Converting LS1 heads to reverse flow cooling....
#21
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reverse flow is not something evans has invented , Gm engineers invented it back in the 1950's on the real Pontiac motors ( called "gushers" ) they worked great back then but due to machining costs and the way they supplied the water it wasn't economical to produce ( it had a tube in the head the aimed the water flow towards the exaust side first and was prone to rusting out ) , we restorers replace this pipe with a stainless one, I think the matter of reverting back to a block first to head flow was a matter of costs in production and warentee problems not patent infringement also the pump and pump cover location could have some bearing in flow too , when you start pushing water around corners it effects the amount of flow the pump can push before it cavitates .
#22
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reverse flow is not something evans has invented , Gm engineers invented it back in the 1950's on the real Pontiac motors ( called "gushers" ) they worked great back then but due to machining costs and the way they supplied the water it wasn't economical to produce ( it had a tube in the head the aimed the water flow towards the exaust side first and was prone to rusting out ) , we restorers replace this pipe with a stainless one, I think the matter of reverting back to a block first to head flow was a matter of costs in production and warentee problems not patent infringement also the pump and pump cover location could have some bearing in flow too , when you start pushing water around corners it effects the amount of flow the pump can push before it cavitates .
#23
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I spoke with the VP of Evans about reverse cooling the LS engines a couple of weeks ago. Evans is working with Meziere on a reverse cooling electric water pump for these engines. Evans will be coming out with a mechanical pump kit in the future.
Evans holds the patent on reverse flow cooling and after some twenty years won their court battle with GM just before it turned into Government Motors.
Steve
Evans holds the patent on reverse flow cooling and after some twenty years won their court battle with GM just before it turned into Government Motors.
Steve
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
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Jay Fisher (08-03-2019)
#28
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The Meziere electric pump setup can be purchased now. They are still working on a mechanical pump that will fit without having to move the alternator.
You can use one Meziere electric pump for both banks but this will work much better if you use one pump per bank. Moroso has adapters to make this work. You should be able to get these from Meziere to get -12 lines to the heads and out the block to the radiator and from the radiator back to the pumps.
Evans had Cometic make reworked head gaskets to improve coolant flow at the back of the block. These you can order from Evans. These gaskets will help cool the rear cylinders on both standard and reverse flow applications.
The early heads had four corner vapor line positions and a spider going to all four corners of the heads. This was done away with on some of the later heads. LS7 heads have the drillings for the four corner setup but they use only the front holes. It is important to use the rear holes as well so you should use the early four corner vapor lines according to Evans.
I should have some photos in a week or two.
Steve
You can use one Meziere electric pump for both banks but this will work much better if you use one pump per bank. Moroso has adapters to make this work. You should be able to get these from Meziere to get -12 lines to the heads and out the block to the radiator and from the radiator back to the pumps.
Evans had Cometic make reworked head gaskets to improve coolant flow at the back of the block. These you can order from Evans. These gaskets will help cool the rear cylinders on both standard and reverse flow applications.
The early heads had four corner vapor line positions and a spider going to all four corners of the heads. This was done away with on some of the later heads. LS7 heads have the drillings for the four corner setup but they use only the front holes. It is important to use the rear holes as well so you should use the early four corner vapor lines according to Evans.
I should have some photos in a week or two.
Steve
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
#30
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Great thread . . .
I have ordered the Meziere WP419 Mechanical billet pump and Kurt's water vapour System.
I will have to talk to Evans after ready this thread.
Keep up the good work !
I have ordered the Meziere WP419 Mechanical billet pump and Kurt's water vapour System.
I will have to talk to Evans after ready this thread.
Keep up the good work !
#31
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If you have any questions regarding reverse cooling, call Dave at Evans Cooling 888-990-2665
My contact, Steve the former VP at Evans, is no longer there. I won't be getting any more updates unfortunately.
Steve
My contact, Steve the former VP at Evans, is no longer there. I won't be getting any more updates unfortunately.
Steve
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
#32
#34
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Meziere has or can get the pieces required to make a reverse cooling setup using one or preferably two of their electric pumps. It will be a while before a mechanical pump kit is available. There are some clearance issues to work out with the mechanical pump installation.
