coolant passage ways

[s30z_lou]

do we really need the rear engine bypass tube, rear water outlet, engine side water tube, hole on the water inlet tube, and the coolant passage way through the intake manifold for su carbs to the thermostat housing?

This is with the heater hoses already out.

I plan on deleting the hole shaaabammm.

does anyone know the thread sizing for the above mentioned so i can go to my local home depot and by some brass fittings to plug those holes in?

[beermanpete]

We bypassed all this on our car with no apparent problems. The only consequence is it takes a long time to warm up enough to be drivable. For a track car this is not an issue, for a street car it can be annoying when in a hurry.

I do not remember the thread sizes.

[LeonV]

Don't need it. I removed all of mine and have no warm-up issues. The exhaust manifold warms up the carbs before the coolant even has a chance to. I don't remember the sizes, but they are very likely all BSPT fittings, not NPT. Good luck finding that at home depot! You may be able to get away with using NPT and teflon tape, but it's much more preferable to use the proper fittings. You can find them online at sites like McMaster Carr, or possibly at a specialty hardware store.

[Walter Moore]

If you ever drive the car in cold weather the heaters help.

The hole in the housing is 1/4" BSPT. The local hardware stores generally do not stock BSPT fittings. McMaster Carr carries them, and they can be ordered online. You might be able to get them at some of the better auto parts stores (NAPA) but the bulk stores will just give you a blank stare.

[Oiluj]

Bypassed them on my previous car, and in temps below 50 degrees F, I noticed it took longer to warm-up. It was very noticable when the tem dropped to around 40F.

[s30z_lou]

thank you Walter and everyone for the info.

i currently live in central valley california and it's about 80f to 100f

around here. no problem warming up.

yea i hate it when i go into an auto parts store and they give me that "i don't know **** about cars" look, but still able to get a job there.

does anyone also know the fitting on the thermostat housing?