751 (edited by darkostoj 2019-09-10 07:37 AM)

Re: I bought a Rolls Royce and want to build it.

rlchv70 wrote:
TheEngineer wrote:

So if you pump water through the radiator too fast, it doesn't cool down as much, and then you start to counter your heat removal capacity gain from increased volumetric flow with the decrease that comes from using hotter water. Heat transfer relies on temperature differential after-all. So it's more complicated than saying "the more water you can push the better", because as with most things, there are trade offs.

Some cars do fine with no thermostat, because the radiator is over-sized and the increase in flow rate doesn't really lead to a coolant temp increase that hinders things. Some cars cannot run without a thermostat because it breaks the balance of the system and leads to a thermal runaway. There is no magic one line answer that solves all setups.

Former cooling system engineer here.

Remember that it is a system.  You pump the water through the radiator faster, it doesn't cool off as much in the radiator, but it also doesn't heat up as much going through the engine.  The net difference is that the coolant runs cooler, all things being equal. Q=m * Cp * delta T

Problem is, things aren't equal.  The main problem is pressure.  Without a thermostat, the pressure in the upper hose and radiator are increased.  This can exceed their design pressure and leading to failures.

Increasing the flow rate may lead to hot spots in the engine and radiator, also causing unexpected failures.

Best practice is to keep a functioning thermostat.  Will let the engine warm up quickly and maintain its temp.

I was hoping you could shed some light on how to design a proper cooling system from scratch?

My assumptions are that we use pressure at the radiator inlet & radiator outlet to determine the flow rate correct?

*Assuming we have no thermostat* we can use things like changing water pump flow, thermostat housing restrictor plate, single/double/triple pass radiator to change the flow characteristics.

So if we plumb a pressure gauge at the radiator inlet, and another at the radiator output we can determine the amount of restriction right?

Do you have a step by step process on how to accurately size/design a radiator cooling system from scratch?


-----------------------------------------------

Other updates on the car

1. removed the AEM ecu and went to a factory computer.  Runs much better, much simpler, and using the OEM engine harness.

2. Currently trying to figure out how to pull CAN/Serial data off the OEM ecu to power my dash gauge display.  It's not a super easy thing since the car is PRE-08 so the CAN system isn't standard. Also the ECU doesn't have oil pressure, temp, or fuel level.

3.  Going to add hood vents to help extract some engine heat

4. Adding an accusump

5. Going to add a oil/water exchanger for the oil cooler and remove the air cooler in front of the radiator.

6. Going to dig into the radiator/cooling system on how to cool better.

----------------------------------------------

We are racing the car at the Empire Hill Climb in Michigan this Saturday.

https://empirechamber.com/event/empire- … b-revival/

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award

Re: I bought a Rolls Royce and want to build it.

darkostoj wrote:

I was hoping you could shed some light on how to design a proper cooling system from scratch?

My assumptions are that we use pressure at the radiator inlet & radiator outlet to determine the flow rate correct?

*Assuming we have no thermostat* we can use things like changing water pump flow, thermostat housing restrictor plate, single/double/triple pass radiator to change the flow characteristics.

So if we plumb a pressure gauge at the radiator inlet, and another at the radiator output we can determine the amount of restriction right?

Do you have a step by step process on how to accurately size/design a radiator cooling system from scratch?

That is a very loaded question with a complicated answer.  The way the OEMs do it correctly is based on experience, CFD, wind tunnel testing, road testing, and a bunch of iterations.


For our purposes, you stuff as much radiator in the car as possible.  Make sure as much air can pass through the radiator as possible and will not recirculate.  Utilize OEM thermostat and water pump.  Plumb the radiator to the engine with short, but not restrictive piping.  Make sure the suction side will not collapse (use hard pipe or hoses with springs inside).  Since we do not do a lot of low speed driving, one electric fan is usually enough to keep it cool when pitting.

To answer your questions regarding measuring restriction and flow rate:

Flow rate is a function of both the pressure drop and the restriction.  To measure the restriction, you would need to know both the flow rate and pressure drop, to measure the flow rate, you need to know the restriction and pressure drop, and so on.  The equations can get complicated and really doesn't gain you a lot of information for our purposes.

