SwedeSpeed - Volvo Performance Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
530 Posts
Discussion Starter · #1 ·
I know stock 6200 rpm is best place to shift but how about when modded or Re-tuned Ei- Bsr chip? Do the shift points change?
 

·
Registered
Joined
·
63,543 Posts
Re: What is the best shift point on a Chiped R? (zigger)

Same
 

·
Registered
Joined
·
6,037 Posts
Re: What is the best shift point on a Chiped R? (StaggRLee)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>StaggRLee</b> »</i></TD></TR><TR><TD CLASS="quote">He has a GT. Does it matter?</TD></TR></TABLE>depends, does he have a GTR badge?
 

·
Registered
Joined
·
3,846 Posts
Re: What is the best shift point on a Chiped R? (R_Rated)

Maybe. That adds what in HP/bragging rights?<p>Should probably be shifting at ~9K then I suppose.
 

·
Registered
Joined
·
3,846 Posts
Re: (R_Rated)

<IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/tongue.gif" BORDER="0"> <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/biggrin.gif" BORDER="0">
 

·
Registered
Joined
·
1,450 Posts
Re: (StaggRLee)

please see below for guidance as to when vtec kicks in<br> <IMG SRC="http://images.google.com/images?q=tbn:IGQ0e8ffeRip-M:http://www.westcoast6s.com/photos/albums/userpics/10001/vtec.JPG" BORDER="0">
 

·
Premium Member
Joined
·
3,121 Posts
Re: What is the best shift point on a Chiped R? (zigger)

There are two ways to do this.<p>First, see if you can get a dyno graph from BSR that plots horsepower and torque. The rule of thumb I've driven by is that you want to shift at a slightly higher rpm from where the torque begins to fall off. On a stock R, torque drops off at about 5500, so you want to shift just slightly beyond that. You'll have to look at BSR's graph in order to know. <p>The second way is to go to the drag strip and compare different runs using different shift points. Since you've got a GT, stallcharge it to 2500 RPM every single time, that way you remove your launch as a variable. On one run, shift at red line. On another run, shift at 5500. On another, shift at 6300. See which gives you faster results.<p>Also, length of track can have a factor. For instance, when I race my car at the 1/8 drag strip, I shift at 5500 in 1st, 6300 in 2nd, and then I redline it in 3rd. The reason for this is if I shifted at 5500 in each gear, I'd be forced to shift from 3rd to 4th before the finish line . . . and every time you shift, you lose time and momentum. Now, in the 1/4, my fastest times were had shifting just shy of 6000 in every gear. But in order to make my 1/8 times what they should be, I had to play around with shift points in order to make the finish without having to shift into 4th.<p>By the way, you may want to make one run just leaving your car in automatic mode . . . I've found that sometimes the vehicle accelerates quicker if you just leave it alone. Remember: a higher rpm shift point does not equal faster times.
 

·
Registered
Joined
·
10,097 Posts
Re: What is the best shift point on a Chiped R? (R Salesman)

That's [email protected] scenario? <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/rolleyes.gif" BORDER="0"> <p> <IMG NAME="icon" SRC="http://********************/smile/emthup.gif" BORDER="0">
 

·
Registered
Joined
·
2,052 Posts
Re: What is the best shift point on a Chiped R? (zigger)

The best analytical method is to plot rear wheel torque as a function of vehicle speed for each gear. You need to have the engine torque curve as well as the trans gear ratios and the diff ratio. <p>The plot will show that for a given gear, rear wheel torque peaks at a certain speed, and then falls off. At some point, the wheel torque in a given gear falls below the torque available in the next gear. The optimum shift point is the point where the two curves cross.<p>If you do this, you will find two things...<p>1. The optimum shift point is slightly different for every gear (generally higher rpm in lower gears)<br>2. The optimum shift rpm is generally a few hundred rpm above the peak <I>horsepower</I> rpm <p>The idea is to maximize the area under the horsepower curve for a given gear. Intuitively, you can see that you must shift after you pass through the peak to do this.<p>Sometimes the optimum shift point from a performance perspective is higher than the limits imposed by valvetrain, rev limiter, etc. <p>I haven't done the analysis for the R, but I did it for my hypothetically-chipped Audi. The chip brought the horsepower up, but peak power occurred at a lower rpm. Optimum chipped shift points moved down 3 - 400 rpm from the ideal stock shift points.<BR><BR>
<i>Modified by Dyno at 3:35 PM 5-10-2006</i>
 

·
Registered
Joined
·
1,659 Posts
Re: What is the best shift point on a Chiped R? (Dyno)

I have a 2004 R with the BSR PPC. I find 9 out of 10 times the car has better shift points in the "auto" mode than when I do the shifting myself. The reason for this is the time it takes the tranny to recognize that you have engaged the next gear. It takes almost twice as long for the shift to happen in manual than in auto. Quirky I know! But it is a Volvo. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/wink.gif" BORDER="0">
 
1 - 12 of 12 Posts
Top