Injector help!!!!

Postby **Boyracer** » Tue Jan 02, 2007 8:33 am

Ring this place...I rang and ordered 450cc injectors for my SE(which I think are the RX7 ones)...had them in the mail the next day...

http://www.powerflowinjection.com/Default.asp?c=23229

Fatty · Postby **Fatty** » Tue Jan 02, 2007 7:51 pm

have a look at this thread for a bunch of options for plug and play injectors

http://www.miataturbo.net/forums/showthread.php?t=4288

i got mine on ebay

Boags · Postby **Boags** » Tue Jan 02, 2007 9:01 pm

305cc green top supra injectors were $100 from a wrecker for all 6(supra is a straight 6). That thread Fatty posted is the bible.

I'll sell you 2 if you want! :lol:

4sfed5 · Postby **4sfed5** » Thu Jan 04, 2007 6:12 pm

be careful of some rx7 injectors as some are from the \"hotside\" of the engine (secondary injectors) and often fail due to the increased heat...

neil d · Postby **neil d** » Thu Jan 04, 2007 6:56 pm

Boags'MX5 wrote:305cc green top supra injectors were $100 from a wrecker for all 6(supra is a straight 6). That thread Fatty posted is the bible.

I'll sell you 2 if you want!

Which wreckers Boags as I also need a set?

Neil

Boags · Postby **Boags** » Thu Jan 04, 2007 7:00 pm

AllJap at sangate rd virginia! Not a very helpful bunch on the phone, but the ocker ozzie out the back bent over backwards for me!

You just have to know what you are looking for - Light green top 7mge injecotrs.

Boags

neil d · Postby **neil d** » Thu Jan 04, 2007 10:28 pm

Boags'MX5 wrote:AllJap at sangate rd virginia! Not a very helpful bunch on the phone, but the ocker ozzie out the back bent over backwards for me! You just have to know what you are looking for - Light green top 7mge injecotrs.

Boags

Thanks Champ

I will head down tomorrow.

Neil

Fatty · Postby **Fatty** » Sun Jan 07, 2007 11:01 pm

hey ant, seeing as how yr questions have been answered i hope you don't mind if i hijack yr thread

i got a pm recently from someone with a few questions about how my stock ecu was handling my 460cc injectors. he thought that i would be having some fuel flooding issues.

thought i'd share my real world experience with everyone after living with this setup for a while.

some people will tell you that you can't fit such big injectors on the stock ecu. i think there are 2 types of people who will tell you this. the first type are people who have tried and failed , probably because they have been using an inferior piggyback, i guess. i am running a jaycar digital fuel adjuster.

the second type are people who have read it on an interent forum, so just repeat what they have read as if it is the gospel.

people will say that fuel consumption will be horrendous and that it'll run like a pig, but i went for 2 long runs with boags when he was in town last week. we filled up at the same time. on the first day when we refilled after 220km of very hard driving, my car only needed about 0.8L more petrol than his. the next day after 300 more km, it was about the same, 1 litre or less, can't remember exactly. can't say i noticed much of a difference in drivability or performance between our cars either. if anything mine might have been a bit zippier and more responsive, but there may have been other factors involved ( a passenger in boag's car)

i am naturally asprirated at the moment, but obviously the reason i have them in there is coz i am putting together a turbo system.

the only issue i have had is that there is a bit of an idle dip, which has cause my car to stall about 3 times when pulling up to a full stop at traffic lights after a hard run on the throttle (not bad for about 2 months of driving with the 460's). i'm sure this could be easilly cured by fiddling with the base idle screw or whatever, but since it is such a minor problem i haven't bothered with it.

Sean · Postby **Sean** » Sun Jan 07, 2007 11:08 pm

Fatty,

I've been one who has said it's npot possible to run 460ccs on stock ECU, HOWEVER I do not consider it a stock ECU if you are altering it with a piggyback - Just to clarify

Fatty · Postby **Fatty** » Sun Jan 07, 2007 11:13 pm

understand that sean, but others have said it is impossible even with a piggyback.

Boags · Postby **Boags** » Mon Jan 08, 2007 11:42 am

Fatty wrote:understand that sean, but others have said it is impossible even with a piggyback.

Something to do with it being outside the maximum perameters of the AFM -> ECU volotage signal.

Yep, on open loop Fatty is actually running LEANER than me on my stockies, hence more power. Fuel consumption with that little difference can be put down to driving style too, I keep it in third and drive through from 4ishKrpm, whereas fatty drops to second... (for eg.)

