throtle body

nasser · Post by **nasser** » Fri Aug 01, 2003 9:57 pm

I have a 1.6 lanos and I want to swap the throtle body with a beter air flow one. Any sagetion?

mocpac · Post by **mocpac** » Sat Aug 02, 2003 1:32 pm

Nubira trottle, will fir exacly. :twisted:

daewooluvr · Post by **daewooluvr** » Mon Aug 04, 2003 1:39 am

what is the size of the lanos TB and the nubi TB?

Also, if the Nubi TB will fit the Lanos, wouldn't that in turn say that the Leggy TB would also fit?

mocpac · Post by **mocpac** » Mon Aug 04, 2003 2:36 am

Yep you are 100% right also the legy not sure about he 2.2l but I think that one will fit also. . :twisted:

daewooluvr · Post by **daewooluvr** » Mon Aug 04, 2003 11:50 am

daewooluvr wrote:what is the size of the lanos TB and the nubi TB?

Can anyone find the difference in sizes?

TheGreatAndPowerfulOz · Mon Aug 04, 2003 3:56 pm

Is this the throttlebody that I circled in yellow?

If so, what kind of improvement will be made using a Nubira one on a 1.6L Lanos?

daewooluvr · Post by **daewooluvr** » Tue Aug 05, 2003 5:38 pm

yes that is the TB. What we need to have measured is the inside diameter and comare the two to see how much of a difference there is, how much of a wall there is (in case we want to have it bored over more) to effectively know how much of an increase we'll see.
I know for my car anyway I will see a large increase as my car runs really rich even when it was stock.

Bringrice · Post by **Bringrice** » Tue Aug 05, 2003 5:55 pm

daewooluvr wrote:yes that is the TB. What we need to have measured is the inside diameter and comare the two to see how much of a difference there is, how much of a wall there is (in case we want to have it bored over more) to effectively know how much of an increase we'll see.
I know for my car anyway I will see a large increase as my car runs really rich even when it was stock.

Has anyone tried to bore the Intake Manifold or is there another larger IM we can put in our car that will fit?

TheGreatAndPowerfulOz · Tue Aug 05, 2003 9:11 pm

Damnit! I went back to the junk yard today to get the throttlebody off the Nubira that was there, and it was allready off the lot and on the stack of cars next to the crusher so I couldn't get it!

I'll have to wait until I get lucky & run across another Nubira, which I don't think will be any time soon because that was the first Daewoo I have ever seen in any of the junk yards I freequently visit.

Post by **PrecisionBoost** » Wed Aug 06, 2003 4:45 am

With regards to larger throttle body replacement I would be cautious if you don't know what your doing.

Given the Lanos has a MAP sensor I was thinking that changing the throttle body size is going to throw off the factory PCM air/fuel maps. The factory PCM fuel maps are based upon MAP sensor numbers which correlate to a particular air flow level with the stock throttle body. By changing the throttle body size you change the air flow levels without the PCM knowing it. (since it can't measure air flow only pressure)

If the car had a MAF sensor for sensing how much air is going through the engine it would be a different story as the PCM would be able to accomidate the new higher flowing air mass and add the appropriate fuel by increasing the injector pulse width.

As far as I'm concerned increasing the bore of the throttle body is going to do two things

1) increase throttle response to make it feel like the car has a faster response

2) the air/fuel ratio is going to be out to lunch and the car is going to run "lean" unless you do one of two things

a) increase the fuel pressure

b) use a significantly higher octane level

If higher octane levels were used (say 91 octane) with a bored out throttle body you would definitly make a couple of horsepower and feel the better throttle response.

A little larger bored out throttle body is ok because it doesn't change the air flow that much but if you drop in a throttle body meant for a much larger engine (like the Leganza) you are asking for trouble.... you might end up with detonation under full throttle high RPM situations and engine will die a horrible death.

