Your guide to drag strip success w/pics.

outofstep

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#1
Be warned, this post may offend.

Feel free to skip the rant section and go directly to the how to.

RANT said:
I’m going to address a very serious problem in the Supra community; the quarter mile. Whenever supra owners go to the track, they suddenly become half retarded monkeys that can no longer figure out how to drive. I maintain that Supra owners are the worst drivers of all automotive enthusiasts. And what happens when a Supra owner does shitty at the track? They blame everything but themselves. I’ve got news for you jackass Vettes, Cobras, RX7s, 300ZXs, none of them seem to have issues launching their independent rear suspensioned car. Hell, damn front wheel drive Hondas launch better than most supra owners, and they bitch about it less! An IRS is not an excuse. Many domestics have hundreds of pounds on our cars, yet they run faster with less horsepower. Weight is not an excuse. Its your own damn fault for thinking you could hook by just dumping the clutch on a dropped car (with lots of negative camber) rolling on small side walled 18s with street tires that you did a burn out on.

You don’t need 600 horsepower to run 11s. An other car in the world would be DEEP in the 10s with that much power. Hell, it should only take you mid 300s to run twelves. The next time someone posted about how they ran a 14@110 mph, I was going to drive to their house and punch them in the neck. So I had to make this thread. I’m sorry, but it’s fucking embarrassing when at the national meets our cars are running 13s and 14s. If you wonder why our cars get no respect, it’s because you monkeys make sure no one is afraid to race us. My stinking bolt on Integra GSR would eat most of the BPU MK3s on this board alive at the track. That’s just sad as hell because that car is slow as shit.

If I offended you, good. Maybe it will motivate you to prep your car. Take this criticism and use it to fuel your rage. Turn that rage into making your car perform. The dark side isn’t that bad.


Concepts:
When you launch your car from a stop there are two main things going on. Transfer of weight from the front to the rear and then hooking. If you want a better launch, you need to optimize both of these.




Manual Transmission specific section:

Working the Clutch:
There simply is no excuse for the “bog” or “sit and spin” if you’ve driven your manual car for more than a month.

Every single day you can get tons of practice launching. Every single stop light, every single stop sign. I’m not telling you to stage like you’re at the track and try and burn rubber like a madman. I am telling you to figure out what your clutch setup likes. You can launch hard and still be perfectly legal on the street. You drive your car, so get to know how it drives.

Most of the time, launching at the track is just like regular driving. The speed that you release the clutch pedal during normal driving, is the same speed you release it while launching at the track. Thinking you have to rev and then just dump the clutch is why people sit and spin or bog. Bring your revs up high, and release the clutch the same speed as if you were easing away from a stop light. This works with most clutch setups. But like I said earlier, get to know how your car launches. You should know how to work your clutch for good launches before you ever goto the track.

Boost from the line:
Boosted Manual cars have a big disadvantage at the track. No boost from the line. This is easy to cure. It’s called a two-step, or rev limiter. You step on the gas and the two-step will artificially limit your revs at a lower level (you usually set this at your launch rpm. You should know your launch rpm because you have practiced and know what works). This loads the engine and you will get boost. Launch and shut off the two step. There you go, manual car with boost from the line. It can mean the difference between starting out with over a hundred or more horsepower from a turbo that’s actually spooled up.

If you are serious about dragging with a manual, you need to get a rev limiter/two step.

You can get it running with the MSD PN 6215, Dis-4. It will also require 2 of the PN 8912 Adapters. Theres another one that works but I cant remeber it right now. I'll put the info in when I remeber it.

Here's what a 2step sounds/looks like if you have never heard/seen one. It basicly just sounds like hitting the rev limiter like normal. This is duane building boost at the line and whuppin a mk4. http://media.putfile.com/11supra


Power shifting
WARNING – This can fuck up your tranny with a quickness. But if you just need that extra 0.1-0.3 you can do it.

Power shifting is when you keep your foot planted on the gas and barely, barely, barely, touch the clutch pedal just to release the clutch, then jam it into the next gear with your foot already off the clutch pedal. It is very fast and will keep your turbo spooled. But it’s rough as shit on the transmission.