As long as you have a thermostat, you don't need to know any of this.  Oversize the radiator and the thermostat will control the flow rate to maintain the proper temperature.

Re: I bought a Rolls Royce and want to build it.

Concur with the above. Biggest radiator you can fit, ducted well so all the air from the front of the car goes through it, not around it, and can then escape the engine bay somehow. Simplify the routing to be just the short loop in and out plus the bypass loop for when the thermostat is closed. Factory style 180°F or lower thermostat. It was discussed earlier that the viper thermostat is a strange 3 position one, but you said you already took care of simplifying that.

Other things you can consider, put in an oil temp gauge. If the oil is getting too hot get a bigger cooler, it will help.

And check tuning, can't recall if you have an AFR gauge already. If the ECU is slow to richen the mixture you'll generate more heat. Been battling that in the saab, stupid thing was sticking in the 14s even as boost built, which makes temps skyrocket. Since you went back to the stock computer that may change things for better or worse.

20+ Time Loser FutilityMotorsport
Turbo Dodge Powered E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: I bought a Rolls Royce and want to build it.

Our Ford V8 Jegs radiator is way more that we need but it's nice to have to add tape to the grill on the cold days and not have to give it a second thought on hot days. I don't think the car has seen over 190 all year.

Of course we have 8 cylinders less than you.

Apocalyptic Racing - Occupy Pit Lane racing
Racing the "Toylet" Toyota Celica powered by Chevrolet Ecotec.
24x Loser with the Celica. 16x loser in other fine machines
Overall winner Gingerman 2019

755

Re: I bought a Rolls Royce and want to build it.

Brett85p wrote:

Our Ford V8 Jegs radiator is way more that we need but it's nice to have to add tape to the grill on the cold days and not have to give it a second thought on hot days. I don't think the car has seen over 190 all year.

Of course we have 8 cylinders less than you.

So you guys are running that new 2-cylinder Ecotec? wink

Captain
Team Super Westerfield Bros.
'93 Acura Integra - No VTEC Yo!

Re: I bought a Rolls Royce and want to build it.

VKZ24 wrote:
Brett85p wrote:

Our Ford V8 Jegs radiator is way more that we need but it's nice to have to add tape to the grill on the cold days and not have to give it a second thought on hot days. I don't think the car has seen over 190 all year.

Of course we have 8 cylinders less than you.

So you guys are running that new 2-cylinder Ecotec? wink

I hope I didn't just jinx us....make that 6 cylinders less....

Apocalyptic Racing - Occupy Pit Lane racing
Racing the "Toylet" Toyota Celica powered by Chevrolet Ecotec.
24x Loser with the Celica. 16x loser in other fine machines
Overall winner Gingerman 2019

757 (edited by darkostoj 2019-09-11 03:18 PM)

Re: I bought a Rolls Royce and want to build it.

Unfortunately, a thermostat is not possible due to the space constraints right now.  I need to 3d model a new thermostat housing to have it fit, since anything OEM won't work.

So, right now...without a thermostat the car has a triple pass radiator.

It's obvious to "fit the largest radiator possible."  What about single/double/triple pass?  Any ideas on how to select which is best?

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award

758

Re: I bought a Rolls Royce and want to build it.

what about an inline thermostat housing?
https://www.amazon.com/Meziere-WN0071-I … B003NDFEC0

Re: I bought a Rolls Royce and want to build it.

Caveat, I am not a radiator expert. In theory the more passes, the better. However the more passes the better your water pump needs to be. The more passes the higher the restriction of the radiator since you're trying to push the water through less cross sectional area, but a longer distance. So if the water pump isn't up to the job, a triple pass might work worse than a single or double.

20+ Time Loser FutilityMotorsport
Turbo Dodge Powered E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: I bought a Rolls Royce and want to build it.

Spank wrote:

what about an inline thermostat housing?
https://www.amazon.com/Meziere-WN0071-I … B003NDFEC0

Use this or make your own.

The Engineer is correct, generally, the more radiator passes, the more efficient, but has a greater restriction, heavier, and maybe thicker.

