed?

Ninja edit: I see what's happening now, boost creep from the DDP.

 

[doom26464]

you could always try and put more resteriction back in the exhaust. Also I have always pondered this but since fuel cut is determined by the afm and if you wanted to lower the boost Would wrapping a towel around your intake thus creating more of a resteriction thus lowering you boost level? (I know it sounds gettho)

 

[starscream5000]

Been reading in that other thread on air filters, haven't you? :naughty:

 

[Poodles]

even the stock airbox isn't that much of a restriction...

throw a cat on it and the boost will go down, but 15PSI isn't gonna hurt anything...

 

[foreverpsycotic]

15PSI isn't gonna hurt anything...

other peoples pride?

 

[Poodles]

LOL, probably make a few people cry that they lost to an 80's car...

 

[kylefoto]

Your wastegate broke

Are you going to leave any explanation as to how you came to this conclusion?

If his wastegate was broken, it would keep boosting and boosting till he hit fuel cut. Mine broke and I kept boosting till I hit fuel cut.

Like everyone else said, it seems to be a natural cause in increase.

 

[Poodles]

if your wastegate is broken, you wouldn't boost (or get very little boost)

try again...

 

[zurud]

The stock wastegate is rated at 6.5 psi. When it sees more than 6.5 it open. We use shim to tighten the spring and boost controller to manipulate the pressure going to wastegate.

 

[kylefoto]

if your wastegate is broken, you wouldn't boost (or get very little boost)

try again...

O rly?
My rubber boot on mine was ripped off, and I was boosting just fine, in fact, a little too fine. Kept hitting fuel cut.