Injector duty cyles -> Would like input
#1
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At 10.5 psi @11:1afr I'm seing 89% duty cycles which is getting a bit high. I suppose my stock fuel pump could also just be getting tired, but it seems like I should have more headroom than that using 450cc injectors...Any thoughts on whether or not inline resistors effect IDC %s?
What kind of duty cycles are other people seeing at similar boost levels?
Edit: after doing a quick search, I'm going to just assume that my fuel pump is eating **** and change it out for my 190 + re-wire it. I guess I was just being overly hopeful in my expectations for the sad old stocker.
What kind of duty cycles are other people seeing at similar boost levels?
Edit: after doing a quick search, I'm going to just assume that my fuel pump is eating **** and change it out for my 190 + re-wire it. I guess I was just being overly hopeful in my expectations for the sad old stocker.
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Thanks for the input. I'm heading to a dyno day on the 10th and I'd really like to turn this ****** up a little more and hit 250. I guess its going to be a late friday/early saturday for me next week :/
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Here's a 3rd gear pull from my car:
![](http://img37.imagefra.me/img/img37/2/3/30/thraddax/f_4ftq8e5m_4be1fff.gif)
That's with a Walbro 190 and 465cc injectors. AFR was in the low 12s for most of it, and then dipped into the mid 11s there at the end. (Not sure what's up with that...)
As you can see, that's 198 kPa, which is 14.something PSI of boost. IAT peaked at 100°F, from 69°F ambient.
![](http://img37.imagefra.me/img/img37/2/3/30/thraddax/f_4ftq8e5m_4be1fff.gif)
That's with a Walbro 190 and 465cc injectors. AFR was in the low 12s for most of it, and then dipped into the mid 11s there at the end. (Not sure what's up with that...)
As you can see, that's 198 kPa, which is 14.something PSI of boost. IAT peaked at 100°F, from 69°F ambient.
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