Evans Cooling is under new ownership. My friend Steve formerly Evans VP and Jack Evans will be back in business with products in the next few months.
Steve
Evans Cooling is under new ownership. My friend Steve formerly Evans VP and Jack Evans will be back in business with products in the next few months.
Steve
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
#35
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Not so dumb really... GM was sued for reverse flow cooling design. I believe it was Evans who patented this design and GM did not have an agreement to incorporate it into the LT1. Last I heard the lawsuit was still pending. My guess is GM stopped using it because their lawyers told them they were going to lose the case. Lick your wounds and walk away.
What makes you think you can steal a design and get away with it especially on such a large scale? Don't you think it would have been easier to contract with Evans to use their design, pay them their royalties, and be done?
read this...http://money.cnn.com/magazines/fsb/f...3431/index.htm
What makes you think you can steal a design and get away with it especially on such a large scale? Don't you think it would have been easier to contract with Evans to use their design, pay them their royalties, and be done?
read this...http://money.cnn.com/magazines/fsb/f...3431/index.htm
#36
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Actually Evans won the suit just before GM went belly up. They got paid $$$.
Now, Dupont took over the company (they had a considerable interest in the company) and decided they just want to sell coolant and not bother with pumps, radiators and other products. They fired Jack Evans the founder and Steve Pressley the VP.
Evans Engineering is still owned by Jack Evans and my friend Steve Pressley. Plan is for them to continue with the coolant pumps and other products. Probably be a few months before they are up and running.
Steve
Now, Dupont took over the company (they had a considerable interest in the company) and decided they just want to sell coolant and not bother with pumps, radiators and other products. They fired Jack Evans the founder and Steve Pressley the VP.
Evans Engineering is still owned by Jack Evans and my friend Steve Pressley. Plan is for them to continue with the coolant pumps and other products. Probably be a few months before they are up and running.
Steve
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
#37
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I researched some postings but there doesn't seem to be as much info on this as I was hoping. I was hoping if someone could corroborate, elaborate, or discredit the following: (sorry it is long and multiple related postings)
"Guys,
If you look at the coolant flow through an LS series block, it doesn't appear to be very difficult at all to convert. I do
know that it has been done and I will be converting Darton sleeved 427 when it goes back into my SS. FWIW, I always drill
and tap the front and rear coolant bleed holes on any max effort deal I do. I run -6 lines from all four corners of the
heads to the top of the radidator in the stock location. This was suggested to me by Kurt Urban a couple of years ago.
Since that time, I have successfully run 12:1 and above with 93 octane pump gas (with good chambers...) I do this mod on
all nitrous and F/I builds and some NA builds if the owner is up for it.
Getting back to the reverse cooling issue, taking a quick look at the passages in the block and head, if we feed the top
hole on the block first and make the lower hole the return, I see no issues with bleeding the system since the fatory
coolant bleed holes are the highest point in the cooling system (assuming an F-Body setup.) This would be a simple setup
using an external WP with Meziere's AN adapters.
I may not be 100% correct in all my assumptions but I am confident enough that I will be doing this on my own build.
Shane
************************************
I posted this on the 944 Hybrids forum where I'm documenting the build....
"I am only looking to do a mod to the LS water pump and remove the thermostat. On the last V8 swap I did to a 2.8l S-10,
all I did was remove the T-stat and did not change to a larger radiator. All my overheating issues went away. In the
winter, I just reinstalled the T-stat and the heater blew nice n hot and engine never overheated. My theory is the stock
Porsche 944 NA radiator with the T-stat removed would be the best cooling set-up and obviously the easiest. The inner port
hole between the heater ports on the LS1 pump can be blocked off. I have read elswhere that a 1/2" hole is drilled in a
freeze plug and installed. I also see that the 160deg T-stats have 4 small holes drilled in that block-off plate. The only
reason I can see why GM put that small rear block-off plate(spring loaded) was in case the radiator (even heater core) were
to be clogged, the coolant would just recirculate within the block. Looking at the Truck Pump, the inner port hole could be
enirely blocked off with an epoxy'ed freeze plug or the stock T-stat could simply have the upper piston drilled/removed and
the heater would function normally and the water velocity would remain constant and increase with RPMs".
