Greg86andahalf

My car came without a belly pan and I bought a new one. I can't see how the belly pan on my 86 is going to stop any type of medium to major undercarige hit from doing damage. The thing is lightweight metal and will bend easily. I see it as more of an important air shroud than a structural piece.

It would be nice if there was something available for the pre-87 cars which had some strength to it. If you don't have one, you should buy one. Sometimes 928 intl. has used ones in decent shape around $60, they didn't when I needed one and I got mine from DR for about $130.00

Greg

Bernie

Cool Thread,

Pun intended.....

I'll keep lookin'

Thanx For All the input.
Topic actually became quite informative.

Cheers

<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

Max

JMO, but I don't see how they would add to under hood temps. As Wally clarified, even at idle or low ground speeds they help with air circulation. This would lead me to believe it is more of a convenience for the mechanic and not in the name of proper automotive healthcare.

Pierre, maybe you could start gathering up all the 928 belly pans you can find in S.A. and ship them to the US for all of us silly Americans that think we have a use for them

Correction:
I misstated the number of ducks that factory pan has, it looks to have three ducts (pictured in the PET5). One on each side of the motor and one at the rear, it looks by the picture that the rear duct may be to direct cool air into the front bell housing. Maybe Wally can shed some light on the true purpose of the rear duct.

Bernie, yes it is funny how a simple “parts wanted” thread can evolve.

Cheers

Max

Bernie

I think it would be interesting to put Wally's comments to the test.

OK hands up - how many people have standing temperature problems with or without the belly pan.

This will give us a general overview as to what may be the cause for temps creeping up when cars are idling in traffic and such.

My '85 runs stone cold at moderate highway speeds, lets say 55mph but standing in traffic, the needle slowly creeps up. Now, could this be due to the missing belly pan or not?
Hmmmmmm......?????

Greg86andahalf

Bernie,
Interesting question, but I wonder how many accutate temp gauges there are out there. Mine runs in the middle. I just don't know if I can trust it!

Greg

Max

I’m not sure if you would see the differences on the gauge. Again, JMO but, I think you would see the difference from parts like the motor mounts lasting longer from some much needed fresh air keeping them cool (they are very close to the exhaust manifolds). I can only guess that the fresh air being ported into the front bell housing would prolong the life of the rear main seal?

Cheers

Max&lt;-- Just tiring to see it from a German engineering stand point

Bernie

Hmmmmm?
According to Wally, the hot air from the bottom of the rad will get recirculated through the front of the rad again. Sounds to me like that would mean overall fluid temps would go up. This would probably hinder the engine from staying cool while standing since the hot air is not being pushed away from the car? I think I will make some notes on my temperature and then when I get the pan on, I will recheck under the same conditions to see if there actually has been any improvement.

Andrew B.

Ok, another point is aerodynamics. A regional racer here in the northwest was mentioning his track runs with and without belly pans.

It's a hassle to get around the belly pan when you're working underneath the car, BUT when you're on the track it improves your aerodynamics dramatically.

The scenario is same track and runs with and without the belly pan.

With the belly pan he's at 168MPH, but without he says the car is at 155MPH. These speeds were at the end of straights of course, but if the difference is that much on the track you're looking at approximate 10 second difference after several laps (I believe those figures are accurate).

So...$300 for a belly pan...10 seconds. Easy math is $30 a second! Not bad...considering some mass production cars spend a lot more for that much time shaving!

Oh, you have to have a front spoiler, or else your pan works like a dirt scoop.

-Andrew
'84 928S

bergstsm

Bernie,

Another thing would cause your temp gauge to slowly creep up is a worn out fan clutch. My car had the same symptoms, which I learned was because the fan clutch was not engaging properly. Turns out, all of the oil had leaked out of the clutch.

Might be something to look at.

Shawn

Max

Bernie, Wally's right without a doubt. My previous statement was JMO, dealing with a 928 in forward motion.

I should have said “I’m not sure if you would see the differences on the gauge (out on the hwy)”. I apologize if my statement was misleading.

My hand is up Bernie!

My car never got hot driving around town or stopped at a lights. It has been when I was out on the hwy, before I put the lower spoiler back on (+ a few other little things) the car would creep up to the last white line at 60MPH or so, now I can run at a steady 80 before it starts to climb. Marc at DEVEK has told me more than once I needed to install a remote-motor oil cooler and By-pass the oil cooler from the radiator (Porsche did this on 90 or 91 up 928's). I am having a hard time figuring out were to put one <img src="graemlins/c.gif" border="0" alt="[ouch]" />

Cheers

Max

Andrew B.

I read on previous postings that oil weights have a role in summer temperatures. I use to use Synthetic 10W-30 in the beginning of summer and my temp would always be close to the upper lines if not in the middle.

Then after I read the posting about oil/cooling I changed oil at 5K and went to the synthetic 20w-50. What a whirl of difference. My temperature stays below the center and only reaches the center if I'm stuck in traffic and I my AC fully on.

-Andrew
'84 928s

soontobered84

The PO of my 84 Euro S ran without a belly pan. He ran over something that kicked up into the engine and knocked the A/C compressor off the block. It left a very nice hole in the side of the block. The engine is going back into the car in @ 2 weeks. I will have a belly pan.

DHughes

I just installed the Devek belly pan on my '89 S4. The aluminum pan is very substantial and will certainly fend off any street debris. I will also say that at highway speed, the car appears to be running a bit cooler--a needle width or so.

On a side note, my AC had quit on me and after much testing I discovered that the guy who installed the new CD head had disturbed the wires to the HVAC controler---reseated the plugs and all is good to go.

DH

Max

DH, every nettle width counts I’m glade to here your happy with your new pan/skid plate. I feel one maybe come my way sooner than later.

It's kind of like race weight; it's easer to find 100 places to take out one lb. than one place to get the same.

Today, I working on trying to figure out how to diagnose/check the water temp gauge and sender on my 89 for accuracy, I am almost sure mine is off.

Mike Schmidt

Let us know if you find out anything on the water temperature gauge/sender stuff.