I personally don’t recommend it because to me a grenaded tranny isn’t worth a time difference that could be attributed to standard deviation anyways.


Automatic transmission specific section
Stall, Stall, Stall. Get a high stall torque converter. This is standard practice for EVERYONE IN THE WORLD but us it seems like. I can count on one hand the auto guys on this forum that have a stall. That’s sad as hell. For 200 bucks people cant be bothered to get something that can potential drop their quarter mile time by almost a full second.
There are more places that can do our stalls, but this is all I can remember right now.

www.phoenixhardparts.com
http://www.hughesperformance.com/
www.soundperformance.com
www.levelten.com
http://www.ipttrans.com/toyotaauto.shtml

Phoenix Hard Parts and Hughes can rework your stocker to a high stall unit for ~200 bucks. The performance vs price for a stall is better than nitrous.

Just go get a stinking stall already. Launching with tons of boost from the line is heaven. Laugh at all your manual friends as you leave them in the dust.


Suspension set up:

Sway bar / End links:
I keep saying this but people aren’t listening. When at the track, disconnect the front sway bars. This goes back to the original concept that I talked about earlier. Transfer of weight to the rear of the vehicle. With the front sway bar disconnected it allows freer movement of the front suspension. Lets weight shift occur easier. Disconnecting the front sway bar is de facto standard in pretty much most auto enthusiast groups aside from the moron import crowd.

Don’t drive to the track with them disconnected though. That wont be fun. Also before you do this at the track, disconnect them once or twice and drive around your neighborhood to get a feel for what its like with them off. You don’t want to get squirrelly down the track your first time with them off. Know how it drives.

With adjustable end links it’s makes unattaching the front bar a breeze. Just disconnect the lower tie on the tie bar. It also allows you to adjust your rear sway bar to fine tune your launch. There are one or two places that sell them I think. Or you can just make your own. I made my own as seen below:



Camber:
If you dropped your car, you now more than likely have negative camber. When you launch an IRS car, the camber moves to the negative. If you are already there, launching just makes your tires have a small little contact patch. This is a big reason why you dropped folks launch so shitty. Yeah your JDM dorifto million degrees of negative camber crap looks cool (to you), but it sucks for launching. Dial in a degree or two of positive camber before you go to the track. When you launch you ideally want zero camber, a flat contact patch. So if you are just a degree or two positive before you launch, when it squats you zero out. Perfect.
Where do you adjust it? Right here. See how easy it was to find it?


When adjusting the camber you also have to adjust the toe in to go along with it. Here's how to adjust both.



Trailing arms:
These are actually one of the very few weak links on our cars. The trailing arms bend pretty easily. Bent trailing arms = wheel hop. Not good. Three places sell replacement trailing arms. Carbonfiber FX, Suprasport, and A1 Racing. Or you can just take them to your local muffler shop and have the dude there weld on additional bracing for like 20 bucks. The A1 Racing trailing arms are great because they are adjustable. Preload and launch tuning baby.

Make sure that your trailing arms are squared away before you goto the track.


www.suprasport.com
www.carbonfibrefx.com
www.a1racing.com

Shocks/springs/coilovers
This is really something you just need to adjust and test for yourself. For some people hard front soft rear works better for them, for others vice versa. There are just too many different combos to tell you exactly what to do. I will tell you not to go full hard all around. It goes back to the original concept. You want weight to be able to shift to the back, then you want to hook.

Try starting out with the front abit harder than the rear. Then work from there. If you mess with the ride height, make sure you adjust the camber.


Rims and Tires
Sorry, but those low profile 17s,18,19s just aint gonna cut it.

The second part of the concept is hooking. Without decent tires, the best suspension in the world won’t mean crap. If you are serious about dragging, you need to go back to 16s or ideally 15s. You just cant get good drag tires in 17+.

Spend the 300 bucks on some nice fat quality drag radials or slicks. Only run them at the track. If this means buying an extra set of rims, then so be it. Some 235 slicks will hook better than some 315 street tires. So just drop the coin.

Nice big sidewalls are what you want. This allows the tire to flex and hook. Check the drag racing section to see what kind of success people are having with certain brands and certain compounds. If in doubt, go stickier.

