Re: Benefits of 4-port water bypass on a SBC?
Posted: Sat Dec 25, 2021 6:24 pm
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Benefits of 4-port water bypass on a SBC?
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Re: Benefits of 4-port water bypass on a SBC?
Posted: Sat Dec 25, 2021 7:23 pm
This is exactly how I understand the flow. My question is for everyone:4.The coolant flow volume that is biased to the exhaust side of the head then flows basically up and over the combustion chambers (it does not flow rear to front along the head on the exhaust side of head) where it rejoins with the smaller coolant volume coming from the holes on the intake side of the head where it does now flow along the length of head to front discharge port entering the front manifold crossover to the thermostat.
Is the water that flows from #1 & 2 cyl, the same temp, as the water that flows at #7 & 8?
Re: Benefits of 4-port water bypass on a SBC?
Posted: Sun Dec 26, 2021 1:44 am
Short answer is no on a stock configuration SBC. 7 and 8 will be hotter.Well within range of acceptable tho for what service stock engines see. It is only when the service becomes more severe or the power output is substantially increased that modifications to the flow characteristics of the cooling system will become necessary at some point. That is why I mentioned that usage needs mentioned when this topic comes up. This isn't a one answer fits all subject.
Re: Benefits of 4-port water bypass on a SBC?
Posted: Sun Dec 26, 2021 1:48 am
CJ,
The term 'large' is relative. The head gasket hole size regulates flow, with holes in the head & block usually larger. The largest holes & the greatest number of holes that transfer coolant from block to head are at the rear of the block.
The only mod that Smokey did was to plug those large core holes on the valley side of the block & then drill 0.060" steam relief holes; not sure why this was really necessary because the mating holes in the gasket are already quite small.
"We also like to plug the large core openings in the deck so that the majority of the coolant must travel to the rear of the block before it is transferred up into the cyl head."
The only other mod he does for coolant routing is the Y piece I described in an earlier post
The term 'large' is relative. The head gasket hole size regulates flow, with holes in the head & block usually larger. The largest holes & the greatest number of holes that transfer coolant from block to head are at the rear of the block.
The only mod that Smokey did was to plug those large core holes on the valley side of the block & then drill 0.060" steam relief holes; not sure why this was really necessary because the mating holes in the gasket are already quite small.
"We also like to plug the large core openings in the deck so that the majority of the coolant must travel to the rear of the block before it is transferred up into the cyl head."
The only other mod he does for coolant routing is the Y piece I described in an earlier post
Re: Benefits of 4-port water bypass on a SBC?
Posted: Sun Dec 26, 2021 1:54 am
In the second pic the front bypass hose should be one or two size bigger than the rear bypass hose. The front hose must carry the flow from both the center and rear bypass outlets to accomplish fairly equal flow in the front and rear portions of the head water jackets.
Re: Benefits of 4-port water bypass on a SBC?
Posted: Sun Dec 26, 2021 2:04 am
This is not the case with a SBC.THe rest of what Smokey said there was just nonsense. I'm sorry but some of the things we just accepted decades ago have been proven incorrect.Geoff2 wrote: ↑Sun Dec 26, 2021 1:48 am CJ,
The term 'large' is relative. The head gasket hole size regulates flow, with holes in the head & block usually larger. The largest holes & the greatest number of holes that transfer coolant from block to head are at the rear of the block.
The only mod that Smokey did was to plug those large core holes on the valley side of the block & then drill 0.060" steam relief holes; not sure why this was really necessary because the mating holes in the gasket are already quite small.
"We also like to plug the large core openings in the deck so that the majority of the coolant must travel to the rear of the block before it is transferred up into the cyl head."
The only other mod he does for coolant routing is the Y piece I described in an earlier post
Re: Benefits of 4-port water bypass on a SBC?
Posted: Sun Dec 26, 2021 2:51 am
Old smokey putting up the smoke screen again!Geoff2 wrote: ↑Sun Dec 26, 2021 1:48 am CJ,
The term 'large' is relative. The head gasket hole size regulates flow, with holes in the head & block usually larger. The largest holes & the greatest number of holes that transfer coolant from block to head are at the rear of the block.
The only mod that Smokey did was to plug those large core holes on the valley side of the block & then drill 0.060" steam relief holes; not sure why this was really necessary because the mating holes in the gasket are already quite small.
"We also like to plug the large core openings in the deck so that the majority of the coolant must travel to the rear of the block before it is transferred up into the cyl head."
