Ls1 coolant tubes
I don't know...Have you? The same can be asked for both scenarios. The research is not there to say definitive for either side and just seeing how they come from the factory explains enough. The 320hp LS1 had them...The 405hp Z06 did not...hmmmm
GM put the rear steam ports in what..5 years and only in the early LS1 Corvette and F-body? Now here we are...11+ year later, LS engines in Corvette (505hp 7.0), GTO, F-body, CTSV, Trucks, SUVs and NONE....Nadda have factory equipped rear steam ports...
GM must have determined, they were not necessary.
We should do a poll....I would bet you would see a very high percentage of the folks here have the rear ports blocked off and no issues...
GM put the rear steam ports in what..5 years and only in the early LS1 Corvette and F-body? Now here we are...11+ year later, LS engines in Corvette (505hp 7.0), GTO, F-body, CTSV, Trucks, SUVs and NONE....Nadda have factory equipped rear steam ports...
GM must have determined, they were not necessary.
We should do a poll....I would bet you would see a very high percentage of the folks here have the rear ports blocked off and no issues...
Based on these conclusions, I will personally vent the rear on any LSX I modify. If I ever buy another LS1 and do absolutely nothing to it, I will personally not worry about the rear steam ports.
Lemme toss a question out here:
Forget whether or not GM used four corner, two corner or no corner coolant ports.
Don't you think that it's a good idea to add a little help to the heads by increasing how the coolant can flow out from the ends of the heads?
The cooler the heads can be kept, the better they perform. The LT1 engine had reverse cooling-it went to the heads first. And it worked.
Forget whether or not GM used four corner, two corner or no corner coolant ports.
Don't you think that it's a good idea to add a little help to the heads by increasing how the coolant can flow out from the ends of the heads?
The cooler the heads can be kept, the better they perform. The LT1 engine had reverse cooling-it went to the heads first. And it worked.
The general consensus among those arguing that coolant flow through the back ports is not a bad thing is that GM determined they were not necessary... on the back... on stock motors. Power adder cars experience ring land failures predominantly in cylinder 7, not cylinder 1. Those venting four corners don't tend to have issues that can be traced back to steam venting.
Based on these conclusions, I will personally vent the rear on any LSX I modify. If I ever buy another LS1 and do absolutely nothing to it, I will personally not worry about the rear steam ports.
Exactly. My argument is it may not help on a bolt-on or H/C/I car, but what will it hurt? If you don't believe these ports flow coolant, put a valve on a tee to atmosphere on a line back to the front of your motor. Heat up the motor and open the valve to a jar. Just remember to wear gloves and eye protection
Based on these conclusions, I will personally vent the rear on any LSX I modify. If I ever buy another LS1 and do absolutely nothing to it, I will personally not worry about the rear steam ports.
Exactly. My argument is it may not help on a bolt-on or H/C/I car, but what will it hurt? If you don't believe these ports flow coolant, put a valve on a tee to atmosphere on a line back to the front of your motor. Heat up the motor and open the valve to a jar. Just remember to wear gloves and eye protection
Not sure we are going to come to a consensus here, but why are you so insistent on blocking ports that pass cooling fluid through them?
Staging Lane
Joined: Aug 2013
Posts: 51
Likes: 0
From: California
There are more reasons then blocking off steam ports to make the ring lands crack. If you are running a factory fuel rail, then the fuel going to cylinders 7 and 8 get the hottest fuel. Hot fuel = hot cylinder temps. Both those cylinders are located at the back of the engine...where all the heat collects. All the heat from the front of the engine gets pushed back while driving. So just in general, the back two cylinders will always be hotter. There is more to it then the steam ports! BTW I have nothing against running steam ports
Heres Mine....
some adapters that go to 1/8 NPT, some brake line, and a distribution block...
goes up to the front and hits the return on the radiator...
I'm not against having some sort of steam port system, I'm just saying I wouldn't jump to the conclusion that without them, the engine is doomed.
There are more reasons then blocking off steam ports to make the ring lands crack. If you are running a factory fuel rail, then the fuel going to cylinders 7 and 8 get the hottest fuel. Hot fuel = hot cylinder temps. Both those cylinders are located at the back of the engine...where all the heat collects. All the heat from the front of the engine gets pushed back while driving. So just in general, the back two cylinders will always be hotter. There is more to it then the steam ports! BTW I have nothing against running steam ports
Either way, additional coolant flow on the back two steam ports is not a bad thing. If you knew two cylinders were going to be hotter for whatever reason, wouldn't you want to pass more coolant there rather than potentially trapping steam pockets?
Basically, you're saying if the tune is spot on, there will be no issues? I agree with that. I have not seen any issues with my combo and I even hot lap at the track. I have a completely full bolt-On H/C/I LS1...
I'm not against having some sort of steam port system, I'm just saying I wouldn't jump to the conclusion that without them, the engine is doomed.
I'm not against having some sort of steam port system, I'm just saying I wouldn't jump to the conclusion that without them, the engine is doomed.
