Is it better to power shift (not let go of the gas I think..) or to shift normally when drag racing. What are the pros and cons of both? Sorry if it sounds stupid, I did try to search, but didn't find anything.

 

I say do it normally, due to the fact that you can tear up the tranny faster. If you really want to full throttle shift, just purchase a Hondata s200, or s300. I think both units come with Full throttle shifting. Please correct me if I'm wrong.

 

Thanks, can anybody else chime in?

 

I FTS... I say go for it as long as you have a sprung hub and can acctually shift fast

 

just dont do it if youre making a lot of power on stock gears

 

Good topic. You got the definition right. I've heard it called "no lift shift", "ripstick" and some others that aren't worth mentioning. Downsides, power shift a high horsepower car with stock trans, axles, or driveshaft and axles w/ a set of gumballs and you'll most definitely leave some parts behind. Upside, when you pull it off(it takes practice) your car will take a 1200cc crotchrocket like its a scooter and it sounds like your goin through the gears on a automatic with a pneumatic shifter. Try liftin your foot off the gas just a little bit for starters and gradually work up to not lifting your foot off the gas. Be warned your gonna learn how to split and overhaul your trans doin this, same for axles and the like

 

yeah and if you're powershifting and you don't get it into gear all the way, you'll grind your synchro out.. haha a buddy did it on his 2nd gear

 

To practice power shifting you done need to go to red line. you can start our at any lower rpm until you get good.

4000 rpm is a good starting point, then 5000, 6000... You may also learn something about torque along the way. When you see how much the tires spin.


Modified by 1992Si at 10:47 PM 11/15/2007

 

Foot on the floor is the way to go. The column of air is not hitting the throttle blade when you lift so the air has some inertia to keep it moving. Just my physics 101 .02. The key is to make sure that you shift into the next gear while the clutch is disengaged.

 

With big power setups. The difference between granny shifting and powershifting can be as much as 8-9 tenths off your time.

 

Correct me if I'm wrong, but isn't it bad for the Clutch also???

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rota92 &raquo;</TD></TR><TR><TD CLASS="quote">did it all season, car LOVED it</TD></TR></TABLE>

Stock tranny, open diff and stock axles and pullin' 1.65 60's


missing 2nd gear in Vegas in the finals..missing out on the chance to earn a Wally.........Priceless

 

I have power shifted only 2 times (pushing clutch in, staying full throttle)

1st.pass we went 9.2@164, 2nd time we went 9.2@167, 3rd time before finally giving it more power for 3rd/4th went a 1.41 60ft and broke 2nd gear....

Prior to that we went 2 complete seasons and didn't break a trans...

We are using the Carbon Quarter Master clutch with hydraulic throw out bearing...no more slave cylinder in the way...

 

I'd rather NOT break trans. So I lift to shift. I use to do it all the time until I sterted breaking all the time. I have been just as fast lifting.

 

so it is poss. without the the setup in hondata. i have an older unit that didnt have it. i was under the impression there was some computer way of not letting it happen, hence the option from hondata.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jeffy &raquo;</TD></TR><TR><TD CLASS="quote">so it is poss. without the the setup in hondata. i have an older unit that didnt have it. i was under the impression there was some computer way of not letting it happen, hence the option from hondata. </TD></TR></TABLE>

hondata has a limiter you can set when you FTS. I think it has to use the clutch switch which mine is bypassed so it would prolly cause me headache.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nonvtecallmotor &raquo;</TD></TR><TR><TD CLASS="quote">I'd rather NOT break trans. So I lift to shift. I use to do it all the time until I sterted breaking all the time. I have been just as fast lifting.</TD></TR></TABLE>

Agreed. I actually did some testing on this subject and went exactly the same E.T's shifting both ways. I never broke anything while powershifting but, I did miss 2nd gear a few times where as "Lift to shift" I'm dead on every pass.

Phil

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Antilag &raquo;</TD></TR><TR><TD CLASS="quote">With big power setups. The difference between granny shifting and powershifting can be as much as 8-9 tenths off your time.</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hondaguyef &raquo;</TD></TR><TR><TD CLASS="quote">Agreed. I actually did some testing on this subject and went exactly the same E.T's shifting both ways.</TD></TR></TABLE>

So which is it? 8-9 tenths or no difference?

My datalogs show that I lose boost (obviously) when the throttle plate closes and the BOV opens, so this takes time to recoup. I would think that not lifting would be beneficial, but I'd hate to miss. I guess it just takes practice. The tilton valve should reduce the shock I'm sure.

 

thanks guys

 

I used to do powershifting and It shaved about 2-3 tenths. However, 3rd and 4th synchros gone bad. It will cause more damage if you don't do it right.

 

I did break 2nd gear synchros all the time, untill we wouldnt install the switch under the clutch (taken from brake pedal sensor) conected to AEM (it drops RPMs when Im pressing the clutch to 5000 so I can get into the gear) - and I forgot about the lag
Plus sequental shifter exclude missshifts... also dont forget stronger clutch to avoid the sliping My suggestions - very nice setup!


Modified by borislunov at 12:41 PM 11/26/2007