If you have to run on street tires, don’t do a burn out. Street tires don’t work like drag tires. Getting them hot makes them slick. Just a quick spin to get the dirt off is all you need. Also, DRIVE AROUND the burnout box. You’re not doing a burnout anyways. By driving through it you’re just sloshing water into the staging area and making your tires even slicker.

www.discounttire.com
www.tirerack.com
www.discounttiredirect.com

Tire pressure
This will vary by the tire, so it’s abit of experimenting with this one. First off over inflate the front tires 8-12 psi. Over inflated = less contact patch = less rolling resistance.

Now to find the sweet spot with the rears. Have them inflated to their full pressure. Right off the bat you can probably drop them 5psi. Now go take two runs and then drop them 5 more psi. Rinse and repeat until you get really good 60ft times.

With manual cars your rear pressure will be lower than on auto cars because the shock to the drive train is more. So you auto guys wont need to drop your psi as much.



Gearing:
This is what should be another de facto upgrade. Everyone but our community does this off the bat. If you show me someone that says short gears are unusable with any decent amount of horsepower, ill show you someone that doesn’t know a properly set up suspension from their own asshole. I have heard too many people say to stay away from the 4.3s because they are just spin fests. If someone tells you that, dont listen to any of their advice again; they just let you know they don't know shit.


The domestic 1/8 mile guys run gears in the 6.x range with more horsepower than anyone on this whole board makes. Yet they have no problem hooking. It’s called proper setup and good tires.

Here are our choices: 3.7, 3.9, 4.1, 4.3. If you want to go faster in the 1/4 mile, you need a higher number. If you have a 3.7 try going up to a 3.9, if that’s not enough try the 4.1, etc. etc.

The main point of concern is if you are a manual. You might have issues where you are redlining 200 ft out. Not enough time to shift, but coasting will just kill your times. In this situation you might want to step back a gear. OR get some taller side walled tires. A simple taller tire change can cure those shifting blues.

Going from 3.7 to 4.3 is a tremendous difference and your times will reflect it.


Weight:
Every 100 pounds lost = 0.1 faster in the quarter mile. With our portly cars, that’s means you can potentially go much, much quicker by shedding some weight. It also explains why your car with the mad tight system with four 15in subwoofers is so slow. Take that shit out if you’re going to go to the track.

All weight loss is not good weight loss though. If you only remove weight from the rear of the car, you wont be able to hook. You do need weight over the tires to make them hook.

When removing weight, try to keep it even or take more weight off the front. Our cars are nose heavy anyways, so try and work up there. If you can move things to the back, do so; such as the battery.

Also remember that every 1 pound of rotational mass = 10 pounds of static mass. If you go from the stock 28 pound drive shaft to a 15 pound one piece steel one, it’s like you removed 130 pounds from the car’s frame. This is another reason why you shouldn’t try and drag with those heavy ass 18s of yours. Get you some nice light rims.

Cheap trick-- If going to the track by yourself, take out your driver's side seat completely. Put the passenger's in it's place. Instant 80 pound weight loss.
 
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outofstep

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#2
At the Track
Keep your car off as long as you can while in the lanes. Heat soak is not your friend. Ever wonder why some people push their cars while in the staging lanes? Keeping them cool by keeping them off.

Pop your hood while in the staging lanes, let it get nice and cool in there. Just make sure your hood is nice and securely closed about 3 cars prior to running.

Like mike said, while driving back to the staging lanes after a run; have your heater on full blast. Keep that heat out of the engine bay.



Those sneaky tricks:
Bring a spray bottle of rubbing alcohol. While in the staging lanes spray down your intercooler, hard pipes, and intake manifold. It’s great for cooling things with a quickness.

Most tracks do not allow ice baskets. So what you can do instead is get those blue cooler deals. You know, those little blue things you stick in the freezer and use to keep your food cold when you go to a party/camping. Get you a nice waterproof cloth bag, cut open and dump the contents of the blue freezer deals into it. Sew it shut. Throw it in the freezer. You just made yourself a frozen intake manifold blanket. They actually sell this exact same thing for like 200 bucks but you made it yourself for 25. If you have any craft skills you can custom make it to your intake manifold. Or just go generic blanket style. Your choice.

