tb coolant bypass modification results

[statultra]

if you are driving in traffic, heatsoak becomes a major issue with the toyota prius, since the engine shuts off and the water pump cannot pump the antifreeze out of the engine, thus increasing the temperature of the coolant.

then when the engine fires up the hot coolant gets routed through the cooling system thus increasing the intake air temperatures, although colder air intake temps will yield a richer mixture ( i think ) it really helps in the summer.

the difference in the IAT can be observed after cruising, and driving through traffic where the IAT rarely gets above 110 degrees, versus before where it would range from 120-140 degrees in traffic with an ambient temperature of 93.

as some of you know in florida the rainy season is in full swing, and temperatures drop as much as 20 degrees when a storm is above you. during a 75 degree ambient temperature my IAT was between 85-90 degrees.

now this isnt a totally scientific experiment, but none the less the intake air temps are vastly lower than it was before the modification was completed.

i notice more low end torque in very hot weather.

[alanh]

Originally Posted by statultra

i notice more low end torque in very hot weather

How do you measure the torque of the ICE?

[statultra]

i could feel the "pulled back into the seat" feeling.

its more noticeable than before, in hot weather I would get bogged down in traffic.also, im pretty sure its not psychological.

[bwilson4web]

How about two test runs:

0-60 mph - w/o mod
0-60 mph - w mod

If there is more 'umph', the times will tell.

Bob Wilson

[F8L]

Originally Posted by bwilson4web

How about two test runs:

0-60 mph - w/o mod
0-60 mph - w mod

If there is more 'umph', the times will tell.

Bob Wilson

The battery SOC would cause issues with this test as well as the fact I do not think there is enough of a HP/TQ difference to have much effect in 0-60' times. My times were all over the place when I raced mine on a certified race track. I ran it 14 times I believe.

[statultra]

ill do a 0-60 with modification, whenever i get a chance

im going to do it on my 2001 prius, without mod and with it

[MR.K]

Is it possible to put a valve to shutoff the water for summer months or when the water goes out of the T/B do it go some where else vita to the rest??

[V8Cobrakid]

i was going to ask that.. hehe.. a valve. btw, link this to your previous topic. I would like to see pics ( if you included them) hehe

[alanh]

Originally Posted by statultra

i could feel the "pulled back into the seat" feeling.

its more noticeable than before, in hot weather I would get bogged down in traffic.also, im pretty sure its not psychological.

The reason I asked is that the "seat of the pants" feeling is highly subjective, particularly on a throttle by wire car. The Prius in particular is going to siphon off a variable amount of power depending on the battery state of charge.

[statultra]

I noticed the performance advantage specifically
when battery levels were just 2 bars.
Im going to post some 0-60 times taken by GPS, not sure how accurate it is but we will see.