injectors: newbie q

For discussing injector selection,manifold modifications, throttle bodies, fuel supply system design and construction, and FIdle valves and IACs.
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Yves
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injectors: newbie q

Post by Yves »

Hello,

I'm in the process of gathering parts for the efi retrofit on my chevy.

I calculated that the engine would require 42 lbs/h injectors and the supplier of the manifold suggested bosch injectors.

I see there are several types running from low impedance to high impedance. As far as I understood, ms does not support 8 low impedance injectors... so i'm confined to the high impedance types. Anyone have a correct partnumber for those and what are the disadvantages from low to high impedance ?
Philip Lochner
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Re: injectors: newbie q

Post by Philip Lochner »

Yves wrote:As far as I understood, ms does not support 8 low impedance injectors... so i'm confined to the high impedance types.
My V12 Jag is running on 12 low impedance injectors, 6 per injector circuit. In fact, I have come accross a serious pro ECU that can NOT handle low impedance injectors (in an optimal fashion that is).

Still, if I could choose I would go for high impedance- just to eliminate possible flyback issues.
Best regards
Philip
'74 Jensen Interceptor Mk3 (MS-2 EFI, GPIO + GM 4L60e)
'80 Jaguar XJS 5.3L V12* (MS-2 EFI + dual EDIS-6)
and about 10 others.
FridgeFreezer
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Post by FridgeFreezer »

If you have the choice, may as well go Hi-Z as far as I can tell.

Some cars run low-Z with resistors rather than low-Z and PWM.
73Eldo
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Post by 73Eldo »

What size motor are you running? Fairly stock V8 42lbs would be in the range of 4 injectors and TBI. That 40-50 range seems to be where many of the injectors switch to low z's. Below that the common ones tend to be High z's. But Im fairly new to this so I could be wrong.
73 Cadillac Eldorado convert Fairly stock 8.5:1 500cuin/8.2L
MSIIV3,2.88,relay board, LC-1,Older Holley 670cfm 2bbl TBI w/85lbhr injectors.
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