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Discussion Starter #21
I ordered these and running them right now. ZERO issues, although I had to calibrate my MAF (it was damaged and was repaired) and runs smooth ( I monitor it with a WB gauge).


SIEMENS INJECTORS

njector type: Saturated
Flow rate: 27lbs/hr, 278 cc/min at 43.5 psi (gasoline)
Length: 3 inches, 74 mm
Diameter: 16 mm
O-rings: Top and bottom, 14.5 mm
Resistance: 14 Ohms
 

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Thanks for the quick reply, that site says they are discontinued now and they are the same offering the replacement for a Lucas D376FA as the Bosch 024U252 -

By my calcs, the Bosch comes out to be 294 cc @ 50.8 psi - so its close to what I read the 3.8L flow of 290cc is rumored to be. The Siemens injectors come out to be 324cc with the same calc. Are you running rich?
 

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Discussion Starter #23
My idle is about stoich 14.7 AFR +/- while going WOT at higher RPM's it goes arround 11.8 or so. Just to let you know I have a performance chip and when I did install the chip I noticed the improovement in power but also found that the whole range of RPM under load/WOT will operate like 1 point AFR richer.
When I go WOT my car exhaust a litle blackish/greyish cloud for a instance and bare in mind my car doesn't have the filter exhaust, I mean the CAT and no 02 sensors.
 

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Diego, I fixed my calc and your injectors look to be right on. After more research I found this page:
RC Fuel Injection

The calc there results in your injectors flowing at 300 cc which is right on for the 3.8.

I might be going that direction, my injector nozzles are really brittle, two of them just broke when I touched them. I'll keep you posted on my search.
 

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Discussion Starter #25
Let us know what you end up buying and how does it perform.
 

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A friend of mine imported a Touring with the b38 engine obviously, and the car has a hesitation.

I had the injectors (the std Lucas ones) tested and after an ultrasonic cleaning session, 3x of the 6x injector's flow rates and spray patterns were all over the place.
So new injectors are on the cards.

Went to the dealer to order the Lucas ones, only to be told they are no longer available.

What to do? Any other BMW that uses an obtainable Bosch injector that is a direct replacement?
Everything I have read so far indicates that the b36 injectors will flow less
 

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Oh and BTW - We never got the Ford ones that was spoken of earlier, but what I read about those are that they are ever so slightly too big and will cause rich running anyway
 

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So, any news for injectors for 3.8?
My injectors are die, BMW says, that probably they don't have new injectors.

What injectors people use? ))
 

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So, any news for injectors for 3.8?
My injectors are die, BMW says, that probably they don't have new injectors.

What injectors people use? ))
Check the link in my previous post, it'll take you to a long list of injectors, with flow rates, impedance, connector type... I've found that M3 injectors have a pretty close flow rate (guestimate 5-7% higher), to my factory B36. Set of 6 M3 injectors I bought refurbished and tested, for about 70USD. Unfortunately, projects flipped around (it's never a good idea to juggle projects, on a limited capacity), so I didn't assemble my engine yet. I won't assemble it in 2020 for sure, but once I do, I'll be able to comment on injector's suitability, for B36 at least.
 

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Unfortunately, it seems that most of the replies are towards the 3.6 which it totally irrelevant.

I have taken it upon myself and the Injector service guy to physically test them.

As we all know, the 3.8 utilises a unique injector from Lucas. No longer available.
The 3.6 uses exactly the same injector as a 3.0 S50 engine'd e36 M3. Bosch 0280150701. Still available new.

I took a set of these 3.6 injectors to the service guy to be compared on the same test rig as the 3.8 ones.
The 3.6 injectors flow roughly 21% more than the 3.8 ones at the same rail pressure. Therefore, they are NOT a direct replacement!

However...... The 3.8 has a 3.5bar fuel pressure regulator, vs the 3.6's 3.0bar.
So if one fits the 3.6 injectors in conjunction with the 3.6 FPR to the 3.8, it balances itself very closely. It comes out to 4% more than stock.
 

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However...... The 3.8 has a 3.5bar fuel pressure regulator, vs the 3.6's 3.0bar.

So, i can use 3.6 injectors on 3.8, but with 3 bar regulator?

I find 270cc and 15.9 ohm (stock 16.2) injector from VW, its very close to stock 3.8 injectors — 0-280-150-905
But i dont know what i need to do. Car in parking.... and cant ride.
 

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Do make sure the length is right... Years ago I spent a lot of time on flow rates and pressures... Ordered the injectors and they were far too short. D'oh
 

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Well I have physically fitted all the 3.6 parts to the 3.8, and it runs great.

Havent had a lambda probe in the exhaust yet, but I pretty sure it will be close
 
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