To block off, or not to block off, water ports at back of heads
03-04-2019, 02:05 AM
#1
Rennlist Member
Thread Starter
To block off, or not to block off, water ports at back of heads
S4 engine in a track car so no heater core.
Typically driver side head has the rear water port blocked, and the passenger side has a spigot that feeds into the heater core.
So, should I block off the passenger side or, put a spigot on the driver side and bridge the rear of the heads?
Mostly just curious if the heater core circuit is necessary and should be retained in some fashion or if it can be completely deleted.
Typically driver side head has the rear water port blocked, and the passenger side has a spigot that feeds into the heater core.
So, should I block off the passenger side or, put a spigot on the driver side and bridge the rear of the heads?
Mostly just curious if the heater core circuit is necessary and should be retained in some fashion or if it can be completely deleted.
03-04-2019, 04:14 AM
#2
Rennlist Member
You can delete it without any detriments. You won't be able to connect the heater core, but as you said, you don't need it.
Only thing is is that the hard line that connects the other heater core hose to the rest of the coolant circuit under the coolant reservoir needs to be capped.
Only thing is is that the hard line that connects the other heater core hose to the rest of the coolant circuit under the coolant reservoir needs to be capped.
03-04-2019, 09:55 AM
#3
The head gaskets force the coolant in theory to pass through the rear ports of the heads. So if you cap the passenger side it will be just like the driver side. I'm wondering how the flow from front to rear is affected when the gaskets are shot.
03-04-2019, 11:45 AM
#4
Rainman
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...wonder what'd be the outcome if you had an open port on both heads with a "balance tube" between them?
in case coolant pressure (different than rad cap pressure) is different on 1 side of the block than the other.
in case coolant pressure (different than rad cap pressure) is different on 1 side of the block than the other.
03-04-2019, 01:17 PM
#5
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Basic Site Sponsor
Basic Site Sponsor
Some of the 944 people are adamant that air gets trapped in the back cylinder and back of the head. Lindsey Racing makes and promotes a kit to bleed off this air.
In terms of water flow, a 928 engine and a 944 engine are identical...so if it occurs on a 944 engine it is going to occur on a 928 engine.
It may only be a function of some other factors (bad head gaskets), but in almost all of the 928 engines I take apart, which don't have catastrophic damage, cylinder #8 always has the highest piston to wall clearance.
In your situation, I've been venting the back of both heads, with small lines, to the reservior.
It's cheap and easy insurance, with zero downside.
In terms of water flow, a 928 engine and a 944 engine are identical...so if it occurs on a 944 engine it is going to occur on a 928 engine.
It may only be a function of some other factors (bad head gaskets), but in almost all of the 928 engines I take apart, which don't have catastrophic damage, cylinder #8 always has the highest piston to wall clearance.
In your situation, I've been venting the back of both heads, with small lines, to the reservior.
It's cheap and easy insurance, with zero downside.
03-04-2019, 01:38 PM
#6
Three Wheelin'
Hey Adam, lateral question.
Sounds like you are getting some serious weight off the car.
What do you think the curb weight will be when you hit your goal?
Dave.
Sounds like you are getting some serious weight off the car.
What do you think the curb weight will be when you hit your goal?
Dave.
03-04-2019, 04:30 PM
#7
Archive Gatekeeper
Rennlist Member
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Hi Adam-
Here's a quick video of the bleeders Greg references, on the back of the Zombie motors back in 2013. The rubber hose out the top ran back to the reservoir.
https://www.youtube.com/watch?v=odJr...ature=youtu.be
Here's a quick video of the bleeders Greg references, on the back of the Zombie motors back in 2013. The rubber hose out the top ran back to the reservoir.
https://www.youtube.com/watch?v=odJr...ature=youtu.be
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03-04-2019, 05:55 PM
#8
Rennlist Member
You can delete it without any detriments. You won't be able to connect the heater core, but as you said, you don't need it.
Only thing is is that the hard line that connects the other heater core hose to the rest of the coolant circuit under the coolant reservoir needs to be capped.
Only thing is is that the hard line that connects the other heater core hose to the rest of the coolant circuit under the coolant reservoir needs to be capped.
Many have wondered about that choice...
I wont mention rain races, its both obvious AND I dont think youre that hardcore into racing you'd do it..but if you would, youre _going_ to need warm air.
