Rear suspension heat shield

[Chris Mark]

I’m rebuilding my series 3 OTS which was reimported from the states in 2000. Having finished the Diff/suspension assembly I’m now ready to re install in the body. Having looked through the parts manual it shows a large heat shield above the suspension assy - which wasn’t there when I stripped the car. I know they are available to buy but is it necessary if I use dynamat or similar inside the car and heat lagging for the fuel pipes ? Does it assist air flow??
Any suggestions would be welcome

[kevh]

I am currently restoring the same model, when my car arrived part of the old heat shield over the centre silencers had broken away and the interior was heat damaged in this area only so I would say yes it does need to be fitted.

[lowact]

Not seeing any significant heat source above the diff?
You can see part of this shield in this photo with the irs removed, I wondered if the idea might have been potential noise attenuation?

[Bob.]

According to Norman Dewis notes, heat from the differential during high speed testing resulted in a boot floor temperature of 90°C. During Alpine brake testing the rears reached 420°C. The S3 has underfloor air scoops to try to direct cool air into the IRS region but it evidently needed the heatshield as well .

[christopher storey]

Those of us old enough to have been around at the time will remember how the early racing E types ( OTS) used to have the boot lid propped open by about a 1 inch rubber sandwich to assist in cooling the rear end. It is not just the rear discs which create heat - diffs themselves, if under a lot of load, commonly run at temps in excess of 150C

[lowact]

Wow, now I'm wishing I'd put more lagging on my fuel lines

[Chris Mark]

Thank you all for your thoughts. I’ll definitely add a new heat shield in light of this info.
Looks like another trip to Robey,Barrett or Manners to empty my wallet-again!!

[kevh]

Looks like another trip to Robey,Barrett or Manners to empty my wallet-again!!

I'll see you at their Christmas party!

[angelw]

Chris Wrote:

Looks like another trip to Robey,Barrett or Manners to empty my wallet-again!!

Hello Chris,
The After Market part is made from thin sheet aluminum with a textured finish pressed into it and has little resemblance, material wise, to the original. As well as serving as a heat reflector, it also serves as a noise dampener. The original part has a circa 6mm thick, dense foam material stuck to it's upper surface. The After Market part doesn't have this as supplied, but its good practice to replicate it.

Regards,

Bill

[rkellogg19]

Any concern that this heat shield could trap moisture between the body and itself and cause a rust issue down the road? I’m restoring a S3 and have been wondering about this part myself.

[kevh]

I wonder if the change of material used for the heat shields is due to the original possibly having contained some degree of asbestos as it would have been one of the go to materials for heat protection during the 70's.