Tuning a 3k for economy

[cush]

A relevant thread for today.

What can be done (aside from driving style) to get the highest economy out of a 3k.

How do you tune the buggers anyway?

[Z2TT]

You can adjust the idle speed on the carb.

You could adjust the mixture screws to lean out your mixture, but that wont be good for your valves and exhaust, especially when the car is under load.

Also be sure that your running a clean filter, and that your carb is clean.
If you haven't done so, adjust your ignition timing, and check your spark plugs.

[cush]

I'm looking for specific timings, etc...

[oldcorollas]

stock 3K?
everything in good order?
what fuel?

basically... whichever fuel you use, advance timing until you can just hear pinging around 3-4000rpm (well.. you want to be a bit before that anyway.. maybe 3-4deg)
and screw in the idle mixture adjustment until it runs smoothest, or a liiitle further in.

they typically run rich anyway (esp when modified).

what you could do, is to weld in an O2 sensor bung, and go for a drive with a wideband, and see what throttle/rpm it is rich.. and what cruising AFR's are.. then modify or change the main jets to suit.

but basically, if you are running 98, then 15deg or more should be fine.. but it all depends on the condition of the motor etc..

[Z2TT]

with 30yo motors, just note that when doing timing, the timing marks really dont apply anymore as they did when the engine was new, as the cams, valves, lifters etc are all get worn away. When doing timing you'll have to adjust it so it runs smooth.

[oldcorollas]

with 30yo motors, just note that when doing timing, the timing marks really dont apply anymore as they did when the engine was new, as the cams, valves, lifters etc are all get worn away. When doing timing you'll have to adjust it so it runs smooth.

bullshit.
that is totally wrong.
the timing mark is on the crankshaft pulley.
the other marks are on the timing chain case.
the ONLY way the timing mark is no longer accurate is if the crank pulley has rotated on the crankshaft.
that requires the key to have been munched, and that rarely rarely happens on K motors.

timing chain stretch etc might affect cam timing slightly, but cams, valves, lifters have little to no effect on the spark timing.

if anything, the dizzy rotor will change position relative to the cap, but the timing itself you will set, and the marks on the front are accurate.

i hate to say this, but if you don't know 100% what you are talking about, it is better not to post.

[cush]

easy now..

i'm trying to save the planet here..

[ira11y]

Z2TT you clearly have a very poor grasp of combustion engine mechanics, I suggest before you reply to anyone else requesting help to go and do some reading on the basics.

If your wondering why I am being so harsh it is because a continuation of advice of the type you are giving may lead to someone damaging or destroying their pride and joy due to your negligence.

You can adjust the idle speed on the carb

How is this going to improve economy? do you really think that the 5% of time at idle in a cars daily drive is going make a substantial difference? if a car was over revving at 2Krpm at idle and was backed off to 500rpm the difference over a minute in fuel consumption would be a mere 30-50ml on a K motor.

with 30yo motors, just note that when doing timing, the timing marks really dont apply anymore as they did when the engine was new, as the cams, valves, lifters etc are all get worn away. When doing timing you'll have to adjust it so it runs smooth.

I think OC summed it up very well with one word

bullshit.

Nuff said

[cush]

stock 3K?
everything in good order?
what fuel?

basically... whichever fuel you use, advance timing until you can just hear pinging around 3-4000rpm (well.. you want to be a bit before that anyway.. maybe 3-4deg)
and screw in the idle mixture adjustment until it runs smoothest, or a liiitle further in.

they typically run rich anyway (esp when modified).

what you could do, is to weld in an O2 sensor bung, and go for a drive with a wideband, and see what throttle/rpm it is rich.. and what cruising AFR's are.. then modify or change the main jets to suit.

but basically, if you are running 98, then 15deg or more should be fine.. but it all depends on the condition of the motor etc..

modify jets, you say?

can i get a please explain? how so?

[oldcorollas]

..........

[cush]

..........

Interesting.

The email shows a few more letters than that..

[oldcorollas]

hehheh, i justrealised it is probably not a good idea to encourage you to fuck with the jets if you don't have spares, and don't really know what you are doing...

right foot is best way to save fuel (but if you can afford, chuck it on dyno to see what mixtures are doing before you lean it out)

[web]

easy now..

i'm trying to save the planet here..

Saving the planet would be pioneering a 2SZ/2NZ RWD conversion =)

Making a 3K as economical as possible is mostly saving your wallet =)

[AAAAGZE]

weld the secondary shut in the carby so you only ever operate on primary.

and roll down hills.








and get out and push up hills

-dave

[Gavatron]

It's a 30yo car, therefore, it will not have secondaries. Heck, it won't even run on petrol. Don't you know anything!?!?

If you want your car to be economical, make sure your 3K is supplied with the best parrafin wax you can find. You can tune the wax supply by using the steam powered delivery system. This can be found between the wooden chassis rail and the paper mache inner guard.

Isn't it economical enough already. It's a 1.2 with a pissant little carby on it? Got a 5 speed box? That'll save you more than any tinkering most likely.