What are these 3 holes for on the intake ??
I have a Edelbrock Performer RPM #7111 on my '70 Rocket 350.
The 2 holes DIRECTLY on each side of the thermostat housing
have these HUGE plugs in them with teflon tape.
I don't know what they are there for.

The one labeled #3 has a sensor plug in it going to a mechanical
gauge inside my car. I can't remember if it's oil or water temp.

Basically I'm just trying to figure out WTF these are and where I can
get replacement plugs because mine look like dookie.


You can see mine here, I'm trying to find a spot for an electric fan temp sensor.

 

The pass side is for a ported vac valve, and driver side temp gage. I used the brass plugs, as they are good and look nice, if you are not using the holes. That extra hole on the ooutside driver,I think is for a newer car than mine 70, as mine only have 2 holes.THey make those aftermarket ones to fit many years.

 

the drivers side port is for the temp sender....jim

 

I bought a set of aluminum plugs from summit.

 

Go to any hydraulic place and you can get nice plugs of varying materials.

 

i'm trying to set up an electric fan temp switch as well..

can you tell me what type of switch you are using?

i'm guessing that 205F temp switch (along with a 190F thermostat) should suffice to keep the engine below boiling, and also keep the fans from constantly coming on, unless i hit stop & go traffic on a hot day

 

I ordered this sensor with my SPAL V2 PWM controller.
However I'm not going to be using the controller because it can't handle the
amp draw of the Taurus fans. So I'm going to relay it and sell the new controller on Ebay.

http://www.dakotadigital.com/index.c...rod/prd111.htm

I just got off the phone with Summit. I guess all 3 holes can be used for temp sensor with adaptors.

I just called Summit tech and they told me Autometer 2271 is the adaptor i need for these holes.
I think the hole is bigger then that though......calling Edelbrock now.

 

Don't set your temp switch for 205, it'll never cool off. It will always have to play catch up.

Set it at about 160 and go from there, otherwise I'll bet the temp will continue to go up if you set it at 205.

 

I use the 4 extra holes for 4 corner watering. Helps keep the engine more uniformally cool. I run 89 octane with #7 heads and 9.7:1 comp in the Florida heat, no issues

 

What's corner watering ?

I just found out the holes are 1/2" and 3/8"
Edelbrock part # 9126 and # 9127 for the plugs

 

You run hoses from the rear holes to the front holes, helps keep temps more even throughout the block and heads.

 

no i dont agree with that.. (short answer)


(long answer)
setting the fan to switch on at 160F will keep the fan running almost constantly (with a 190F stat)

ideally, you want the cooling system to remain around the stat temp, which it will while the car is moving and cooling on its own.

at a stop, or during extended idling- the coolant might retain heat and require the cooling fans to push air through the rad to further cool down the coolant.

setting the fan switch at a temp. thats between coolant boiling point, and stat opening will ensure the fans only come on to assist in reducing coolant temp.

fan should come on when coolant temp is over 205F, anmd shuts off when coolant temp drops below 205F.

thats how OEM's do it.. the fans cycle on & off to aid in extracting heat from the coolant. they are supplemental and dont run all the time.

the use of a pressurized system allows coolant to boil well over 100C (212F).

check out the chart attached.
http://www.engineeringtoolbox.com/bo...ter-d_926.html

with 9psi added pressure, water (coolant) will boil at around 238F (117C)

this is theoretically the 'overheat' point. at this point, water (coolant) vaporizes and cannot extract heat from the engine any longer.

 

Yeah I was just reading in my service manual and my temp switch for the idiot switches at approx 240F. Doesn't give you much time to react!!!

 

exactly the reason why you shouldnt use the stock temp light switch as a fan switch. by the time the switch closes the circuit to engage the relay that powers up the fan...you're boilin' over baby!

 

I think it all looks like crap Buddy............here is the solution you take the manifold off I COME PICK IT UP FOR MY CAR and you buy a nice new shiny one LMAO yea thats it that sounds like a plan yea thats it ............ LMAO

 

I wasn't aware that ~240* was the OH SH** point.
That's good to know, thanks for that info.

So I guess if I ever overheated to ~240* I should consider changing the coolant.

 

I working on the RPM intake. Can you tell me what the remaining holes are used for?