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St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
None of the race cars used thermostats on them. A few of our customer cars that we have done that are track cars only are done in a similar fashion but it is more than just not running the thermostat on the pump.
Your oem system with blocked bypass and no thermostat will cool better than just adding a larger aftermarket radiator.
Am I reading this correctly? Are you saying that, in order to provide better cooling, a bigger radiator isn't necessary? Blocking the bypass and removing thermostat will provide the best cooling solution? Or do you mean these mods in addition to the better core radiator will render best cooling?
If that's true, are there any associated risks? Is this only recommended for dedicated track cars and not suggested for daily drivers?
Last edited by BigMonkey73; 07-12-2016 at 06:08 PM.
Am I reading this correctly? Are you saying that, in order to provide better cooling, a bigger radiator isn't necessary? Blocking the bypass and removing thermostat will provide the best cooling solution? Or do you mean these mods in addition to the better core radiator will render best cooling?
If that's true, are there any associated risks? Is this only recommended for dedicated track cars and not suggested for daily drivers?
I am saying blocking the bypass on LS3/LS7 water pump will help but especially doing so on the Evans LS pump may improve cooling enough to not need the additional capacity of a dual row radiator. It depends on horsepower (BTU's produced), ambient temps and airflow through your radiator. This is recommended for those that track their car for 20-30 minute sessions on roadcourses. Adding cooling capacity with dual row radiator is always a plus. I said dual row, not dual pass. A dual pass radiator will decrease coolant flow and may have an adverse effect. Race cars with dual pass radiators are an engineered system with matching components.
There's a lot more to cooling than I can talk about. David Wright is a cooling engineer and Technical Sales Manager for Evans Cooling Systems, almost everything I posted I learned from him during a lengthy conversation over the phone.
The Evans LS1/LS6 high flow racing pump & pulley flyer attached below.
Experience the Evans advantage with Evans LS series products. Evans LS series pumps and pulleys are available as well as high flow thermostats. The pumps have been designed to increase flow 20% more than the OEM style replacement pumps, and maintains equal flow to both cylinder banks at any engine RPM. Evans improved design includes an engineered impeller, a billet pulley hub, heavy duty roller bearing and ceramic shaft seal. The 8-vane scrolled impeller design reduces parasitic horsepower loss at high engine RPM. Evans has also applied this technology to the GEN III truck pump.
Evans small pulley is designed to work with the OEM crank pulley. This pulley design maximizes cooling capacity by increasing coolant flow on factory applications more effectively than stock pulley combinations. Evans large pulley increases performance when using an under-drive crank pulley. Evans small and large pulleys are blower belt compatible. Optimal pump RPM range is 2500 - 6500. Pump flow (gpm) is maximized at 5500 pump RPM. For sustained high engine RPM applications our suggested combination is Evans large pulley and a 25% under-drive crank pulley. The pulleys are anodized hard coated aluminum. Refer to LSI Pump RPM vs. Engine RPM chart (pg. 2) to compare pulley drive ratios.
Evans small pulley is designed to work with the OEM crank pulley. This pulley design maximizes cooling capacity by increasing coolant flow on factory applications more effectively than stock pulley combinations. Evans large pulley increases performance when using an under-drive crank pulley. Evans small and large pulleys are blower belt compatible. Optimal pump RPM range is 2500 - 6500. Pump flow (gpm) is maximized at 5500 pump RPM. For sustained high engine RPM applications our suggested combination is Evans large pulley and a 25% under-drive crank pulley. The pulleys are anodized hard coated aluminum. Refer to LSI Pump RPM vs. Engine RPM chart (pg. 2) to compare pulley drive ratios.
Evans also recommends the use of their modified thermostats, available in 160°F and 180°F temperature settings. The modified thermostat increases coolant flow by more than 50% over other after market thermostats. The increased coolant flow maximizes the cooling advantage of the Evans LS series pumps. Evans LSI thermostats can also be used on all OEM LSI pumps.
Pump, pulley and thermostat are assembled prior to shipping. Thermostats may be purchased separately.
Contact time is important both to absorb heat, and to dissipate heat.
Move your hand quickly over a bar-b-q then try it slower and slower...
You'll easily see the difference
That's got to be the dumbest analogy I have ever heard. Q(dot)=m(dot) x c x delta t.
If you don't understand that equation or why that analogy is bogus, then frankly, you aren't qualified to speak on the subject no matter how many racers you talk too.
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
I could be wrong, and you may want to check your rules but I don't know if you can run Evans coolant in some of the race series. Most of the time they want straight water in the car in case of an accident you are not dealing with a chemical spill....other than maybe oil.
I'll probably order a pump when I rebuild my motor sometime this winter.
Before that, is there any trick to blocking off the bypass other than capping the lines? I already have my heater core removed, I just took the line that normally runs to it and fed it back into the return line on the heater core loop.
