Datsun Roadster Forum-311s.org

We looked at making them, but yes, most agree they aren’t necessary and a repro would cost
several times the price of a good used one.

In the mean time, we have plenty of good used scoops if anyone feels the need. Pm/call/text/email!

My recollection from back in the day was that on the road cooling was always adequate. It was when in traffic going slowly or stationary that overheating would occur, and of course the deflector is not helpful without a little speed.

Do you have reason to think you need one? I'm with Jim, I doubt the scoop is a necessity.
Dan

I noticed that my roadster was pretty open in front of the radiator when I replaced the steering box and idler assembly. Not sure what was missing I looked in the parts manual then perused the forum for any information about the air guide.

Read some posts where folks were concerned about their engine temperature reading high, and the air guide/deflector/dam/lower scoop came up as a subject of question of whether it was installed or missing.

I just wanted to be sure that it wasn't an essential part of the cooling system.

The manufacturer chose to design, manufacture and install it for a reason.

rwmann wrote: ↑Sat May 15, 2021 10:43 am The manufacturer chose to design, manufacture and install it for a reason.

Yes, there are lots of other quirky,poorly designed borderline useless things on a roadster too.

-the s-brake light switch bulb checker-silly and never repeated to my knowledge.
- the early "rubber gasket" horn spring- a 5-year old could have done a better job designing that-again, Nissan dropped that in 68
-the evil L- idiotic and never to return fortunately
....its a long list

Still they are great cars and perhaps the above adds to the charm-(except the evil L)

The air deflector certainly does not hurt anything (although it can be annoying when the fasteners rust solid) but there is literally
a gale force wind coming through the grill at speed- so the deflector is hardly necessary.

As pointed out above, the scoop does zero at low speeds. We have had lots of cars that don't have one. Omitting it will not cause overheating unless-perhaps-your cooling system is in really bad shape.

If you live in the desert, I would probably keep it in place, otherwise, no issue - but hey, its just personal pref. Bolt it on. If you want a good one, we have them..

What's the evil L ?????

roysuecan wrote: ↑Sat May 15, 2021 3:17 pm What's the evil L ?????

U20 Upper Timing Chain guide, me thinks

There is an l shaped arm on the upper timing chain pulley of a U20. I believe the idea was to put a screw thru it into a threaded hole in the end of the cam so that the upper socket will be held in correct timing position when changing the upper chain.
The problem is that as the chain wears it begins to wear against the L and grinds a part away until the L breaks off and falls onto the crank below it with disastrous results.
Bad idea, not repeated afaik.
Dan

I have seen a difference when not using a mechanical fan, my electric fan seems to cycle noticeably less with one installed.

I run a 4-inch sacrificial, plastic lip on the deflector, backing up and extending below the center cutout on the BRE ‘cool spook’/air dam. The 14-inch SPAL fan (replacing the crank-driven/thermo fan) rarely kicks on other than at rest, after an extended run.