Beast

Guys, I know there probably have been many threads pertaining to these questions but to save time hunting them down I thought I would just ask again. I have 06 GT and have added the Roush exhaust, CAI, and Diablo tune. I love all of it. What are the dangers, if any, of adding Underdrive Pulleys? I also want to lower the car slighty and am considering Eibach springs. Are there any problems just adding springs only?? Do the struts etc have to be replaced also? Thanks all!!!

s197richie

there are -0- dangers/ downsides for UDPs. But it's important to follow the torque specs outlined in the instructions. That's all.

Don't know anything about lowering a car. Sorry. F1 Fan I believe is the guru for that kind of stuff.

any other mods you're planning? Gears, kmember brace/torque limiters, shifter etc?

Beast

Good question! After pulley's I dont know of what else I can do to increase hp without going into the motor. I have the 18 inch bullit style wheels but I'm thinking about going to 18/10's all the way around in a style resembling the stock wheels. Too bad Ford doesnt offer the ones I have in a 10 inch. I like the style. Thanks for your reply!

s197richie

big hp increases (FI or heads+cams) are mega bucks for these cars. The only hp increasing mods I've done are the UDPs (maybe 7rwhp), CAI/tune (up to 30rwhp so they say), and the o/r x might have gotten me another 5 or so. The 4.10s made a hell of a difference. As far as preventing any damage to the vehicle, my steeda rear ca's and che kmember brace/torque limiters will prevent anything being broken due to wheel hop or the binding that occurs between the trans and the body-mounted shifter.

The throttle bodies seem to be a total ****, the delete plates offer minimal gains also, and the axlebacks do nothing, hell they may even subtract a ft/lb or two. Shorty headers are worth next to nothing, and long tubes are very expensive for the gains they offer, esp. if you're paying a wrench. Some even say the heads+cams aren't worth the dough, so I guess twin screws is where it's at

Beast

I like the idea of going all out with the sport eibach suspension but its a bit pricey for now. Maybe in a few months. I was thinking about doing just the springs now but I want to be sure there wouldnt be any problems with the rest of the suspension if I just replaced the springs. Did you put you pulleys on yourself? What wheel tire combination are you running?

rshamekh

You can do just the springs but the ride will get worse with time.
What's necessary:
-springs (eibach as u said), the pro kit will give u a mild drop around 1.4" while the sportlines drops 2" which is a PITA for a daily driver and for balancing ur tires and clearance issues.
-Shocks and struts (Tokico d-specs are known to be the best out there)
-panhard bar and brace (to re-center ur rear, because it will be off by 0.5" or so, each car is different)
-Alignment after installation

You can find 18X10 bullits on www.americanmuscle.com but they will only fit on the rear, u should go with 18X9 for the front.

rshamekh

Oh and performance wise, u might want to get a custom tune instead of ur canned one.

Chevy Convert

Get a custom tune from bama or brenspeed and some gears and you are set. After than go after some rear suspenion upgrades - LCA's primarily.

Beast

Wow, so you guys are not impressed with the Diablo? Thanks for the info on the suspension! I calledSteeda today (not sure between Steeda and Eibach) and asked about the springs only and they told me that it would be fine with no ill effects except that I would want new strut tower braces for alignment purposes. When you said the ride would decline with time you mean 20k miles 50k miles?? Thanks again!

rshamekh

Not sure exactly but many members were saying that the ride got worse with time.
And eventually they got the D-specs. And most of them regret it and wish they did it all at once.