Before that, is there any trick to blocking off the bypass other than capping the lines? I already have my heater core removed, I just took the line that normally runs to it and fed it back into the return line on the heater core loop.
what method did you use to fill the system then? I'm trying to find stuff that does not fail ever. For example you still have to cap the reservoir bottom. Any clever ways to do that with a bullet proof cap?
what method did you use to fill the system then? I'm trying to find stuff that does not fail ever. For example you still have to cap the reservoir bottom. Any clever ways to do that with a bullet proof cap?
Maybe I didn't explain what I did well enough.
There are two lines that run to the heater core from the "block" where the pump bypass is. I removed one of those lines completely, then cut the other and looped it around to where the one I removed would normally attach. Essentially all I did was remove the heater core from the loop. No other changes were made.
I don't have any pics of it on my computer, but since I was flushing my cooling system at the time anyways, this was a five minute mod to essentially eliminate the heater core from the loop.
I'll probably order a pump when I rebuild my motor sometime this winter.
Before that, is there any trick to blocking off the bypass other than capping the lines? I already have my heater core removed, I just took the line that normally runs to it and fed it back into the return line on the heater core loop.
Evans closes off the bypass passage inside the pump behind the t-stat housing. This eliminates hot water from the block from mixing with the cooled fluid returning to pump from radiator. You don't have to mess with the heater lines unless you want 100% block off for dedicated track use.
I ran with no stat on my race car with a large radiator for a season and the motor took to long to warm up. even with a pre heated sump tank.
As a result the oil was getting fuel diluted dropping viscosity level (lab analysis) from running cold too long and had to be changed out to often when the oil qualities were otherwise fine.
You could try to tune the rich idle out but be aware of this most engines (especially more loose race builds) will contaminate oil quickly running cold.
I use a stat now and my oil is still good at twice the run time.
My interest isn't no-tstat, its more fully blocking the bypass. Some tstats have holes in the block-off plate and some may not expand completely or precisely... I'd like to know its completely blocked.
Ok, just to get clarification.....if you run a water pump with a plugged bypass (like the Evans unit listed above), is there any downfall or issues if driving the car on the street? Does the heater and everything else function normal? I live in a non freezing climate, but winters do require a heater on colder mornings.
I want to keep the tstat since the car is a street cruiser, but I'd like more cooling for road course use. I have an external oil cooler and stock radiator with heat extraction hood. Running as hard as I could on Hoosiers at Thunderhill last Sunday (about 85 degree temps) I was hitting 230 degrees water and 265 degrees oil. Car ran perfect with no obvious signs of getting hot.
My next addition was going to be a high capacity radiator but if I can get by with plugged bypass water pump, that might be an easier way to go.
If someone has a water pump laying around, how about opening the tstat in pot then setting it in pump and take pic... curious how well it covers the bypass. If it does a good job then not really an issue.
The LPE tstat has goofy holes in the block off plate... not all do though.
Ok, just to get clarification.....if you run a water pump with a plugged bypass (like the Evans unit listed above), is there any downfall or issues if driving the car on the street? Does the heater and everything else function normal? I live in a non freezing climate, but winters do require a heater on colder mornings.
It takes longer to heat up to operating temps but no deal breaker and yes everything functions as normal.
Originally Posted by TrackAire
I want to keep the tstat since the car is a street cruiser, but I'd like more cooling for road course use. I have an external oil cooler and stock radiator with heat extraction hood. Running as hard as I could on Hoosiers at Thunderhill last Sunday (about 85 degree temps) I was hitting 230 degrees water and 265 degrees oil. Car ran perfect with no obvious signs of getting hot.
If your oil cooler is mounted directly in front of radiator I'd mount it on front bumper support directly behind screened area on C5Z for better air path and flow-through while unblocking your main radiator from that obstruction. Oil cooler in front of radiator is not only an obstruction that slows down flow-through of air...it also pre-heats the air that flows through radiator thus decreasing your in/out delta of coolant. Your oil temps will lower and your engine coolant temps will be lower as well.
It takes longer to heat up to operating temps but no deal breaker and yes everything functions as normal.
If your oil cooler is mounted directly in front of radiator I'd mount it on front bumper support directly behind screened area on C5Z for better air path and flow-through while unblocking your main radiator from that obstruction. Oil cooler in front of radiator is not only an obstruction that slows down flow-through of air...it also pre-heats the air that flows through radiator thus decreasing your in/out delta of coolant. Your oil temps will lower and your engine coolant temps will be lower as well.
Thanks for the input, just saw your reply today....somehow I missed it. Regarding the oil cooler, do you mean mount it behind one of the narrow openings on each side of the license plate area or cut out the license plate area and mount behind that opening?
Regarding the plugged bypass, what do you estimate my coolant temp drop would be if I installed a plugged bypass waterpump with my current set up listed above?
07-11-2016, 06:30 PM
