4age 16v/smallport Throttle Body Mod Idea

[Kozmo]

The 4AGE is a high compression engine (10.3:1).

High compression + hot day = knocking/pinging.

Knocking/pinging = retarded ignition timing.

Retarded ignition timing = power loss.

 

On a 30+ degree days I notice a considerable power drop (like having the car loaded up to go on holiday).

In an attempt to combat fuel detonation I am already running my car on 95 or 98 octane fuel.

 

Without the use of avgas I can only see one other viable method of trying to overcome fuel detonation - reduction of air intake temperature.

 

On the bottom half of the throttle body, there is a port that runs from one side of the butterfly to the other to give the car more air when cold.

This port is controlled by a thermostat. The thermostat operates like a normal car thermostat, it is hooked into the coolant system and opens and closes at a set temperature.

This idea doesn't make an awful lot of sense to me though...

To the untrained eye it would appear as though Toyota have turned the throttled body and surrounding components into a heat-sink because of it's contact with the vehicles coolant therefore increasing air intake temperature :y: .

 

My idea is to disconnect the throttle body from the cooling system and use a rubber plug to block off the "cold-start air port".

I do realise that this will cause idle issues for me on cold day, but I would be happy to use the idle adjustment screw to keep the car going in the cold.

I also realise that the engine was designed to run at 2500RPM from cold but that just introduces unnecessary wear IMO + I always let my car warm up before driving.

 

Comments on this idea are very welcome.

Especially if you can think of another method of introducing more air on cold start. :jamie:

Edited January 11, 2010 by Kozmo

[930LLO]

Run a cold air intake to the hole that is on the side the battery is on and have it poking through near the left handside bumper blinker.

 

Other than that put a small scoop on the bonnet near the intake to cool it?

[Sam_Q]

try cleaning out your engine as it could be carbon deposits. Apparently a Subaru produce called "sea-foam" is the best

[Kozmo]

Run a cold air intake to the hole that is on the side the battery is on and have it poking through near the left handside bumper blinker.

Thought about the idea, but I am hesitant to run a pod filter in there in case it picks water up of the road.

Might do some testing by fixing something like paper towel in there and seeing if it picks up water on a wet day. :dance:

 

try cleaning out your engine as it could be carbon deposits. Apparently a Subaru produce called "sea-foam" is the best

One of the first things I did when I got the car :y: .

 

Think I might get my hands on a Toyota 4AGE smallport/redtop manual to get a full understanding of the air induction & idle up system before I go fiddling. :y:

[SLO-030]

Thought about the idea, but I am hesitant to run a pod filter in there in case it picks water up of the road.

Might do some testing by fixing something like paper towel in there and seeing if it picks up water on a wet day. :dance:

 

Water on the pod filter + engine bay heat = Evaporation = Cooler intake temps :y:

[Hiro Protagonist]

Thought about the idea, but I am hesitant to run a pod filter in there in case it picks water up of the road.

Might do some testing by fixing something like paper towel in there and seeing if it picks up water on a wet day. :dance:

 

Unless you fully immerse the pod in water (ie you decide to go into a big fat puddle more than say 30cm deep at slow speed), you don't need to worry about the pod sucking up water. It won't cop heaps of spray from the road because it is in front of the front wheel (and protected by the splashguard), and most air intakes will pick up a bit of spray anyway no matter where they are mounted (ie behind the headlight/radiator grille).

 

I've run a pod behind the front bumper with the splashguard pushed open a bit as a makeshift ram-scoop for a good year now, and never had any problems (and driven plenty of times in the rain)

[Sam_Q]

I can tottaly confirm the above, I have for a long time run a pod near the bottom in-front of my radiator and there are lots of puddles here. I never noticed anything hitting puddles or going behind other cars but it did clog up somewhat quick.

[carbonboy]

A neat & easy solution is to get busy with some 1mm aluminium sheet & a pop rivet gun to form up some heat shields for your pod filter,even a semi-box like arrangement can make for a noticeable (i have a digital temp sensor inside my intake pipe just b4 the throttle body) difference when combined with the abovementioned cold air feed. The expensive solution is to build a carbon airbox,but it works much better than the factory item & sounds awesome :-)

[TRD ke70]

Try setting the timing according to the manual.

 

You have to lock out the ECU to set the timing, chucking a timing light on it and setting it won't give you the right timing.

 

There's heaps of engine manuals out there google it!!!