On Drag car or street car. NO HEAT.

Do I need it?

Thanks

Yes, do you want stable engine temps? This is not for your comfort (heat in the car), but rather to circulate coolant through the top of the motor, where the heat is.

it allows circulation of the water during warm up. Prevents water pump cavetation..

On Drag Car...never have used it..plugged.

I block it completely on our stock car that uses NO stat tho I believe every other type of car needs a stat for the faster warmup not for a restriction & some amount of bypass & I use a piece of cardboard in front of the rad to effect a normal (faster) warmup tho the increased wear from a slow warmup is a non issue in a stock car that is operated 1 or 2 days a week but I'm anal & a perfectionist. I've always wondered why the SB's needed such a huge bypass as that is coolant that ain't gettin cooled in the rad and if you look straight down on a BB housing the bypass hole is only a fraction of the size of the SB one. There must be a good reason in the design of the SB cooling system that had to be done in a certain way cuz engineers ain't stupid tho they do design cars for Grandma to drive daily for 100K (not sure how that relates tho) so it must be related to the design of the SB system that it needs that much bypass. For street I use the anticav plate (plus a bunch of other cooling mods) & restrict the bypass to 1/2 of it's original dia plus a (180) stat

Depends if you have a thermostat or not.

As part of using Evans NPG waterless coolant
I bought a 17 mm Chrome plated 3/8th drive socket
and slipped it inside a new coolant bypass hose
and installed on my Magnum 360 V8.

This closed up the bypass passageway to a three eighths square.

I was hoping that the partially restricted bypass
would increase full throttle engine maximum cooling enough
to eliminate audible pinging
starting about 3800 RPM when using
87 Octane gasoline in
+95 degree North Carolina summer weather
climbing a 6 percent grade hill.

There was no change after the bypass restriction.

Switching from 87 to 92 Octane would totally eliminate the full throttle pinging.

Running straight water as coolant with no thermostat would also eliminate the pinging on 87 Octane.

Removing sparkplugs from Cylinders 7 and 8 and spraying in official Chrysler Combustion Chamber Conditioner foam in, then reinstalling sparkplugs would eliminate the full throttle pinging on 87 Octane, but only for about 3 to 4 days.

is the bypass hose not needed if you drill a few holes in the t.s.?anyone that runs a rpm airgap on a magnum knows what a pisser these are