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Old 8th November 2007, 18:06   #91
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Default wow!

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Originally Posted by Ford Rocam View Post
Will be glad to help but only on saturday & sunday, my hectic work schedule does not give me enough time on week days to test around.
Will also need access to Racedynamics ECU software along with other detailed work carried out on engine.

The thing is what i have observed is people have standard list when it comes to mods, 285 Cam, Bigger T.B, Porting/polishing etc,etc.

It doesn't work that way.
One needs to understand the airflow basics before suggesting any mods & how the engine will respond.
Engine producing good grunt at lower rpm is mainly for cars to toss around city traffic where torque is more important at lower rpm but as when RPM increases the torque curve starts falling.

No wonder this type of engines have long runners at intake manifold to help max air flow at lower rpm. but this kind of manifold is not good for higher rpm. when you increase size of throttle body you are actually hurting low end performance cause you loose velocity which helps cylinder fill air at lower rpm, no doubt it will be good for higher rpm if engine combination permits cause you are increasing the volume.

And when you add CAM like 285 Spec to this type of engine the airflow which is already reduced due bigger T.B suffers more due to cam overlap at lower rpm the air entering combustion chamber further reduces there by giving sluggish performance at lower rpm. & when CAM kicks in at around 4-4.5K RPM the long runner intake manifold is a restriction to air flow. Using adjustable CAM gears you only play around with the powerband & with single CAM there is not much much option you either advance it for better low rpm or retard for better higher RPM, CAM gear adjustment will not give same results on different engines as all engines are not same, CAM settings which is good for one will not be good for other.

According to me the mods should be carried out depending upon the engine combination, bore/stroke, R/S ratio, cyl head design & intake manifold & T.B combination.
If you do it right then minimum modifcation will give maximum results.

Jitu
wow!
i wish we have some more pals like him on our forum who understands the basics of automobiles to the core and have ability and willingness to share it with friends!
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Old 8th November 2007, 18:24   #92
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Default some tips, if u dont mind!

hi ,
1>the cold air intake pipe is being heated in your car..cover it with glass wool or asbestos rope <temp will drop more than 20 deg>
2>if possible reduce the cam duration by @ 25 to 30 deg at .5mm lift
3>if not possible then atleast advance the camming by @ 10+degrees it will add the bottom end dramatically
4> drive in stock setting till the lambda sensor kicks in and starts giving reading , then switch to modded fueling /ignition graphs .
5> measure the pressure drop just before the throttle body at max torque rpm at full load in third/fourth gear . if the needle is fluctuating rapidly , then there is a big charge reversion occuring / fooling/ confusing the temp and pressure sensor and misleading both the e c u s .
all the best . keep me posted!
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Old 9th November 2007, 09:32   #93
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Originally Posted by TURBOSAM View Post
hi ,
4> drive in stock setting till the lambda sensor kicks in and starts giving reading , then switch to modded fueling /ignition graphs .

How is this going to help?
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Old 9th November 2007, 13:01   #94
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Originally Posted by TURBOSAM View Post
wow!
i wish we have some more pals like him on our forum who understands the basics of automobiles to the core and have ability and willingness to share it with friends!
Thanks- we do have more pals as you said like "sideways" & "psycho" and they share it with us, as in when required.
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Old 11th November 2007, 15:58   #95
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Default hi

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How is this going to help?
the stock e.c.u. is programmed with all the possible variables taken in to consideration<it can have 50+dimensional graph when it comes to igniion and injection plotting.>
when we modify the engine , many values change drastically. e.c.u.is not aware of the state of air fuel ratio< because of charge reversion, over schvenging>, actual compression ratio/brake mean effective pressure and the in-cylinder exhaust gas recirculation,as there is no way it can get a feed back.
once the lambda starts working properly then e.c.u. can make changes as and on required .
no aftermarket e.c.u. can match the o.e.m. e.c.u. programming when it comes to complexicity of graphs . thousends of super expert man hours with very sophisticated dynos available only to companies, and millions of dollrs are invested in programming a stock ecu so that it works with good amount of flexibillity.
aftermarket e.c.u's , piggy back ecus <even factory race ecus for that matter>cant match the standard mapping as racing cars are expected to oprate within a 3-4 k rpm band by some very expert drivers, and still they have to keep on fine tuning it continously. in fact the N alpha type managenent system mainly used for racing cant allow good driviability in city traffic <no , engine over camming is no the only culprit>
so when lambda will start giving the reading .the aftermarket e.c.u will have a helping hand in adjusting the fueling map if provision is available.

Last edited by TURBOSAM : 11th November 2007 at 16:04.
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Old 15th November 2007, 13:06   #96
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Originally Posted by TURBOSAM View Post
the stock e.c.u. is programmed with all the possible variables taken in to consideration<it can have 50+dimensional graph when it comes to igniion and injection plotting.>
when we modify the engine , many values change drastically. e.c.u.is not aware of the state of air fuel ratio< because of charge reversion, over schvenging>, actual compression ratio/brake mean effective pressure and the in-cylinder exhaust gas recirculation,as there is no way it can get a feed back.
once the lambda starts working properly then e.c.u. can make changes as and on required .
no aftermarket e.c.u. can match the o.e.m. e.c.u. programming when it comes to complexicity of graphs .
Stock ECUs are very complex systems, and its all got to do with emission control. Almost all stock ECUs have a degree of self-correcting ability built into them, and closed-loop lambda is only one of them.

Quote:
thousends of super expert man hours with very sophisticated dynos available only to companies, and millions of dollrs are invested in programming a stock ecu so that it works with good amount of flexibillity.
thousands of man hours + sophisticated dyno + millions of dollars looks impressive, but is not always the case in reality. Just look around the number of relfashes, upgrades and replacements that happen, not to mention coverups .

Quote:
aftermarket e.c.u's , piggy back ecus <even factory race ecus for that matter>cant match the standard mapping as racing cars are expected to oprate within a 3-4 k rpm band by some very expert drivers, and still they have to keep on fine tuning it continously.
If you are talking about mapping for performance and/or drivability you are wrong. If you mean meeting emission regs you are right.

Quote:
in fact the N alpha type managenent system mainly used for racing cant allow good driviability in city traffic <no , engine over camming is no the only culprit>
so when lambda will start giving the reading .the aftermarket e.c.u will have a helping hand in adjusting the fueling map if provision is available.
Maybe you should try driving your car with the Tps and map/maf sensor disconnected


Coming to the point, it doesnt make a difference if Ranjan drives in stock and then switch over. Closed-loop lambda does not work in conditions that need max power.
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Old 16th November 2007, 08:47   #97
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closed loop lambda is not in a loop when one demands max power... but there are very few instences when u can drive at max power!
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Old 17th November 2007, 19:53   #98
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All this technical jargon is too much for guys like me.
Just tell us howz the car running now ?
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Old 26th January 2008, 04:51   #99
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Hey Kumar, you promised a report when you have run the car for a while...welll where are you buddy? I am undergoing the same type of mods so was hoping to see some more content on this thread to get more input...but?? whats up with the car Kumar?
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