Guys......every once in a while I will see used throttlebodies on E-bay. What kind of trouble can I get in with those? They are $100 cheaper but not worth it if I am going to damage something. Also, do they need a tune modification or not? Some sites indicate yes, some no. I have a C&L intake with custom tune now.
Just avoid throttle bodies all together. Our stock ones flow extremely well and aren't really a restriction until around 450 horse or so. You're probably making about 330-340. I put a BBK 62mm on my old car (it was free) but took it off after about a week of driving. My car was much more responsive with the stock one and got better mpg.
Thanks. So what's the next bolt on with the biggest bang. I already have the air intake, ram air, under drive pulleys, and custom tune. I have not done anything to the exhaust except after the cats.
Ram air is a myth. What you have at best could be described as a "Ambient Air Duct". That hole in your hood you have would need to be at LEAST 12" higher off of the hood to get anywhere anything resembling "Ram". And then you need to be going at LEAST 120mph fo it to show .1psi. And to compound the problem even if that hole was high enough it's way too big to be able to crate any "ram" effect.
I have run around Daytona at 190mph with a far better intake system with that and a pres transducer. You would be amazed how elusive "ram" is.
Get a gear. That starts working at .1mph.
Next comes the question:
"What gear should I get"
Try this (posted at least 15 times now):
You have the ability to answer the question of what gear ratio will work best for you. Don't simply listen to some dork that says you "need X.XX gear because they ROCK!" For all you know they are borderline brain dead. Just because they don't mind driving around with the motor spinning to the moon doesn't mean you won't.
This is the most important information you need before making your own choice based on your situation:
What RPM’s do you want to be cruising down the freeway at and at what speed. Think about that hard, and go drive the car. Drive it for 2 miles at 3,000rpm…..it will most likely drive you crazy. If it does, you want to make sure you don’t get a gear that will put you in that range. I have mine set up to run at 2400rpm’s@80mph. I wouldn’t want to spin it any higher than that even if it costs me a bit of acceleration.
Depending on what the height of your tires have I'll bet you will want 3.55's or 3.73's to get a comfortable cruising RPM.
I run a 3.55 and couldn't imagine wanting to gear my car shorter than it is. I do have a screw blower though. 1st gear is worthless, I just punch it and have to shift right away and 2nd gear will haze the tires even though I have some seriously sticky rubber. Shorter gearing wouldn't get me going any faster....faster. It could possibly even slow me down.
Even if you don't have a blower but have stock-ish tires (high performance, all season about 235-245mm wide) you will still light the tires up something good in first and have to go for second super fast which makes that gear borderline useless. You will still lightly spin the tires most of the way through second too (if you make the 1-2nd gear shift fast) which lessens the effectiveness of that gear too. Which will slow you down.
When I had my stock 3.31's and stock Pirelli tires (about 75 miles ) I could SPIN the tires all the way through 2nd gear if I wanted too.
Use this gearing calculator. It will help you pick a gear for your situation. Use the # .71 for the auto trans ratio and .68 for the 5 speed. You will also need to measure the height of your rear tire at the right pressure sitting on the ground. You can keep firing numbers in till you find the gear that gets you the cruising RPM that you are looking for.
sqidd you are a scary dude ... you provide good info with facts to back it. You are like the Captain Kirk of motor vehicles. Thanks for your information which has helped me make informed decisions which I would have otherwise acted on impulse.
__________________
______________________________
2005 GT Convertible
"Old Skool Bod with New Skool Mods"
Thanks for the info. I realize the ram air is just for looks. But I will admit, it looks good. Especially under the hood with the rest of the dress up. I have avoided changing the gear in the rear b/c I do a decent amount of highway driving. Thanks again
"Ram air is a myth. What you have at best could be described as a "Ambient Air Duct". That hole in your hood you have would need to be at LEAST 12" higher off of the hood to get anywhere anything resembling "Ram" "
Good grief, someone who understands Laminar Air flow!!!! Good job Sqidd!
Thanks. So what's the next bolt on with the biggest bang. I already have the air intake, ram air, under drive pulleys, and custom tune. I have not done anything to the exhaust except after the cats.
Supercharger
__________________
`06 Redfire GT Premium Coupe,398 Stroker,Whipple Supercharged,Comp Cams, Ford Racing CNC ported heads & throttle body,4:10`s with Eaton posi,Moser 31 spline axles,5R55S auto trans w/billet 3500 stall converter by Level Ten, TCI ratchet shifter,BMR K member ,A arms,trailing arms & drive shaft loop,aluminum drive shaft, ,BFG KDWS`s on Am Racing,CDC chin spoiler,Roush rear wing,custom roll bar by JW Racing & fabrication Shelton Conn, engine & tuning by Jannetty Racing Waterbury Conn.
Thanks for the input guys, I appreciate it. As for the Ram Air, it is all semantics. The kit says Ram, the hood says Ram, the paint under the hood says Ram, therefore I call it Ram whether it does anything or not. Some things are done just for looks. As for laminar air flow, I studied that 20 years ago. No need to go back now.
Used throttle bodies 2005 Mustang GT 
):
