Cooling my solid roller 496
Melting Slicks
Joined: Aug 2006
Posts: 3,429
Likes: 20
From: Kingston Ontario
Originally Posted by L79racer
Change the water pump. You say that when you rev it up it puts out too much pressure. Well if its putting out that much pressure its probably flowing the water too fast threw the radiator at higher rpms and not letting the water cool
OR
quote
If You have the stage IV It won't work on the street. It doesn't really flow any water below 4000 rpm It is intended to run from 4500 - 8000 rpm
plus and BB rad is usually about 28" can to can, I hope your new rad helps. Also, maybe ...I know you said your timing was checked but what if your balancer markings aren't right?
Change the water pump. You say that when you rev it up it puts out too much pressure. Well if its putting out that much pressure its probably flowing the water too fast threw the radiator at higher rpms and not letting the water cool
OR
quote
If You have the stage IV It won't work on the street. It doesn't really flow any water below 4000 rpm It is intended to run from 4500 - 8000 rpm
plus and BB rad is usually about 28" can to can, I hope your new rad helps. Also, maybe ...I know you said your timing was checked but what if your balancer markings aren't right?
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Originally Posted by L79racer
Change the water pump. You say that when you rev it up it puts out too much pressure. Well if its putting out that much pressure its probably flowing the water too fast threw the radiator at higher rpms and not letting the water cool
OR
quote
If You have the stage IV It won't work on the street. It doesn't really flow any water below 4000 rpm It is intended to run from 4500 - 8000 rpm
plus and BB rad is usually about 28" can to can, I hope your new rad helps. Also, maybe ...I know you said your timing was checked but what if your balancer markings aren't right?
Change the water pump. You say that when you rev it up it puts out too much pressure. Well if its putting out that much pressure its probably flowing the water too fast threw the radiator at higher rpms and not letting the water cool
OR
quote
If You have the stage IV It won't work on the street. It doesn't really flow any water below 4000 rpm It is intended to run from 4500 - 8000 rpm
plus and BB rad is usually about 28" can to can, I hope your new rad helps. Also, maybe ...I know you said your timing was checked but what if your balancer markings aren't right?
I set the engine at top dead center and installed MSD balancer tape to verify the timing.
Neal
Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
I've tried using one of the speedway TruCool aluminum radiators (universal fit) and it just will not do the job.
I have it sealed up to the core support and have 3 electric fans on it, a Mark VIII pulling and 2-12" fans on the front of the radiator pushing. I installed a rather large engine oil cooler, a stage III Stewart pump, a high flow stat from Stewart and have tried just about every timing setting I could but the temps don’t respond to any thing. I installed a radiator cap fitting on above the T-Stat so I could get all the air out of the system, the only issue with this is the pump will put up enough pressure to lift a 24lb cap ( when I blip the throttle) expelling a good bit of water to the overflow bottle. When I purchased the Stewart pump they told me not to install a cap at the T-Stat for this reason. I can only guess that the radiator flow capability is not sufficient and is causing this issue.
The temp stays around 180 while cruising around town or idling but once I get up to highway speeds it will very slowly start climbing, it will level out around 220* to 230* than once I slow down the temp will slowly come back down. The inlet temp and outlet temp of the radiator will equal each other while running down the highway so in my mind this indicates that the radiator is dissipating all the heat it can. I have removed the headlights and gave that a try to see if it may be air flow but the temps were the same.
I have verified the inlet temp and outlet temp of the radiator with an IR gun so I’m pretty sure these temps are correct.
I’ve read quite a few threads on cooling here and have decided to go with the Dewitt radiator along with the twin Spals.
I’ve looked into the BeCool radiators, the modular set-ups they offer, but it looks like the only difference is the fans, the radiator is the same in the kits. The only thing I had a question on was the insert that they install in the tubs for turbulent flow (not sure if this will make a difference).
One thing is for sure, I will test the capacity of the Dewitt radiator and fans once installed.
