Hi,

Will be going for remapping soon when I sort out other problems with my car but question is,

On a previous mapping session whilst boost solenoid was set to nothing the boost started rising above actuator opening pressure to over 1 bar at a certain point as the revs increased.

How can I get a good solid boost level say 1.35bar without getting overboost and not set it too low and then not make the target boost in certain conditions?

Turbo is td05/06 20g
3 port solenoid

I wanted to run 1.3, 1.35, 1.4 bar absolute max and not have it go above this as it may be too much for the engine to cope with.

Thanks


George

 

wastegate porting

 

I thought they were fairly well ported anyway, there's not much material left around the flap bit?

George

 

A decent ECU or boost controller will do this for you. The only time you cant have the boost you select is if the turbo (on a low setting) boost creeps past the high setting, ie if it is set for .8 bar and hits over 1.4 bar then the controller will not be able to reduce it below 1.4 bar.
If you only creep to say 1.1 bar then the boost controller will be able hold a flat line boost at anything over this level.

Andy

 

what do you mean by "the solenoid was set to nothing"?

Is it plumbed in correctly?

They can creep with some downpipes. Also check the actuator doesn't have too much preload on it. If it's been untouched since andy did it then htis should be okay.

Paul

 

I had this with my Stock Sti v3 after I had the Blitz boost controller fitted to cure acute fuel cut (1.6 bar over boost)
Power Eng set it to 1.25 as a 'safe' setting, and it crept to 1.31 after 2 months use and settled at 1.31 where it's been for 18 months, rock steady.

As you know Andy, the 20g will soon be in place and the 3 port sol I've just found (are they rare? took some finding). I hope with the Apexi FC in place I can remove the Blitz before you map it to a zillion bhp!

Incidentally, ran the Sti on straight Optimax for a year at 1.31 in hill climb conditions and all was well.

911

 

Hi,

Andy, It's on the Gems ecu

Paul, its the same car that I have been having lots of trouble with ECU wise.
While Pat was mapping he set it to a level where it only should have made actuator pressure .7 bar or so? and it went up to over 1 bar as the revs went up.

Only set at 1.2bar at the mo which it holds most of the time but sometimes goes 1.3 or more and have seen it at 1.5 higher up the rev range. Seems the higher it revs the more boost it makes

Could it be the splitter part in the APS downpipe? should I get the grinder on it and take it out?

Should the 3port click constantly when ignition is turned on but engine is not started? If you start engine then switch off it doesnt?

George


George

 

okay that sounds like real creep and not so much of a control issue. Yes your splitter could be making it worse, the other end of the spectrum is open neck downpipes which in my experience have trouble holding boost at the top end on a td05/06 turbo.

The wastegate porting may be able to be improved upon, in paticular the blending of the passage into the wastegate hole itself.

Paul

 

I recommend removing the splitter, if you look at where the wastegate gasses eject, a splitter is a major obstruction and leads to boost creep in most cases.

I don't think the 3 port should be clicking with the engine off, it has no reason to !
It certainly doesn't on OE or Apexi.

Andy

ps 911 - stop worrying

 

I've learn't to worry about my Sti, had more trouble with it than my trusty old 911!
Mind you, 3200 cc is still quite a bit slower too.
911

 

Cheers guys, I will take the splitter out and try and get a bit more material from out of the wastegate hole and have another try.

Thanks for the advice

George

 

I'd just take the splitter out and try that first George, if you open the wastegate too much you can struggle to hold boost at higher rpm, its a fine balance !

Andy

 

Hi,

Ok, i will remove splitter first and try it.

George