Upper valve covers

[denson]

Confused!!

For a 1970 S are the upper valve covers supposed to be aluminum or magnesium? Is one better than the other?

I have seen some cars with them in black. I want the oem item so I am trying to get this right.

Thanks

[YTNUKLR]

Originally they were magnesium. I'd say aluminum is better for performance (leak) but it's not a big difference..

I have a good pair of the mag ones for the cost of shipping

[denson]

Should I go with the magnesium covers? I think they are more prone to leaks. Or, is it best that I locate an aluminum set?

Thanks,

John

[Chuck Miller]

John,

The valve covers on your car were mag. By now almost all original covers have been replaced with aluminum. The mag are about 1/2 the weight but were prone to heat warping. One had to spend lots of time sanding them on a perfectly flat surface to get them back... then they would warp again. The factory replaced the old mag covers with thicker alloy and the warping problems went away.

You can get new alloy covers, bead blast them (the new ones are pretty roughly casted), and powder coat them black and they will look just like the old mag covers, but without the problems....

Hope this helps,
Cheers

[denson]

Hi Chuck:

Thanks for the reply. Sounds like a good idea, but I thought the valve covers were not painted and were a bare finish. If that is true, and knowing that the magnesium covers leak, would I not be better off locating a good pair of aluminum covers and installing them?

John

[70SATMan]

... but I thought the valve covers were not painted and were a bare finish.
John

Mine are bare finish after its first engine drop.

[Mycar]

As Chuck says, little point in straightening warped mag covers, they`ll only warp again and if you lap them too many times the valve gear will start to knock(smash)into the back of them

I`ve recently replaced both my uppers and lowers with `turbo covers` as featured in Wayne Dempseys 101 things to do. I got the new (reconditioned) covers on ebay from somebody called EBS Racing like this.

http://cgi.ebay.com/ebaymotors/Porsc...Q5fAccessories

(No affilliation, by the way.)

Both uppers and lowers were stamped with original part numbers and reground flat. The lowers were raw alloy finish, the uppers were nicely laquered. The only dissapointment was the uppers don`t have PORSCHE cast into them like the early covers.I guess these are from a much later car but they fit perfectly.

I used reusable orange gasket, which, a week later saved me a load of money, when I spent the weekend doing the Hokey Kokey with the distributor. It`s pretty useful to be able to whip the lefthand cover on and off to find TDC on number 1..... time and time again.

I also found that you don`t have to drop the oil out of the engine to replace the lower covers. if you remove the wheel on the side you`re working and jack the car high from the side, you loose a bit but mostly it`ll run over to the other side of the engine.

Regards, Mike.