HarleyZ28

iTrader: (2)

Modds in sig cam is the Hotcam

Car is M6, idles right at 1k rpms.

I want the idle to sound a little more aggressive

How low can I set the idle to safely so I can get the more aggressive sounding idle?

93z383

iTrader: (-1)

With a built motor there isn't really any defined number anyone can give you like what the stock M6 idle should be (800). 1000 rpm is right in the ballpark for your build, that's only 200 higher than stock and a pretty small increase given your build and M6, my 383 A4 idles @ 1000 and stock A4's usually idle much lower at around 500 IIRC.

Basically if you want to take the idle down more you just have to go back and forth lowering it and starting the car until it will die or idle poorly and you know you've reached your bottom and have to bring it back up. If you have an aftermarket throttle body you should (if you haven't already) drill the IAC hole through to the stock size, which gives you the best air distribution and idle quality. Cracking the blades open or drilling the blades feeds only the front cylinders and gives you a crap idle. All you need to do once that is done is go back and forth with the set screw and adjust your TPS to be at the proper voltage.

Since your cam isn't huge, the stock hole dimension should be enough when drilling the IAC but if it isn't you may need to take it bigger. Go to Golen Engine's website for the TPS slotting and voltage adjustment procedure, IIRC the voltage for a 97 is .55v . Every time you lower the idle make sure you get the TPS at .55v, start the car, and see how it idles.

HarleyZ28

iTrader: (2)

Can you say that in English for me now? LoL

93z383

iTrader: (-1)

lol and you have a built camaro? just kidding lol..

Well we need to know if your throttle body is stock or aftermarket first.

If it's stock, it's already drilled from the factory. Your throttle body has the IAC sensor on the bottom, and there is a passage that brings incoming air down into the IAC to be metered for your idle. Now there is also a small hole drilled straight through the throttle body so that some of that air goes directly into the intake. On aftermarket throttle bodies this hole is 90% of the time not drilled, and it needs to be.

Your TPS (throttle position sensor) on the left side. This tells your computer when your throttle body is open/closed, and at what %. 100% = wide open throttle, foot to the floor. When you need to tinker with your throttle body to adjust your idle, you can't just adjust the set screw and leave it, because your TPS reading will then be off. For example if you upped your idle a bit using the screw, the blades would be slightly open letting air in, and your TPS would be reading that you actually have your foot on the gas a little bit. But if you adjusted your TPS back down to the proper voltage, you would be letting in the extra air your engine needed to idle, and the computer would read that your throttle body was not actually open, allowing all the other readings to be correct.

I'm on the verge of falling asleep while writing this so forgive me if it's hard to understand or I made a mistake lol... I'm about to face plant on my keyboard.

HarleyZ28

iTrader: (2)

Thank you this makes more since.

My Throttle body is stock btw.

93z383

iTrader: (-1)

Honestly you should leave it alone, 1000 is fine for what you got going on.. there has to be some idle increase to feed the cam the extra air it needs. If you really want to try to lower it do like I said.

But if your TB is stock and hasn't ever been messed with, the blades are already closed as far as they can go and there isn't really any way to lower the idle any more other than by tuning.

HarleyZ28

iTrader: (2)

If I have it tuned to idle lower, would I have to mess with anything on the TB? Then again from the way your talking, could a tuner even lower it much more than were it already is to make my idle a bit more aggressive?

Surely there has to be something here I can do, I have heard car that sound like there barely running before with between the cam and idle speed.

nitrous2fast

iTrader: (2)

Really you can have it idle at pretty much what ever you want it to.... It really depends on the tune. Timing and AFR have a huge impact on how well an engine idles at a certain RPM. Just get someone who knows what they are doing to adjust your tune correctly and you shouldnt have a problem. my .02

BTLD_LS1

iTrader: (1)

Seems like an awful big injector for your setup, might cause it to load up some if u go lower on idle

HarleyZ28

iTrader: (2)

Yeah it is a big injector for my set up, but it does leave room for improvement later down the road.

spudnick3119

Its all in the tune... datalogging the car would tell you where you could set it to. I have mine set at 750 and it idles great. Stock TB.

BTLD_LS1

iTrader: (1)

Sure but I think ull have trouble getting a small enough open time on the injector at a lower idle, just my thoughts....

93z383

iTrader: (-1)

All this is true which you have to take into account.. you may want a more aggressive idle, but don't fix it if it ain't broke

Your best option is to consult with your tuner and have them lower it, they will be able to tell you if the injectors and everything else is running properly with the lower idle.

Or get a beastier cam. You can have my CC306, that thing CHOPS in my 383 lol... car's been a lot of fun but with all the technology that's come out just about any off the shelf cam will **** on it, let alone a custom grind. I could be making way more power with a custom grind