Oversized injectors OK?
#21
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well my a/f is whatever i set it at. it made to most power on a mustang dyno running an 11.8. got a track rental coming up will see what it actually runs the quickest at. fuel pressure is at 44 at idle. never checked it at WOT since my gauge is under the hood. i can't recall my duty cycle id have check an old log. im thinking its in the 70s though.
#22
If you're happy with what you have thats great, I don't think you should spend any cash at all on changing it. However, just because you can get away with it doesn't make it best.
#23
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If you are in the 70's (WOT/peak) you will probably be giving up quite a bit of low end. Also, 11.8 seems way too rich. For maximum N/A power you should be much closer to 12.9 at WOT in high gear. I'm not sure about the stock computer, but with DFI, etc. I have found that I have to compromise a little on A/F (richer) on the low end, because of the rate of acceleration that the motor sees in first gear vs high gear.
#24
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I did not say it wouldn't idle or drive plenty fine. **** carbed engines are running all over the road anywhere between 12 and 16:1 a/f ratio and nobody knows the difference with them either until somebody tunes it up for them. What I said was the adjustment is not as fine and fuel control can be improved by running the right injectors ie it will run smoother. I mean not that I know anything about it, people confuse my 24x/24x cammed 355 with a cc503 at idle all the time with no bucking or surging at low rpm cruise. Let me ask you this, have you ever tried anything else besides your current injectors? If you haven't then how do you know? I just happen to be a bit opinionated about this since one of my good friends owns an injector shop. You would be shocked at the things you can learn just by watching different brands and different pressures on the test bench.
If you're happy with what you have thats great, I don't think you should spend any cash at all on changing it. However, just because you can get away with it doesn't make it best.
If you're happy with what you have thats great, I don't think you should spend any cash at all on changing it. However, just because you can get away with it doesn't make it best.
#26
I wasn't challenging you or anything, just simply asking for my sake. Can't hurt to learn something new. To answer your question, yes I have tried other injectors (sizes and brands). From stock 24# to ford 28s, accel 24s, holley 36s and now the ford 42's - so far the best has to be between the stockers or the 42's. Stockers when the car wasn't tuned and now that the car is tuned for the 42's, it runs exceptionally good. I still want a smaller injectors though.
#28
The reason why I had started this thread is because I saw a set of 42 lb injectors for 160 dollars. I knew that they were way overkill, but it would be nice to not have to swap injectors every big mod I do. Right now I am putting the car back together with a cc503 cam, but next year (the day after I smog the car in april), I will be going with a bigger custom cam. Even then 42lber's sound too big.
So i'll keep looking for the right injectors then. Thanks for the help.
So i'll keep looking for the right injectors then. Thanks for the help.
#33
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Well Like I said I run 85lb NA, only because I removed the supercharger and installing a Turbo and didnt want to purchase another set just for a short time. By dialing in my MAF, IFR and PE mine idled perfect, no bucking or surging at low speeds and smooth through out the rpm band. Of course this was not optimal but this was just for a short term use..I agree with Giz where a 40% duty cyle @ Wot is not the very best approach, the injectors will be too lazy..