viza

Don't you need to re-tune if you change your setup?
I'd do some research before I turned the ignition on again... I'd betcha some c-notes that you are running way too lean.
-Viz

chp2150

emBOSSed,
I'll see if I can help you out.

The basic area of a circle fromula is A = radius squared x pi (3.14). So knowing this, Area =(27.5 x 27.5) x 3.14. This equals 2374.6 square mm. Double that for both throttle holes and you have 4749.25 sq mm. Now working backwards for a single hole. Take 4749.25 and divide by 3.14, you get 1512.5. Now take the square root of that and you get 38.89 for the radius, x2 for the diameter and you end up with an equivalent hole size of 77.78 mm diameter.

If you remove the throttle body and measure the intake holes for the plastic intake, it's 62mm. That works out to about 88 mm equivalent diameter for a single hole. The Granatelli CAI is 90 mm and so are some of the others. Why Ford is using a smaller TB size is puzzling. If you calculate the size of the dual exhaust, it comes up to about the same as the 88mm diameter. So, if you use an aftermarket intake, a 62 mm throttle body and 2 1/2 inch (stock) exhaust, it is a constant diameter air flow system. Obviously, my electronics knowledge is not applicable to air flow physics![sm=wakeup.gif]

The difference between the 55 mm diameter TB and the aftermarket TB of 62 mm is about 11% increase in diameter. javascript:void(opener.AddText('[sm/=wakeup.gif]'));self.focus();self.location.href='smiley.asp'

emBOSSed

Thanks CHP2150. That makes sense of it. Do you think the Granatelli one is the way to go? I know some brands have been failing.

My05GT

Well...I finally attempted the install of my GMS TB today. I've had it sitting in the garage for some time now. Just never got around to it. The install seemed to go fine, no real issues - I did snap a couple of the screws when removing the gear cover. So I reassembled the new TB got eveything buttoned up, started it up - failsafe mode. ****! I figured it was the spring inside there. Took it all apart, reset it - FailSafe Mode. Damn!. Long story short, I can't get it adjusted right. Everytime I think I have it, I get FAILSAFE MODE! I'm a bit disgusted. What should have been about an hour job, took 4hrs and I didn't even get it working! I just decided to pack it up for the night.

So...any suggestions? I could disassemble it again and try setting the tension. I tried to follow the notes posted here on TB replacement. They were well done. Question: What position does the gear have to be in when putting it back together? Up close to that stop screw? or down in the other direction?

I lined up the tangs with the appropriate holes, put the gear cover on, took that little lid off, turned the spring tensioner 3/4 counter-clockwise. The tangs obviously didn't match up, but it did hold there. Still....got the failsafe mode. I'm ready to rip it all off (CAI too). But I'm afraid it I can't get the spring tension adjusted right on this one, I probably can't get it done on the stock TB

Any help? Anyone have a good exploded-view diagram of the TB? How about snapping a pic of the TB with the little lid off, so I can see where the tangs are in relation to everything when installed.

Dave

rex7010

My05GT

Your car ran fine before this right...??? so put your stock one back on and take one on the chin..

I am not slamming on you ( so please don't take that this the wrong way )

but if my car ran fine.. and I am only going to get just a few more HP out of something that is driving me nuts..

then I would throw the thing away .. or put it up on flebay... not every mod is a good mod.. and this one seems to fall into that....

JMO and only that.. but .. maybe somebody else can help you out..??? but to me.. it just doesn't seem like it is worth all the trouble for just a few more HP...

best of luck in whatever you decide on this..

R

chp2150

I had a GMS TB. Note the use of the past tense term! I installed it and had lots of problems. I've read many other posts on the GMS and BBK on this forum and other forums and it seems to be random luck if the thing is going to work. I sent mine back to GMS and they were great about the refund. Now the GMS intake system: I love it!! No tune required and it dyno'd and additional 20 HP and the A/F mixture was excellent at wide open throttle. You'll really notice a difference and I've had no problems at all with it.

My05GT

No offense taken...seems like good advice right now. I guess the next question is, am I going to have a problem putting that spring back on and getting the setting right? Also, does the TPS setting matter. If so, how can I get it back to where it should be?

Thanks

m_stavros

Where can i found infos about the electrical circuit of the throttle body?

Need help please

shaners90lxhatch

What do you want to know? There are four TP wires and two TACM (Throttle Actuator Control Motor) circuits. The TACM is a varaiable polarity/voltage. This motor is controlled by the PCM and will open or close the throttle based on a duty cycle from the PCM. The TP circuits are a VREF (5v signal), Signal return (PCM supplied ground for the TP) and two signal wires (TP A and TP B). Both TP signals are continuously monitored for correlation by the PCM. The TACM is continuously load tested by the PCM for resistance and continuity. The TACM has no feedback, however. The PCM only has the TP signals to let it know what position the throttle plate is in. I have all the factory wiring diagrams and repair manuals (along with some other resource materials) if you need further info. Bottom line, you are extremely likely to experience failsafe mode related faults if this system is manipulated in any way. This is because the system is very sensitive to signals that are not where they are supposed to be. This sensitivity is what keeps a power line or two way radio from making your car go WOT. The throttle position signals must have proper signals individually as well as relate to one another very closely. One signal starts with low voltage and climbs up. The other starts with high voltage and goes down. They must intersect in exactly the right spot or you will set P2106,2135. P2111,2112 mean that the TP signals do not indicate the proper throttle position or will not reach the intended position. Basically the computer anicipates what the voltage is supposed to be. If the actual voltage is different than this anticipated value - you end up with failsafe mode.

MusiccityGT

Wow, haven't seen this thread in a long time! I take back everthing I said earlier in this thread. Although things went good for awhile with my T/B change, it all went south a month or so into it. Back to the factory T/B and no problems. I doubt that I will ever consider doing one again.