"I removed the back cover from the truck WP to double check the flow route of this pump which should be exactly the same as
all the LS pump routings. From what I see, if that inner port hole is blocked off completely and the T-stat removed the
coolant velocity would be higher going to the top radiator and cool much better"
Looking at the truck pump veins, I don't see why the serpentine/pully can't just be reversed and the same mod done to the
port hole and the water would flow backwards for head to block cooling (reverse).
**************************************
I am new to the LS world a short time ago I was mistakenly under the impression that like the LT engines the LS were
"reverse cooled". Several years ago I ran some Evans Cooling products in a Ford engine with very good results. Since at
that time I wasn't working on any GM stuff I got the full story when talking to the Evans guys.
Anyway when we set out to build our first LSX Block Nitrous engine I made a slight mistake. The engine would use a remote
water pump so we welded AN bungs to the motor plate. The mistake that I made on the initial engine is that I reverse cooled
it by hooking the water lines up backwards. That engine (in that configuration) made the most horsepower that we ever had.
We never had a problem with cooling or steam. This was a drag race engine with little time to heat up.
Since my error was pointed out we have run the lines the proper way. One of the things on my list to check on the dyno is
to do back to back pulls with the lines hooked up both ways.
I should be able to get back to the dyno in about a month and will give it a try at that time.
I had some conversations with a thermal engineer regarding the flow through the engine. The gentleman that I discussed this
is very in the know and currently works in the business. The mapping and probing that is done on water flow models is
unreal. He felt that I got lucky because of the short run times. He felt that the gasket restrictions would need to be
studied to provide the correct amount of coolant for enough time to absorb heat from the heads and block.
Hopefully I can try it again and let you guys know what I find.
Robin
********************************
One problem with the small block Chevy, and now I believe the LS*, is that with both heads flowing into a single port, then
into a hose back to the rad, each head does not flow at the same time. This was something Smokey Yunick investigated. What
happens is that as the coolant heats up and begins to flow, one side(head) will heat up faster ie. hotter, with more
pressure. This greater pressure makes only the hotter side flow because of the greater pressure. Then, as the hotter side
flows, it cools down enough, aqs the non flowing side heats up. There is then a transition of flow. In the end what happens
is an alternating flow, resulting in an inefficient system, and hotter heads, and less compression.
What "Smokey" did was drill holes into the ends of the heads edging towards the exhuast side ( hottest ) . Tapped and
installed piped fittings with hoses and a Y juction to a main rad return hose. This allowed the heads to flow more
effiently(from the front of head) and to flow simultaneously, resulting in more stable head temps.
It would seem that the LS1 heads are ready made for this mod, with the casting plugs in the exact optimum area.
"Smokey Yunick" for those that don't know was yester years David Vizard in the racing/performance genre. He has many
patents including the extended tip spark plugs we all enjoy. When I read something of his, I take it as gospel. Though some
new technology and metalurgy has changed from his days. He tried to get GM to use a reverse flow setup for many years.
Your thoughts are appreciated...
Art
"Guys,
If you look at the coolant flow through an LS series block, it doesn't appear to be very difficult at all to convert. I do
know that it has been done and I will be converting Darton sleeved 427 when it goes back into my SS. FWIW, I always drill
and tap the front and rear coolant bleed holes on any max effort deal I do. I run -6 lines from all four corners of the
heads to the top of the radidator in the stock location. This was suggested to me by Kurt Urban a couple of years ago.
Since that time, I have successfully run 12:1 and above with 93 octane pump gas (with good chambers...) I do this mod on
all nitrous and F/I builds and some NA builds if the owner is up for it.
Getting back to the reverse cooling issue, taking a quick look at the passages in the block and head, if we feed the top
hole on the block first and make the lower hole the return, I see no issues with bleeding the system since the fatory
coolant bleed holes are the highest point in the cooling system (assuming an F-Body setup.) This would be a simple setup
using an external WP with Meziere's AN adapters.
I may not be 100% correct in all my assumptions but I am confident enough that I will be doing this on my own build.
Shane
************************************
I posted this on the 944 Hybrids forum where I'm documenting the build....
