BE5 legacy max boost 11psi ?

[Jono24]

Hi guys,

I've had this car for a while and it never seemed as fast as my old BG5 on the second turbo.

The car is a BE5 Rev. A, with the centre cat removed, a Corazon muffler, and the rest is stock as far as i know. it is a manual with the vf26/vf27 turbos. it has a strut brace, 4 pots, and the centre diff replaced for an earlier version (thanks guys!!!).

I finally got around to putting in a GReddy electronic boost gauge which i installed using the advice off one of the threads on here (sensor is connected like this http://www.clubsub.org.nz/forum/index.php?topic=16078.0).

On the primary i've seen as high as 0.65 kg/cm2 (~9 psi). but on the secondary only ever managed to reach 0.8 kg/cm2 (~11 psi) (this is verified by the memory on the gauge).

I've read you can get bad readings from improper installation of the boost gauge, but the primary seems to register a close to expected reading and the secondary is a lot further off the mark (i'm suggesting that ~10 psi primary/15+ psi secondary is normal). from this i am assuming my installation of the pressure sensor isn't the problem.

I've also checked the CEL codes and just get the constant flashing, indicating no problem.

I'm not sure what's going on here and any help would be appreciated, thanks in advance :-)

[Marky]

My current one made similar boost when I got it, some of the wastegate hoses had been replaced and it was missing a restrictor pill - meant not as much % of air being bled off by the factory boost control solenoid - chalked it up to that. Didn't bother looking into it, just binned the lot and ran a boost tap anyway.

My previous one was the same and ended up being the solenoid being gunked up - ran some brakleen (or similar) through it to free it up and things went back to normal.

At least it's too low not too high!

(the hoses this concerns run in behind the battery, the solenoid itself is tucked riiiight up inside the guard out of sight behind the guard liner)

It worked for me anyway

[Jono24]

Thanks for the reply.

Only just just got to have another look today, could you tell me where you sprayed the brakleen? i see two vac hoses (numbers 10 and 23 on them) going through the inside of the engine bay and into the guard cavity, are these what you were talking about?

you wouldn't happen to know which lines are supposed to have restrictor pills? any idea?

[Marky]

That's the ones I believe there is supposed to be a restrictor between the pressure outlet off the Turbo and the t junction. Don't quote me on that tho!

[Jord]

Yup there will be a white or pink dot marking the location of the pill on the hose coming off the the compressor housing. Feel the hose you will feel if there's a restrictor pill in there.

[Jono24]

Thanks guys, found the pill between the compressor and T join off the primary, hard to even see but felt it in there.

went to supercheap to get some brakleen this morn and none of the cans had the straw attachment, i asked if i could take one of the ones off a normal crc can and they told me that would be theft.... (pissed me off).

anyway, i'll go to repco and get some now....

thanks

[Jord]

Nice. If your feeling keen you can remove the BBOD on the other side and clean out all the vacuum lines and solenoids, I would think the problems would be more related to the BBOD as its the one that controls secondary boost. Here's a how to....

http://www.uklegacy.com/forums/index.php?showtopic=11043

Just make sure you dont spray cleaner into the map sensor...

[Jono24]

thanks for that, looks not too hard

I tried the solenoid which you can't see (behind the battery) doing a similar process (with the green and black plugs connected) but didn't notice any difference.

I'll have a go at this on sat when i get time.

appreciate the help (and the pictures!!!)

by the way, i didn't realise these had a map sensor... why do they use a maf and a map?

[B4 I was 250T]

Quick question- what centre diff does it now have and what difference does it make??

[Guest]

 B4 I was 250T said:

Quick question- what centre diff does it now have and what difference does it make??

Its not a performance related mod its a fix for buggered centre. Common conversion as its easy to find an early buggered gearbox with a good centre. Pre v5/be/bh have a stronger centre.

[B4 I was 250T]

Cool Cheers