Kind of like the fact that I will keep my Oil Level sensor even though it gets in the way of starter removal and I check my oil regularly. It may not save my #7 ring land, but I'll certainly let you know if I ever fail that ring land while I'm spraying with the port vented.
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Verdad Gallardo Another one here. 500+hp, 6800 RPM shifts and the back ports are blocked off. This is an urban legend...From the research I have done, the #7 failures are not from a hot cylinder, but a lean condition and more prominent on Nitrous applications. The rear cylinders are the last to get air and suffer from detonation.
Like mentioned, they are blocked off on the LS7 and no issues there....
The attached above where the rears connected is no different than having them blocked
Like mentioned, they are blocked off on the LS7 and no issues there....
The attached above where the rears connected is no different than having them blocked
it has been a proven fact that steam gets trapped back there because of how things sit in the car and the water jacket routing....
you wont pop a motor from going lean on nitrous....you will burn a valve though, and that on its own can cause a lot of other damage
almost all nitrous damage come from detonation or an extremely rich condition and auto ignition from being too hot
nitrous on its own is not flammable....takes combustion to break apart the molecules to release the oxygen.
no fuel = no combustion = no nitrous break down
typically its the lean condition that create detonation...not the nitrous destroying stuff...
I ran a 350 shot on 13.1:1 AFR...all day long
read my plugs... had to use a #10 plug and pulled 12* on my motor.
you have also said something contradictory... back cylinders are the last to get air so they are the leanest.???
no... back cyllinders on stock style intakes get too much air because of the Ram effect because our intakes are contradictory to how air wants to flow
which does create a leaner condition....lean doesnt directly create knock... but lean creates heat, which creates knock...
also, Naturally Aspirated....engines usually dont have issues with those 2 cylinders...but start to add power adders that change how you have to tune the vehicle, and its easy to get into trouble fast.
its a very bad idea to block off those steam vents...
and its why plenty of people offer a kit you can buy...
if it wasnt needed, the kit would not exist.
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
+1 on steam pocket formation (steam forms even when you don't intend it to).
Also, if you have any air leak into the cooling system, the air will end up in the heads with nowhere to go.
Better safe than marginal or worse.
Also, if you have any air leak into the cooling system, the air will end up in the heads with nowhere to go.
Better safe than marginal or worse.
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
Last edited by joecar; Oct 23, 2013 at 11:15 AM. Reason: corrected RHS vs LHS
Launching!
Joined: May 2010
Posts: 274
Likes: 1
Here's what I'm doing with my steam ports this time around... The rear crossover tube is from a cadillac, GM part #12605716. The front cross over tube is from the ls6. I dont have any finished pics but I'm using the black braided fuel hose and have the 2 lines connected together with a stainless 1/4" Y fitting where it plumbs into the radiator.
Here's the rear cadillac crossover...
Here in the green square is the front ls6 crossover...
Here's the rear cadillac crossover...
Here in the green square is the front ls6 crossover...
Staging Lane
Joined: Mar 2014
Posts: 95
Likes: 0
Okay. Ive been running my car (383 ci, ported heads/cam blah blah) for a while w/o rsp. Oh yeah, it's a street car huffing a 200 shot also. The general reason for the vent tubs is simply to expel steam from the heads to keep coolant flow at a "safe rate". Now we all know that when we first start upgrading one of the first things that we do is headers, cooler spark plugs(TR6/5.5), 160 therm. With that being said, heat has nothing to do with it. Our heads cool exceptionally well because they're made of what? Aluminum. No heat issues here.
Staging Lane
Joined: Mar 2014
Posts: 95
Likes: 0
Okay. Ive been running my car (383 ci, ported heads/cam blah blah) for a while w/o rsp. Oh yeah, it's a street car huffing a 200 shot also. The general reason for the vent tubs is simply to expel steam from the heads to keep coolant flow at a "safe rate". Now we all know that when we first start upgrading one of the first things that we do is headers, cooler spark plugs(TR6/5.5), 160 therm. With that being said, heat has nothing to do with it. Our heads cool exceptionally well because they're made of what? Aluminum. No heat issues here.
Okay. Ive been running my car (383 ci, ported heads/cam blah blah) for a while w/o rsp. Oh yeah, it's a street car huffing a 200 shot also. The general reason for the vent tubs is simply to expel steam from the heads to keep coolant flow at a "safe rate". Now we all know that when we first start upgrading one of the first things that we do is headers, cooler spark plugs(TR6/5.5), 160 therm. With that being said, heat has nothing to do with it. Our heads cool exceptionally well because they're made of what? Aluminum. No heat issues here.
Okay. Ive been running my car (383 ci, ported heads/cam blah blah) for a while w/o rsp. Oh yeah, it's a street car huffing a 200 shot also. The general reason for the vent tubs is simply to expel steam from the heads to keep coolant flow at a "safe rate". Now we all know that when we first start upgrading one of the first things that we do is headers, cooler spark plugs(TR6/5.5), 160 therm. With that being said, heat has nothing to do with it. Our heads cool exceptionally well because they're made of what? Aluminum. No heat issues here.