Hi all,

So I've had an 03 plate st170 for around 3 years now and am thinking about some mods for it to hopefully give the girl some more go. I'm really after some advice on whether doing any/all of the following is really going to be worth it (power/driveability increase Vs money), or whether I may be better saving up for an ST225? Before I list what I'm considering I should say that I already have a K&N panel filter and a bluefin unit (took the bluefin off last year as it was making the engine sound really rough..) - apart from that it's standard.

So here goes:

Milltek CATback exhaust
Sports CAT
CFM 67mm throttle body
Underdrive pulley kit

After a quick look online I'm probably looking at around 1500 all told for the above, is it going to be worth it or can anyone offer me some other suggestions?

I really just want to give the girl a new lease of life and try to add a little bhp in the process.

Please help a tuning noob out here....

Any answers much appreciated,

Nick.

 

Don't bother. It's very difficult to get any gains out of the st170 unless you are going to go down the forced induction route, then you are into the thousands of pounds!

I sold mine and bought an ST225, quick remap, change of ehaust, intercooler and induction kit and it's knocking on the door of 300bhp. Best thing I ever did!

 

Do the underdrive pulleys make much difference thinking of it for mine

 

i would look at exhaust, decent cams, and cold air induction kit, then a remap last, you should see near enough 200 brake and would feel better to drive as well

i wouldent bother with the pulley's or throttle body

 

I have underdrive pullies on mine, engine pick up is instant but i have an aluminium fly also.
Wouldnt bother with cams, you would have to lose the VVT to fit an aftermarker inlet cam, the likes of Piper etc reccomend removing this as they are a fricking nightmare to set up without bending valves.
Apart from an Sports CAT i have everysingle bolt on mod you can by for the ST170, last RR mine made 189bhp, was it worth it............no do i wish i had spent the money on a ST225...........yes.
Dont get me wrong the car is fun to drive but its not quick in todays standards. Yes you will show up allot of the rep mobiles but the most fun you will have is round corners.

 

I've got a k&n induction kit,a sports exhaust back pipe (no back box) and was thinking about fitting a decat and the exhaust vernier pulley but not sure what to do now??? Would you suggest any particular mods for one of these then?

 

Having a lightened flywheel and stage 3 clutch fitted is the number 1 thing that transformed the car, yes it chatters at idle but acceleration in 1st and 2nd is greatly improved 0-60 sub 7 seconds, i have an uprated gearbox mount and CFM short shifter which helps also.
I wouldnt bother with a decat, they really make the exhaust note raspy and it will also make your ST170 very loud.
Exhaust vernier i would say is probably worth the expense if you do the work yourself. Apart from that i wouldnt waste your money.
Your could always port the standard TB for free which i have done to removed the big hump before the butterfly, wont give you extra power but if i so much as breath on the accelerator pedal the car takes off now.

 

i dont suppose i could be cheeky and ask for more info on the ported throttle body, how isit done and whats the gain, thanks

 

I was just thinking that lol,think I'll port my throttle body. Is there actually any gain from a decat on one of these??

 

There are absolutely no power gains to be had from porting the standard throttle body but it will improve the responce, the throttle will become very sesitive and snappy so should allow you to get the power in quicker.
The standard TB is plastic all you do is remove it and as you look towards the butterfly you will see a hump that restricts air entering the TB at part throttle, the aim is to get rid of this by griding/sanding it away till the TB is completely round again, DO NOT touch any material around the butterfly, if you remove material in the wrong place it will allow air around the butterfly and will mess with the idle speed. The walls of the TB are thin so its sometimes worth moulding some liquid metal to the back of the TB where your removing material incase you break through the wall, when i did mine i never broke through i just took my time and sanded it nice and smooth, once you look at the TB its self explanitory.

A decat will give you an extra few horses if you can put up with the noise and the hassle of swapping it every MOT, you will get an EML with a decat so will need a MIL eliminator or get a dreamscience map which can tell the ecu to ignor the rear sensor.

 

Im a mot tester so the decat pipe is no big problem for me. I dont think I will bother if it makes them raspy though. Are the bluefin remaps any good?