I’ll report back and let everyone know how it comes out, radiator and fans should ship in a day or so.
The cost for the BeCool set-up and the Dewitt set-up are just about the same so I went with Tom due to his support of the vette hobby.
Neal
I have it sealed up to the core support and have 3 electric fans on it, a Mark VIII pulling and 2-12" fans on the front of the radiator pushing. I installed a rather large engine oil cooler, a stage III Stewart pump, a high flow stat from Stewart and have tried just about every timing setting I could but the temps don’t respond to any thing. I installed a radiator cap fitting on above the T-Stat so I could get all the air out of the system, the only issue with this is the pump will put up enough pressure to lift a 24lb cap ( when I blip the throttle) expelling a good bit of water to the overflow bottle. When I purchased the Stewart pump they told me not to install a cap at the T-Stat for this reason. I can only guess that the radiator flow capability is not sufficient and is causing this issue.
The temp stays around 180 while cruising around town or idling but once I get up to highway speeds it will very slowly start climbing, it will level out around 220* to 230* than once I slow down the temp will slowly come back down. The inlet temp and outlet temp of the radiator will equal each other while running down the highway so in my mind this indicates that the radiator is dissipating all the heat it can. I have removed the headlights and gave that a try to see if it may be air flow but the temps were the same.
I have verified the inlet temp and outlet temp of the radiator with an IR gun so I’m pretty sure these temps are correct.
I’ve read quite a few threads on cooling here and have decided to go with the Dewitt radiator along with the twin Spals.
I’ve looked into the BeCool radiators, the modular set-ups they offer, but it looks like the only difference is the fans, the radiator is the same in the kits. The only thing I had a question on was the insert that they install in the tubs for turbulent flow (not sure if this will make a difference).
One thing is for sure, I will test the capacity of the Dewitt radiator and fans once installed.
I’ll report back and let everyone know how it comes out, radiator and fans should ship in a day or so.
The cost for the BeCool set-up and the Dewitt set-up are just about the same so I went with Tom due to his support of the vette hobby.
Neal
Give us an update, ok ?
Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
Originally Posted by L79racer
Change the water pump. You say that when you rev it up it puts out too much pressure. Well if its putting out that much pressure its probably flowing the water too fast threw the radiator at higher rpms and not letting the water cool
OR
quote
If You have the stage IV It won't work on the street. It doesn't really flow any water below 4000 rpm It is intended to run from 4500 - 8000 rpm
plus and BB rad is usually about 28" can to can, I hope your new rad helps. Also, maybe ...I know you said your timing was checked but what if your balancer markings aren't right?
Change the water pump. You say that when you rev it up it puts out too much pressure. Well if its putting out that much pressure its probably flowing the water too fast threw the radiator at higher rpms and not letting the water cool
OR
quote
If You have the stage IV It won't work on the street. It doesn't really flow any water below 4000 rpm It is intended to run from 4500 - 8000 rpm
plus and BB rad is usually about 28" can to can, I hope your new rad helps. Also, maybe ...I know you said your timing was checked but what if your balancer markings aren't right?
overheats.
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
When you get on the highway and start getting up there in water temp, pop open your headlights and see if the temp starts to go down. If it does, then you know you need to get more air to the radiator .If it makes no difference, then do a very thorough clean and flush of the cooling system draining it thru the block drains. Also, run your motor up to 3,000 rpms while parked, and see if the lower radiator hose is collapsing on you. Make sure your radiator/condensor is sealed up real good around the sides and top . Run 80% water to 20% coolant with a bottle of Water Wetter . Check your engine timing and see if its retarded. Check belt for slippage. Are your Cats plugged up ? If all else fails....take out the engine thermostat and drill 2 : 1/8" holes in the metal flange to allow any air to escape from the motor . If all else really fails....leave the thermostat out till you get a better handle on the problem --- the water will come up to temp. soon enough.
Give us an update, ok ?
Give us an update, ok ?
