Wanting to eliviate as many unforseen problems as i could at the last trackday, i decided to remove the plastic under tray gaurd on the old Type R.

Before removal my engine oil temperature ran at about 85-90 degrees, after removal it has dropped to about 50-55 degrees. So a drop in oil temperature of between 30 and 40 degrees, all from a 2 minute job of removing the undertray.

Its probably been mentioned before, but i thought i`d mention it again as it must be a worthwhile and very cheap mod.

Paul

 

Paul,
Back in the 70's when I used to play at rallying, the first thing I was advised to do PRIOR to fitting a Dural sumpguard, was to fit a 13 row oil cooler with stat, to compensate for the loss of cooling caused by the sump guard.
I never had an oil temp gauge to see what difference the sump guard made, but from what you have found, probably quite a bit.

Cheers MTR

 

Paul,

Sounds like a good mod. but did you consider the change of airflow under the car and in/out of the bonnet holes ?

It is very complex and you may find that although airflow has increased in areas with regards to oil temp, that now, the airflow through the radiator has been decreased. Or maybe the push through/pull through effect on the intercooler has been affected etc ?

Just something to think about.

To be honest, you will probably find no problems at all, just wanted to bring that to your attention. This kind of thing can really affect some cars.

Cheers

Ian

P.S. Just reread that and not only is my English poor it reads like I'm taking a pop. I'm not, honest.

 

Guys this works, I have seen up to 40 degrees reduction in oil temp by taking off the undertray of any Scoob, some of you out there will remember me making that recomendation at the time cars were Linked, it does not affect air flow under bonnet, consider that all Sti "standard" models do not have an undertray, this was where I first noticed the difference ... up to 3 degrees of extra advance with out it !!!

Well worth putting up with the mud.

Bob

 

Bob,

This may seem daft, but what about having a vented undertray. Would this work?

The undertray on my GSI saved my sump once.

P.

 

Another thing to consider is that all Scoobs AFAIK have an oil cooler incorporated into the water radiator. If you can reduce the water temperature, this should benefit the oil temperature.

I added some Water Wetter (£18) to the coolant in my car about a year ago which resulted in the water temperature needle stabilising at a "ten degree lower angle".

I remember Bob telling me that the water temperature gauge is not proportional so it is probably only of a small benefit (but it all counts!)

Has anyone tried this with an oil temp gauge ?

Thanks

Gavin

 

Venting will help of course but the effect is partly achieved by the sump being in cool air thus helping reduce temp. As soon as the car stops and sits in traffic the oil is stabilised at the engine coolant temp by the oil cooler. Consider also that if oil is above coolant temp then coolant is heated by oil. If the undertray is essential for use then fit an oil cooler, as a road car the undertray is not needed though IMHO.

 

Hmmmmm.....I wasn't running a sump tray at Donno, and still saw temps of 210F. Under normal use it's generally about 180F.

Stef.

 

Thats 98 deg C (ish)and around 82 as normal, my temps are much lower than that, still not severely excessive, oil type/manufacturer varies in temp, Silkolene runs cooler than Shell Helix for example. With undertray that would have been well up. If track is prime use then oil cooler is obviously good.

 

Although it seems obvious that a removal of the sump tray will reduce oil temperature by increasing the flow of air round the sump, will this have knock on effects on the handling of the car. I understood the sump tray's purpose to be to smooth out the air flow underneath the car reducing drag and thereby reducing lift and making the car more stable at high speed.

ChrisW.

 

..and presumably, removing the undertray would also alow road spray to cause a repeat of the MY96 exchaust shield cracking problem?

 

What tray ???
I have never had one on my 98UK 5door since I bought it (ex demo). Did 5 doors have them ??
Stan

 

Walker!

What happens when you hit the Gravel trap hard? LOL

 

Road spray still gets in on the heatshields, makes no real difference, vibration kills them not water, air flow does not affect car handling, all Sti 4 door/wagon come without it (and WRX).

Its a simple thing, the evidence speaks for itself as per original post.

 

I'm gonna be whipping it out at the weekend!!
And I might take the Sump Guard off as well ........... boom boom!

 

Yep, it works for me, the evidence is clearly shown on the oil temp gauge!

Harj........no probs in the gravel mate

Akira.......glad to hear it mate

Later

Paul

 

StanS,

I have a 5 door and it has the under engine protection, so I would imagine yours should.

Just to mention a point, oil is designed to run at temperatures of around 80-90 deg C, or there abouts, and this is where it offers it best protection. Running with oil too cold can reduce the effectiveness of the oil with possible detrimental effects.

 

Spatch
Am concerned about engine parameters so hoped to get oil press/temp and boost gauges fitted to a centre pod. Looks like it could be expensive labour to fit, so am asking in "Internal" how easy to diy.
Stan

 

Stan

Let me know how you get on fitting the gauges as I am thinking of fitting some too.

Cheers

 

Spatch
The little red horns are appearing out of my head and I'm thinking of spending the gauge money on a DP instead. I'll get back if I get sensible and go for the gauges !!!!!!

Stan

 

Stan

Which DP are you considering?

S