Tuning query...and more

[Manas]

Hey all !

Corrections welcome http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

While Tuning an Engine : what exactly are we looking to tune : Is it the Air:Fuel Ratio , or the Ignition timing ? ar a combination of both along with changing of internal characteristics of the Engine : viz the cylinder and piston head configuration and geometry , Spark Plug positioning ?

I think the tuning aims at acheiving a non-peaky , flatter Power curve in the working rpm range. Does my interpretation require amendments ?

To what extent do these parameters influence the power curve ? which one influences it the most ?

Is it true that tuning an MPFI engine is more cumboresome than tuning a Carbureted one ?

I have been of the point of view that Dyno-testing comes into the picture only once the car has run a considerable amt of miles . ( ?? )

If intake and exhaust designs are finalised only after Dyno-testing, which ,as i have said(or think), comes after actual running of the car, .... in this case, how is the entire car finalised with the Intake ,and more importantly, the Exhaust absent ? ('cuz they will come in the pic. after dyno tests) !! ??

I believe, i am missing something drastically important here.

Please correct me where ever im wrong.

Which teams sets the working boundary for the other ?? The chasis for the exhaust ? or the vise-versa? I mean to ask, which of these is finalised first ? 'coz exhaust routing becomes painfully combersome after the rear chasis is in place.

I might sound pretty novice: blv me : i am. !

And do Performance Trends softwares really pose more problems than they solve ? I found them to have a pretty small Learning curve : so was going to use them .

Thanx.
\\//, Live Long and Prosper.
Manas.
Defianz Racing, DCE

[Manas]

Hey all !

Corrections welcome http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

While Tuning an Engine : what exactly are we looking to tune : Is it the Air:Fuel Ratio , or the Ignition timing ? ar a combination of both along with changing of internal characteristics of the Engine : viz the cylinder and piston head configuration and geometry , Spark Plug positioning ?

I think the tuning aims at acheiving a non-peaky , flatter Power curve in the working rpm range. Does my interpretation require amendments ?

To what extent do these parameters influence the power curve ? which one influences it the most ?

Is it true that tuning an MPFI engine is more cumboresome than tuning a Carbureted one ?

I have been of the point of view that Dyno-testing comes into the picture only once the car has run a considerable amt of miles . ( ?? )

If intake and exhaust designs are finalised only after Dyno-testing, which ,as i have said(or think), comes after actual running of the car, .... in this case, how is the entire car finalised with the Intake ,and more importantly, the Exhaust absent ? ('cuz they will come in the pic. after dyno tests) !! ??

I believe, i am missing something drastically important here.

Please correct me where ever im wrong.

Which teams sets the working boundary for the other ?? The chasis for the exhaust ? or the vise-versa? I mean to ask, which of these is finalised first ? 'coz exhaust routing becomes painfully combersome after the rear chasis is in place.

I might sound pretty novice: blv me : i am. !

And do Performance Trends softwares really pose more problems than they solve ? I found them to have a pretty small Learning curve : so was going to use them .

Thanx.
\\//, Live Long and Prosper.
Manas.
Defianz Racing, DCE

[andrewd]

i can help you out about the exhaust

personally i believe it is a slight compromise between chassis and exhaust routing

in previous years during the design the exhaust is often routed within the chassis confines and the engine mounting is given preference

the biggest problem is the headers, trying to fit those in place rather than the tailpipe which takes alot less time http://fsae.com/groupee_common/emoticons/icon_wink.gif

[altendky]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>While Tuning an Engine : what exactly are we looking to tune : Is it the Air:Fuel Ratio , or the Ignition timing ? ar a combination of both, <HR></BLOCKQUOTE>

a combination of both.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>along with changing of internal characteristics of the Engine : viz the cylinder and piston head configuration and geometry , Spark Plug positioning ? <HR></BLOCKQUOTE>

i'm going to guess that you'll end up leaving these alone, at least this year. if you're just getting started, i would recommend building a reliable motor which can be read as don't modify your block/head/pistons etc...

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>I think the tuning aims at acheiving a non-peaky , flatter Power curve in the working rpm range. Does my interpretation require amendments ? <HR></BLOCKQUOTE>

know your relative ratios in your tranny and decide your philosophy of torque vs. hp (a whole other discussion, though i say hp CurvE is more valuable to look at than torque curve). between these you will know your working rpm. in that working rpm you want the highest power output you can get and the most predictable output (similar to what you said). of course, their is a trade off between the two.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>To what extent do these parameters influence the power curve ? which one influences it the most ? <HR></BLOCKQUOTE>

air/fuel controls fuel consumption and not leaning out the motor and burning it up. ignition timing will tune your power (many rev limiters control power via retard). of course, if you change any of the physical factors (intake/exhaust, etc..) EverythinG will change to some degree or other in your maps.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Is it true that tuning an MPFI engine is more cumboresome than tuning a Carbureted one ? <HR></BLOCKQUOTE>

how about this. efi allows you to control timing and fuel delivery dependent upon throttle position (or manifold pressure) and rpm (also modified by coolant temp, air temp, ambient pressure, and who knows what else). that's 5+ variable inputs to define each of the outputs. compare that with a carb which is mostly going to be tuned by the size of one or two jets.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>I have been of the point of view that Dyno-testing comes into the picture only once the car has run a considerable amt of miles . ( ?? ) <HR></BLOCKQUOTE>

do NOT put a new motor (or freshly rebuilt motor) directly on the dyno and run it under high load. there is a break in period, though if you don't have your motor tuned how will you run it to break it in? basically, low load tuning followed by low load break in followed by higher load tuning and breakin, etc...

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>If intake and exhaust designs are finalised only after Dyno-testing, which ,as i have said(or think), comes after actual running of the car, .... in this case, how is the entire car finalised with the Intake ,and more importantly, the Exhaust absent ? ('cuz they will come in the pic. after dyno tests) !! ?? <HR></BLOCKQUOTE>

as noted above, breaking and tuning are done on the dyno. this happens prior to running in the car. though, timing doesn't always work out great.

best of luck
-kyle