Texas Mile

Thread Tools
 
Search this Thread
 
Old Sep 19, 2012 | 09:08 PM
  #1  
ZDan's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Sep 2011
Posts: 682
Likes: 4
From: Pawtucket, RI
Texas Mile

Anyone else going?

I'll be there

The car did just over 129mph in the 1/4, hoping to do 175mph or better in the mile.

We shall see...

I'd be interested to hear if anyone has any data acq from standing-mile runs, I'm trying to model the car's performance but am unsure of tire slip and tire growth, so I'm mostly guessing there. Very critical factors relating to gearing!
Reply
Old Sep 25, 2012 | 11:53 PM
  #2  
marcrx5's Avatar
Junior Member
 
Joined: Sep 2012
Posts: 25
Likes: 0
From: CO
While tire slip and tire growth are critical for gearing, aero should be the dominant factor in the entire equation. Do you have good values for aero drag?
Reply
Old Sep 26, 2012 | 10:36 AM
  #3  
ZDan's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Sep 2011
Posts: 682
Likes: 4
From: Pawtucket, RI
Originally Posted by marcrx5
While tire slip and tire growth are critical for gearing, aero should be the dominant factor in the entire equation. Do you have good values for aero drag?
I'm conservatively (I think) assuming a Cd of .33, frontal area of 20 square feet. Hopefully with skinnyish tires (225/245), all front radiator/brake openings blocked off, taped gaps between lights/hood/fenders, removed mirrors and windshield wipers, the Cd will be .30 or less. But even a small sidewind will give more drag...

I'm calibrating the model to a known 196mph run for a similar V8 FD with ~20% more power. Based on that, I should be in the ~184mph range. Which agrees perfectly with the model I'd already come up with, excellent!

For gearing, the *worst* would be to have more than expected tire slip, less than expected tire growth, and higher than expected speed, which could require a shift to 6th, which is to be avoided at all costs!

With my worst-case (I think) slip of just over 5% at speed, and zero tire growth, my chosen 25.7" tire size should be good for 188mph in 5th gear at 7000rpm, which should be PLENTY.

At the other extreme, with significant tire growth and reduced slip, 25.7" tires could have me as low as ~6300rpm at 180mph, but that's right at peak power anyway.

Spreadsheet model indicates little/no speed penalty for erring on the tall-geared side.
Reply
Old Oct 7, 2012 | 05:37 PM
  #4  
se7ensti's Avatar
Junior Member
 
Joined: Dec 2010
Posts: 15
Likes: 1
From: Lake Charles, Louisiana
I would love to run the Texas Mile one day, but I should probably take it down the 1/4 first, seeing how I just finished the swap only a month or two ago.
Reply
Old Oct 27, 2012 | 09:48 PM
  #5  
ZDan's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Sep 2011
Posts: 682
Likes: 4
From: Pawtucket, RI
Originally Posted by ZDan
I'm calibrating the model to a known 196mph run for a similar V8 FD with ~20% more power. Based on that, I should be in the ~184mph range. Which agrees perfectly with the model I'd already come up with, excellent! .
Ran 183.8 mph in the mile today. Off by only 0.2 mph!
Reply
Old Oct 28, 2012 | 07:27 AM
  #6  
DeaconBlue's Avatar
Living on the North Coast
iTrader: (31)
 
Joined: Mar 2009
Posts: 600
Likes: 7
From: Avon Lake
Very cool! How was the event overall?
Reply
Old Oct 28, 2012 | 10:59 PM
  #7  
ZDan's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Sep 2011
Posts: 682
Likes: 4
From: Pawtucket, RI
184.8mph this AM. Yee-haw!

Great event More later, sleep now...
Reply
Old Oct 29, 2012 | 11:16 AM
  #8  
Ruler_Mark's Avatar
I can't see my car **(
iTrader: (16)
 
Joined: Apr 2010
Posts: 1,600
Likes: 8
From: Central FL
Whats your powerplant?
Reply
Old Oct 29, 2012 | 12:26 PM
  #9  
ZDan's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Sep 2011
Posts: 682
Likes: 4
From: Pawtucket, RI
LS2 with shaved L92 heads, LS3 intake and injectors, 222/230 .597" cam. Pretty mild build, really. It's a street car, with p/s, a/c, full interior. I drove it down from Rhode Island
Reply
Old Oct 29, 2012 | 01:29 PM
  #10  
djseven's Avatar
Eh
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (56)
 
Joined: Aug 2002
Posts: 6,553
Likes: 344
From: Nashville, TN
Originally Posted by ZDan
LS2 with shaved L92 heads, LS3 intake and injectors, 222/230 .597" cam. Pretty mild build, really. It's a street car, with p/s, a/c, full interior. I drove it down from Rhode Island
Reply
Old Nov 6, 2012 | 06:08 PM
  #11  
gnx7's Avatar
Rotary Freak
Tenured Member: 25 Years
Liked
iTrader: (10)
 
Joined: Mar 2001
Posts: 2,090
Likes: 26
From: San Francisco, CA
Nice speed for a mild engine swap. ZR1 Corvettes aren't running that fast

That motor I'm guessing probably puts down around 450rwhp depending upon which dyno you use.
Reply
Old Nov 7, 2012 | 07:39 PM
  #12  
ZDan's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Sep 2011
Posts: 682
Likes: 4
From: Pawtucket, RI
Yup, stock ZR1s were reportedly running 178 - 183 at the Texas Mile this event.

Name:  BobbyHMAFonlytune.jpg
Views: 28
Size:  83.3 KB
Might be optimistic!
129.2mph 1/4-mile speed at 2400' density altitude suggests 515 (raw) to 555 (corrected for d.a.) flywheel hp.

Similar trap speed and mile speed vs. ZR1 suggests ~540+ hp flywheel.

In any case, it's a LOT more than I'd have expected for the build

Last edited by ZDan; Nov 7, 2012 at 07:42 PM.
Reply
Old Nov 10, 2012 | 08:12 PM
  #13  
85turbo12a's Avatar
nerd
 
Joined: Aug 2009
Posts: 175
Likes: 0
From: Lakeland Florida
nice man, i know we got off to a bad start in the other thread but trust me i respect others builds, and thats a nice power curve, those LS engines are un-arguably amazing for their size and weight, AND physical size.
looks like you got a nice combo of parts working well with each other, now lets turbocharge it and make it silly
Reply
Old Nov 11, 2012 | 06:05 PM
  #14  
ZDan's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Sep 2011
Posts: 682
Likes: 4
From: Pawtucket, RI
Originally Posted by 85turbo12a
nice man, i know we got off to a bad start in the other thread but trust me i respect others builds, and thats a nice power curve, those LS engines are un-arguably amazing for their size and weight, AND physical size.
looks like you got a nice combo of parts working well with each other, now lets turbocharge it and make it silly
Get thee behind me, Satan! I gots to say, the idea of 200+ in the mile on barely any boost at all (even with stabilizing but drag-adding rear downforce) is tempting...
Reply
Old Nov 11, 2012 | 07:54 PM
  #15  
85turbo12a's Avatar
nerd
 
Joined: Aug 2009
Posts: 175
Likes: 0
From: Lakeland Florida
dont fight it...just relax and let it happen
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Skeese
Adaptronic Engine Mgmt - AUS
65
Mar 28, 2017 03:30 PM
NCross
2nd Generation Specific (1986-1992)
9
Sep 3, 2015 03:42 PM
fastrx7man
3rd Generation Specific (1993-2002)
33
Sep 2, 2015 09:42 PM




All times are GMT -5. The time now is 12:21 AM.