"I am only looking to do a mod to the LS water pump and remove the thermostat. On the last V8 swap I did to a 2.8l S-10,
all I did was remove the T-stat and did not change to a larger radiator. All my overheating issues went away. In the
winter, I just reinstalled the T-stat and the heater blew nice n hot and engine never overheated. My theory is the stock
Porsche 944 NA radiator with the T-stat removed would be the best cooling set-up and obviously the easiest. The inner port
hole between the heater ports on the LS1 pump can be blocked off. I have read elswhere that a 1/2" hole is drilled in a
freeze plug and installed. I also see that the 160deg T-stats have 4 small holes drilled in that block-off plate. The only
reason I can see why GM put that small rear block-off plate(spring loaded) was in case the radiator (even heater core) were
to be clogged, the coolant would just recirculate within the block. Looking at the Truck Pump, the inner port hole could be
enirely blocked off with an epoxy'ed freeze plug or the stock T-stat could simply have the upper piston drilled/removed and
the heater would function normally and the water velocity would remain constant and increase with RPMs".
"I removed the back cover from the truck WP to double check the flow route of this pump which should be exactly the same as
all the LS pump routings. From what I see, if that inner port hole is blocked off completely and the T-stat removed the
coolant velocity would be higher going to the top radiator and cool much better"
Looking at the truck pump veins, I don't see why the serpentine/pully can't just be reversed and the same mod done to the
port hole and the water would flow backwards for head to block cooling (reverse).
**************************************
I am new to the LS world a short time ago I was mistakenly under the impression that like the LT engines the LS were
"reverse cooled". Several years ago I ran some Evans Cooling products in a Ford engine with very good results. Since at
that time I wasn't working on any GM stuff I got the full story when talking to the Evans guys.
Anyway when we set out to build our first LSX Block Nitrous engine I made a slight mistake. The engine would use a remote
water pump so we welded AN bungs to the motor plate. The mistake that I made on the initial engine is that I reverse cooled
it by hooking the water lines up backwards. That engine (in that configuration) made the most horsepower that we ever had.
We never had a problem with cooling or steam. This was a drag race engine with little time to heat up.
Since my error was pointed out we have run the lines the proper way. One of the things on my list to check on the dyno is
to do back to back pulls with the lines hooked up both ways.
I should be able to get back to the dyno in about a month and will give it a try at that time.
I had some conversations with a thermal engineer regarding the flow through the engine. The gentleman that I discussed this
is very in the know and currently works in the business. The mapping and probing that is done on water flow models is
unreal. He felt that I got lucky because of the short run times. He felt that the gasket restrictions would need to be
studied to provide the correct amount of coolant for enough time to absorb heat from the heads and block.
Hopefully I can try it again and let you guys know what I find.
Robin
********************************
One problem with the small block Chevy, and now I believe the LS*, is that with both heads flowing into a single port, then
into a hose back to the rad, each head does not flow at the same time. This was something Smokey Yunick investigated. What
happens is that as the coolant heats up and begins to flow, one side(head) will heat up faster ie. hotter, with more
pressure. This greater pressure makes only the hotter side flow because of the greater pressure. Then, as the hotter side
flows, it cools down enough, aqs the non flowing side heats up. There is then a transition of flow. In the end what happens
is an alternating flow, resulting in an inefficient system, and hotter heads, and less compression.
What "Smokey" did was drill holes into the ends of the heads edging towards the exhuast side ( hottest ) . Tapped and
installed piped fittings with hoses and a Y juction to a main rad return hose. This allowed the heads to flow more
effiently(from the front of head) and to flow simultaneously, resulting in more stable head temps.
It would seem that the LS1 heads are ready made for this mod, with the casting plugs in the exact optimum area.
"Smokey Yunick" for those that don't know was yester years David Vizard in the racing/performance genre. He has many
patents including the extended tip spark plugs we all enjoy. When I read something of his, I take it as gospel. Though some
new technology and metalurgy has changed from his days. He tried to get GM to use a reverse flow setup for many years.
Your thoughts are appreciated...
Art
#38
TECH Senior Member
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You're replying to an 8-year old post, the author of which has not been here for the last 5 years.
#40