BBK 65mm 04 Cobra and idle hangs at 1500

[seidler]

I installed a 65mm BBK throttle body on my 04 Cobra and it runs fine except the idle hands at 1500. If I blip t6he throttle it goes down to 1000 and then slowly drops to 750. I have set the TPS from .82 to .98 and adjusted the throttle stop as BBK recommends (listed below) and looser to no avail. Any Ideas?

BBK Idle Stop Adjustment
With Engine Off set stop to .010 cleatance between stop screw and linkage and then turn in 1 complete turn.

[Hazman]

seidler

Be very careful with the BBK on that 04. A good friend had an 03 and installed the BBK. Anytime we got into heavy traffic where he was idling for a while the BBK would start to bind open. We were in Gatlinburg one night and he could not get it below 4,500 RPM!!:eek: We had to pull off on a side street and let it cool for an hour. He finally sent it back and got a refund.

What we figured out was that since the 03 and 04 have a metal connection between the throttle body and the supercharger more heat was being transfered to the throttle body. The shaft for the valve and the throttle body are different types of metal and expand at a different rate causing the shaft to bind and the spring could not pull it closed.

On the open highway this is not usually a problem but anywhere you have high heat levels under the hood (city traffic, open tracking , etc) it can be a dangerous situation.

Hope you don't have this problem but just wanted to give you a heads up.

:thumbsup:

[Big T]

I have one of those also. My idle hangs at about 900 but the gas pedal has lost some of its touch. It seems to stick initially. Does anyone know a good inlet to get with that part? The stock one has that big tonsil that impedes the air flow and it also doesn't fit exactly with the TB.

[seidler]

I hand ported the intake with a dremel. It comes out nice if you take your time. I used the metal fluted cutters to remove the metal (quite alot, almost 3mm around the complete circumference) and the sandpaper flap wheels to do the polishing.

[Winston]

If you are satisfied that the TB or cable are not binding you may want to see if your Predator can be used to make changes to the idle and dashpot settings.

[seidler]

I replaced the TB with a new one (Summit swapped it out) and it is fine.

[todd55]

:) I'm new to the site. i have a 03 cobra covert that i just love
I have done a cat back system and replaced the crappy stock shifter. My question is this........Throttle body and cold air systems,
What should I look for for this great machine?

[OKC03Cobra]

Originally posted by todd55
:) I'm new to the site. i have a 03 cobra covert that i just love
I have done a cat back system and replaced the crappy stock shifter. My question is this........Throttle body and cold air systems,
What should I look for for this great machine?

I have the BBK TB and MAC CAI and am completely satisfied. You might also think about Bassani X-pipes. 2.93 pulley and Diablo chip, along with a good dyno-tune.

[todd55]

Thanks, should I be wary about the sticking throttle as
the guys above with the bbk?

[todd55]

also, I found a "accufab single blade TB on the web. is there any
avantage to that? It's twice the price and I'm confused!

[Big T]

Originally posted by todd55
Thanks, should I be wary about the sticking throttle as
the guys above with the bbk?




No. It just loses some of it's touch when slowly coming out of first. The throttle doesn't get stuck at a RPM per say . When I press on the pedal it has a slight resistance to it and then it releases. As a result, I wind up revving the engine a little too much and it looks like I cannot drive a stick shift. I'm getting used to it and It has loosened up some.

[Mirage]

Question for all~ I have a question regarding my 2003 Cobra. Since doing this mod I really never got my idle to set correctly. Most of the time it sits around 1,200 rpm but if I rev it to 3,000 rpm (at a light or while downshifting) then it falls to 750 rpm at idle. The funny part is that once the car is turned on it idles around 750 rpm (where it should be) but once taken for a drive it becomes somewhat erratic. For a few days everything seemed fine (perhaps the moon was aligned with Jupiter) but since then this gremlin has reared its ugly head.
I do notice that the linkage on the throttle body never really touches the set screw after WOT (Wide Open Throttle). If I push the linkage to the set screw then the rpm’s drop. Of course this isn’t practical because I can’t open the hood every stop light. Not that I would want to do that anyway. Although it would make for some fun viewing by other people in the next lane.

I also got a stiffer spring and drilled a 1/8” hole into the back plate to try and compensate for the higher rpm’s. This I thought would do the trick but in reality it just makes my pedal feel harder. So after two paragraphs of description, does anyone know how I could over come this problem? I’ve thought of unplugging the battery and letting the computer die and then re-attach the cables to see if a “re-learn” might do the trick but I haven’t tried that yet. Or, get a HyperTech handheld and see if I can set the idle but I don’t want to spend $350 on something that “might” help.

I’ve also attached some pictures (scaled to 640x480 but have larger at 1280x1024) to illustrate what I’m talking about. Although from everyone's comments I think people have a good sense of what I’m dealing with. If you have any suggestions for me I’d gladly be willing to try them. Thanks in advance!

Image 1 (BBK Throttle Body):
http://207.5.42.131/test/irdiscuss/images/bbk throttle body.jpg

Image 2 (BBk Throttle Body - Zoom):
http://207.5.42.131/test/irdiscuss/images/bbk throttle body - zoom.jpg

Image 3 (BBK Linkage):
http://207.5.42.131/test/irdiscuss/images/bbk throttle linkage.jpg

[seidler]

I am not sure about the return spring. The stock TB doesn't use one. I cannot tell much difference with it installed. The throttle seems stiff with or without it especially the initial off idle opening. I agree it does make it difficult to be smooth in traffic.