Don’t want to spend the cash on a C02 or N02 intercooler sprayer? Just get the bottle then and some extra tubing. Make sure you hold the bottle upside down, point the tubing at your intercooler and spray away.

Here’s one from mike. Stage shallow. Just barely get the all good lights to come on. That way you’ll be rolling before you break the track lights. You know, kinda cheating but not really? Haha.

Here’s another one from mike. Clean and wax your front bumper, hood, roof. Wind drag goes up cubed (or is it squared? I forget) after 60mph. I don’t know about you, but I go abit faster than 60mph in the quarter mile. Less drag = faster times.

Over all:

It should take very little work to get your car fast. It’s just a matter of doing it right. Get your suspension set up right, get some good tires, practice launching. This 14 second BS is killing our reputation. Get a stall, drop some weight, use some of the hints. BPU MK3s should realistically be in the 12s, they make enough power and are light enough to be there.

If you want more drag racing hints, visit some domestic board. Whatever you do, don’t listen to other Supra owners. They have proven they don’t know what they are doing.
 
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JDM 1JZ

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#3
hey out of step i might have one i dunno if this would apply to the supra though. have you ever heard the trunk spring trick that muscle car old heads use. they disconnect the springs to there trunk so that it doesnt trap weight of the trunk at the "top" of the trunk. by disconnecting it drops the weight of the trunk over the back of the car. i dunno if i explained that so good haha, would that work on the supras with out the air shocks cause are hatchs are real heavy with out them and im sure it will trap alot of weight over the rear axle instead at the top of the window
 

outofstep

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#4
You mean change the connection point to force a weight distribution change?

I wouldnt think that would change very much becuase the hatch rests along weather stripping all the way around. So the weight distribution is already spread about the edges.

I dunno. :shrug:
 

JDM 1JZ

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#5
outofstep said:
You mean change the connection point to force a weight distribution change?

I wouldnt think that would change very much becuase the hatch rests along weather stripping all the way around. So the weight distribution is already spread about the edges.

I dunno. :shrug:
yeah im not sure that it works also i just hae alot of muscle car friends that do it and have tested it with results. i live in a town with alot of old head muscle car guys and rat rodders and such and they all swear by it, just thought id share
 

GrimJack

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#6
Damn, I'm freaking KILLING myself laughing here. Dead on target on all points though. Rarely have I seen worse times from cars with similar power / weight characteristics.
 

87supraturbo19

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#7
i kinda felt the same way about all the 14s. everybody was starting to make me feel like my car just seemed fast but i swear with bpu you should be in the 13s.
 

silvergsx623

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#8
Very good post.

i learned something about the camber, i never thought about that before.

:-D *thumbs up*
 

Godspeed

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#9
good post i myself have only been to the track 2 times and made several of these mistakes but i'll know next time. thx
 

aye mate

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#10
Awesome post Outofstep. Personally I have made it a point with myself to not upgrade my turbo until I am in the 12's. And some sticky tires are definatley in order.
Also something else that I did my last time at the track was open the downpipe. I found that this helped immensly with topend. Now my cat-back isnt the best in the world either, but my times went from 14.3 to a 13.7 with the same exact 60' time. The only difference was the open downpipe.
 

Anomili

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#11
Well done, I still doubt it will save my time when I finally get around to going to a track for the first time.
 

supra87t/t4

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#14
Take that "rant" crap out of there, that's just stupid. Nobody is harming the community by running poor 1/4 mile times and anyone who would take something written in that tone seriously should probably avoid the internet alltogether (I certantly hope you didn't write that part yourself). Most MKIII people don't take drag racing seriously, and that's fine, they probably didn't buy a MKIII to make it into a dragster. Talking about them like they are morons and they are making you look bad is only going to discourage them from trying, or at least from posting their results. I don't think very many people do well at drag racing on their first attempt, practice will probably have a bigger affect than anything you posted in this whole thread, and you are discouraging that by making people hesitant to try for fear of failure, hesitant to post results for fear of getting flamed and hesitant to try again if their first attempt doesn't go well (which it probably won't). OK engouth anti-rant ranting from me.


