Originally posted by Chadwickus
How did you determine this with just a 0-100km run?
Time 0-100 and with this calculator:
Did 13 seconds flat previously and got it down to 11.73. Before any of those mods, acceleration was 17 seconds to 100 kph. Most of the improvement
came from tweaking the auto transmission cable. Not mentioned previously is I used a street racing oil and 1 step colder spark plugs for the test so I
could red line the engine safely. Got no money to spare for dyno so I think that'll do!
The test car(my daily), a '96 Toyota Starlet could do 40+ mpg(even without any mods) Is not supposed to be a high performance car. But it's quite
fun, reliably boosting this fuel saver with only very little spent.
Originally posted by TrueInstinct
That's pretty good if you're getting that much of a performance boost out of it. Interesting to see how it holds out in the long run though.
About 8000 kilometers(severe conditions) traveled now with those mods and checked engine and mods. Idle: within specs, vacuum: ok, coolant and oil:
normal and no mixing, spark plugs: shows combustion is perfect
...The mods themselves did not change a bit.
Originally posted by Majestyka
hmmm intake too hot to touch leads me to believe you have throttle body injection and hot coolant in a jacketed intake manifold to help vaporize
fuel..... ideally this is how they are designed to operate. this is confirmed by the black hoses running off your intake manifold to your head.
modifying to cut off the flow of coolant to the intake manifold will cause you problems in cold weather. also reducing coolant flow to the head.
Thanks for pointing this out
The engine I have is a Toyota 4efe. The fuel injectors are right in the cylinder head so there's little chance of
fuel getting to the manifold if any. The throttle body does not contain any fuel lines, only small vacuum hoses. No vaporization issues so far -
which will reduce fuel economy and cause the cat to overheat. In fact, as I've stated earlier, fuel economy improved with this mod.
In the case you've pointed out, then don't do the coolant bypass mod on a carbureted engine as manifold and T/B heat does help in vaporization and
prevent carb icing. I'll add your concern in the linked page as a warning(I can't edit my OP anymore)
I did some research on throttle body coolant flow beforehand on an EFI engine. What it does is to prevent freezing in very cold weather and cause the
throttle to get stuck. In actual conditions, the intake manifold and throttle body is still getting radiant heat from the engine(after running the
car at high throttle at working temps and quickly getting a reading at night). My estimate is that it would take an ambient temp of -10'Celsius to
cause freezing issues down the throttle body.
Just to be safe, if temperatures in your region is expected to drop below -5 Celsius, then skip the throttle body coolant bypass part! And don't
bypass coolant on a carbureted engine (only applicable on EFI engines)
edit on 20-6-2011 by ahnggk because: (no reason given)