I'd be curious as to the difference in size between the Nubria and Lanos throttle bodies. Given the 2.0L is 25% larger than the 1.6L it's reasonable to assume that the air flow will also be 25% more. I personally would get an adjustable fuel regulator for that much of an increase.... I just don't think a jump from 87 octane to 91 octane would be enough to keep the engine from going lean when the throttle body butterfly is fully open. (when the gas pedal is pinned to the ground)

daewooluvr · Post by **daewooluvr** » Wed Aug 06, 2003 1:28 pm

I honestly don't thinkt he the sizes will be much different. Yes the engines are bigger but they are tamed down. I'd say if you're only changing the TB that it would be bad but if you have other mods that would correlate than I would think that you're safe. For instance, if you have a Daewootech AITS chip then you're safe because it's dumpin' more gas than it normally would. Anyone with an A/F meter will see that our cars normally run too rich. So this may even it out a bit more but again I wouldn't recommend swapping this part without knowing what you're doing.

gti_7 · Post by **gti_7** » Thu Aug 07, 2003 3:39 am

From the way i see it.. not to tread on anyones toes..

With a bigger TB, more air is going to be introduced. granted, and with that more fuel, why? the 02 sensor. Its going to sense the level of air to fuel in the exhaust and adjust the level according to the preset tables in the ECM.. the only side affect i can foresee is an increase in fuel comsumption.. its the same idea behind having a CAI.. more flow and density of air creates from power. its not going to cause anything catostrophic.. its the way i see it anyway.. the OBDII is a pretty sophisticated piece of work

Bernard

mocpac · Post by **mocpac** » Thu Aug 07, 2003 1:49 pm

You are 1000% right!!!!

Any one here who use a Intake in his or her car know the difetence. If the trottle is also more biguer .5" or more, more air will enter in the engine and as gti_7 said the sensor will report this to the ECU and the ecu will send more gas. So for those who think if they remove the sensor will get more boost, you are WRONG. But that is another theme :twisted:

Post by **PrecisionBoost** » Sun Aug 10, 2003 1:57 am

All I'm trying to say is that you can hit the end of the factory fuel maps if you go with a much larger throttle body since the MAP sensor can't sense the increase air flow only pressure level in the manifold.

Ok.... here is what I'm getting at.

Say your stock Lanos throttle body lets 150CFM through at full throttle at say 5000RPM (butterfly totally open)

This 150CFM might be equivilent to say 80% open on the much larger throttle body..... so what does the PCM do when it goes past that 150cfm level and the pressure drops below the theoretical maximum MAP sensor reading?

The larger throttle body will work just great up to the 80% point....and then the PCM is going to be lost because it's fuel maps stop shortly after this 80% point.

The PCM designers probably extended the fuel maps a little past the theoretical maximum flow level ( with a stock throttle body ) but who knows how much.

Once the reading "hits the wall" at the end of the fuel map the PCM isn't going to be able to change the pulse width of the injectors any further and the engine is going to go into a lean burn as the air flow increases further.

The O2 sensor is just a feedback mechanism....once the fuel map has reached it's end the PCM can't add more fuel no matter what the O2 sensor reads. ( who knows... the OBDII system might do a fuel cut once the sensor reads a Lean level and can't counteract it)

The only way to truely counteract this is to increase the fuel pressure level (via adjustable fuel regulator) or by introducing a higher octane level.

It's a simple fix to add an adjustable fuel regulator which will allow you to stay within the factor PCM fuel maps.

I'd be willing to bet that the cars aren't running rich enough to counteract a Leganza throttle body without modification to the fuel delivery system.

This idea is not much different than turbo charging a naturally aspirated engine.... you need to do some modifications such as using a rising rate fuel regulator and some type of MAP sensor clamp (since the PCM would show and error if it sees a positive pressure)

Post by **PrecisionBoost** » Sun Aug 10, 2003 2:08 am

The other alternative to adding an adjustable fuel regulator or increasing the octane level is to reprogram the PCM with new fuel maps that are extended to accomidate much higher airflow levels.

Doing mods to the airflow side of things without doing anything to the fuel side of things is pure suicide if you ask me.