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Hussein's 1998 V70 Xr : The Force Awakens


lookforjoe

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If airflow and AFR remains constant, IDC will increase to 89-90% at 7500 rpm. If you get more air or run a little richer, it's gonna be even higher IDC. Past 80-85% at those RPMs, the injectors are basically saturated anyhow; there probably isn't enough time for the pintle to close all the way. You'd have to know the actual rise/fall time of the injector to be sure, but I'd say you're running dangerously close to the limit of those injectors.

That intake manifold looks pretty good. I gotta get in touch with Nathan soon :D

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If airflow and AFR remains constant, IDC will increase to 89-90% at 7500 rpm. If you get more air or run a little richer, it's gonna be even higher IDC. Past 80-85% at those RPMs, the injectors are basically saturated anyhow; there probably isn't enough time for the pintle to close all the way. You'd have to know the actual rise/fall time of the injector to be sure, but I'd say you're running dangerously close to the limit of those injectors.

That intake manifold looks pretty good. I gotta get in touch with Nathan soon :D

I wonder if I should raise the base FP? Would that lower the duty cycle? I'm running these @ 3.5bar (700cc) now, I could raise it to 3.8. Otherwise, I'll have to look for 750cc injectors. I would expect that once I have the new manifold & then the exhaust header, that I will only hit the ceiling sooner, no?

EDIT: Maybe I should just lean out the upper load cells to bring the AFR's up somewhat?

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I wonder if I should raise the base FP? Would that lower the duty cycle? I'm running these @ 3.5bar (700cc) now, I could raise it to 3.8.

You have the same adjustable FPR as I do. Definitely raise fuel pressure. More fuel delivered should equal lower duty cycles.

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I wonder if I should raise the base FP? Would that lower the duty cycle? I'm running these @ 3.5bar (700cc) now, I could raise it to 3.8. Otherwise, I'll have to look for 750cc injectors. I would expect that once I have the new manifold & then the exhaust header, that I will only hit the ceiling sooner, no?

EDIT: Maybe I should just lean out the upper load cells to bring the AFR's up somewhat?

You have the same adjustable FPR as I do. Definitely raise fuel pressure. More fuel delivered should equal lower duty cycles.

Yes raising the FP will essentially lower the duty cycle. You will have to adjust your table though. Why not go to 4 bar? ME7 runs at 4bar.

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Yes raising the FP will essentially lower the duty cycle. You will have to adjust your table though. Why not go to 4 bar? ME7 runs at 4bar.

I believe ME7 is actually 3.8bar, that's why I suggested it. Adjusting the table is the easy part, I can simply calibrate the whole map leaner in 1% increments to get 14.7-15.2 base AFR.

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Raised the base FP to 3.8bar, recalibrated the fuel map - 5% leaner. Did a quick couple of pulls to see what happened with IDC - this one is in 4th, constant uphill grade

Need to refine fuel levels after the RPM rescale - got a horrible spike @ 6800rpm....

Picture2-10.png

Picture5-2.png

duty cycle has dropped to 82% @ 7200rpm

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Thanks for the tip, but that's only 3" piping - that's smaller ID than what I'm using :D

Ok I figure you might be using a little bigger ID. You seem pretty good with fabbing stuff could you make one of these with a 3.5 or even a 4" ? or is the maf sensor itself unable to do it?

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Ok I figure you might be using a little bigger ID. You seem pretty good with fabbing stuff could you make one of these with a 3.5 or even a 4" ? or is the maf sensor itself unable to do it?

I could try fabbing a 3.5" housing. The problem is that throttle response suffers going off idle the larger the housing. Not so bad with the more aggressive cams, I've found, but still there. The problem isn't the sensor (I'm already using one from an Audi A8, makes no difference) it's the ECU presets, it just doesn't acknowledge anything over 231g/s.

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Are you still using the stock subframe bushings? I just ordered a set of CJ's Delrin versions that I need to install ASAP! I can feel the everything move when I thrash it around turns and heavy dips on the hiway.... :ph34r:

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