Maggie Bypass problem
Former Vendor
Joined: Jun 2009
Posts: 49
Likes: 0
From: Ventura CA
The numbers all calculate out to ~9psi... you are correct you will see low (no) boost #’s with the bypass open.
The knock retard and low boost issues, points to a hardware issue?
You have pictures of it on the dyno?
The knock retard and low boost issues, points to a hardware issue?
You have pictures of it on the dyno?
Thread Starter
Racer
Joined: Jan 2009
Posts: 393
Likes: 14
Knock was not a hardware issue, I'm happy for that! After many hours of car's misbehaviour the dyno guy rewrote the whole operating system and after that the problem got away! It put down 550hp/680Nm without knock issues. I guess its like playing with Microsoft products, there is just no sense but somehow they either work or won't work.
But boost is still a problem! That run was with only 4,3 PSI. I'm still missing 5 PSI somewhere.
I have also meth system installed but it wasn't used yesterday because of enough problems in tuning without it.
edit: Above 6000 rpm it goes lean, 42 lb injectors are wide open at that point. I have a Magnavolt and 420 Walbro. I made a return line and I have a adjustable pressure regulator. I guess the injector is ok for this power level but I need more pressure?
But boost is still a problem! That run was with only 4,3 PSI. I'm still missing 5 PSI somewhere.
I have also meth system installed but it wasn't used yesterday because of enough problems in tuning without it.
edit: Above 6000 rpm it goes lean, 42 lb injectors are wide open at that point. I have a Magnavolt and 420 Walbro. I made a return line and I have a adjustable pressure regulator. I guess the injector is ok for this power level but I need more pressure?
Last edited by Juhatee; Oct 1, 2010 at 03:46 AM.
Thread Starter
Racer
Joined: Jan 2009
Posts: 393
Likes: 14
Ok, now I'm being told this low boost might be because of the engine breathing better ("consuming" more air). This sounds reasonable but I'm still unsure.. Could this make so big difference? I'm only halfway on my boost.
Former Vendor
Joined: Jun 2009
Posts: 49
Likes: 0
From: Ventura CA
That’s good to hear… I was starting to get a bit worried for you?
Do you have the dyno graph? What is the boost curve doing?
What does your belt routing look (pictures?) like, is it exactly like the vehicle? What is the tensioner doing @ WOT? We do have a stronger tensioner?
No, the boost calculator does not ‘lie’ that much… unless you have an inlet restriction, lots of cam overlap (never seen 5psi worth), belt slip, etc…
Do you have the dyno graph? What is the boost curve doing?
What does your belt routing look (pictures?) like, is it exactly like the vehicle? What is the tensioner doing @ WOT? We do have a stronger tensioner?
No, the boost calculator does not ‘lie’ that much… unless you have an inlet restriction, lots of cam overlap (never seen 5psi worth), belt slip, etc…
Thread Starter
Racer
Joined: Jan 2009
Posts: 393
Likes: 14
I learn every day.. The logged MAP value is not actual boost value. Had to do some testing to see that above zero pressure it was not right. I have a Cobalt 2 bar map which I thought was supposed to be remapped to original ecu but there was no chart to change at all. Just a chance to choose a 2 bar map. That chioice didn't get the real pressure to graphs, only an average of original map maximum and the real pressure, which in this case was 4,3 PSI. The real pressure was 7,8 PSI!
At least much closer to the attempted level of pressure.. Too bad the power output would have been more in line with that lower pressure
I still have a knock issue, but only at low rpm. Below 2000 rpm we must use so little advance that I won't gain anything from the blower. Above that there can be used more ign advance so the power goes up nicely from there.
At least much closer to the attempted level of pressure.. Too bad the power output would have been more in line with that lower pressure
I still have a knock issue, but only at low rpm. Below 2000 rpm we must use so little advance that I won't gain anything from the blower. Above that there can be used more ign advance so the power goes up nicely from there.
Former Vendor
Joined: Jun 2009
Posts: 49
Likes: 0
From: Ventura CA
Thread Starter
Racer
Joined: Jan 2009
Posts: 393
Likes: 14
In fact the main issue now is broken diaphragm in bypass actuator (I broke it myself today..) I sent e-mail to your company to get new one asap.
Former Vendor
Joined: Jun 2009
Posts: 49
Likes: 0
From: Ventura CA
Yes, I'm assuming (with out data logs) that your injectors are too small. It all depends on fuel pressure, AFR, duty cycle, etc...
For the acuator replacment, your better off calling us, but I know how that can be an issue for some people when @ work.
For the acuator replacment, your better off calling us, but I know how that can be an issue for some people when @ work.
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