Discussion
Many thanks for all your replies. It's good to know that the forum's there as an invaluable source of collective knowledge!
Spoke to Real Steel who supply the CSI electric pumps, as well as Pete Master Motorsport who are running the GT Ultima. Incidently, they run two electric pumps, a send and a return and have had no problems to date. The length of the pipes compounds the problem - especially if you've insulated them like I have!
Want to avoid replacing the mechanical pump if possible and Stewart Components do an in-line 'booster' that they claim increases flow by 300%!
Sounds as if it's the way to go.
I think it will probably end up being a case of being several small solutions rather than one sure-all.
Anyway, it gives me something to write about
Thanks again all
Spoke to Real Steel who supply the CSI electric pumps, as well as Pete Master Motorsport who are running the GT Ultima. Incidently, they run two electric pumps, a send and a return and have had no problems to date. The length of the pipes compounds the problem - especially if you've insulated them like I have!
Want to avoid replacing the mechanical pump if possible and Stewart Components do an in-line 'booster' that they claim increases flow by 300%!
Sounds as if it's the way to go.
I think it will probably end up being a case of being several small solutions rather than one sure-all.
Anyway, it gives me something to write about
Thanks again all
Some interesting reading. I have found that the tick-over makes quite a difference. I have only had one case of over heating whick caused me to stop but I have had several anxious moments.
Stig - How long have you been letting the car sit there for before the temp rises to uncomfortable numbers? And in what ambient temp?
I had a problem at Le Mans last year where we sat in 25-30deg heat for nearly an hour, with the tick-over set at about 1050!
I found that fuel evaporation was a bigger problem before the car finally boiled. I had to keep re-starting after it kept stalling and I was more worried about running the battery flat, it became increasingly hard to start.
I'm hoping some water wetter will help and turning the tick-over down a tad.
How easy would an over-ride switch be to install? Any chance of a schematic of some one? I believe that having the fans cut in earlier would be a big help!
Paul
Stig - How long have you been letting the car sit there for before the temp rises to uncomfortable numbers? And in what ambient temp?
I had a problem at Le Mans last year where we sat in 25-30deg heat for nearly an hour, with the tick-over set at about 1050!
I found that fuel evaporation was a bigger problem before the car finally boiled. I had to keep re-starting after it kept stalling and I was more worried about running the battery flat, it became increasingly hard to start.
I'm hoping some water wetter will help and turning the tick-over down a tad.
How easy would an over-ride switch be to install? Any chance of a schematic of some one? I believe that having the fans cut in earlier would be a big help!
Paul
Probably not going to be well received but: cover the exhaust headers and mufflers with nomex insulation. This has been very beneficial on my other cars with over-heating problems. It is a shame to cover all that perfect stainless with nomex cloth but may necessary. Wouldn't reccomend the tape, would recommend the exhaust sleeving sold by Thermo Tec.
We had a bit of trouble on the first 7.0 liter big engine install, and found that by putting in a Miezere electric remote water pump, which pushes a tremendous amount of water through the system, the overheating issues went away. It does sound a bit like a water park ride without the engine running, and you must drill some bypass holes in your thermostat or the electric pump will blow the hose!
You can see a photo of the installation on a custom bracket at blackballed www.brammo.com site at www.brammo.com/Images/electricremotepump.jpg
We can get anyone specs of the pump if interested at cb@brammo.com
By the way, the Meziere pump is 55gallons per minute, and this was by far the highest volume single pump I could find. They have a radiator mount version as well as an 0-ringed adapters for various size hoses and fittings.
By eliminating the standard waterpump (we had gone stewart as well originally) we also made it easier to mount a cam sync pickup on the external Jesel belt drive for the sequential fuel injection setup. You can see the bypass and our fancy smancy (nice way of saying the smallest part that took the most time) cnc camsync pickup at www.brammo.com/Images/waterpumpbypass.jpg
Craig
>> Edited by brammo on Wednesday 21st May 06:21
You can see a photo of the installation on a custom bracket at blackballed www.brammo.com site at www.brammo.com/Images/electricremotepump.jpg
We can get anyone specs of the pump if interested at cb@brammo.com
By the way, the Meziere pump is 55gallons per minute, and this was by far the highest volume single pump I could find. They have a radiator mount version as well as an 0-ringed adapters for various size hoses and fittings.
