348/409 Bypass hose question

I have a 348 that I recently installed a stock 3x2 intake (set up by ****ster27, thanks ****), My question is can I plug the intake byp*** port and the water pump outlet port and not run a byp*** hose? I need to know if by plugging them off will the engine temperature be a problem (run hotter)? The tri-power intakes port is offset and dumps on the right side of the engine and the original 4 barrel port was straight forward and a simple 90 degree hose was an easy hookup. I cant find an original 3x2 fitting and have had trouble finding a 90 degree fitting 1/2 pipe to 5/16 hose end to install. I am not running a heater and am thinking of plugging the byp*** system off. As I understand it the byp*** works to provide temp to the thermostat. Feedback needed (especially from any of you who have plugged the byp*** hose system on your engines.

Thanks
Dan

 

I have run a BBC with plugged byp***, but I drilled the thermostat to have some water flow. Blower intakes don't utilize the byp***. Some water flow is necessary to prevent hot spots. You can also remove the center of the thermostat or by a restrictor plate. If you are not running a heater I doubt you will notice the longer warm up..I say plug it and try it..

 

I have mine plugged and been driving it for 4 years now and never had any trouble not even when idling in a line. Just plugg it.

 

Many years ago I bought a polished aluminum water pump from Lamar Walden (348/409 Guru) and when he had them cast he eliminated the provision for the byp***? Motor seemed to not know the difference.

 

Thanks all for the replies, I am going to plug them off.

Dan

 

Byp***'s are designed to keep the coolant circulating through the engine when the t-stat is closed. That keeps hot spots from forming in the heads since that's where most of the heat comes from. The heads are far enough away from the t-stat that they could be many degrees hotter by the time the t-stat opens. I wouldn't take a chance on harming even one cylinder on a cl***ic engine like a 348 or 409. I run nailheads and they just cost too damned much to repair.

 

I just ran into an issue with the 409 in my 38 Chevy coupe g***er so I thought I'd revisit this thread. I changed from an electric water temperature gauge to a mechanical one and wanted to have an idiot light also so I removed the byp*** hose to use the only available water port on the intake for a sending unit. Went for a drive right after and noticed that the temp would jump up to 200-205 before the thermostat would open. After the thermostat opened the temp would drop down to under 180 then the cycle would start over again. I did some constructive plumbing and hooked up the byp*** along with the sending unit and now it runs at a stable 180 degree temp without all the fluctuations. So my vote is to retain a byp*** hose if your cooling system is designed for one.