I think it is good evidence to support the fact that you should not repeat what you read on forums anyway! :lol:

Boags

4sfed5 · Postby **4sfed5** » Mon Jan 08, 2007 2:36 pm

you cant get 440cc+ to idle even with a piggy back and heres why.......
The LEANEST AFM voltage that the ecu will accept is around 3.85 volts at idle and when you dial up 330cc injectors on an emanage the correction voltage is 3.85 volts.......so any bigger injector than that wont run correctlly as the ecu just cant make any more of a correction......Some guys have said they can get it to run fine with 440's but when pushed admit that the gas mileage sucks and they cant start the car half the time and it idles funny...to me thats not running \"fine\" :mrgreen:

any limitation in injector size IS NOT governed by which type of piggy back is used..it is governed by the fact that the factory ecu cant lean out any more than 330'cc due to its fuel mapping and afm voltage acceptance.
fitting 440's to a car and going on a cruise wont prove anything either as the car runs in closed loop off the O2 sensor and will simply cut the injector signal down to keep it at stoich anyway.....the proof in the pudding is starting, idling and open loop fuelling...not while cruisiing.

All of the above has been PROVEN by me by logging the duty cycles and o2 sensor voltages via the emanage and feeding the ecu a dummy signal via a trimpot to imitate the afm..after 3.9 volts absolutly no more leaning was made by the stock ecu...i treid some 440's too and the results were the same..it would idle (just) but you should have seen the 02 sensor logs.....the car was DROWNING in fuel and even in closed loop idle it was barely able to keep going.

If you want to lean it out any more then you will have to change the ECU's \"clocking crystal\" from the stock 4Mhz to 4.4Mhz for a 10% leaner mixture or 4.8Mhz for 20% leaner mixture....this will also advance your timing by up to 4 degrees per .4 step and effectively remove the rev limiter.

Fatty · Postby **Fatty** » Mon Jan 08, 2007 2:43 pm

4sfed5 wrote:you cant get 440cc+ to idle even with a piggy back and heres why.......

i give up.

so you have tried this for yourself?

edit*

ok, i see you've edited your previous post and provided more detail.

Fatty · Postby **Fatty** » Mon Jan 08, 2007 3:07 pm

4sfed5 wrote:fitting 440's to a car and going on a cruise wont prove anything either as the car runs in closed loop off the O2 sensor and will simply cut the injector signal down to keep it at stoich anyway.....the proof in the pudding is starting, idling and open loop fuelling...not while cruisiing.

again, i'll say that i didn't just fit them and go for a cruise. they have been on the car for a while now. as you say the proof is in the starting, idling and open loop fuelling. my car has started first time, every time, for 2 months now. every single time. my car idles perfectly, even in open loop. i have an air fuel meter fitted to my car so trust me i know the difference and i can easilly tell when the car is in closed or open loop. i can start my car and head off immediately (before the o2 sensor has warmed up) and the car runs perfectly in open loop. also when dríven hard and the engine is under load in open loop, it runs perfectly.

4sfed5 wrote:All of the above has been PROVEN by me by logging the duty cycles and o2 sensor voltages via the emanage and feeding the ecu a dummy signal via a trimpot to imitate the afm..after 3.9 volts absolutly no more leaning was made by the stock ecu...i treid some 440's too and the results were the same..it would idle (just) but you should have seen the 02 sensor logs.....the car was DROWNING in fuel and even in closed loop idle it was barely able to keep going.

the only thing you have PROVEN is that a) the emanage is inferior, or b) your ecu's in new zealand are different from our australian ones.

4sfed5 · Postby **4sfed5** » Wed Jan 10, 2007 5:00 pm

HAHA yeah right...the emanage is not inferior......for my experiement i used the emanage to data log the stock duty cycles and afr's not for correction initially........

LIKE I SAID...............IT IS THE STOCK FACTORY ECU THAT CANNOT ACCEPT A VOLTAGE OF MORE THAN 3.9 VOLTS THATS LIMITS THE AMOUNT OF CORRECTION THAT IS AVAILABLE................

IT DOES NOT MATTER WHERE THAT CORRECTION COMES FROM......EMANAGE, DFA , SUPER AFC ETC THEY ALL DO THE SAME CORRECTION...(Its about the ONLY thing they do the same infact).

what is your ecu seeing as a corrected afm voltage at idle with the dfa then??????id like to know.