172 big bore throttle body

[Black Clio]

came across someone who makes a big bore throttle body for the 172 and selling for 783 pounds, anyone tried one of these out and how does it affect the engine???

 

[Man-Chun]

Ooooo sounds interesting. Anyone know anything about this?.

Thanks,

Chun.

 

[BenR]

heya, you will probably be the first!
problem with big bore bodies is that at low rpm the air moving through the throttle body and inlet port will be travelling slow, thus, cylinder filling and VE will be a bit poor and you will loose torue as mixture suspension will also be poor. You will gain more power at the top end of the rev range say 4000rpm and up, but toque will be crushed if the throttle bodies are too big, and if you do get it, make sure the inlet trumpets are as long as you can possibly fit as making already moving air move faster is easier than making non moving air move up to the same speed.

 

[Black Clio]

The inner diameter of the inlet is 70mm, which I think is about 13mm bigger than standard. Together with a induction kit and hi flow exhaust, I was quoated a min. of 10HP increase! But Im not too sure as someone else told me Ill need to get my computer remapped to gain such effect.

 

[BenR]

13mm!!!!!!
thats huge, you will get more top HP, but less torque!!!! i promise this, but the exhaust and induction will only make the gases flow easier not fater therough the engine. You will need to get the ecu re mapped because it will be affected.....dunno if its worth it, because you need torque in HK!!!

 

[Black Clio]

Thats exactly what I was thinking... maybe not really worth doing for HK