Received my radiator and electric water pump yesterday.. that means my cooling system is complete.. :woot:
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Received my radiator and electric water pump yesterday.. that means my cooling system is complete.. :woot:
Wow. It would be nice if 35-40% of the RAD wasnt covered. The fan is only needed when at low speeds and/or standing still. The shroud then becomes a restriction from a relevent aero speed, which on our chassis is around 27mph.
So you would have an issue with this design as well:Quote:
Originally Posted by chicane67
https://static1.pt-content.com/image...RADIATOR-1.jpg
I would have to measure to see how much of the radiator is covered.. which is relative since none of it is really covered (ie, blocked. When the fan isn't spining and your driving at speed I would think enough air would pass through the fan opening to cool the car. Also, if there is a "bit" of back pressue that shouldn't be an issue so long as enough air is moving past through the radiator.
I guess my point is "so what" if the shroud is a bit of a restriction so long as a suficcient volume of air is moving through the radiator. :)
Looks nice, how many CFM does the fan pull?
Gerald
Well, if one were to take into consideration of the creation of negative pressure behind the core support...... then no, it wouldnt be too much of a problem.
The problems with cooling are mainly at low vehicle speeds, which should be considered for street driving. Any restriction beyond the natural core flow resistance can impeade on the systems performance. Unless....... you have introduced something to combat the pressure difference needed to improve air flow thru the core itself. A good example is any late model. There isnt much of an opening in the front body and their implimentation of air dams under the core support and venting the underhood pressures via side exhaust ducting (like that on the C5/6) does wonders for drawing air thru the core. Without this help, they would cook.Quote:
Originally Posted by Steve1968LS2
Air flow exposure to the total core area is the key.
For a street chassis, I might agree with this. But, not for a chassis that is going to see any track time. And we know Penny isnt going to be just a street queen.... right ??Quote:
Originally Posted by Steve1968LS2
I don't think there will be a problem. Given that the engine I am running is all aluminum and sheds heat well (besides the fact that LS1 enjoy a higher temp than say a traditional SBC). The fan is ran off a temp sensor inthe radiator so if the temp goes up to far the fan will come on and pull more air through, regarless of the speed of the vehicle.
Also, I will get a small gain in air flow from the DSE Closeout (more air forced through the radiator rather than up).
AFCO is not (by far) the only performance radiator company to use shrouds of this type.. If if turns out to be a problem at the track I will come up with another idea. The other benefit is that my water pump is consistent and any speed since it's electric.
In Laymans terms Your fan when running withPenny at say 35 mph or faster will act as a solid object blocking air from passing through your core.
Look at spals set up it contains "blow off" doors that pop open when the pressure in front of the fans exceeds the pressure behind the fan.https://static1.pt-content.com/images/noimg.gif
BTW I cant see thumbnails for some reason so I cant see your first pick just the second one
I was wondering if someone was going to make this point,which is important.Quote:
Originally Posted by LowBuckX
I think you diagram makes it look a "bit" worse than it really is since you show ZERO air going through the fan opening. Also, if this occured and the temp climed wouldn't the fan then kick on and pull the air through the area?Quote:
Originally Posted by LowBuckX
Also, wouldn't this mean that most radiator mfgs (including Ron Davis, AFCO and others) know less about radiator design than you do ;) lol
Actually I guess that would be "less about shroud design".. Are you saying that I should add rubber "blowout" flaps like on the plastic SPAL fan deal?
I will call a couple radiator guys I know and pick thier brains on this. Might be a good excuse for a story on cooling theory.. could call it "keeping your cool". Can I use your artwork? :D
I'd be interested in what you find out, Steve. I am about to send my Griffin radiator to them to have a shrould made and attached.
If my memory serves me correctly, shrouds are required for mechanical fans only and can be considered restrictive otherwise. This is not my opinion but that of many a racer. Fans are only for low speed air flow and are not required above 35 mph. Yes a idle fan is restrictive – just put your hand out the window doing 50 mph and you'll get an idea, however I think we are approaching more cooling theory than general purpose as which I think penny will most likely see (track and street). Ideally a radiator will work most effectively when unrestricted airflow touches all the fins.
All this to say that you will be fine.:jump:
Now that's funny. I also concur with the "pressure flaps". Call it useful insurance.....Quote:
Originally Posted by Steve1968LS2
If you end up doing an article on this, be sure and contact Chet at C&R besides the previously mentioned guru's.
Allow me to include a statement of a system that beats the shroud theroy. It was a system I worked up with one of our own:
And I believe Andrew's comment, sum's it up nicely.Quote:
Originally Posted by CarlC
No matter what Steve, your approach to the build of Penny is uber bad @ss.
True but wouldn't the fan blades (when the fan is off) be less of a restriction since they move/spin (unlike your hand out the window.)Quote:
Originally Posted by harshman
Remember, Penny is NOT a race car.. she is a street car that will hit open track days and hopefully a few open road deals.
In any event it's a good discussion :)
Oh, will the fact that I am running an oil cooler take some pressure off the coolant system? I would think so since cooler oil would equal a cooler engine and thus cooler coolant..
you forgot about the motor.
My 2cents....
Spal's not the only one to use flappers. Check out the 4th-gen V8 cars. They have the flaps. GM would not put them there unless there was a reason.
And another one of those reasons? Reliabilty. If the car has to rely on the fan to keep it cool at constant-street and freeway speeds it will lead to significantly reduced fan and alternator life. A few rubber panels are a lot cheaper than replacing expensive electrical components.
Mine has a LOT of cooling capacity.
So the $100k question would be how could one install "flappers" onto an aluminum shroud.. hmmmQuote:
Originally Posted by CarlC
Ideas?
Scissors :2nd:
Quote:
Originally Posted by harshman
:getout:
lol