Undertray on my 03STi is getting a bit tired being on and off so many times for frequent oil changes (track use). Also it takes longer to remove and refit than the oil change itself. Does it serve any particular purpose or can I leave it off. If left off I'm sure engine would run a bit cooler.

Possible purposes:

1. Keeps engine clean, I'm not particularly bothered.
2. Controls aerodynamics under car, which I doubt.
3. Influences air flow through intercooler ??
4. Other ??

Any views.

Cheers, Diccy.

 

If you remove it, you will lower engine tempretures.
It could affect the airflow of your TMIC tho....

All IMO of cause.

 

Lol, it shouldn't take long and is easy enough to do. I balance it on my head whilst I pop front and rear clips in, the just bolt up. 2mins to get off and 3 to get back on and thats on my back on the drive..

I take it you do have all the clips (iirc 4 poppers front and two u clips at rear)..?

Leaving it off has to effect aero IMO. Also, would there be a risk of thermal shock to the sump/headers if you drove through some water..?

 

Thanks for replies, jury sort of still out but sounds that I'd be wiser to leave on. Got all the clips but the front 2 bolts threads are worn and can only be nipped carefully, must get replacements. Perhaps I complained too much about removal but I don't have a pit and have to get car up on blocks to have enough room.

Cheers, Diccy.

 

Does it do anything?

Yes - it makes your oil change a PITA but you knew that already

 

Mine has come off to make way for the FMIC. Apparently it's not an issue; JDM classic often don't have them by all accounts. IIRC the mechanic said oil temps would probably be about 10 degree cooler without it, so that's a bonus.

Just don't use the car for any off-road antics!

 

mine has never had one since it came into the country!