761 (edited by darkostoj 2019-09-12 07:04 AM)

Re: I bought a Rolls Royce and want to build it.

rlchv70 wrote:
Spank wrote:

what about an inline thermostat housing?
https://www.amazon.com/Meziere-WN0071-I … B003NDFEC0

Use this or make your own.

The Engineer is correct, generally, the more radiator passes, the more efficient, but has a greater restriction, heavier, and maybe thicker.

I don't think i'll be able to fit an inline housing....however I got to thinking and I may try mounting a thermostat housing on the radiator and not the engine.

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award

Re: I bought a Rolls Royce and want to build it.

darkostoj wrote:
rlchv70 wrote:
Spank wrote:

what about an inline thermostat housing?
https://www.amazon.com/Meziere-WN0071-I … B003NDFEC0

Use this or make your own.

The Engineer is correct, generally, the more radiator passes, the more efficient, but has a greater restriction, heavier, and maybe thicker.

I don't think i'll be able to fit an inline housing....however I got to thinking and I may try mounting a thermostat housing on the radiator and not the engine.

You better make sure there is a decent size hole to bypass some coolant through a rad mounted thermostat or it may never get its initial signal to open.

Are you actually worried this will run too cool?!? I see a racecar thermostat as a cheap absolutely unnecessary device that can randomly fail and blow up my expensive bits. (this has happened to me) (we race in the hot south)

Homestead Chump 5th-Sebring 6th-PBIR Lemons 9th - Charlotte Chump  CrashnBurn 9th
Sebring 6th again -NOLA Chump 1st -PBIR Chump Trans Fail 16th
Daytona 11th - Sebring 6th - Atlanta Motor Speedway 2nd - Road Atlanta Trans Fail 61st-Road Atlanta 5th
Daytona 13th - Charlotte 9th - Sebring 2nd-Charlotte 25th broken brakes - Road Atlanta 14 10th-Daytona 14  58th- Humid TT 19th Judges' Choice!

Re: I bought a Rolls Royce and want to build it.

Team Infinniti wrote:
darkostoj wrote:
rlchv70 wrote:

Use this or make your own.

The Engineer is correct, generally, the more radiator passes, the more efficient, but has a greater restriction, heavier, and maybe thicker.

I don't think i'll be able to fit an inline housing....however I got to thinking and I may try mounting a thermostat housing on the radiator and not the engine.

You better make sure there is a decent size hole to bypass some coolant through a rad mounted thermostat or it may never get its initial signal to open.

Are you actually worried this will run too cool?!? I see a racecar thermostat as a cheap absolutely unnecessary device that can randomly fail and blow up my expensive bits. (this has happened to me) (we race in the hot south)

I have been struggling with keeping the car cool.

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award

Re: I bought a Rolls Royce and want to build it.

darkostoj wrote:
rlchv70 wrote:
Spank wrote:

what about an inline thermostat housing?
https://www.amazon.com/Meziere-WN0071-I … B003NDFEC0

Use this or make your own.

The Engineer is correct, generally, the more radiator passes, the more efficient, but has a greater restriction, heavier, and maybe thicker.

I don't think i'll be able to fit an inline housing....however I got to thinking and I may try mounting a thermostat housing on the radiator and not the engine.

You could get OLD school cool with this with thermally activated grille bars like an old...Packard, I think.

Shut airflow off to the radiator until engine temp comes up, and then the vents/bars open. Easy to control by hand, easy to control by actuators and maybe an Arduino, harder but hella awesome to actuate with expanding metal like the old school cars did it.

Slap a small restrictor plate on the water pump outlet if over pressurizing with the pump is a concern and you're good to go.

The League of Legitimate Nigerian Businessman - Admiral General Captain
1972 Ford Pinto Wagon - Heroic Fix, 2019 Tony Swan Memorial

"We took the green and the checkered, but everything between that was pretty sketchy."

765 (edited by darkostoj 2019-09-16 07:18 PM)

Re: I bought a Rolls Royce and want to build it.

Hey guys, something strange happened.

We got a trophy for winning something, and not sucking the most like the last 2 trophies.