I am in the middle of the new Dewitts radiator install right now, one thing I have noticed is the view through the radiator is better on Toms radiator, on the Tru-Kool it is hard to see through it, more fins and tubes than Toms. This alone may help with air flow.
The lower hose is 3 pices with brass splices along with the internal spring, I've checked a couple times to make sure the lower hose was not restricting the flow.
When I pulled the Tru-Kool out today I looked at the internals to see if I could see any gunk but it looked clean on both the inlet and outlet.
Radiator is sealed tight to the core support, I was running just that mostly water with some coolent and water wetter. No cats, side pipes with spiral baffles. I've played with timing and it made no change on the cooling no matter were I put it, so I put back to were it runs the best. The T-stat is a high flow Stewart with the holes drilled.
I should have the new radiator installed today, may be soon enough to take a drive tonight.
Neal
Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
Im sorry but i was in error ; I have a stage 3 Stewart Pump. I have a Dewitts BB radiator with twin fans in shroud from an early 1990's LT1 Vette . They move a ton of air and both come on at the same time (200 f. on / 180 f. off) . I find if im going at least 35 mph in 3rd gear and the outside temp is no higher than 80 f. , the fans never come on. I run straight distilled water with one bottle of Water Wetter . Dave.
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Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Im sorry but i was in error ; I have a stage 3 Stewart Pump. I have a Dewitts BB radiator with twin fans in shroud from an early 1990's LT1 Vette . They move a ton of air and both come on at the same time (200 f. on / 180 f. off) . I find if im going at least 35 mph in 3rd gear and the outside temp is no higher than 80 f. , the fans never come on. I run straight distilled water with one bottle of Water Wetter . Dave.
Neal
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Neal
Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
I'm still working on the lower hose, I've been able to piece one together but don't trust it enough to drive it on the road.
I let it sit and idle for about 10 minutes or so and for the first time since I've had the 496 in the car the fans will cycle. I am using the Spal controller and have been for a while, it has worked great for me. The first fan comes on and slowly speeds up until it gets to full speed and than the other fan will come on but just for a minute, the temps come down and the second fan shuts off, the second fan may run for a minute or so before shutting down. It’s late in the afternoon now but it’s still 86* here even with the sun down.
What do yawl think on the fans, would it make a difference on which fan I have on first, the one on the inlet side or the outlet side of the radiator. I'm gona swap them around and see, right now I have the one on the outlet side of the radiator coming on first.
The real test will be driving on the road but I can say this looks promising.
I started with both fans on full speed and let it idle, the outlet side of the radiator would not get above 120*, than I shut the override off and let the controller do its thing. The fans shut off till the temps got to 160* on the outlet of the radiator than the first fan came on. After idling for a while the first fan went to high speed and the second fan came on at high speed for a short time, the temp on the outlet of the radiator came up to about 175*, and then back to about 160* than the second fan shut off and the first fan slowed down a little. Once the second fan shut off I let it idle for a while longer and the second fan did not come back on.
Soon as I can sort the lower hose out I will give an update on the road test.
Thank everyone for the help so far
Neal
I let it sit and idle for about 10 minutes or so and for the first time since I've had the 496 in the car the fans will cycle. I am using the Spal controller and have been for a while, it has worked great for me. The first fan comes on and slowly speeds up until it gets to full speed and than the other fan will come on but just for a minute, the temps come down and the second fan shuts off, the second fan may run for a minute or so before shutting down. It’s late in the afternoon now but it’s still 86* here even with the sun down.
What do yawl think on the fans, would it make a difference on which fan I have on first, the one on the inlet side or the outlet side of the radiator. I'm gona swap them around and see, right now I have the one on the outlet side of the radiator coming on first.
The real test will be driving on the road but I can say this looks promising.
I started with both fans on full speed and let it idle, the outlet side of the radiator would not get above 120*, than I shut the override off and let the controller do its thing. The fans shut off till the temps got to 160* on the outlet of the radiator than the first fan came on. After idling for a while the first fan went to high speed and the second fan came on at high speed for a short time, the temp on the outlet of the radiator came up to about 175*, and then back to about 160* than the second fan shut off and the first fan slowed down a little. Once the second fan shut off I let it idle for a while longer and the second fan did not come back on.
