i need some help with the math!

Tim Dugan

New member
OK i might as well tell the world I sold the corrado and i am on my way on friday to purchas a new car! Which i am very excited about i know there are people out there that can help me with the build multiplier. The car is a 2000 BMW 323 which i will be running in ITS for the time being. So here is the major question i have what is the expected build WHP and how do i get that number? I know you guys are really good with numbers and oh ya i need to get the car classed for there is no 323ic in the GCR so all the help i can get would be great! Thanks for your support through this rough time LOL! Hope to see everybody soon! :happy204:
 
Hmmm, is this the 323i which really has a 2.5L 24V inline six? If so it might be classed in ITR. I don't have access to a GCR right now.

R
 
e46 323 is listed in S at 3000 pounds, but not in "c" form - which I think means it's a coupe...?

Sounds like a VERY cool option, Tim!

K
 
the autotechnic guys do some damage in ITS with their 323is sedan. If all things are equal, if should not matter if it's a coupe or sedan. Write to the CRB - good luck!
 
Yes the "C" stands for coupe and the auto technic cars are built to the max! Mine will be a little slower at first but hopefully within a couple of years we can get the car twisted just right and if something happens to ITS the car can be converted to ITR with very little work. So back to my question how do i find a realistic build up % on the motor? The motor is stock with a shark programing so just trying to figure out what is a realistic WHP for the car and how much its gonna cost to get there? I know the answer to that open check book and start with adding a lot of zeros! LOL my goal is to keep up with the RX8 this year and maybe even beat him. (sinister laugh)
 
I don't know how much hp you can make out of the motor, but if it is going to race competitively in ITS it'll need to generate north of 185 whp at that weight. And well north is what I'm thinking, 195-205 wheel hp at 3000 pounds.

I have no idea of the BMW engine can generate that sort of power. Certainly it seems the unrestricted BMW E36 325s of the 2002-2005 era were making that sort of power and more, but I don't know how that engine compares to yours.

Good luck with it, I'd love to see it out on track.
 
Math forthcoming....

2000 BMW 323 Ci

2.5L hp I6
chp 170 @ 5500 RPM
ctorque 181 @ 3500 RPM
Bore X Stroke 3.31 X 2.95
Compression Ratio 10.5:1

https://ams.scca.com/netForum/eweb/documenttransfer.aspx?doc=scca_postings/filecabinet/Advisory%20Committee%20Addendum-%20IT%20Process.pdf

170 * 1.25 (IT gains) * 0.82 (driveline loss RWD) = 174.25 whp * 12.9 lbs/hp (ITS multipler) = 2248 w/o adders or 2250

Do you have excessively large brakes? It's a BMW, I would assume so, +100 (in your face!)... so 2350.
Could there be a torque adder? maybe, if so then add another +100 (in your face... maybe)... so 2450

no way.

Let's try the other way around...

3000 - 100 = 2900 / 12.9 lbs/hp = 225 whp...
225 whp / 0.82 = 274 chp

OR

3000 - 200 = 2800 / 12.9 lbs/hp = 217 whp...
217 whp / 0.82 = 265 chp

Either I forgot to add something or you need to lots of luck ( I mean $).

Confirmed that the 99-00 323is/i seems like the same car as your 323 Ci.
 
Last edited:
170 * 1.25 (IT gains) * 0.82 (driveline loss RWD) = 174.25 whp * 12.9 lbs/hp (ITS multipler) = 2248 w/o adders or 2250

Do you have excessively large brakes? It's a BMW, I would assume so, +100 (in your face!)... so 2350.
Could there be a torque adder? maybe, if so then add another +100 (in your face... maybe)... so 2450


IIRC the process weight is on crank hp, so you don't include the 0.82

so... maybe:

170 * 1.30 (BMW IT gains) = 221 * 12.9 lbs/hp (ITS multipler) = 2850 + 50 brakes + 50 torques + 50 wishbones? = 3000

:shrug:
 
Tim- when "converted" to ITR what car model does it become? How much needs to be swapped? I only ask as I know this is your ultimate goal.

Raymond
 
1. Y'all are making this harder than it need to be, actually doing math. Ron's guesses are about as good as one is going to get if the question is about how much power is going to be necessary to get it in the competitive ballpark.

2. The car is listed in S - not in R and not in both. There's no such thing as upgrading to a class above any given car's spec line.

K
 
The cars here have to make AT LEAST 200whp. I've said it before...I have seen no dyno sheets but at the same weight as our ITR S2000 in it's debut and shake down, they were able to pull out and pass at WGI and we had 205whp at the time.

The 'upgrade' being spoken of is probably a 2.5, 2.8 or 3.0 swap.
 
The guy hangs of High Tension Power Poles in a Blizzard/Hurricane, you pick the natural disaster, So that we can quickly get back on line and update our Stuff. And he does it 18 hours on 6 off for weeks on end after the disaster, while living in a hotel room or the front seat of a line truck.

Its taken you this long to figure out hes crazy. We have all known it for years.

Tim have you recieved the call form OK yet? It might be a bit too far.
 
well as dan has stated yes im crazy and loving it!!!! I do most of my work with little to no sleep oh and we all like to drink so that takes time also! LOL but back to my question im just wondering what it takes to be to be at the pointy end of the ITS field? I know i did well with the corrado in 4 races qualifing 1st at the narrcoffs at lime rock but the car i am buying is expected to produce 170 plus or minus WHP. I wont know how it will produce until we get her home and put it through its paces but i know it will do well! @ raymond i do know i have the parts to make it an ITR car the parts are in the daily driver BMW. Hope to see everybody soon at the race track!!! Thanks to everybody that did the math for me i think im on the right track with the car oh and yes i was a little crazy to build the corrado but damn it was a fast car! and it sounded cool!!!!
 
IIRC the process weight is on crank hp, so you don't include the 0.82

so... maybe:

170 * 1.30 (BMW IT gains) = 221 * 12.9 lbs/hp (ITS multipler) = 2850 + 50 brakes + 50 torques + 50 wishbones? = 3000

:shrug:

Thanks Glenn, I think you got, except I don't think BMW's come with DW suspensions. Perhaps 50 adder for brakes and 100 for torque. By those numbers Tim needs to put down ~181-2 whp to make process power. Like Andy said, in full 10/10th mode, they probably make MUCH MORE as witnessed repeatedly.
 
Tim,
The electronics will kill you..... I broke down or had dumb issues... De-activating the abs and DSC will be a massive problem... Stand alone is the only way....... However the e46 325 ITR model can use the stock ECU a lot easier... M52tu= trouble .... I have a garage full of them... Giving a go with the 328 now.. .... If ITR is what you want STOP what you are doing and just go buy an E36 NOW! That will save you $20k.... Not kidding!

Greg
 
Back
Top