for all of those with M30 afm upgrades

[demlotcrew]

If you know your engine is going to make 200bhp at the crank, there is no point sticking injectors in that can flow enough for 400bhp.

Using the 200bhp target as a guide, you need to have some headroom in your injectors, so aim for enough fuel flow for 220bhp

The formula for this is CC flow rate of your injector divided by 5 and then times the number of cylinders to give the BHP capacity of the injectors.

170cc/min 170/5*6 = 204bhp
180cc/min 180/5*6 = 216bhp
200cc/min 200/5*6 = 240bhp

Andrew

[bichmgnt]

...Using the 200bhp target as a guide, you need to have some headroom in your injectors, so aim for enough fuel flow for 220bhp

...

I always thought there should be 20% headroom since (from what I've heard) injectors start to become stressed after hitting 80% capacity. For 200 bhp to be 80% of capacity:

200 = .8x
200/.8 = x
x=250

e30s come stock with 14lb injectors which seems at the very edge of capacity for the engine. What's the cc rating of the 19 lb injectors and how many bhp should it be able to produce?

Steve

[demlotcrew]

I was not aware of that, so yeah its also a possibility.

My point is that hes not even hitting 180BHP so whats the point of such large injectors? and he said hes not touched the FPR!!! :shock:


Andrew

[e30 gangsta]

so yeah can we use m50 injectors? instead of teh 19lb mustang ones?

[Bryson]

so yeah can we use m50 injectors? instead of teh 19lb mustang ones?

yes.


I managed to top out (rev limiter in 5th) a dead stock m20 on a flat road with m30 injectors (19lb/hr) and an m30 AFM a few years ago. That translates to 151mph. Stock ass motor only pulled 143mph (same motor). I have video of the 143mph run but none of the 151 run. 8mph at that speed is a considerable difference I believe, due to drag on our bricks

[demlotcrew]

Where did you get the 151mph figure? GPS?

Andrew

[Bryson]

calculated by tire size and engine RPM, it's the best I could do

[SebSter]

I just picked up an m30 afm and the 19lb injectors, gonna have the installed by the end of the week.


The figures you posted im sure are just increases in the max hp right? How about throughout the rev range. Where does the biggest increase occur?


Also which chips do you guys use? I currently have the MarkD 91, thinking of upgrading it to the 93 depending on how much of a difference it would make with the new injector/afm setup.