bmw m635csi fuel injector upgrade?

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M6 chris

bmw m635csi fuel injector upgrade?

Post by M6 chris »

I have my throttle bodies in bits at the moment and the injectors removed just wondering if there is an upgraded injector recommended to fit or are the originals up to the job and is it just best to get them cleaned?
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slofut
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Location: SW Ga

Re: bmw m635csi fuel injector upgrade?

Post by slofut »

M6 chris wrote:I have my throttle bodies in bits at the moment and the injectors removed just wondering if there is an upgraded injector recommended to fit or are the originals up to the job and is it just best to get them cleaned?
Someone should chime in here, I know I've seen several threads on this and there's a ford injector that's recommended? :-k
Chris Wright

Re: bmw m635csi fuel injector upgrade?

Post by Chris Wright »

M6 chris wrote:I have my throttle bodies in bits at the moment and the injectors removed just wondering if there is an upgraded injector recommended to fit or are the originals up to the job and is it just best to get them cleaned?
My notes show the M635 using th Bosch 201 low impedance injectors and if memory serves, there is no "upgrade" for them (the ford injectors replace the later injectors). Perhaps someone will know for sure?:

Five injectors were used on Motronic system models. All BMW part numbers preceded by 13 64 1 and all Bosch numbers by 0 280 150:
Bosch ...... BMW
- 201 ....... 273 272 - (low impedance) ....... 9/80 - 5/82 ....... Euro 633 & 635 (001 and 002 ECU's)
- 201 ....... 273 272 - (low impedance) ....... 9/81 - 9/84 ....... US 633 (008 ECU)
- 201 ....... 273 272 - (low impedance) ....... all M6/M635 ... (079 and 055 ECU's)
- 126 ....... 273 271 - (low impedance) ....... 5/82 - 9/82 ....... Euro 635 (011 ECU)
- 130 ....... 286 026 - (low impedance) ....... 9/82 - 9/84 ....... Euro 635 (011and 018 ECU)
- 203 ....... 276 149 - (High impedance) ..... 9/84 - 1/86 ....... US & Euro 635 (059 and 061 ECU's)
- 714 ....... 276 988 - (High impedance) ..... from 1/86 ......... US & Euro 635 (059, 061, 150, 179 ECU's)

Substituting low impedance for high impedance injectors will burn up the computer
jpr210
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Joined: Tue Jun 25, 2013 2:27 am
Location: Miami, Fla.

Post by jpr210 »

I've been trying to get to the bottom of this issue as well. My understanding is that the we could use an high impedance injector on a low impedance ECU but not the other way around. The higher impedance injector would draw less current (require slightly higher voltage) which does not tax the injector driver of the ecu as much....being able to use the 4 hole bosch M50's would be great.

Jpr
GazM3
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Joined: Wed Oct 26, 2011 12:55 pm
Location: Melbourne, Australia

Post by GazM3 »

I had an injector guy source some low importance multi holed injectors. They went for slightly bigger capacity for memory 26 lb/hr and I dialed out the excess fuel mixture via tigening the airflow meter spring (needed 9 clicks) with the added benifit of leaning off the air meter the ecu seems to add more timing into the engine.

The benifits are many.
1/ more throttle response and power
2/ much better part throttle running
3/ a little more headroom to add more power in te future.

Can't comment on fuel economy it seems slightly better but I drive it fairly enthusiasticly so its hard to tell
BMW’s
84 E24 M635csi
90 E34 M5 3.6
94 E34 540i/6 SC E85
97 E36 M3 euro SC U/C
97 Z3 2.8 widebody

OTHERS
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M6 chris

Post by M6 chris »

Thanks for the replies it seems as though it would be worth doing as iam going to fit a miller maf with a war chip so setting it up shouldnt be an issue do you have any idea what those injectors came off Gaz off? Do you have a part number? I assume they are a bosch injector?
GazM3
Posts: 1791
Joined: Wed Oct 26, 2011 12:55 pm
Location: Melbourne, Australia

Post by GazM3 »

Sorry I have no part no or nothing. Lots of help I am
BMW’s
84 E24 M635csi
90 E34 M5 3.6
94 E34 540i/6 SC E85
97 E36 M3 euro SC U/C
97 Z3 2.8 widebody

OTHERS
11 Audi S5 3.0 SC
19 VW Amarok V6
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slofut
Posts: 778
Joined: Thu May 30, 2013 1:29 am
Location: SW Ga

Post by slofut »

Guess I'll hit this old thread again and probably start something, but here goes...
An injector guy sold me these last year as upgrade injectors for the 635. They're Ford Part #: F6VE-A5A, 0280155210 used in crown vics.
All plastic orange colored with four holes and bosch type connector, that's all I know, I didn't even research the injector before I bought them. So I haven't used them yet, hell I can't even get the '88 to stay running (no start, probably fuel). But I thought I'd pass the info along for anyone who wants to investigate further. [-o<
Bill
'87 635csi, 5sp man, dk blu on pearl beige
'88 635csi, auto, black on grey
'63 BMW Isetta
'75 XJ6C, 2dr, warm 350
'86 XJ6, th700r4
'75TR6
'64 Olds 88 conv
"68 T120 Bonneville
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