Ran the Autoweek Empire Hill climb in Michigan. There was a lot left in it, but it was a little hairy running through the woods at 100+mph and I suck at driving. Still won vintage class and was at the top of the pack with street tires where everyone else was running slicks.  Overall a very fun event.

https://youtu.be/omyViByjj5o

https://i.imgur.com/BvVBtsN.jpg

https://i.imgur.com/6sEAC5y.png

https://i.imgur.com/WTlJ6uY.png

https://i.imgur.com/WFBoGYz.jpg

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award

Re: I bought a Rolls Royce and want to build it.

I love this shot!

https://i.imgur.com/WFBoGYz.jpg

Re: I bought a Rolls Royce and want to build it.

Congrats on the win.


And god damn I need that steering wheel in my life.

20+ Time Loser FutilityMotorsport
Turbo Dodge Powered E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: I bought a Rolls Royce and want to build it.

Badass

Homestead Chump 5th-Sebring 6th-PBIR Lemons 9th - Charlotte Chump  CrashnBurn 9th
Sebring 6th again -NOLA Chump 1st -PBIR Chump Trans Fail 16th
Daytona 11th - Sebring 6th - Atlanta Motor Speedway 2nd - Road Atlanta Trans Fail 61st-Road Atlanta 5th
Daytona 13th - Charlotte 9th - Sebring 2nd-Charlotte 25th broken brakes - Road Atlanta 14 10th-Daytona 14  58th- Humid TT 19th Judges' Choice!

Re: I bought a Rolls Royce and want to build it.

darkostoj wrote:

Hey guys, something strange happened.

We got a trophy for winning something, and not sucking the most like the last 2 trophies.

Ran the Autoweek Empire Hill climb in Michigan. There was a lot left in it, but it was a little hairy running through the woods at 100+mph and I suck at driving. Still won vintage class and was at the top of the pack with street tires where everyone else was running slicks.  Overall a very fun event.

I think the universe is trying to tell you to stick to events that are 25s or shorter in duration. Have you taken it to the drag strip yet? (-;

seriously though, nice work!!!

"THE WONDERMENT CONSORTIUM"
Everything dies baby that's a fact,
But maybe everything that dies someday comes back?

Re: I bought a Rolls Royce and want to build it.

2 thumbs up!!!

Silent But Deadly Racing- Chief cook and bottle washer, Former Flyin Turd Race Team Captain 
Ricky Bobby's Laughing Clown Malt Liquor Thunderbird Turbo Coupe, Datsun 510, 87 Mustang (The Race Team Formerly Known as Prince), 72 Pinto Squire waggy, Parnelli Jones 67 Galaxie, Turbo Coupe Surf wagon.  (The Surfin Bird)
Besmirching race tracks in the Eastern US since 2001

771 (edited by darkostoj 2019-09-25 05:45 PM)

Re: I bought a Rolls Royce and want to build it.

So. We will be at the october Gingerman Race.

In hopes of not blowing up our third engine we made a few changes.

1. went from 0-40 to 20-50 and over filled 1 qt
2. went back to an OEM computer with factory tune
3. ditched the air/air oil cooler and went with a factory water/air heat exchanger.  This also freed up room in front of the radiator for less obstruction
4. Ditched the Power steering cooler that was also in front of the radiator blocking things.
5. Adding hood vents off a IROC Z

IROC Z

https://i.imgur.com/Gq5xHal.jpg

6. Adding accusump

https://i.imgur.com/98q2aGh.jpg

7. Limiting RPM to less than 5k and going to shut down car if temps get over 220

See ya there boners

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award

Re: I bought a Rolls Royce and want to build it.

Made some changes.

:fingerscrossed:

moved ps reservoir to not be a half mile away from pump

need to bend up a new ECU mount since the PS res is in the way now

went to a factory throttle body instead of the aftermarket one

the AN hose from the accumulator needs to be a little shorter. (don't like the bend in the line)

I ran the accusump hose to that location because it was much cleaner and I wasn't super happy with running another hose down to the port on the side of the engine and having this massive bulkhead of AN fittings.  You guys think it will be OK there?

https://i.imgur.com/nRmGGSm.jpg

https://i.imgur.com/O8egeHc.jpg

https://i.imgur.com/kzUP7oP.jpg

https://i.imgur.com/GhhwMw1.jpg

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award

Re: I bought a Rolls Royce and want to build it.

