Pulse and Glide - Vacuum

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I've got a vacuum gauge tapped into where the fuel pressure regulator is.
I've been using pulse and glide for a while now, and I've had a thought based on something recent I read here, which was to not go into 'boost' as that's just waste.

Does this really apply to pulse and glide?
- Do you want to get up to speed as quickly as possible to glide (throttle 70% or so - reduce restriction..)
- Do you want to get up to speed, but maintain vacuum (say 2-5 inHg - maintain little restriction) ?

If I floor it that vac gauge goes right down to 0, but if I follow it, I can get it to stay around 4 and get over speed and glide.

I haven't been looking carefully at it, so can't say for sure, but my O2 gauge looks to go into closed loop if I maintain slight vacuum). The downside is it takes a little bit to get the speed up.

Which is better?

[user removed]

You want the lowest vacuum without loosing your closed loop (02 still cycling). Probably about 2 inches, but I never had both gauge readings at the same time to verify the lowest possible vacuum reading where you lost closed loop. It could vary from engine to engine so test it for yours and let us know at what vac reading it occurs. Some systems may not go open loop without the TPS at max or very close to max. You can get vac readings vey low if you use higher grears for acceleration, even with fairly low percentages of throttle position.

regards
Mech

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Yeh, that's what I thought it'd be.

I can't see 0 through to 5 on my gauge cause of where it's positioned, but the LED bars on the O2 gauge cycle fairly well compared to trying to get to speed as fast as possible.

I think it's cause of the mapping in the ecu that it advances ignition timing when in closed loop.

It'll be difficult to tell just on the O2 led bar graph - it's could be a volume thing as well (as I hold throttle, RPMs continue to increase). O2 cycles fairly quickly, and it'll do that in open loop too - right? Unless I'm missing something..

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I reckon it works!

My last tank is the best ever, first time it hit 5xx as well..
All I've realistically done in the last few tanks is back off on the throttle on my pulses a bit (I used to go 'full throttle'), removed the intake path to the bonnet, and removed mud guards.

I was fairly careful (but do know I wasn't all the time), to keep vacuum around 5in, and make sure O2 bar was pulsing fast when trying to "Pulse". WIth my glide being the usual glide down to below speed and pulse back up.

Something i've noticed is that in closed loop power builds faster, ECU must be doing something, or it's the EGR ? (another thought).