why is your awesome day RR plots looking like it does? Is the boost fluctuating about? (or wastegate being blown open?)
caveo
Guest
Seems fine on the road , hope my wg aint fooked but i wouldnt be suprised if you see this http://i232.photobucket.com/albums/ee265/caveo/P1000476.jpg
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As you probably know, I've been having boost issues with my VF34 ever since it was fitted. I could pulse the throttle to get the boost to go silly high, then boost would drop off some days. Reset the ECU and it would be back up again (no limp issues). I been through various working N75 valves.
Anyways, I've just fitted an electronic boost controller. I don't know why I didn't do it sooner. Boost is perfect and I can adjust it to where ever I want. No spikes, no tailing off and no issues from one day to the next. I've set boost at 22psi (what JBS mapped it to).
Turbo is sounding good, car is flying. I say junk the N75.
Anyways, I've just fitted an electronic boost controller. I don't know why I didn't do it sooner. Boost is perfect and I can adjust it to where ever I want. No spikes, no tailing off and no issues from one day to the next. I've set boost at 22psi (what JBS mapped it to).
Turbo is sounding good, car is flying. I say junk the N75.
caveo
Guest
jamiebennett81
Guest
N75 is brand new ( wednesday ) take a look @ my RR graph
I am no experts on graphs, but what is going on with that one....it boosts, then tails off and then picks up again?
I am no experts on graphs, but what is going on with that one....it boosts, then tails off and then picks up again?
Well my guess is this:
In mid range the turbo is overboosting hence the 1.7 odd bar seen on the boost gauge and 368lb/ft of torque (I hope you changed your rods caveo
) - guess this is an N75 issue?Then presumably wastegate blows open, but shuts again once pressure has been released
I see your point with a correct map in theory providing correct boost, but this doesn't seem to be the case for so many people regardless of mapper.
Over on audi-sport.net I see posts like this all the time. Older engines like mine having more problems.
Both jabba and CC maps on mine have given unsteady boost. EBC for me has been the only solution to keep the boost constant. Whether this removes variables like atmospheric pressure, temp, maf reading??? I don't know how much the OEM bosch ECUs use these things to adjust boost.
I'm happy with my car for the first time in ages.
I'm using the Apexi AVC-R. I can't comment on whether it's better than other products as it's the first one I've used. Certainly lots of adjustability available with it.
Well my guess is this:
In mid range the turbo is overboosting hence the 1.7 odd bar seen on the boost gauge and 368lb/ft of torque (I hope you changed your rods caveo
Then presumably wastegate blows open, but shuts again once pressure has been released
I see your point, but I think if it was a boost spike that was causing it, you'd more likely see its effect just after max torque...
I think whats evident is the restrictions of the ecu/mapper, making it do things it was'nt designed to do. Older ecu's (Me3.x) have hardware limits which clip your wings more so than on later ME7.x ones..
There's a place for standalone boost controllers, if combined with correct fueling and ignition, but its two independant systems "hopefully" working together mutually well. - "hopefully"
I am no experts on graphs, but what is going on with that one....it boosts, then tails off and then picks up again?
a log of request vs actual and duty cycle would give a clue as to is it control or mechanical (wastegate being blown open)
shame on these RR days you dont get those figures logged.
I think whats evident is the restrictions of the ecu/mapper, making it do things it was'nt designed to do. Older ecu's (Me3.x) have hardware limits which clip your wings more so than on later ME7.x ones..
There's a place for standalone boost controllers, if combined with correct fueling and ignition, but its two independant systems "hopefully" working together mutually well. - "hopefully"
I imagine I've lost a certain amount of failsafe. More gauges now I think. Disapointing when my car was with the mapper for approx 3 weeks
In retrospect a DTA S60 may have been the way to go originally. Live and learn. New map will be with EBC fitted, hopefully strengthening the "marriage", but for now on this turbo it's working.
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