By eliminating the standard waterpump (we had gone stewart as well originally) we also made it easier to mount a cam sync pickup on the external Jesel belt drive for the sequential fuel injection setup. You can see the bypass and our fancy smancy (nice way of saying the smallest part that took the most time) cnc camsync pickup at www.brammo.com/Images/waterpumpbypass.jpg
Craig
>> Edited by brammo on Wednesday 21st May 06:21
How easy would an over-ride switch be to install? Any chance of a schematic of some one? I believe that having the fans cut in earlier would be a big help!
Paul
Very easy at least with my loom - wiring already there for switch and "fan on" light (black/orange, green, black) RH side of dash. So just need a suitable switch.
ultimapaul said:
Stig - How long have you been letting the car sit there for before the temp rises to uncomfortable numbers? And in what ambient temp?
I had a problem at Le Mans last year where we sat in 25-30deg heat for nearly an hour, with the tick-over set at about 1050!
I found that fuel evaporation was a bigger problem before the car finally boiled. I had to keep re-starting after it kept stalling and I was more worried about running the battery flat, it became increasingly hard to start.
I'm hoping some water wetter will help and turning the tick-over down a tad.
How easy would an over-ride switch be to install? Any chance of a schematic of some one? I believe that having the fans cut in earlier would be a big help!
Paul
Hi mate,
The car is ticking over at about 700rpm with a smooth idle. Will richen it up a bit to make sure it's not too lean (but I'm sure it isn't because it was running mega-rich before and did the same thing)
I'd guess that it takes about 10 mins for the temp to rise to an uncomfortable level from normal operating temp which is about 82 degs.
Already have a fan override fitted. Testing has been done with fans cutting in of their own accord. Will try with fans overridden to see if I can keep it cool before it gets beyond their control. There's a wire pair in place on the loom already, just for this purpose.
Emailed Gail at AS who reckons that I already have a hi-flow pump 'none better' in his words. So leccy pump may not help (but the Stewart Components in-line booster seems like a good idea).
The search continues.....
>> Edited by Stig (moderator) on Wednesday 21st May 10:20
k wright said: Probably not going to be well received but: cover the exhaust headers and mufflers with nomex insulation. This has been very beneficial on my other cars with over-heating problems. It is a shame to cover all that perfect stainless with nomex cloth but may necessary. Wouldn't reccomend the tape, would recommend the exhaust sleeving sold by Thermo Tec.
Good point. Funnily enough I've got a good supply of the tape running along the coolant pipes ready for removal!!!
CJ
IMHO your problem is the rather large thing on top of your engine.
My advice would be to contact that guy from the US with the twin turbo set up as he must have had to deal with this problem.
I have to say (and will get hate mail for this) I agree with the factory and didn't lag my rad pipes but instead lagged the cockpit panels. It works on my car but I obviously don't have your heat exchanger, not that I wouldn't mind though.
another alternative would be to fit a bigger oil cooler with a temp sensor. The factory demo car has(had?) a larger one fitted but they covered half of it because quote "it was too efficient and was running to cold".
Worth a thought.
Andy
IMHO your problem is the rather large thing on top of your engine.
My advice would be to contact that guy from the US with the twin turbo set up as he must have had to deal with this problem.
I have to say (and will get hate mail for this) I agree with the factory and didn't lag my rad pipes but instead lagged the cockpit panels. It works on my car but I obviously don't have your heat exchanger
, not that I wouldn't mind though. another alternative would be to fit a bigger oil cooler with a temp sensor. The factory demo car has(had?) a larger one fitted but they covered half of it because quote "it was too efficient and was running to cold".
Worth a thought.
Andy
Stig said: The car is ticking over at about 700rpm with a smooth idle.
Ordinary mechanical water pumps are very speed sensitive and pump almost no water at low RPM. If your engine is overheating in traffic you may find it helps (or at least delays the inevitable) if you raise the revs to 1500 rpm or so. In conventional systems this also reduces the pressure in the top hose so postpones any boil-over.
ultimaandy said: CJ
IMHO your problem is the rather large thing on top of your engine.
My advice would be to contact that guy from the US with the twin turbo set up as he must have had to deal with this problem.