The only other mod he does for coolant routing is the Y piece I described in an earlier post
Re: Benefits of 4-port water bypass on a SBC?
Posted: Sun Dec 26, 2021 11:01 am
cjperformance wrote: ↑Sun Dec 26, 2021 2:51 amOld smokey putting up the smoke screen again!Geoff2 wrote: ↑Sun Dec 26, 2021 1:48 am CJ,
The term 'large' is relative. The head gasket hole size regulates flow, with holes in the head & block usually larger. The largest holes & the greatest number of holes that transfer coolant from block to head are at the rear of the block.
The only mod that Smokey did was to plug those large core holes on the valley side of the block & then drill 0.060" steam relief holes; not sure why this was really necessary because the mating holes in the gasket are already quite small.
"We also like to plug the large core openings in the deck so that the majority of the coolant must travel to the rear of the block before it is transferred up into the cyl head."
The only other mod he does for coolant routing is the Y piece I described in an earlier post
That he did. 
Re: Benefits of 4-port water bypass on a SBC?
Posted: Sun Dec 26, 2021 4:26 pm
So why does the redirecting work if most of you say it does not?? In my situation I always have the temp reading at the head port.
Re: Benefits of 4-port water bypass on a SBC?
Posted: Mon Dec 27, 2021 1:45 am
af2,
What evidence to you have that redirecting works? If the temp sender is in the factory location, it might well read lower. Meanwhile, around the centre exh ports, temp might be 15* hotter....
What evidence to you have that redirecting works? If the temp sender is in the factory location, it might well read lower. Meanwhile, around the centre exh ports, temp might be 15* hotter....
Re: Benefits of 4-port water bypass on a SBC?
Posted: Tue Dec 28, 2021 6:38 pm
What are some thoughts when we fit sbc engines backwards
On a rake angle in a boat?
We feed water into front like normal and pull water out of rear of heads as that is the highest point
Most fit outs people put a blank plate over thermostats hole but still put temp gauge sensor next to thermostat
I would think there would be minimal flow in that area
On a rake angle in a boat?
We feed water into front like normal and pull water out of rear of heads as that is the highest point
Most fit outs people put a blank plate over thermostats hole but still put temp gauge sensor next to thermostat
I would think there would be minimal flow in that area
Re: Benefits of 4-port water bypass on a SBC?
Posted: Tue Dec 28, 2021 7:53 pm
There should be plenty of flow there even though you are pulling water out the "rear" of the manifold.It should also be the coolest place to have the sender. You would get a "better" indication of the engines true or highest coolant temperature if the sender was at the rear of engine or near the center exhaust valves if you can get it there with your heads.MELWAY wrote: ↑Tue Dec 28, 2021 6:38 pm What are some thoughts when we fit sbc engines backwards
On a rake angle in a boat?
We feed water into front like normal and pull water out of rear of heads as that is the highest point
Most fit outs people put a blank plate over thermostats hole but still put temp gauge sensor next to thermostat
I would think there would be minimal flow in that area
Re: Benefits of 4-port water bypass on a SBC?
Posted: Tue Dec 28, 2021 8:58 pm
This works fine on a parallel flow system as per SBC.MELWAY wrote: ↑Tue Dec 28, 2021 6:38 pm What are some thoughts when we fit sbc engines backwards
On a rake angle in a boat?
We feed water into front like normal and pull water out of rear of heads as that is the highest point
Most fit outs people put a blank plate over thermostats hole but still put temp gauge sensor next to thermostat
I would think there would be minimal flow in that area
Not at all great for a series flow setup as it reduces flow thru the front of the head.
Re: Benefits of 4-port water bypass on a SBC?
Posted: Tue Dec 28, 2021 9:06 pm
Please define series flow and parallel flow so we are all on the same page.
Re: Benefits of 4-port water bypass on a SBC?
Posted: Tue Dec 28, 2021 10:15 pm
Parallel is where coolant is entering the cylinder block then being metered up thru the head gasket in a uniform way, kind of divided across each cylinder, (there can/will be different sized holes typically larger on exhaust side, smaller on intake side) with minimal flow bias front to rear , then once in the head the coolant is directed out thru the thermostat. As per the small block chev.
Series is where coolant is entering the cylinder block then the largest proportion being made (bar some small transfer and steam holes along the way) to flow around every cylinder/bore and the up thru a large passage/s at the rear of the block, into the rear of the cylinder head, then forward thru the head and out thru the thermostat. As per the typical mk4 big block chev and most common early ford V8 stuff.