RS heater bypass: myth busted.
#1
Race Car
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So I had to drive my car this morning, just before dawn. It was 31 degrees outside. I've been worrying about this day coming because of all the collective wisdom here saying that you don't get decent heat with the RS bypass pipe.
Myth busted. As soon as the car was at operating temp, the heat was pumping out nicely. You don't get the rush of air from the rear heater blower. But the car warmed up so much in about 10 minutes, I had to turn the heat off.
So, if you never drive your car in below freezing temps, don't be afraid to lose the 15 lbs of blower lump in the back....
Myth busted. As soon as the car was at operating temp, the heat was pumping out nicely. You don't get the rush of air from the rear heater blower. But the car warmed up so much in about 10 minutes, I had to turn the heat off.
So, if you never drive your car in below freezing temps, don't be afraid to lose the 15 lbs of blower lump in the back....
#2
Banned
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Ok, good news.
I want to do this mod soon with the Fabspeed carbon fiber unit. Does the defroster for the windshiled work without the blower? Also what about the AC-does the fan speeds work without the blower?
Thanks Rich
I want to do this mod soon with the Fabspeed carbon fiber unit. Does the defroster for the windshiled work without the blower? Also what about the AC-does the fan speeds work without the blower?
Thanks Rich
#4
Race Car
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A/C works perfectly, as long as it's in the fully cold setting (all the way anti-clockwise.) When it's up off the stop, fan speeds are lower, but cold air still flows.
Here in Florida, it's either full cold, or off...
Here in Florida, it's either full cold, or off...
#5
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The only problem with mine is the defrost...
It does work... It just works really well with the additional rear blower...
I notice the heat and defrost work better with a little revs...
AC is good...
I still think its worth it!
It does work... It just works really well with the additional rear blower...
I notice the heat and defrost work better with a little revs...
AC is good...
I still think its worth it!
#6
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Interesting. I posted this question on the RDE board: https://rennlist.com/forums/racing-a...s-raining.html
#7
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I have the RS heater piece, and discovered an easy way to make it about 100 percent more effective: put a piece of black tape over the cowl vent during the winter. (The cowl vent is the grille at the back of the hood.)
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#8
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#9
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My main concern with the bypass tube is not the loss of heat but the loss of engine cooling that the fan provides in the hot summer months. I guess in cooler climates this isn't an issue.
#10
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I discussed this with ViperBob prior to doing the mod. His contention, and mine now, is that there can't be much cooling going on. Think about where the blower sends the air: Over the headers. How can blowing ambient air over the headers for a couple of minutes cool the engine enough to make a difference? It's not like it cools the heads, cylinders, or case...My engine didn't run any hotter this summer than last here in Tampa.
#12
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I used the relay bypass to get the full range of the fan working again.
https://rennlist.com/forums/993-foru...pass-tube.html
I also cut the bypass tube on the side to insert the temp coil on the side of it so the CCU sees the correct temperate.
https://rennlist.com/forums/993-foru...pass-tube.html
I also cut the bypass tube on the side to insert the temp coil on the side of it so the CCU sees the correct temperate.
#13
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I discussed this with ViperBob prior to doing the mod. His contention, and mine now, is that there can't be much cooling going on. Think about where the blower sends the air: Over the headers. How can blowing ambient air over the headers for a couple of minutes cool the engine enough to make a difference? It's not like it cools the heads, cylinders, or case...My engine didn't run any hotter this summer than last here in Tampa.
If somebody eventually runs a test, I might change my mind.
#14
Race Director
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this is one of the dumber mods out there for a street car in my opinion. Saving maybe 15lbs (which you won't feel) at the expense of proper hvac operation.
I doubt porsche would turn the rear fan on with the car not running for no reason. Obviously it saw some benefit to this fan for cooling.
I doubt porsche would turn the rear fan on with the car not running for no reason. Obviously it saw some benefit to this fan for cooling.
#15
Rennlist Member