Page 2 of 3
Re: Output Kw?
Posted: Wed Dec 08, 2010 2:52 pm
by Cobvs
You will obviously only switch MAF sensors between the same engines so shouldn't the sensors then be the same or is that what we are saying here that the sensors might differ slightly or same sensors measures airflow with different results

Re: Output Kw?
Posted: Wed Dec 08, 2010 3:16 pm
by Mcnoogle
Cobvs wrote:You will obviously only switch MAF sensors between the same engines so shouldn't the sensors then be the same or is that what we are saying here that the sensors might differ slightly or same sensors measures airflow with different results

Hi there,
No, I think it would have to be the same sensors, (there are a lot of things that the Pajeros and the colts share, bearings etc, I think in this case the MAF sensors as well (which is why the mechanic used his own for the test)
The point I was trying to make is that it seems thet the condition if the MAF sensors / its calibration (dont know if the are calibrated or how they work) obviously affects performance power i.e. prado/Hilux story, so in this case, it at least looks like if Blister puts in a new maf sensor, or reconditions/recalibrates (or whatever can be done)his current MAF sensor, he will be able to increase his power.
I don't think beyond the manufacturers stated power, but definately better than what it currently is.
Re: Output Kw?
Posted: Wed Dec 08, 2010 6:17 pm
by Blister
Mcnoogle wrote:Cobvs wrote:You will obviously only switch MAF sensors between the same engines so shouldn't the sensors then be the same or is that what we are saying here that the sensors might differ slightly or same sensors measures airflow with different results

Hi there,
No, I think it would have to be the same sensors, (there are a lot of things that the Pajeros and the colts share, bearings etc, I think in this case the MAF sensors as well (which is why the mechanic used his own for the test)
The point I was trying to make is that it seems thet the condition if the MAF sensors / its calibration (dont know if the are calibrated or how they work) obviously affects performance power i.e. prado/Hilux story, so in this case, it at least looks like if Blister puts in a new maf sensor, or reconditions/recalibrates (or whatever can be done)his current MAF sensor, he will be able to increase his power.
I don't think beyond the manufacturers stated power, but definately better than what it currently is.
Sorry coming so late into the thread but yes I am convinced that the mechanic is correct that something is the matter with it which contributes to me belonging to the infamous "20l/100km club" besides wasting power

Re: Output Kw?
Posted: Wed Dec 08, 2010 7:38 pm
by colinken
In all applications the airflow meter will rob you of power it is only there for emissions and fuel economy, in a racing application the airflow meter is done away with completely. Generally speaking Kw or Hp = top speed and torque = accelaration a number of facters go into the equation usually to get more power you make the engine rev higher by means of better balancing of components higher compression better breathing cam timing and spark timing.More torque will usually be over square or under square ie longer stroke the mass of the fly wheel also has a effect on torque. If you look at the stats for the GTO motor it is the same as the 6g72 just with 4 valves per cylinder to rev higher
Colin
Re: Output Kw?
Posted: Thu Dec 09, 2010 12:15 am
by HBannink
colinken wrote:In all applications the airflow meter will rob you of power it is only there for emissions and fuel economy, in a racing application the airflow meter is done away with completely. ....Colin
The "airflow meter" can not rob you of power, it is one of the sensors feeding information to the engine management system and is essential in the type of management used in the colt and pajero. Racing engines that do not have them are using a different type of management and their mapping is totally different.
If Blister's vehicle performed so much better with a different mass sensor I would suggest that his sensor is faulty and could be the cause of the high consumption. An engine running rich not only uses too much fuel but also under performs causing longer and more full throttle to get the required performance resulting in even more fuel used.
To get back to the original question regarding output, it is all in the design of the engine and is a combination of various components. Longer stroke generally produces more torque and lower rpm and multi valves will in general produce peak power at higher rpm. short intake headers produce a lot of power at high rpm while longer headers does it lower. Airflow in a motor also has a big effect in the power range and output so it is difficult to point to one culprit.
I have the import 6g72 in my pajero and my compression is higher than our local unit with a slightly higher output and torque on the dyno (I can not get what the specs claim but it is slightly higher than standard). In our application we should rather look at torque as this is what we "use" rather than performance. My platkar produces 244kw from a 2l motor and would run circles around the v6 but I don't think it would get the pajero up a tarred hill never mind a sand dune
Re: Output Kw?
Posted: Thu Dec 09, 2010 6:35 am
by colinken
Now we opened a can of worms, a airflow meter is a restriction in the inlet passage thus robbing a high performance application of power. If one used a stand along management system one would not use the airflow meter it is only there in a road application to measure air flow for pricise fueling for emissions and economy abviously if one had a fault in the airlfow meter you would loose even more power. All performance fuel injected motorcycles do not used air flow meters most have ram air tecnology a air flow meter would restict this.
Re: Output Kw?
Posted: Thu Dec 09, 2010 8:40 am
by Cobvs
The Colt and Pajero use the wire type MAF sensor which with the use of heat measures resistance and feedback that info to be used by the Engine management System to determine fuel mix (ala Wikipedia

). Apart from cleaning with carb cleaner I am not sure how it can be fixed.
With regards to restriction Jenki I am not sure if you refer to physical restriction (wire sensor -quite small and beehive metal plate - which I assume is to distribute the air evenly past the sensor) in the air flow channel or restriction/control exercised by the EMS based on the info from the sensor. I always was of mind that the airflow is used to get the most accurate fuel mix for optimum ignition with economy as benefit.
Hbannik that is part of my curiosity as to why your import have slightly higher compression and output than local. If the engines are exactly the same there must be some component or other restriction in our machines that limits the output in some way. It is was only EMS then you should have been able to get it the same on dyno?
Re: Output Kw?
Posted: Thu Dec 09, 2010 9:48 am
by Mcnoogle
colinken wrote:Now we opened a can of worms, a airflow meter is a restriction in the inlet passage thus robbing a high performance application of power. If one used a stand along management system one would not use the airflow meter it is only there in a road application to measure air flow for pricise fueling for emissions and economy abviously if one had a fault in the airlfow meter you would loose even more power. All performance fuel injected motorcycles do not used air flow meters most have ram air tecnology a air flow meter would restict this.
Ok, I agree with you about the 'can of worms, and were drifting of the actual topic.
I will start an new thread regarding the MAF sensor, as this is an issue that both Blister & myself ar trying to address.
IIRC the original question posed on this thread was what creates power KW, and what creates torque Nm
Re: Output Kw?
Posted: Thu Dec 09, 2010 10:44 am
by 4ePikanini
Mcnoogle wrote:
IIRC the original question posed on this thread was what creates power KW, and what creates torque Nm
That's simple. Torque is the ability of the engine to create force on the piston/crankshaft. KW is that torque multiplied by RPM.
So ....... if you have loads of torque you won't need rpm. Racing engines rev higher because they gain more by having less torque and higher rpm, than more torque and lower rpm. This balance is slowly shifting as diesel engines become lighter, more efficient and create more torque (Le Mans Audi Diesel is a good example)
PS : not to drift to petrol versus diesel again but....... chemically, diesel has more energy per liter than petrol -
THAT'S A FACT!
Re: Output Kw?
Posted: Thu Dec 09, 2010 12:45 pm
by Cobvs
The question is also why would two basically same engines produce different KW: examples -GTO 3.0 V6 24V with +-165 kW against 3.5 V6 24V with +- 153kW (figures approx)
Hbannik's 6G72 import against local Samcor 6G72 (no figures) or basically how do the one produce more or less kW than the other?
@4eP
Why does diesels produce more torque but lower kW than petrol? is it purely because of lower RPM