I don't agree with your clutch theories, the track will either have more or less traction than the street (at least around here some have less) Obviously you need to put down as much power (torque) as the track will hold, you can change this somewhat with your launch rpm, but you can totally change it with how you release the clutch. If you let the clutch out on the street like you would in a drag launch and you don't have the rpm's up your going to kill it.

Boost on the line is going to be the second biggest drivetrain killer right after slicks, it's not for everybody.

I think disconnecting the sway bar is going to have more of an effect the more your car "twists" off line, which is alot more ponounced in cars with a solid axle. If both front tires droop together, the friction of the sway bar turning in its mounts isn't goign to have any significant effect on weight transfer. Then again, I've never tried it.

The camber comments are true, but again how many people take dragging seriously enough to mess up their street settings.

You should definantly have a pair of rims and tires just for dragging, 15" rims fit over the stock calipers, which gives you the best selection of tires.

Totally agree on gearing, people may need to adjust their driving to the 4.30, but it is definantly going to be faster. As far as a spinfest, that means your tires/suspension sucks, not the gearing.

Less weight is better obviously, don't hesitate to take weight off anywhere you are willing to. The lowest overall weight is first priority, then worry about how is is distributed.

You need to mention shift points, I firmly believe that unless there is something wrong with your engine you need to shift at redline, if shifting earlier makes you faster something is wrong.

Also mention pre-loading the drivetrain and avoiding wheel hop as critical to drivetrain longevity, shock loads are killers.

Glen
 

supra90turbo

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#15
Thank you. Happy I could help :icon_razz
Oddly enough, I was browsing the site, ready to order some parts moments before I read this thread.

i lol'd at this part!!
outofstep said:
Whatever you do, don’t listen to other Supra owners.
They have proven they don’t know what they are doing.
 

souprat

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#16
THANK YOU OUTOFSTEP. THANK YOU OUTOFSTEP. i'll be at the track this saterday and i've read the writeup on sf about launching but this is very in depth about everything else involved in drag racing. i will definatly give all of this a try.
 

hawk

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#18
can we get a chart showing top speed for each gear set for both auto and 5spd? possibly at each gear change. also using the stock sized saw blades and oem tires?
 

GrimJack

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#19
That would be very complex, considering that we have three different rear end gearings, three different trannies, two stock rev limits, and a host of aftermarket changes that might affect this as well...
 
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#20
Good post, but I like being overlooked at the drag strip. So everyone please keep up the 14 second time slips so that when I race, they won't see me coming with the 10's and 11's
 

aye mate

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#21
hawk said:
can we get a chart showing top speed for each gear set for both auto and 5spd? possibly at each gear change. also using the stock sized saw blades and oem tires?
this is the closest thing I found.
shaeff said:
origionally posted by OUTOFSTEP
outofstep said:
:

Here is a listing of the various top speeds for the different transmissions and rear ends.

Automatic tranny, stock size tire (225/50/16):
3.73 rear @ 7000 rpm 4th gear = 199 mph
3.91 rear @ 7000 rpm 4th gear = 189 mph
4.30 rear @ 7000 rpm 4th gear = 172 mph

Automatic tranny, common upgrade size (255/45/17)
3.73 rear @ 7000 rpm 4th gear = 207 mph
3.91 rear @ 7000 rpm 4th gear = 198 mph
4.30 rear @ 7000 rpm 4th gear = 180 mph

Manual tranny (turbo), stock size tires
3.73 rear @ 7000 rpm 5th gear = 185 mph
3.91 rear @ 7000 rpm 5th gear = 176 mph
4.30 rear @ 7000 rpm 5th gear = 161 mph

Manual tranny (turbo), upgraded size tires
3.73 rear @ 7000 rpm 5th gear = 194 mph
3.91 rear @ 7000 rpm 5th gear = 185 mph
4.30 rear @ 7000 rpm 5th gear = 168 mph

Shits n Giggles calc

auto tranny with 245/65/18 (yes, these fit just fine)
3.73 rear @ 7000 rpm 4th gear = 243 mph
 

diy guy

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#23
this takes a bit more practice, but you can prespool the turbo in your manual by holding the ebrake up (preloading the drivetrain, i think someone mentioned it). a little more wear on your clutch but its easier on the tranny itself since it eliminates the slack between gears/shock when you launch.

also I if youre new to drag racing, you may think your reaction time is related to e.t. or 60ft and jump the gun. ITS NOT. the time doesnt start until you trip the sensor so take your time and concentrate on what your doing.
 

