Advanced Tech Advanced tech discussion. Major rebuilds, engine theory, etc.
HIGH-END DISCUSSION ONLY - NOT FOR GENERAL TECH INFO

Why HP/TQ difference when using seat timing to duration at .050" lift

Thread Tools
 
Search this Thread
 
Old Feb 22, 2010 | 07:18 AM
  #1  
F6's Avatar
F6
Thread Starter
Registered User
 
Joined: Jan 2003
Posts: 165
From: Lengede
Why HP/TQ difference when using seat timing to duration at .050" lift

I’m using my engine analyzer and trying to find out what HP/TQ I might be getting when I’m finished with my engine update. SR and LE 210 AFR heads
I know these simulations are not going to give me the exact numbers, but I thought at least when using seat timing and then duration at .050" lift they would be about the same +- 2-3 HP.
Why do I have such a big discrepancy, although it fits at 4900-5400 rpm???

RPM…..seat timing……050”
2400……..375…………364…TQ
3400……..399…………379…TQ
4900……..525…………524…TQ
5400……..537…………540…TQ
6400……..604…………618…HP
6900……..593…………609…HP
Old Feb 22, 2010 | 05:29 PM
  #2  
96capricemgr's Avatar
Registered User
 
Joined: Feb 2004
Posts: 4,800
It is cheap inaccurate software that doesn't know the true complete lobe profile. Don't waste your time with such things.
Old Feb 23, 2010 | 05:09 AM
  #3  
F6's Avatar
F6
Thread Starter
Registered User
 
Joined: Jan 2003
Posts: 165
From: Lengede
You are right about the software not asking or knowing the exact lobe profile. I tried a 10 trial offer from EA 3.09 which is really not bad, but still there was a big discrepancy in numbers.
I recall someone on a different forum asking the same question but no one really knew a good answer.
I'll just take an average of the HP/TQ numbers and see how it compares to the real world dyno numbers.
Old Apr 3, 2010 | 02:13 PM
  #4  
rskrause's Avatar
Moderator
 
Joined: Dec 1969
Posts: 10,745
From: Buffalo, New York
Well, you can infer what assumptions the software makes, FWIW. If it shows more power using adv. duration it implies that the software is modeling a more aggresive lobe and vice versa. I am not a software engineer, but it seems like it shouldn't be very much more difficult to write the program to use at least the three commonly published durations (0.006, 0.050, and 0.200) for a better sim.

Rich
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Roadie
Parts For Sale
7
Feb 16, 2015 10:34 AM
PFYC
Supporting Vendor Group Purchases and Sales
0
Jan 23, 2015 01:13 PM
kandied91z
Midwest
0
Jan 23, 2015 11:14 AM
bossco
Automotive News / Industry / Future Vehicle Discussion
4
Nov 29, 2014 10:18 AM
siguy
Parts For Sale
3
Nov 27, 2014 10:07 AM




All times are GMT -5. The time now is 09:15 PM.