M20 AFM to M30 AFM with 19lb injector questions

[92 mtechnic cabrio]

Noobs, you can mount an M20 airbox to an M30 AFM. Just get creative.

BTW I didn't, I have a cone + heatshield. But I know several local guys who have done it.

Precisely, I think it requires drilling two or three holes to properly fit the M30 AFM on an M20 airbox, that's what I'm doing.

Way better than a cone + heatshield.

Just be sure to use some kind of RTV sealant as a gasket when you mount the AFM to the airbox.

[B2702]

Nice and would you need to have the 19lb injectors?

[p0cket penguins]

yes you need 19lb injectors

[CorvallisBMW]

what about 17lb injectors?

[E30_fiend]

the reason a lot of people choose the 19lb injectors is because that was the size injector origionslly paired with the m30 AFM.

[z31maniac]

Wow 7 rwhp, might have to actually look into this mod now.

[CorvallisBMW]

the reason a lot of people choose the 19lb injectors is because that was the size injector origionslly paired with the m30 AFM.

Good to know. I just had my 17s rebuilt, so I'll probably stick with them. I may not even bother with the m30 afm swap unless I can find an 027 one for good price.

[kamotors]

not trying takeover the thread but, i just used an m30 AFM with stock injectors and the car felt really good, but the check engine light kept on coming on with fault code 1222.I live at pretty high elevation so i'm not sure if its running lean. i drove about 3-4 miles with it and the check engine light came on repeatedly so i just swapped the old one back in. did i just need to drive alot more?

[92 mtechnic cabrio]

Wow 7 rwhp, might have to actually look into this mod now.

That's actually combined with the stroker kit.

You will probably see 2-3rwhp gains

[p0cket penguins]

We have a ghetto or budget stroker in our 30, with a cam upgrade (previous owner told us, ill check today). Inititally the car was running so rich that our HC emission was 7x the required amount in mass. After changing the O2 sensor, we decided to mount the m30 027 serial number AFM. The car didnt like it at all and ran terrible. Check engine came on and it was just running wicked lean. The next day we install rebuilt 19lb mustang injectors and after a 10 min adjustment period the car idled much smoother and didnt seem to run out of power at the top end as easily. Before we weren't able to chirp the tires between 2nd and 3rd but after this mod it is quite easy.

chris

[E30_fiend]

Well there's a good reason your motor was running lean pocket penguins, you were bringing in more air with the same amount of fuel. So, more air than stock + the same amount fuel= lean condition. Now more air than stock with a good ratio of more fuel= and moderate, slightly rich condition. I passed emissions with the 19lb injectors and my M30 AFM. There is no problem with it.

And kamotors,

Yes you needed to give your car more time to adapt. When I did mine I installed it and mounted it and then I let my car idle for 20 minutes. After that I drove for about 30 minutes letting it get used to WOT and stop and go as well as smooth acceleration.

Your car just needed more time to adapt. But as long as you have the M30 AFM and the 19lb injectors you should be fine.




Taylor

[p0cket penguins]

Well there's a good reason your motor was running lean pocket penguins, you were bringing in more air with the same amount of fuel. So, more air than stock + the same amount fuel= lean condition. Now more air than stock with a good ratio of more fuel= and moderate, slightly rich condition. I passed emissions with the 19lb injectors and my M30 AFM. There is no problem with it.

And kamotors,

Yes you needed to give your car more time to adapt. When I did mine I installed it and mounted it and then I let my car idle for 20 minutes. After that I drove for about 30 minutes letting it get used to WOT and stop and go as well as smooth acceleration.

Your car just needed more time to adapt. But as long as you have the M30 AFM and the 19lb injectors you should be fine.




Taylor

yup exactly why I upgraded the injectors

[Mystikal]

Yeah, I passed emissions with 17.5lb injectors, M30 AFM, and the MarkD chip. Cat had like 375,000km (232,900mi) on it too, lmao.

[CorvallisBMW]

Yeah, I passed emissions with 17.5lb injectors, M30 AFM, and the MarkD chip. Cat had like 375,000km (232,900mi) on it too, lmao.

Good to know i can run an m30 afm with my 17lb'ers then. I'll try and track one down.

[nando]

the reason a lot of people choose the 19lb injectors is because that was the size injector origionslly paired with the m30 AFM.

it's more like 19# injectors are cheap and plentiful since they came on like a billion Fords from the 80's through present day. I think M50 injectors are a better size for a relatively stock M20, but 19#s were too small for my stroker on both motronic and standalone - motronic ran a little lean, MS ran right but at 90%+ duty cycle. $0.02