I found that hood vents off an 80's IROC Z are basically built for this car.

https://i.imgur.com/SZlj0lJ.jpg

https://i.imgur.com/DTWOVs2.jpg

https://i.imgur.com/msSht2X.jpg

https://i.imgur.com/iqYzqWC.jpg

https://i.imgur.com/XVCUyT5.jpg

The car never ran enough to have to worry about fueling, but hopefully we have better luck this time around.  I built a new filler neck and positioned it in the OEM opening higher up because we were having a really tough time getting fuel in the tank with the quarter mounted filler since it was too low.

https://i.imgur.com/OJmRtrU.jpg

https://i.imgur.com/3v5OHAm.jpg

https://i.imgur.com/z8ORbpS.jpg

https://i.imgur.com/5dHTdgM.jpg

https://i.imgur.com/UYIYoIB.jpg

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award

774 (edited by TeamRadicus 2019-10-07 06:07 AM)

Re: I bought a Rolls Royce and want to build it.

nm pics didn't load quick enough :-)

#98 Oldsmobile Ninety-Eight - Class A car in the hands of a Class D team - MSR Houston IOE!

Re: I bought a Rolls Royce and want to build it.

Hey guys, just wanted to drop an update on the last Lemons race we did.

We were at Gingerman October 12-13 for the Tony Swan Memorial Race.  I had spent all week frantically trying to get the AEM dash to communicate with the PCM.  I had got rid of the AEM ECU and went back to an OEM engine harness & engine harness.  I painstakingly put it all together without one splice or connection in the factory harness because I wanted to be able to quicky swap into a spare considering all of the problems I've had in the past with engine wiring/computers.

I built jumper harnesses and I spent a couple days, but could not find the OHM sensor scaling for the life of me and ended up at the last minute having to install dual sensors for everything I wanted to keep track of and running a separate gauge harness.  I got it all together, and the AEM can module had something wrong with it and the tach along with the fuel level sender weren't working.  I ended up plugging in a bluetooth dongle into the OBD port and using the torque app on a phone so we had RPM.

So in the end we had Tach on a cell phone sitting on the center console, coolant temp, and oil pressure.

We got all the gauges working well enough for the race, and it started to downpour like crazy, so we waiting for a window and did about 5 laps to make sure the car would work OK for the start of the race.

We started race day really easy and babied it around track, and progressively started to lean into the car more and more as the day went on, and our fear of blowing up a third engine started to go away little by little (was always there though)

By the end of the first day we had realized this car has no chance of ever being competitive EVER in this series since we were running about 20 gallons per hour, and had to pit a total of 5 or 6 times for fueling in a 24 gallon cell. We would get about 1 to 1.5 hours on a tank.

At the end of the first day we started having a problem of breaking up at above 3500.  We pulled all the plugs and found #10 was severely oil fouled. We put a brand new set of plugs in and started out strong on the 2nd day. Car started breaking up again and found that the same plug was oil fouling.  Thinking the engine either has bad oil rings, or a leaky valve seal on that cylinder.  Will need to do a compression and leak down test to see what's going on.

Car was still not setup at all in regards to the suspension, damping, alignment etc and we managed to click off 5th fastest lap with the car running on roughly 70% power. The car basically ran the whole time, and the hot idle oil pressure at the end of the race was the same as the beginning (victory!!).  Very happy we were granted the IOE!

Have a lot more things to work out, and hopefully if everything goes right we can win class C, then end up in B and pretty much never win class ever again. lol

Working on some in car footage & pictures.  Will update shortly.

Team Pacific Motors - 1977 Rolls Royce Silver Wraith
2018 Where the Elite Meet to Cheat - Organizer's Choice Award
2019 Rust Belt GP - Spirit of Entropy Award
2019 The Tony Swan Never-Say-Die Memorial - Index of Effluency Award