ETA 2.7 Engine - Injectors

[silly]

Sticky thanks for the comprehensive txt.

Do the std injector sizes work or do you need another type? Am building a 2.7 with bigger throttle body gas flowed head , long life headers etc

silly in NZ

[march109]

I've been told the standard injectors are fine unless going for massive silly power that a N/A 2.7 wouldn't give.

[Ant]

use 325i injectors, intake and TB with the 3 bar reg and all shall be well.

use a 173 ECU setup , it will need chipping to suit the longer stroke crankshaft dude

[antony]

I'm also building a 2.7 in NZ

Where abouts in NZ are you?
Are you on bimmersport?

[Andyboy]

Eta injectors are the same as the 320i - past 4000 rpm they just won't fuel a proper 2.7 and it'll run as lean as hell.

As Da Antman says, twentyfive injectors, manifold, TB and AFM.

[reggid]

i was under the impression that the ETA were low impedance and flow similar to the M30 ones ~19lb/hr.
The late b25 are high impedance ~14.5lb/hr and won't satify the demands much past 200hp (theory suggest lower than 200hp) with standard fuel pressure. i would look for something larger than the stock B25 and get M30 ones.

[Andyboy]

ETK lists both early and late 2 litre and 323i injectors as being the same, as does the official Bosch parts book. Some 1982 635CSi's used the 126 (83-85 high comp Eta) injectors for 3 months in 1982. No 535i or 735i ever used 2.0/2.3/Eta injectors.

[reggid]

ETK lists both early and late 2 litre and 323i injectors as being the same, as does the official Bosch parts book. Some 1982 635CSi's used the 126 (83-85 high comp Eta) injectors for 3 months in 1982. No 535i or 735i ever used 2.0/2.3/Eta injectors.

I didn't mean the ETA and M30 ones were the same just they flowed the same or so i have seen people claim.

However a sorted 2.7 would want more than the m20b25 ones can deliver i would think. Whats the duty cycle of the 325i ones at 170hp & 13.5:1 AFR?

The m20b25 bosch are 0 280 150 715 and are blue rated at ~149cc/min @ 3b
M30 ones are Bosch Part Number: 0 280 150 203, 185 cc/min

[Ant]

the stock B25 715's are good for 220 HP, anymore and you can see the AFR go lean regardless of what you do with the mapping, more fuel pressure can gain a few back but its not my preffered method.

duty cycle iirc @ max rpms/170 hp was around 87% iirc. on stock 3 bar reg.

all the older inj are low Z units and must not be swopped into a motronic car unless you use a flyback resistor pack( volvo like to hide these ) on the ground triggers from the ECU.

( I realise Reggid and A/boy dont need the egg sucking lesson
)

[Andyboy]

I didn't mean the ETA and M30 ones were the same just they flowed the same or so i have seen people claim.

Well that's some claim! 2 litre injectors are just about enough for 170 bhp which is what the C1 2.3 put out using stock 126 squirters - I wonder if it would have done more power with bigger injectors? My 2.7 engine in my old C1 2.3 was underfuelled at the top end and higher fuel pressure didn't really sort it. It will probably stay on LE Jet to keep it looking original but will have to run 2.5/2.8 M30 injectors from an E28.

[Ant]

pop a squirt on there Andy, the purists would never know if you gutted the AFM out

would go better 100%

[Andyboy]

Ha! Just a matter of building the sodding car first. For the last 12-18 months it's been a painted rolling shell with nowt but a wiring loom. 528i injectors will do the job okay, just set the idle mixture and as long as it goes okay and does 20 mpg av, that'll be okay.

Is the 'Pina C2 being restored then?

[Ant]

C2 is getting intimate with the grinder yes

not much to do, but I'll leave NO stone unturned.

[reggid]

the stock B25 715's are good for 220 HP, anymore and you can see the AFR go lean regardless of what you do with the mapping, more fuel pressure can gain a few back but its not my preffered method.

duty cycle iirc @ max rpms/170 hp was around 87% iirc. on stock 3 bar reg.

all the older inj are low Z units and must not be swopped into a motronic car unless you use a flyback resistor pack( volvo like to hide these ) on the ground triggers from the ECU.

( I realise Reggid and A/boy dont need the egg sucking lesson
)

how do you get 30% more power from 13% more fuel? What AFR was the 87%?

[Andyboy]

C2 is getting intimate with the grinder yes

not much to do, but I'll leave NO stone unturned.

That's what I'm doing with the Chrome 320i. It was at the stage where another winter or two would have killed it. So cutting out all the nasty stuff, new metal, zinc primer and Waxoyl when it's painted. Should be a nice turd.

Back on topic - Eta injectors are useless for 200 bhp. You won't even GET 200 bhp. 325i injectors are known to work well up to at least 210 bhp. The C2 2.7 gave 210 bhp on 325i injectors. Above that you need to be looking at M30 units.

[silly]

Thanks for the info guys

Interesting- dont want to get this bit wrong and get robbed of HP or run the bugger lean at top end - not that I'll be running it there all the time .

100km/hr max speed here in godzone.

If I fit the bigger M30 injectors will the car have a tendency to run richer at low speed or idle and maybe wash the bores or will the ECU remap adjust the fuel mix for this? Presume it will?

Presume also if yer fangin it the gas curve will go up as well as the HP which I can live with.

Silly in NZ

[Ant]

the M30 injectors will not just drop in dude, you must tell the ecu there's more flow, so indeed a remap to suit.

if you swop to the later moronic I can supply a chip to run the 2.7 on std m20 b25 injetcors without issue, unless you break the 220 HP mark.

[silly]

Ant

yep -am doing a remap of the ECU using mapecu ltd here which is a piggy back CPU - have a look at mapecu.co.nz

engine so far:

325i block (decked) with 2.7 cast iron crank lightened polished

130mm ETA conrods polished

325i mahle pistons

325i Head std valves etc but gas flowed & ported

272/272 cam

map ECU computer system

longlife headers

K&N

Full engine and drive train balance

silly in nZ