I just spent a shitload of cash on my car, 2 trips to the dyno, and the tuner still can't get the idle right, along with some other problems I've been having that he couldn't reproduce on the Dynojet. He said that larger injectors will pop at idle, and that the RC 750 injectors are actually just reworked 440 injectors that don't actually flow at their 750cc rating. I selected these injectors because I don't want to deal with a resistor box, especially when I have to swap injectors before emissions testing.

The car runs very smooth when driving around normally, and also in boost. The most annoying thing occurs when I shift gears, unless it's done quickly. It sputters, hesitates, then accelerates. The same thing happens when I attempt to match the revs to downshift, then punch it. The highway I take on the way home has a lot of mountains/hills, and when going downhill it sputters and pops like crazy, especially in certain areas of vacuum. Cruise control made things worse, and very jerky. When on the gas, the car is fine.

Is the popping idle normal for larger injectors? Are the other issues I'm having something that only a street tune or load bearing dyno can solve, or does this have something to do with the injectors?

Thanks for the help! I miss my Greddy and 440 injectors. Oh well!

 

I have RC saturated 650cc injectors w/ hondata and my car idles perfectly fine. It doesn't pop at idle and never hesitates. Runs perfect. If you have the flow sheet for your injectors you'll know exactly what they flow. Mine were all slightly above 650cc/min.

What EMS are you running?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dustin &raquo;</TD></TR><TR><TD CLASS="quote">I have RC saturated 650cc injectors w/ hondata and my car idles perfectly fine. It doesn't pop at idle and never hesitates. Runs perfect.

What EMS are you running?</TD></TR></TABLE>

I run fine with 750's/Hondata S200

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dustin &raquo;</TD></TR><TR><TD CLASS="quote">I have RC saturated 650cc injectors w/ hondata and my car idles perfectly fine. It doesn't pop at idle and never hesitates. Runs perfect. If you have the flow sheet for your injectors you'll know exactly what they flow. Mine were all slightly above 650cc/min.

What EMS are you running?</TD></TR></TABLE>

Hondata S200. I remember reading that you keep a laptop in your car so you can make adjustments. Wouldn't that have something to do with the quality of your tune vs. mine?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RyanCivic2000 &raquo;</TD></TR><TR><TD CLASS="quote">

I run fine with 750's/Hondata S200</TD></TR></TABLE>

What kind of tuning was done, and what kind of dyno?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B16A Grenade &raquo;</TD></TR><TR><TD CLASS="quote">

Hondata S200. I remember reading that you keep a laptop in your car so you can make adjustments. Wouldn't that have something to do with the quality of your tune vs. mine?
</TD></TR></TABLE>


It very well may. I haven't really had to change the low maps much at all... just slight fueling changes. The timing maps are stock on the low cam.

Is this on a B16? It just sounds to me like the car isn't tuned correctly.

 

BTW, I bought these injectors brand new, and they all flowed (according to RC), higher than 750cc. The tuner's claim was that he personally flow tested the 750cc injectors before, and they were less than 700cc.

 

I think your tuner is full of el poo.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dustin &raquo;</TD></TR><TR><TD CLASS="quote">
Is this on a B16? It just sounds to me like the car isn't tuned correctly. </TD></TR></TABLE>

LOL, I guess I have to change my name to something else. I don't have the B16 anymore, just the head. It's a little bit of everything.

I don't think it was tuned properly, either. Since it's a brand new build, and I don't live there, the engine was broken in on the dyno.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dustin &raquo;</TD></TR><TR><TD CLASS="quote">I think your tuner is full of el poo.</TD></TR></TABLE>

No, he just thinks his **** doesn't stink.

 

you could have a bad injector. it happens quite often and would explain all your symptoms.

 

I have Rc750cc, and they flowed 810cc

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Muckman &raquo;</TD></TR><TR><TD CLASS="quote">you could have a bad injector. it happens quite often and would explain all your symptoms.</TD></TR></TABLE>

Man, I hope not. Like I said, it's smooth most of the time. These problems occur in vacuum. My intention is to take the car to a dedicated tuner. I have someone in mind.

 

Did he even "tune" part throttle at all? if not that's why it's running like poo. Most "tuners" just tune WOT/boost.

 

I have no clue. He's up on his pedestal, where I can't even see what's on the computer screen. Customers aren't allowed up there "for insurance reasons." You're probably right, though.

 

Mine popped at idle with 750's and hondata, we just added more fuel at idle and it cleared it up. What your hearing is a lean pop.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nsxmatt &raquo;</TD></TR><TR><TD CLASS="quote">Mine popped at idle with 750's and hondata, we just added more fuel at idle and it cleared it up. What your hearing is a lean pop.</TD></TR></TABLE>

i second that... i used to watch my wideband bounce mid 15 to 16:1 at idle and it would pop.... also when decelerating and a/f starts dropping into the 16 and 17 a/f it pops, farts and rumbles. every car is a little different but it sounds like lean pop.

 

whats your a/f at idle?

sounds like your a little to lean at idle if it pops.....

also whats your air/fuel while cruising around? having it lean for fuel mileage is good but TOO lean will cause tons of weird drivablility issues.

 

Running the RC 750's (saturated) on Uberdata and I have no idling issues. It pops (lean pop) only at the beginning of a decelleration. Problem would be obvious to me

Phil

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nsxmatt &raquo;</TD></TR><TR><TD CLASS="quote">Mine popped at idle with 750's and hondata, we just added more fuel at idle and it cleared it up. What your hearing is a lean pop.</TD></TR></TABLE>

He did say something about richening it up to try and help the problem. I started to drive home, and in traffic, the idle surged up and down, similar to when my IACV was bad. I turned around, and went back. He fixed the surging, but the pop is still there. I prefer the pop to the surging any day!

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by non-VTEC &raquo;</TD></TR><TR><TD CLASS="quote">whats your a/f at idle?</TD></TR></TABLE>

I don't have a wideband. I bought an EGT, but haven't hooked it up yet.

Thanks, everyone. It sounds like I have a lean condition in vacuum. I'll live with it for a while.

I know you guys don't think much of cars that are "just" in the 300+ whp range, but right now it's less than 60 degrees outside, and even at low boost (about 300whp), it feels really strong going uphill. It's plenty for the street.

 

You need street tuning :-)

 

mine makes that poping noise at idle but i dont think its a lean pop, my a/f's at idle stay lower than 15.5(meaning richer) but i have 525cc precision injectors with uberdata.

 

I have RC 750cc with AEM tuned by Mase and I don't have any issues of popping at idle.