Hi All,

 

I've finally freed up what I thought was the last restiction on my Z - had a powerflow stainless sytem grafted on by Topgear Burnley and have to say I'm impressed with it. Sounds cool and looks ridiculous (2x single 6" outlets).

 

'Problem' now is that I have great gobs of torque between 3K and 5K but it feels a little flat when flooring it. Dunno if it's just that the masses of torque obscure the top end power but it would be nice to have both....how can I increase the top end power now?? I don't want to lose the grunt that the car now has - it's hilarious. I had been driving it round with gaping holes in the mid section of exhaust for a while - dunno if tha altered the power characteristics much..

 

Car is SE chipped, no cats/freeflowing exhaust, AVC-R, Blitz SUS induction - oh, and it's converted from auto to man. I am aware that the auto cams are ground for torque rather than top end power like the manual cams and that the Auto T25's are smaller than man T28's...

 

Any (sensible) suggestions?

 

Cheers!

 

RobH

Absolute shot in the dark but have you reset the ecu? ;)

LOL - thanks Andy, must have reset it half a dozen times in the last two weeks, s'pose it's still learning though....probably not done 100 miles as yet...

 

PS I still owe you cash for wheels - not forgotten, just embarrassingly poor (thanks to Mr Boosty!)

 

RobH

LOL! No probs m8 ;) Worth a check to see if you're in safety boost too though ;)

 

CheerZ,

 

Andy

AFAIK the AVC-R will over-ride safety boost...

Originally posted by AdamR

AFAIK the AVC-R will over-ride safety boost...

 

Yes, but it can't un-retard the retarded timing that the ECU also introduces when it goes into 'safety boost' mode.. ;)

Oooer! what's this then? - retarded ignition timing in safety boost mode?? I thought it was purely the boost that was cut!!

 

My boost levels are ok - running approx .9 bar most of the time. Will it show up as an error code if I've been or I am running in safety boost mode??

 

Advice appreciated as ever..

 

RobH

Turn your AVCR into setting:off and see if you make more than .5 bar - that'll show you you if your in safety boost;)

ummm...

 

I'm pretty sure it doesn't make .5 bar with the AVC-R off - but then should it anyway with the stock solenoids disconnected? It used to but hasn't since the manual conversion...

 

Either way, what can I do to get it out of safety boost/ignition retard? I'm getting fed up resetting the clock every time I reset the ECU :-(

 

Just a thought, what should happen to the cat temp sensors when the cats are removed - disconnect?

 

just noticed how dumb that looks - I think topgear may have welded the cat sensors into the new pipes...

 

ta!

 

RobH

If there's no stock soleniods then you'll only hit 7psi with no boost controller active, regardless of the ECU being in safety boost or not.

 

Do an ECU diag - if you get a code 34 (Det sensor) then you'll be in SB, engine temp sensor can also cause it.

 

To get you out - fix the prob.. lol :)

 

It's also quite possible to have a code 34 that comes and goes - my old det sensor harness used to flex as you took a corner, and sometimes stick the car into SB half way through a journey.. only found out when I watched the error codes with a ConZult while driving.

 

Cat temp sensors - can be tied up out of the way, or stuck in the new pipes (obviously tieing up is easier), but they shouldn't be disconnected or cut off.

OK, will have a look at that this evening - thanks for the help.

 

Hope it's not the det sensor :(

Yeah - expensive job..

 

Although you can at least bypass it temporarily to check if it fixes things (if your engine expires, I never said that :D although mine ran like that for.. quite a while..)

 

I think you can replace the det sensor by dropping the box, too, if you'd rather not remove the plenum.. Though to be honest, removing the plenum is the quicker of the two jobs IMHO (certainly easier, and lighter than dropping a 'box on your head!). Couple of days work plus parts, you could do it in a weekend ;)

 

(Also a perfect time to renew all the little under-plenum water hoses that perish, and do a few other bits)

 

Just a shame the sensor is £180, and the lower inlet manifold gaskets are almost £50 per side! :(

Oh well...tried that and it's a code '55' - back to the drawing board I guess...

 

One thing I have noticed is the engine 'check' light is on permanently until the car is started - is this normal?? I've removed the autobox control unit - maybe that has something to do with it (?)

 

Cheers!

 

RobH

Does it sound like its running ok with just not much grunt? Could be fuel pump, plugs, fuel pump controller, fuel pressure regulator, could even be a slipped timing belt :eek: have you checked the timing?

 

CheerZ,

 

Andy

Hi Mr Duff,

 

The symptoms are *masses of grunt*:) but little top end :(

 

Everything checks out ok - maybe it's just me wanting more power than I deserve in this configuration. It could just be, as I suspect, that the great gobs of torque between 2.5K and 4.5K disguise the top end power...

 

I have noticed that the boost kind of tails off a bit at higher revs - it has a tendency to overboost at lower revs - up to .95 bar (which is hilarious) and drop off to about .89 bar at about 6K. I've adjusted duty cycle to give a bit extra at peak and a bit less low down but it was too wet to try it this morning.:mad:

 

Thanks to all for suggestions.

 

RobH