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Can someone explain decklid venting?
sax - December 19th, 2004 at 01:37 PM

Now I know that early bugs have non vented ones, later ones have some or more.

I thought the vents came about due to the extra heat generated by the larger donk, but how come some modern kickarse type1 motors will run ok without them in early beetles ?

What is the signifcance of the engine bay seal around the motor if some people run stand offs (which I hate the look of)

I guess what I'm asking is are decklid vents needed at all and if you run a gutsy motor in a hot climate how do you keep it cool?

They look better without but I wonder if that is healthy for the motor.


phantom - December 19th, 2004 at 01:52 PM

Yes I'd like to know this too, my '60 doesn't have any vents but I am going to put in a larger engine and want to know if I have to vent the lid?

Can you 'cut' vents in without ruining the paintwork?


Che Castro - December 19th, 2004 at 03:41 PM

the factory fitted vents to the decklids in '70 onwards for the 1500 engine and then the 1600. The doghouse fan needs a lot more air than the 1200 fan so it makes sense. IMHO i think they are essential to have them to match the motor. Otherwise if there is too much restriction for the fan it will just suck up hot air from underneath - this is where the engine bay seal comes in. It seperates the engine compartment into the upper (cooler air) and lower (hotter air where the exhaust and fan air blows into).

Its essential to have a the seal in place and no large gaps between the upper and lower parts otherwise the fan will recirculate hot air and you may overheat.

To make vents in an early decklid isnt really that hard. I'm doing this to my early decklid by cutting out the vents from a '70 decklid and grafting them in. They vent cutouts are stepped along the edge using a stepping tool and then spot welded into the decklid.

This plus also cutting a big rectangular hole where the licence plate usually goes over to get even more air.

Other option is to actually find a real cabrio decklid (near impossible in Aust) or to get one made from fiberglass or carbon fibre.


68AutoBug - December 19th, 2004 at 11:48 PM

Yes, Jon is correct with what He says....
I have heard of 1600 engines with a 1500 engine lid getting hot in summer high temps....
so its best to use a SuperBug engine lid or use the Stand offs
which do make a lot of difference to a Hot engine...
I have heard 10-20C degrees difference.... for stand off lid...
depends on the engine and ambient temperatures naturally..

The stand off equipped engine lids actually force air coming from over the roof - into the engine bay...
much better than the pre heated hot air under the engine -
ie. below the engine compartment seal....
Its most important to keep the hot air below the engine...
as Jon said....
If You have a 1500 engine its best to update the cooling with a late model fan housing and doghouse oil cooler & wider fan...

Best of Luck..

Lee --





[Edited on 19-12-2004 by 68AutoBug]