Dirtyturbo

So as i was upping the boost tonight it was doing good untill i did a few longer pulls where it went above 10psi and it went lean on me. I immediatly backed it down to 9psi and its fine at that level. However i want more.

Can you run bigger injectors on a stock ecu while reataining a decent idle and driveability while out of boost?

I know i know.... get an ecu... thats what your gona say.. but i am kinda unemployed at the moment so i dont have money coming in to afford one right now... And in the end im gona need bigger injectors once i do get an ecu anyhow so i was just curious if its been done?

olderguy

iTrader: (1)

The ECU will handle larger injectors. I have run 305"s with no problem idling. What are you doing to add fuel in boost? AFPR?

RedTurboMiata

heres a page with a lot of info about turbo miatas. including fueling.
http://miataturbo.wikidot.com/

Pic snagged from your build thread, you have a vortech fmu. more than likely with the 6:1 disk installed. you could change the disks out, along with upping the injector size.

Dirtyturbo

Well its supposed to be a 12:1 disc in there.. i dont know what the disc inside is sposed to look like though. There was some good info in there.. That page says you can run up to 305cc and still get it to idle. Any idea how to tell what disc is in the fpr?

olderguy

iTrader: (1)

Open the top of the AFPR and look. Stock disc is 12:1 and covers most of the area. If you are running stock FP and stock injectors you will not do much better than 7psi without lean spots. 1.8 injectors and a good stock FP will only give you a safe 8psi.

Dirtyturbo

Ya im bout ready to just turn it down to 6 or 7 psi and advance the timing... im bout to give up on life with no job now to afford an ecu and injectors and all that jazz. Car is a pos anyways.. im just gona drive it and build another one thats worth putting the $$ into.

adamturbo

if you are running rich at idle and want to run leaner at idle with bigger injectors its easy. before you do this be sure you have a wide band AF guage installed and working proper. i was running super rich at idle with 330cc injectors 10.5 on my AF readings i got it to 13.8 wich is alot better. simply drill out the small round plug on your afm. its neer where your silicone coupler is on the engine side of the afm . drilling the plug out gives you access to an adjusting screw. with the car running and at temperature back the screw out till your AF readings are in the high 13,s . then go for a burn and make sure your AF readings are still rich under WOT. be very carefull doing this as you dont want to cook the motor. its best to do small adjustments at a time.

sixshooter

Does that adjust only the base fuel pressure at vacuum or does it effect the entire range?

adamturbo

for me it just altered the idle AF,s. that is why you should adjust it a little at a time and test drive to be sure your still rich at wot