tech tip: do not remove injector diffusers

88turboii · 10-15-2008, 09:50 AM

on my new rebuild, i removed the injector diffusers, thinking with they were affecting the fuel flow from my bigger injectors. apparently they are very important, because it ran like crap, hesitations at cruise, AFRs all over the place, etc.

i pulled the injectors and replaced the diffusers and now she runs perfect. very smooth idle, no hesitations at all. apparently they help the fuel distribution in the air, stopping it from just hitting the opposite wall on the intake

just a heads up, incase anybody was considering removing them

10-15-2008, 10:00 AM

Good info.. I knew that if I had removed them it would cause a problem with fuel atomization.. but I never wanted to test the theroy

Whizbang · 10-15-2008, 10:29 AM

what i wonder is if they are still available from Mazda new

10-15-2008, 10:30 AM

yes they are.

RotaryXperiment · 10-15-2008, 10:35 AM

i made sure to put mine in and replace with new orings per my engine builders suggestion.

10-15-2008, 10:51 AM

every time I get into an engien if they wiggle loose I pull them out inspect them for cracks, replace if nessecary and always put in mew o-rings.

Whizbang · 10-15-2008, 10:53 AM

for me they always seem a bit....fragile....from 20+ years of heat cycling. Would be stellar is a nice aluminum reproduction.

need RX7 · 10-15-2008, 02:30 PM

Quote:

Originally Posted by Low Impedance

Would be stellar is a nice aluminum reproduction.

I like.

***ZGN*** · 10-15-2008, 09:01 PM

I pulled my secondary injectors ones when I installed my 1600. runs perfect!

classicauto · 10-16-2008, 11:14 AM

Yeah I have none on my secondaries, primaries ABSOLUTELY.

88turboii · 10-17-2008, 09:12 AM

Quote:

Originally Posted by ZGN

I pulled my secondary injectors ones when I installed my 1600. runs perfect!

sweet, i still left my secondary diffusers out. i wasnt sure if they would cause problems too. Im going to tune it in boost this weekend, so hopefully no problems. im running 1600 sec, 750 pri

Whizbang · 10-17-2008, 10:47 AM

1600s are big injectors though. Not sure how effective the diffusers are at about 3 times the fuel volume

classicauto · 10-17-2008, 12:33 PM

Quote:

Originally Posted by Low Impedance

1600s are big injectors though. Not sure how effective the diffusers are at about 3 times the fuel volume

I'm running a 750/1600 combo on mine. Only using primary diffusers....seems to work just fine.

***ZGN*** · 10-17-2008, 01:20 PM

I have heard under higher fuel pressure they could break off, and that would be bad.

10-15-2008, 09:50 AM	#1
88turboii destroy, rebuild, repeat Join Date: Feb 2008 Location: Charleston, SC Posts: 395 Rep Power: 18	tech tip: do not remove injector diffusers on my new rebuild, i removed the injector diffusers, thinking with they were affecting the fuel flow from my bigger injectors. apparently they are very important, because it ran like crap, hesitations at cruise, AFRs all over the place, etc. i pulled the injectors and replaced the diffusers and now she runs perfect. very smooth idle, no hesitations at all. apparently they help the fuel distribution in the air, stopping it from just hitting the opposite wall on the intake just a heads up, incase anybody was considering removing them

10-15-2008, 10:29 AM	#3
Whizbang Respecognize! Join Date: Jul 2008 Location: Δx = ħ/2Δp Posts: 3,190 Rep Power: 21	what i wonder is if they are still available from Mazda new __________________ For current updates and event coverage check out Follow on Twitter! @WhizbangRally Whizbang Rally's Webpage \| Facebook

10-15-2008, 10:53 AM	#7
Whizbang Respecognize! Join Date: Jul 2008 Location: Δx = ħ/2Δp Posts: 3,190 Rep Power: 21	for me they always seem a bit....fragile....from 20+ years of heat cycling. Would be stellar is a nice aluminum reproduction. __________________ For current updates and event coverage check out Follow on Twitter! @WhizbangRally Whizbang Rally's Webpage \| Facebook

10-17-2008, 10:47 AM	#12
Whizbang Respecognize! Join Date: Jul 2008 Location: Δx = ħ/2Δp Posts: 3,190 Rep Power: 21	1600s are big injectors though. Not sure how effective the diffusers are at about 3 times the fuel volume __________________ For current updates and event coverage check out Follow on Twitter! @WhizbangRally Whizbang Rally's Webpage \| Facebook

10-15-2008, 10:00 AM	#2
SpooledupRacing Guest Posts: n/a	Good info.. I knew that if I had removed them it would cause a problem with fuel atomization.. but I never wanted to test the theroy

10-15-2008, 10:30 AM	#4
SpooledupRacing Guest Posts: n/a	yes they are.

10-15-2008, 10:35 AM	#5
RotaryXperiment Rotary Fanatic Join Date: Mar 2008 Location: Bradenton, Fl Posts: 136 Rep Power: 18	i made sure to put mine in and replace with new orings per my engine builders suggestion.

10-15-2008, 10:51 AM	#6
SpooledupRacing Guest Posts: n/a	every time I get into an engien if they wiggle loose I pull them out inspect them for cracks, replace if nessecary and always put in mew o-rings.

10-15-2008, 09:01 PM	#9
*ZGN* Administrator Join Date: Jan 2008 Location: Birmingham, AL Posts: 2,264 Rep Power: 10	I pulled my secondary injectors ones when I installed my 1600. runs perfect!

10-16-2008, 11:14 AM	#10
classicauto crash auto?fix auto Join Date: Feb 2008 Posts: 816 Rep Power: 18	Yeah I have none on my secondaries, primaries ABSOLUTELY.

10-17-2008, 01:20 PM	#14
*ZGN* Administrator Join Date: Jan 2008 Location: Birmingham, AL Posts: 2,264 Rep Power: 10	I have heard under higher fuel pressure they could break off, and that would be bad.