Fuel pressure?

phunk

Yes under boost it will surely work consistently. But its the low load cruising that made me decide not to follow through with building external regulator 1:1 ratio based fuel system kits for these cars.

What about under this circumstance as an example. And yes, I understand closed loop fueling SHOULD be able to handle this situation, but it still feels improper to me.

Say you are cruising down the tollway, and the VVEL is maintaining a 0/0 vacuum environment in the intake manifold. If you simply tap on the brake but do not lift throttle. The system instantly switches to throttle control and generates vacuum to operate the brake booster. But instead of holding on the brake, it was just a mere tap (for whatever reason). Now I know this test circumstance is more like searching for a inherent flaw than it is an actual driving condition... But, we have now created a situation where we have gone from no vacuum to engine load specific vacuum. The fuel pressure will instally drop due to vacuum, and then within a few moments it switches back to VVEL load control and fuel pressure will raise.

Like I said, I know thats a strange set of conditions and not very likely to occur in regular driving... but that set of circumstances alone was what told me that I cannot depend on the VVEL system to give me a consistent connection between actual engine load and manifold vacuum. I stopped trying to theorize other conditions where this could occur... but I certain there has to be some others.

But if the car seems to drive and cruise without issue regardless, then I suppose my concerns are exaggerated for the situation.

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