Soon as I can sort the lower hose out I will give an update on the road test.
Thank everyone for the help so far
Neal
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
One other thing
Before when I would blip the throttle after warming up the hose form the T-stat to the radiator would swell a little now the hose will shrink some, it apears Toms radiator may flow a little better then the
Tru-Kool.
Still early to tell but promising.
Neal
Before when I would blip the throttle after warming up the hose form the T-stat to the radiator would swell a little now the hose will shrink some, it apears Toms radiator may flow a little better then the
Tru-Kool.
Still early to tell but promising.
Neal
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Car idling in the sun in gear with one fan running at less than full speed, temp rock solid at 180*. Turn both fans on and temp will drop below 160* on the outlet of the radiator.
Installed the lower hose today late, should be able to test drive tomorrow.
Neal
Installed the lower hose today late, should be able to test drive tomorrow.
Neal
Pro
Joined: Nov 2007
Posts: 710
Likes: 0
From: Northern Florida
Sounding good ; give her a good run . Let us know.
Drifting
Joined: Jun 2002
Posts: 1,620
Likes: 7
From: Orlando Florida
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
After getting the lower hose on and taking it for a drive on the hwy it still does the same thing. Temps climb when at 3000 to 3500rpms, temps will get to about 220 to 230*. I was running a high flow T-stat and after thinking about what some were saying here I found a 180* T-stat with a 1" opining and tried it. It did appear to hold the temps down to around 210 to 220* which in my opinion is still to high. I'm thinking of trying some restrictor plates to see if going even smaller will help.
Anyone have any ideas on what could be the issue with the engine that may be causing so much heat?
Cruising at 3000 rpms is only 60 mph, the engine shouldn't be making much over 100 HP at this load but the heat it’s producing seems to be allot, so much so the cooling system can't handle it.
My next step may be to remove the hood and see how it does cruising without it.
I was able to find the flow numbers for the stage IV pump, at 1500 rpms its flowing 34 gpm, at 2000-47 gpm, at 2500-55 gpm, at 3000-69 gpm, and at 3500-81 gpm.
These numbers were not hugely different form the stage I pump, those numbers being 1500-32 gpm, 2000-42 gpm, 2500-55 gpm, 3000-65 gpm and at 3500-77 gpm
I'm going to try restricting the water flow more and then possibly replace the pump with a normal flow pump and give that a try.
noonie mentioned cavitation at the pump so replacing the pump with a standard pump should indicate if this was the issue.
Thanks for all the help so far from everyone; I'll keep chipping away at it till I get this figured out hopefully. Some times it’s frustrating
I do have better control of the temps at lower rpms now.
Neal
Anyone have any ideas on what could be the issue with the engine that may be causing so much heat?
Cruising at 3000 rpms is only 60 mph, the engine shouldn't be making much over 100 HP at this load but the heat it’s producing seems to be allot, so much so the cooling system can't handle it.
My next step may be to remove the hood and see how it does cruising without it.
I was able to find the flow numbers for the stage IV pump, at 1500 rpms its flowing 34 gpm, at 2000-47 gpm, at 2500-55 gpm, at 3000-69 gpm, and at 3500-81 gpm.
These numbers were not hugely different form the stage I pump, those numbers being 1500-32 gpm, 2000-42 gpm, 2500-55 gpm, 3000-65 gpm and at 3500-77 gpm
I'm going to try restricting the water flow more and then possibly replace the pump with a normal flow pump and give that a try.
noonie mentioned cavitation at the pump so replacing the pump with a standard pump should indicate if this was the issue.
Thanks for all the help so far from everyone; I'll keep chipping away at it till I get this figured out hopefully. Some times it’s frustrating
I do have better control of the temps at lower rpms now.
Neal