Technical Water Pump Dilemma

Dear H.A.M.B.er's

Just received my new Stewart Stage 2 pump Model # 22301 for my mildly tuned 327 SBC (circa 1965). I bought the aluminum pump as I thought it to be the best way to go and not have to worry about a water pump for the long haul.
In doing the dry fir I noticed this pump does not have a water bypass (small open port on the passenger side of the water inlet).

Stewart says that this by pass is not used on their high performance Stage 2 unit.

So the question is: do I need a bypass for usual street driving/cruising?
What are the downsides (if any) for using this pump on the street?

Appreciate the expertise this group always offers.

MrPhat40

 

Do you have a heater in the car? Does it flow all the time?

 

I have never run one on any of my many sbc's. Never a problem. Heater or no. Maybe I've been lucky for 50 years.

 

Stage 2 pump shows to have the theaded hole for the heater hose connection in this shot https://www.summitracing.com/parts/emp-22103/overview/ What it doesn't have is the normally plugged outside of some truck applications bypass connection on top.
Most stock 327 iron pumps I have seen come with the bypass hole on top and with a plug in it. I don't think in the past 55 years I have ever hooked up a bypass hose to one. Like this one if the O'Reilly's link works. https://www.oreillyauto.com/detail/...6144/1964/chevrolet/impala?q=Water+Pump&pos=1

 

Drill it or exchange it.

 

Actually I was referring to the by pass hole as shown in the picture posted by Johnny Gee.
Do I need this opening for a street car with a heater?



Sent from my iPhone using The H.A.M.B. mobile app

 

It helps by giving water a chance to move when thermostat is closed (cold). In 55 the first year of SBC some vehicles came with out heaters so this by pass was done.

 

Does your system have full flow of coolant or does it have a heater valve?

 

Are you using a thermostat?
I would drill a 3/16 hole in the thermostat. Creating my own bypass.


Sent from my iPhone using The H.A.M.B. mobile app

 

The thermostat is a 180 degree high performance model from Speedway it features (3) 3/16th inch bypass holes.
So it looks like I will be okay with this unit.

My concerns are all due to the fact I need to trim the driver side mount to get it to clear the timing cover.
If I grind this pump in order to fit it I own it!!

Appreciate the explanation of the bypass.
MrPhat40



Sent from my iPhone using The H.A.M.B. mobile app

 

Reminds me of the time my Dad went to White Front to buy shoes and come home with a stereo unit instead.

 

what long haul? aluminum corrodes too, unless running a clean sacrificial anode

 

Where to get and how to install sacrificial anode? I'd like to install one in each of the cars I have with aluminum components in the cooling system.
As for the bypass, my sbc powered '31"A" Hiboy utilizes a Zip's water pump riser which omits the oem bypass hole and the instructions that came with it were very emphatic about the necessity of a bypass hose if there wasn't a heater with constant flow on the car. The hose runs from an outlet on the pass side head to the nipple cast into the water pump housing.

 

Great point
At this point in time I am returning the Aluminum Stewart for credit
Looking into their cast iron unit.
Appreciate your comments
MrPhat40



Sent from my iPhone using The H.A.M.B. mobile app

 

simple install - one from Flex-A-Lite replaces radiator drain plug, Scott Drake & Northern Radiator offer radiator cap replacements