I have to say (and will get hate mail for this) I agree with the factory and didn't lag my rad pipes but instead lagged the cockpit panels. It works on my car but I obviously don't have your heat exchanger
another alternative would be to fit a bigger oil cooler with a temp sensor. The factory demo car has(had?) a larger one fitted but they covered half of it because quote "it was too efficient and was running to cold".
Worth a thought.
Andy
LOL! Don't worry, hindsight is a wonderful thing and I did go a bit mad with the insulation thing. Still, it was in reaction to owners bemoaning high cockpit temps. so it's six of one and half a dozen of the other. Boil the occupants or boil the engine
I have also got insulation on the cockpit panels, luggage bins and heater pipes so I think I'm pretty well covered!
However, whilst the pipes will radiate a couple of degrees. What then? There's no airflow through the sidepods (especially when stationery or in slow traffic) so once the ambient temperature goes up in the sidepods, I wouldn't have thought they'd help much?
Anyway, I'm going to try a few things out and see where that gets me before resorting to more drastic measures.
GreenV8S said:
Stig said: The car is ticking over at about 700rpm with a smooth idle.
Ordinary mechanical water pumps are very speed sensitive and pump almost no water at low RPM. If your engine is overheating in traffic you may find it helps (or at least delays the inevitable) if you raise the revs to 1500 rpm or so. In conventional systems this also reduces the pressure in the top hose so postpones any boil-over.
Pete,
The engine has a high-flow pump fitted but I agree about the low rpm efficiency. I tried raising the revs, but it was a law of diminishing returns as the ratio of heat generated by the engine vs. heat dissapated stayed about the same.
The nett result was that the temperature crept up again.
Am angling towards fitting a secondary electric pump on the rad inlet which is switchable with my fan override switch. This should help maintain a decent flow rate (20-80 litres per min) and help create turbulence in the rad.
As an alternative water pump device, we have had others use the Davies Craig unit, which is lightweight and easily slipped in line and even has a controller.
The irony of many of the aftermarket waterpumps like the the Stewart is that they are designed for more RPMS of race engines, rather than slow speed idle cooling. Though AS has the best their is, that will not solve your issue of moving water at idle to the exchanger in any quanity to let the electric fan do its work.
The irony of many of the aftermarket waterpumps like the the Stewart is that they are designed for more RPMS of race engines, rather than slow speed idle cooling. Though AS has the best their is, that will not solve your issue of moving water at idle to the exchanger in any quanity to let the electric fan do its work.
Stig said:I tried raising the revs, but it was a law of diminishing returns as the ratio of heat generated by the engine vs. heat dissapated stayed about the same.
In theory that shouldn't be the case - the heat output only varies a little bit with revs and a bit more with torque, while the water flow varies very dramatically at low revs. Might suggest that low water flow rate is not your problem and you need more air, or colder air, going through the radiator. Is all the air going through the rad cold fresh air, or is there any possibility of air recirculation when stationary?
brammo said: As an alternative water pump device, we have had others use the Davies Craig unit, which is lightweight and easily slipped in line and even has a controller.
The irony of many of the aftermarket waterpumps like the the Stewart is that they are designed for more RPMS of race engines, rather than slow speed idle cooling. Though AS has the best their is, that will not solve your issue of moving water at idle to the exchanger in any quanity to let the electric fan do its work.
Came to the same conclusion Craig and have gone ahead and ordered the Davies Craig EWP.
Will run this in series with the existing pump and it will come on with my fan override switch (as well as anytime the fans are running).
In addition (because I always err on the side of caution!), I added an 8" Profan for the oil cooler. I may run this from a seperate switch, but it should aid the engine idle temp, as well as drawing fresh air (slightly warmed through the oil cooler) into the engine bay.
Fingers crossed!
GreenV8S said:
Stig said:I tried raising the revs, but it was a law of diminishing returns as the ratio of heat generated by the engine vs. heat dissapated stayed about the same.
In theory that shouldn't be the case - the heat output only varies a little bit with revs and a bit more with torque, while the water flow varies very dramatically at low revs. Might suggest that low water flow rate is not your problem and you need more air, or colder air, going through the radiator. Is all the air going through the rad cold fresh air, or is there any possibility of air recirculation when stationary?
Well, obviously theory and practical application don't always agree!
The air is drawn through the rad with two fans which account for about 90% of the total radiator surface area.
The air is drawn from the front scoop and deflected up and over the bonnet. Recirculation in that environment was very unlikely. As I mentioned before, I was actually surprised at how warm (ie not hot) the air was.