GrimJack

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#24
diy guy said:
also I if youre new to drag racing, you may think your reaction time is related to e.t. or 60ft and jump the gun. ITS NOT. the time doesnt start until you trip the sensor so take your time and concentrate on what your doing.
Err... this depends on what kind of racing you are doing. I've never seen a street legal style race that uses reaction time... but it's there for a reason, lots of race types do.
 

diy guy

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#25
some include it in bracket racing et, but chances are you wont be doing any competitive racing your first time out ;)
 

JimR

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#26
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outofstep

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#27
Optimum shift points are almost always redline. Every time you shift, you are no longer accelerating. I'll take a slight decline from peak horsepower over ZERO horepower while shifting and then subsequent respool and then eventual climb back up to peak horsepower.

You want to maintain acceleration as long as you can, you do this by staying in gear as long as you can. The instant you disengage you begin decelerating. Keep that to a minumum by staying in gear as long as possible.


The only times you need to calculate shift points is if you have a car that drops off just a retarded amount of horsepower before redline. Our cars don't do that even stock. If you've got any upgraded or larger turbo, you shouldnt drop off much at all before redline.
 

snake eyes

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#29
outofstep said:
Optimum shift points are almost always redline. Every time you shift, you are no longer accelerating. I'll take a slight decline from peak horsepower over ZERO horepower while shifting and then subsequent respool and then eventual climb back up to peak horsepower.

You want to maintain acceleration as long as you can, you do this by staying in gear as long as you can. The instant you disengage you begin decelerating. Keep that to a minumum by staying in gear as long as possible.


The only times you need to calculate shift points is if you have a car that drops off just a retarded amount of horsepower before redline. Our cars don't do that even stock. If you've got any upgraded or larger turbo, you shouldnt drop off much at all before redline.
commented on the sf thread, but got to argue this point, i shift at 55xxprm, why? because when i dynoed the car it was falling off so bad and i could feel it fall off that it was killing my MPH and times, now i just got a cutout so ill see how it feels but with a 3in exaust all the way back with a working cat, 8psi and intake the power fell off like a mofo

im gonna redyno it with the cutout off, so maybe that will change the curve

graph link: el linko

<l><l>
 

JimR

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#30
Me and outofstep PM'd on this subject. Here are my current thoughts:

The number of times you have to shift while going down the strip will likely remain the same, whether you shift at redline, or slightly before. If you can avoid a shift by going to redline, then by all means do this!

However, if you cannot save a shift, then the amount of time spent with zero power (in the middle of the shift) remains constant, and so it makes sense to calculate your optimum shift points for "maxiumum power under the curve".

For most of our cars that have been upgraded, the optimum shift point will be above redline for all gear shifts. But I maintain that it is still a good idea to get your dyno graph out and plug in the numbers.

Jim
 
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outofstep

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#31
Maybe I didn't get it across well the first time.

It's an integration problem for dH/dT over total rpm. Maximising total area under the curve. So unless you have crazy retarded drop off before redline, optimum shiftpoint will always be redline.

This becomes even more so the case with anything larger than stock.

Very few turbo cars need to shift before redline, it's the nature of the beast; it's turbo. I have seen many NA cars where you actualy would want to shift before redline. But it's going to be so rare a case on our cars, that's it's pretty much not even worth worrying about. If you actualy do have a situation that would cause for shifting before redline with a turbo 7M, something is wrong with your engine...
 

swaq

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#32
Heckler said:
Me and outofstep PM'd on this subject. Here are my current thoughts:

The number of times you have to shift while going down the strip will likely remain the same, whether you shift at redline, or slightly before. If you can avoid a shift by going to redline, then by all means do this!

