Author Topic: thermostat bypass for vortec heads  (Read 9787 times)

Offline rhagoki

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thermostat bypass for vortec heads
« on: December 03, 2011, 03:18:39 am »
Running vortec heads and intake on a small block instructions from intake manufacturers as well as online forums seem to say that you should run the bypass if you have a vortec block. My question is for those running a pre vortec block with the bypass on passenger side of water pump below mounting hole. If the heads themselves do not have the hole in them shouldn't all vortec setups be running the bypass from top of water pump to front of intake? 

It seems running heater hose by thermostat housing acts as bypass of sorts, but what would running the bypass in addition to heater core and bypass in block by water pump affect? 

Offline VileZambonie

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Re: thermostat bypass for vortec heads
« Reply #1 on: December 03, 2011, 02:08:21 pm »
Coolant needs to ciculate through the engine not the radiator when the thermostat is closed. Coolant needs to circulate around the cylinders and combustion chamber area, through the inake and heater core. That is why you need to run a bypass circuit because of the design of the intake/thermostat. What intake are you running? I'm pretty sure I posted the hose part # needed and how to do this in a few threads.
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Offline rhagoki

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Re: thermostat bypass for vortec heads
« Reply #2 on: December 03, 2011, 04:12:28 pm »
I'm running gmpp intake, not sure of which # off the top of my head.  I've read several posts on coolant flow as well as your comments on a few of em and im still stumped on this one.  Stock heads have the bypass circuit hole and therefore can move the coolant pre-thermostat.  On a block that has that bypass hole, but the vortec head does not, how then does it move coolant pre-thermostat?  It seems any block with vortec heads should use the bypass circuit on front of intake by this thinking, am i wrong?

It ran on the hot side in the summer and I drive about 6 miles <45mph now that it's cold before it gets up to the first hash ( 160ish?)  and that's about the warmest it will get.  Thermostat is new 195 and was working fine in boiling water.  I know that temp sender being in the front of the intake might read lower than coolant in heads and such when the thermostat is closed.  I have heat coming out the vents as soon as needle starts to rise.  I would rather have the engine running at optimal operating temperature ( im guessing somewhere around 185-200 since stock t-stat is 195)  and have the coolant flowing properly regardless if i'm having problems or not. 

Offline TexasRed

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Re: thermostat bypass for vortec heads
« Reply #3 on: December 04, 2011, 10:19:56 pm »
Uhoh. I haven't been running this. I've put a few thousand miles on the mill but I'll add it. I did have a slight ticking, maybe that was the water pump that was driving to move nothing? Did I do some damage?