The radiator itself is fully ducted and was drawing air from inside the workshop on a reasonably cool day.
Put it this way, it wasn't nearly as hot as being stuck in traffic in the centre of France!
Stig,
Would love to see some photos of the DC motor install and hope that does it. Fan on the oil cooler is probably a good idea anyway. There are oil thermostats that will kick on only when the oil temp on the engine side reaches the appropriate temperature, as you dont want the car engine to warm up too slowly! Mocal and a few other have units and have a simple wiring to turn on and off the fan.
Can point you to a part if needed.
Craig
Would love to see some photos of the DC motor install and hope that does it. Fan on the oil cooler is probably a good idea anyway. There are oil thermostats that will kick on only when the oil temp on the engine side reaches the appropriate temperature, as you dont want the car engine to warm up too slowly! Mocal and a few other have units and have a simple wiring to turn on and off the fan.
Can point you to a part if needed.
Craig
brammo said: Stig,
Would love to see some photos of the DC motor install and hope that does it. Fan on the oil cooler is probably a good idea anyway. There are oil thermostats that will kick on only when the oil temp on the engine side reaches the appropriate temperature, as you dont want the car engine to warm up too slowly! Mocal and a few other have units and have a simple wiring to turn on and off the fan.
Can point you to a part if needed.
Craig
Thanks Craig,
As I mentioned, I'm only going to run the oil cooler manually as oil temp has been fine when the car is on the move.
The EWP mod will be covered in gory detail on the website. I swear I'm only getting these issues as motivation to keep updating it
Brammbo,
I know you have LS1/LS6 experience relative to these Ultima Cars. Both the LS1 and the LS6 have a PCM/ECM module. Have you found a good way to use the Primary Control Module, or the Engine Control Module (not sure which between the LS1 and LS6) to control the Thermostat AND Fans?
I'm wondering if there was any way to programmatically use the Vette PCM's/ECM's with the "In-Line" H20 Cooler that you mentioned above?
Would be very nice! And, no need for manual switches - if it could be done. I'm not an electronics expert, so the matter is a bit above my head.
For example:
Begin Code
IF Coolant Temp => 210F, THEN StartFanFunction,
IF Coolant Temp => 210F, AND Engine Idle is =< "X" RPM, THEN StartFanFunction + StartInLineCoolerFunction
etc., etc., etc.
End Code (the actual temp numbers are irrelevant. The "Procedure" is the issue at hand)
Not that the PCM code source is Visual Basic, or C++, but I'm sure you get my thought process on this one.
Could the Procedural Functions with the PCM?/ECM? be used in this way to control these NON-GM-Corvette external devices, controls, switches, etc.?
Thanks,
L2Pilot
I know you have LS1/LS6 experience relative to these Ultima Cars. Both the LS1 and the LS6 have a PCM/ECM module. Have you found a good way to use the Primary Control Module, or the Engine Control Module (not sure which between the LS1 and LS6) to control the Thermostat AND Fans?
I'm wondering if there was any way to programmatically use the Vette PCM's/ECM's with the "In-Line" H20 Cooler that you mentioned above?
Would be very nice! And, no need for manual switches - if it could be done. I'm not an electronics expert, so the matter is a bit above my head.
For example:
Begin Code
IF Coolant Temp => 210F, THEN StartFanFunction,
IF Coolant Temp => 210F, AND Engine Idle is =< "X" RPM, THEN StartFanFunction + StartInLineCoolerFunction
etc., etc., etc.
End Code (the actual temp numbers are irrelevant. The "Procedure" is the issue at hand)
Not that the PCM code source is Visual Basic, or C++, but I'm sure you get my thought process on this one.
Could the Procedural Functions with the PCM?/ECM? be used in this way to control these NON-GM-Corvette external devices, controls, switches, etc.?
Thanks,
L2Pilot
The Davis Craig pump is what i fitted and it's cheapest at Real Steal, was only £90 2years ago. Ripspeed wanted £130 at the time.
I fitted it down by the radiator and had it on a switch as well, the controler they try and sell you does not work very well for our V8's so don't be tempted as it's a waste of money.
Have fun...
I fitted it down by the radiator and had it on a switch as well, the controler they try and sell you does not work very well for our V8's so don't be tempted as it's a waste of money.
Have fun...
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