However, if you cannot save a shift, then the amount of time spent with zero power (in the middle of the shift) remains constant, and so it makes sense to calculate your optimum shift points for "maxiumum power under the curve".

For most of our cars that have been upgraded, the optimum shift point will be above redline for all gear shifts. But I maintain that it is still a good idea to get your dyno graph out and plug in the numbers.

Jim
Like outofstep said, it's about area under the curve, not the time spent at zero power. If you spend a second at zero power at 60 mph this hurts your time more than if you were at 80 mph. You can graph this if you want. Figure out how far you'll go in a fixed amount of time with a shift at one speed as opposed to a shift at a higher speed. You'll find that you'll cover more distance in the same time if you shift at a higher speed with the same number of shifts. This is just a simple calculus concept.
 

IHI-RHC7

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#34
True, but our dyno graph does fall off, because we're producing 460 ft-lbs of torque at 2800 rpm from a stock ct-26, this leads to a massive heap of midrange power, but typical, ct-26 top end. Consequently, by the time the engine gets to 5250, power has peaked, due to the surge of midrange torque, and power is on it's way down.
This is not a problem with the engine, it is getting the most midrange power from an undersized turbo. Short shifting at 5500 allows the engine to maximize the power under the curve, and helpped out a ton.
In a stock car, this would be non-sense, but the CT gives a ton of midrange power, and staying in the high revs would negate this power, as it behaves very much like a typicle, 300 hp mkiii above 5K.
Below 5K, it owns. ;)
 

TurboStreetCar

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#35
just a little comment on the higher stall converters. they usually go for about 450, not ~200. ive called around to a few places and its all in the mid 4 range. i called hughes, pro-torque, IPT and another place i dont remember the name and they all wanted around 450 to rework the stock converter to around a 3k stall.
 

SupraOfDoom

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#37
I will be building an upgraded CT car this winter, my goal is to beat MKIIISupraGuy's record on the upgraded CT in the 1/4th. This thread along with loads of practice at Great Lakes Dragaway ( Same place he got the record, 12.1 ), will hopefully help me out.
 
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#38
True, but our dyno graph does fall off, because we're producing 460 ft-lbs of torque at 2800 rpm from a stock ct-26, this leads to a massive heap of midrange power, but typical, ct-26 top end. Consequently, by the time the engine gets to 5250, power has peaked, due to the surge of midrange torque, and power is on it's way down.
This is not a problem with the engine, it is getting the most midrange power from an undersized turbo. Short shifting at 5500 allows the engine to maximize the power under the curve, and helpped out a ton.
In a stock car, this would be non-sense, but the CT gives a ton of midrange power, and staying in the high revs would negate this power, as it behaves very much like a typicle, 300 hp mkiii above 5K.
Below 5K, it owns. ;)

I have to say that the torque you're putting out isn't going to be a big deal after you've started moving already. If we're talking shift points here we want to think about staying in the HP band as much as possible when shifting from 2 to 3 and from 3 to 4. You may have to shift 4 to 5, but it's unlikely if you have a good gear set. If you have your HP graph this is an easy thing to think about, or if you're mostly stock I'm sure somewhere you can find the graph online. What we're looking for is the HP peak. We want to have a target shift point just after power starts to drop off. This is because of one thing, none of us is going to shift faster than about 1/2 a second unless power shifting which I agree isn't worth a blown tranny. If you have a shift light, set it at the peak of your HP RPM, only because again, none of us are machines and it will take a 1/2 second to realize the light is on, which puts us at a perfect shift point to shift above the HP peak, lose that 1/2 second shifting, and probably 1500 RPM and put us right back near peak HP keeping us in the band as long as possible. Another thing to think about is shifting before crossing the line. If you can hit your rev limiter before getting too close to the line, shift. If you're just about to hit it, or bounce once, I wouldn't worry about losing that time shifting, the limiter is there for a reason...to save your engine and turbo. In a perfect world you'd be across the line, full throttle, in 4th gear just over your HP peak or at redline.
 

turbogeek87

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#39
I agree totally. If you can't do better than 14 seconds with BPU your a friggin embarrassment to the supra community. For shame!
 
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