Big Picture of IT - Share Your Opinions

[Andy Bettencourt]

There's not enough information in your example, some info you have that would help illuminate the example:

1) Motor data:

a) displacement ( and bore/stroke )
b) oe hp at what rpm
c) valve sizes and number per
d) does it have cheap cast oe manifold, is it a narrow v6 or have a dual length intake manifold
e) how many gear ratios, what are they?

2) Chassis data:

a) front or rear wheel drive?
b) Struts or A arm front
c) solid axle, trailing arm, or multi-link rear
d) Brake size
e) how aero is the body, is it a brick, or does it have a round tail end that sheds vortices (ala early TT/350Z)

This should mostly be avalible on the VTS sheet.

Why do you need that data James? That data was used in the caluclation of the 'process weight of 2300lbs'. Assume that all the ganularity of the process has been utilized. If you are asking us to consider aero, the amount of gears, the construction of the intake manifold, the size of the valves...we don't.

[Z3_GoCar]

Why do you need that data James? That data was used in the caluclation of the 'process weight of 2300lbs'. Assume that all the ganularity of the process has been utilized. If you are asking us to consider aero, the amount of gears, the construction of the intake manifold, the size of the valves...we don't.

I'd be looking for a reason it'd have a larger gain than normal. Is there a chance that a cam swap was performed? How about intake manifold swaps? Is that another possibility? Gearing can really help too, see the discussion on the ITB Metro for sale thread, where at one time a factory aftermarket race ratio set was avalible. Maybe the owner felt the car was such an outsider, he took matters into his own hands to equalize it in his own less than kosher way. You need to find out if the single case was an outlier, or the norm.

[lateapex911]

I'd be looking for a reason it'd have a larger gain than normal. Is there a chance that a cam swap was performed?

chance? Sure, because the car wasn't torn down, the only thing we KNOW, is that we don't KNOW what was in the engine.

How about intake manifold swaps? Is that another possibility?

Sure, see above.

Gearing can really help too, see the discussion on the ITB Metro for sale thread, where at one time a factory aftermarket race ratio set was avalible. Maybe the owner felt the car was such an outsider, he took matters into his own hands to equalize it in his own less than kosher way. You need to find out if the single case was an outlier, or the norm.

James, you have a point. But, how are we supposed to do that? None of the racers can! Well, some of the racers are SURE the other guy is cheating, and some of the racers are SURE the cars just classed wrong....

Do you want us to:
1- Assume he's cheating, and ignore it?
2- Assume he's legal, look at the lap times and just add a hundred pounds.

I'm guessing most will choose "3".

So, how do you get the data, and how do you trust it? What can you apply consistently as a method for such data acceptance?

Simple answers are few and far between.........

[Z3_GoCar]

chance? Sure, because the car wasn't torn down, the only thing we KNOW, is that we don't KNOW what was in the engine.

Sure, see above.


James, you have a point. But, how are we supposed to do that? None of the racers can! Well, some of the racers are SURE the other guy is cheating, and some of the racers are SURE the cars just classed wrong....

Do you want us to:
1- Assume he's cheating, and ignore it?
2- Assume he's legal, look at the lap times and just add a hundred pounds.

I'm guessing most will choose "3".

So, how do you get the data, and how do you trust it? What can you apply consistently as a method for such data acceptance?

Simple answers are few and far between.........

Jake, I agree this isn't a simple problem with simple answers that can be typed in one post. That's why you, Andy, Josh, Kirk, et. al

But, I think we all agree the assumptions need to be minimized. Isn't that what the process v 2.0 is about?