i have 2 78 280s and a 76 280 the 78s have vents but the 76 does not. did vents come on them or are they aftermarket and what purpose are they

Hood vents were standard on the 77-78 280Z. Those hoods will fit the earlier S30s.

and what purpose are they

they let the hot air out from under the hood.

i thought it had something to do with vapor lock!

they let the hot air out from under the hood.

Do the hood vents really work?

I only ask because on my old MGA, high pressure developed by air piling-up on the windshield actually forced air "into" the cowl vents instead of air flowing out of the engine compartment.

I realize the Z's aerodynamics are certainly different than the MG's.

there has been a HUGE discussion of all sorts of aero on the "other site"

http://forums.hybridz.org/forumdisplay.php?f=112

Hood vents specifically, here:

http://forums.hybridz.org/showthread.php?t=122509

i thought it had something to do with vapor lock!

EFI cars don't vapor lock.

EFI cars don't vapor lock.

Lucky bastards! :tapemouth

EFI cars don't vapor lock.

thats what i was thinking

Some people will argue that point, however.

Since carbureted engines usually use a mechanical fuel pump located on the engine, they need to suck the fuel from the gas tank, and a bubble of vaporized gas can develop, which doesn't liked to be sucked through, and just gets bigger. This is 'vapor lock.' So you let things cool so the bubble disappears and you can suck gas again.

Since fuel injected engines use a fuel pump near the gas tank to push the gas to the engine using much higher pressure, you pretty much eliminate any vapor bubbles in the fuel line. You'd need a really REALLY hot day for conditions to vaporize fuel in the lines under the car, but it might just be possible, like if a fuel line was too close to an exhaust tube or muffler.

If that were the case, the ~37psi would push the air bubbles through and at worst, if everything else is working properly, you'd feel a couple of 'hiccups' and keep on going.