peak-n-holds

[rr]

Well, yes and no, I answered his specific question, and I thought
you covered the other part quite well. As he does want to go to
the PnH drivers, all should be well in the end... (As long as the
smoke doesn't come out of the injectors first, engines don't run
well on smoke...<g>)

BobR.


Bruce Plecan wrote:
> 
> -----Original Message-----
> From: rr <RRauscher at nni.com>
> To: gmecm at efi332.eng.ohio-state.edu <gmecm at efi332.eng.ohio-state.edu>
> Date: Thursday, March 18, 1999 11:39 PM
> Subject: Re: peak-n-holds
> 
> This must be ignoring the first half of the question asking if OK to run
> Peak+ Holds injectors, on a saturated type driver.  Right?.
> Bruce
> 
> >No, just changing the drivers won't make any difference. Both
> >a P-n-H and Sat driver apply the full voltage across the
> >injector at the start.
> >
> >It's only after the current reaches 4A (P-n-H driver), does
> >the driver chip make a change in it's operation. That is, back
> >off the current to a 1A level (hold).
> >
> >The saturated injector current won't even reach 1A, so even
> >if the time-out circuit is used in the P-n-H driver, it won't
> >make a difference. (This would be relative to a single injector
> >per driver, such as a sequential system).
> >
> >-All of the above is relative to GM system's-
> >
> >BobR.
> >
> >For static testing of P-n-H injectors, use a 10-Ohm/10W resister
> >in series with the injector and a 12 to 14 V P/S. It will open,
> >and the current is limited, so no smoke. Can get them at the
> >local RatShack.
> >
> >Mike Pitts wrote:
> >>
> >> Has anyone ever taken fuel delivery measurement differences
> >> between peak-n-hold and saturated drivers, for the same
> >> injector at the same PW and fuel pressure?
> >>
> >> My thinking is that the P-n-H drivers may open the injector
> >> a little quicker, therefore delivering slightly more fuel
> >> for a given PW.
> >>
> >> Just want to know ahead of time if the fueling is gonna
> >> change when I upgrade my ECM.
> >>
> >> Thanks,
> >> -Mike
> >