Blown06

iTrader: (32)

I have no idea where to put this thread so I put it here. Mods, please move if needed.

I've been doing some searching and have found very little on the subject of deleting the IAC. I'm asking this because it seems like a lot of idle tuning issues for cars with big cams seem to revolve around the IAC circuit.

Don't some aftermarket TB's come without provisions for an IAC or am I missing something here?

Couldn't you just tune with the software and the idle screw or am I just way off base?

The reason why I'm asking is that I'm considering moving to a cable tb on my truck and want to make the switch as simple and clean as possible.

poconojoe

iTrader: (43)

If it isn't DBW you need the IAC
Anybody who can't get it to idle correctly with a big can, either need a better tuner or better tuning software.
You're not going to convert you DBW setup over to DBC very easily, depending on wht PCM you're running, its new enought that it doesn't even have IAC drivers in it

Blown06

iTrader: (32)

Anyone else have anything to add.

I've heard of guys running the aftermarket ford tb's with no IAC, I was just wondering how well it works.

69LT1Bird

iTrader: (1)

What he said.

Blown06

iTrader: (32)

Geee.......thanks

69LT1Bird

iTrader: (1)

Well what more do you need to know, I know guys with high 240/250 duration cams that idle at 900 with 50-80 IAC counts. It is doable if the tuner knows what they are doing.

Blown06

iTrader: (32)

Yea, but thats not the question I asked. I know the IAC can be tuned, I know some pcm's don't have the appropriate driver.

I was asking if the vehicle can be tuned without one.

gofastwclass

iTrader: (2)

I'm not a pro tuner but I can't see how logically you could tune a DBC car without the IAC unless you were willing to manually hold the throttle all the time. Drive by Wire cars get away with it because the throttle blades are controlled by the VCM.

Even carbed race cars have an idle control circuit of some sort.

I hear what you are saying but I don't see your logic with the statement "simple and clean as possible." You will still have the cable actuated TB.

poconojoe

iTrader: (43)

Sure it can be tuned without one, as long as idle speed isn't important to you and you don't care if it stalls at red lights. You can drive your vehicle without air in the tires also, but that doesn't make it a good idea.

10sec_rx7

it works and works fine, ive done it plenty of times on cars that have after market throttle bodies..

you have to set the base idle by using a hole in the blade then the ignition timing takes care of the rest.. cold starts and air con are not a problem

5.7 ute

Yep. The spark will have to be a lot more refined but it should still be doable.

poconojoe

iTrader: (43)

He doesn't have a race car here, at least not listed. You're not going to have a good idle, when its cold, or you'll have a very high idle when its hot.

69LT1Bird

iTrader: (1)

If you have to go through all of that to make it run without an IAC on the vehicle he has listed you may as well just keep the IAC and just tune it correctly.

10sec_rx7

no that is incorrect..

cold starts are still perfect and hot idle is still perfect..

you do understand that a change of 10deg timing at idle is generally all it takes to get a car with out a IAC to idle perfectly when cold and hot??

CalEditor

iTrader: (1)

Depending on the operating system you could be asking for a lot of trouble. You would have to disable a lot of funtcions in the calibration. A lot more than just IAC.

Blown06

iTrader: (32)

wow, lots of mixed opinions here.

I was looking around on yellow bullet at a thread that was titled something like post your turbo engine bay pics or whatever and noticed a lot of efi cars didn't seem to have an IAC. Actually most didn't seem to have one. Not sure what management system they are all using but it doesn't seem like that big of deal not to have one.

poconojoe

iTrader: (43)

Then why aren't you on Yellow Bullet asking all those guys about it, instead of disagreeing with the posters with experience and knowledge in this mater, that don't think its a good idea, which it isn't by the way.

All I have to say about 10Sec Rx7's posts is, do you live in an area that has as small temp swings as he does in Austria? A 10 degree change in timing isn't going to stabilize your idle speed with outside temps like mine that vary from below zero in the winter and get upwards to 100 in the summer, with a cam radical enough to give an IAC fits, trying to stabilize the idle.
Since you have HP Tuners, just ask Bill, I'm sure they have a great tune in the repository, that will work great for you.

69LT1Bird

iTrader: (1)

Are you sure you are not talking about the MAF? The IAC only comes into play off boost at idle, throttle blade closed.

Blown06

iTrader: (32)

Dude, chill the **** out. I was asking a question and have not once disagreed with anybody, I was just stating that there are a lot of mixed opinions on the subject. Sorry to awake you Mr. super god of tuning masters.

FYI: http://www.yellowbullet.com/forum/sh...d.php?t=251592

Yea, I'm talking about the IAC

edcmat-l1

iTrader: (10)

Hey Joe, lighten up. On the OP and Bill too.