Any way to convert 2nd gear hp to 3rd gear hp? - LS1TECH

Log In 


Dynamometer Results & Comparisons Dyno Records | Dyno Discussion | Dyno Wars

Any way to convert 2nd gear hp to 3rd gear hp?

Reply
 
Thread Tools Search this Thread
Old 05-02-2005, 06:32 AM   #1
TECH Addict
Thread Starter
iTrader: (18)
 
tdrumm's Avatar
 
Join Date: Oct 2003
Location: Northeast, NJ
Posts: 2,373
Default Any way to convert 2nd gear hp to 3rd gear hp?

I dynoed my truck this weekend, the first pull was done in 3rd gear, but we hit the factory speed limit at 4000 rpm. The rest of the pulls were done in 2nd gear up to 5900 rpm, and the curves are noticeably lower than the 3rd gear curve. Is there a way to convert the 2nd gear numbers to what they would have been in 3rd gear?

Thanks
tdrumm is offline   Reply With Quote
Old 05-02-2005, 12:18 PM   #2
LS1TECH Sponsor
iTrader: (1)
 
foff667's Avatar
 
Join Date: Jul 2003
Location: Clermont, FL
Posts: 7,987
Default

generally 5-15hp/tq less when done in 2nd gear...no set way that i know of to convert it though
foff667 is offline   Reply With Quote
Old 05-02-2005, 01:49 PM   #3
Banned
iTrader: (45)
 
Join Date: Aug 2003
Location: NC
Posts: 2,557
Default

Check the stockdyno thread, there are some graphs that will help estimate.
lsx24 is offline   Reply With Quote
Old 05-02-2005, 02:07 PM   #4
TECH Addict
Thread Starter
iTrader: (18)
 
tdrumm's Avatar
 
Join Date: Oct 2003
Location: Northeast, NJ
Posts: 2,373
Default

On my dyno print out, it looks like all the 2nd gear pulls are about 15-20 hp and tq less than the portion of the 3rd gear pull that was done. Is it safe to assume that would continue to hold true above 4000 rpm? I was hoping there would be a mathematical way to convert it so that when I dyno after my cam swap with the speed limiter removed, I'd have a true before and after comparison.
tdrumm is offline   Reply With Quote
Old 05-02-2005, 02:09 PM   #5
LS1TECH Sponsor
iTrader: (1)
 
foff667's Avatar
 
Join Date: Jul 2003
Location: Clermont, FL
Posts: 7,987
Default

Quote:
Originally Posted by tdrumm
On my dyno print out, it looks like all the 2nd gear pulls are about 15-20 hp and tq less than the portion of the 3rd gear pull that was done. Is it safe to assume that would continue to hold true above 4000 rpm? I was hoping there would be a mathematical way to convert it so that when I dyno after my cam swap with the speed limiter removed, I'd have a true before and after comparison.
just have them dyno it once in 2nd gear after your cam swap if you really need a before/after #
foff667 is offline   Reply With Quote
Old 05-02-2005, 02:14 PM   #6
Banned
iTrader: (45)
 
Join Date: Aug 2003
Location: NC
Posts: 2,557
Default

Quote:
Originally Posted by tdrumm
On my dyno print out, it looks like all the 2nd gear pulls are about 15-20 hp and tq less than the portion of the 3rd gear pull that was done. Is it safe to assume that would continue to hold true above 4000 rpm? I was hoping there would be a mathematical way to convert it so that when I dyno after my cam swap with the speed limiter removed, I'd have a true before and after comparison.
Did you check out my stock graph? There were two lines one for 2nd another for 3rd. Peak hp started to approach the value in 3rd.
lsx24 is offline   Reply With Quote
Old 05-02-2005, 02:36 PM   #7
TECH Addict
Thread Starter
iTrader: (18)
 
tdrumm's Avatar
 
Join Date: Oct 2003
Location: Northeast, NJ
Posts: 2,373
Default

Quote:
Originally Posted by 98t56TA
Did you check out my stock graph? There were two lines one for 2nd another for 3rd. Peak hp started to approach the value in 3rd.
Yep, I am guessing that the green run was the second gear pull. I see that 2nd did start to approach 3rd, but I can't read the number. It looks like 3rd you hit 298 and 2nd was around 285???
tdrumm is offline   Reply With Quote
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
TH400 not staying in gear Phantom383 Automatic Transmission 0 08-08-2015 02:45 PM
Clutch, Master or Slave? ADM Manual Transmission 0 01-05-2015 08:11 AM
My 347ci Dyno Results, Tony Mamo spec'd and Patrick G tuned turbo Dynamometer Results & Comparisons 17 11-22-2011 07:31 PM
4L80e slipping on Dyno.... 30th t/a Automatic Transmission 11 12-02-2008 07:23 PM
HPT A4 Shift question with 3:73 Gears ,Rpm=Mph? Pro Mouse PCM Diagnostics & Tuning 6 07-22-2005 04:47 PM


Tags
2nd, 3rd, convert, dyno, gear, horsepower, hp, pulls, run

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off



All times are GMT -5. The time now is 10:15 PM.