whiteNSXs

Finally the car arrived via the transporter. The truck was not allowed to unload in San Francisco so I had to go to Emeryville to pick it up. Nice car. I got on the road and heard some thumbing sound by the left front everytime the car bounced. I got out of the car and checked but saw nothing. I figured it got some bad shock or something. As I finished crossing the Bay Bridge and heading towards the Golden Gate Bridge exit, I felt something big broke violently and the left side of the floor board felt it as well as the rear wheel going over it. After that, there was this loud scraping metal sound under the car. I was able to pull over once I got off the near exit. One look at the bottom of the car made me want to throw up. Apparently, at one bounce, the belly pan hit the ground and the front left section got torn away and the NACA metal duct was scraping the ground. Since it was getting dark and I was not in a very good neighborhood, I decided to just continue to drive home 2 miles down with that terrible scraping noise all the way through. Well, I searched the forum and tried to find a replacement and came across a few aftermarket sources with the aluminum replica. However, none seems to have the metal NACA metal ducts. I am hoping that there are other options other than the ones I found on the forum. So my question is: Who sells a replica that has the proper ducts? Are all the replicas the same? If there is no duct, are the 2 opening at the exact locations of the OEM one so I can just rivot the old ducts on the replica? One duct is quite banged up, so I would prefer an exact replica. The lowest price I can find is $279.

The first 928s that I drove 26 years ago were a 1981 European 928s auto and a 1981 European 928s 5sp. I was totally blown away by their power, handling, and the solidity. However, the 1987 928S4 that I have now really underwhelmed me in terms of power and handling. I figure the automotive world has had decades to catch up and has surpassed the mighty 928. To me the 928 was the most advanced and sophisticated car of its time. Well, at least I finally get to fix my 928 void.
Steve

sendarius

Yep, the replacements have the openings for the ducts in the same place - just drill out the rivets attaching the duct to the the old pan, and rivet the duct onto the new.

whiteNSXs

Your name is Steve and you like white cars? I have had 3 white NSXs, one white 911SC and this 1987 928S4 auto, you guessed it right, GPW with pearl white full leather interior.
Steve

Nicole

Hi whiteNSXs-Steve:

There is no aftermarket belly pan I know of that comes with the ducts. These are far too complicated to make, and are usually in good condition on the old, broken belly pan.

As sendarius-Steve says, drill out the rivets, and transfer the ducts to the new belly pan.

When you mount your new belly pan, make sure you don't forget any of the bolts. Lots of them there, including one each inside the ducts.

As to the underwhelming performance and handling - keep in mind that your car is now 22 years old, and if it's an automatic, it starts in 2nd gear. There arets of available upgrades, as you have probably seen here already.

heinrich

Bellypans serve no purpose

Nicole

Oh no - not this again!

A search here could find so many discussions on this topic... and you know I am one who doesn't agree with your assessment.

In a nutshell:

- lowers drag coefficient
- sucks hot air out of engine compartment
- cools motor mounts (ducts)
- keeps debris out of engine compartment
- adds extra time to repairs and maintenance from underneath

Hilton

Welcome

A well-sorted S4 still goes, stops and handles very well even against many modern cars. However, the cost of getting it to that well-sorted (i.e. as it left factory) level of braking, acceleration and cornering can be prohibitive without doing your own work, and many of them just fall further into disrepair.

Usually the best cure for a slow-feeling S4 is to get it back to factory power levels by repairing all the broken or non-functional stuff.

Chances are your S4 needs two new knock sensors and a new hall sensor - the ecu automatically retards all cylinders by 6 degrees if a fault is detected in either knock sensor or the hall sensor, which makes it a lot more sluggish.

The majority of 87-onwards cars out there still need all of the following:

Timing belt and possibly new sprockets
Intake manifold reseal and sensor replacement
Motor mounts and oil pan gasket
Ignition tune-up (wires, caps, rotors, coils)

Clogged cats is also a relatively common problem - you can recover, and then gain extra, horsepower with an X-pipe on the exhaust and some high-flow cats for it. However, best to add the X-pipe to an already ok car, so you realise the benefits

Mike Frye

Heinrich, I have to disagree as well.

I drove my car for almost 3 years without one and have a pretty good feel for what is 'normal' as far as the feel of the car and the gauges. Then I finally got a bellypan and installed it and noticed that the car consistently runs cooler. It used to run dead middle of the gauge (9:00) all the time. With the belly pan it sits there if I'm in traffic but if I'm moving even slowly it drops down to almost the first line (maybe 8:00?).

I can't vouch for the rest of the stuff, but that much seems to obviously be a benefit, especially since my AC fan isn't connected so I have no 'backup' if it starts to get hotter.

Bill Ball

You can still get a new original front bellypan with the ducts on it for about $325. I actually prefer it to the aluminumn aftermarket pan, but that's just a personal preference. I just got a new one after a couple of large road obstacles destroyed mine. It did a good job of absorbing and dispersing the energy of the impacts that might have caused more harm to the car's vital organs. Although the car will drive just fine in everyday driving w/o the pans, they do perform some valuable protective function as well aerodynamic functions at higher speeds.

Now, normally the pans will not contact the road unless there is a large hazard, as in my case, some of the bolts are missing allowing it to hang down and/or you car's ride height is way too low. Make sure the latter issue does not apply to you before you install a new bellypan.

Sounds like you are local (Norcal). Let me know if there is any way I can help you with your new car.

And, as always, with a new car, THIS THREAD IS WORTHLESS WITHOUT PICTURES!!

Nicole

+1

ptuomov

From where?

Rob Edwards

Tuomo-

I got one from Sunset back in 6/06 for $235 (928.504.021.02), they still had a few in Germany at the time. The first one they sent was broken, so caveat emptor if they find you one to ship.

whiteNSXs

The belly pan that was destroyed only had the 2 middle vents. The vent on the far right in your picture was not there. Is that an updated version or mine is just broken from day one.
Steve

Nicole

There was only one version of the belly pan. They all had the same ducts, as shown in the picture.

ew928

Edited.


Post pic of your car, whitensxs.
Be easy to tell if ride height is low from picture.

Crunched the bellypan once.
Never ever want to go through that again.