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Time Warp
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Discussion Starter #1
Ok since I've joined the ranks of the starving college students, the tranny swap I had planned might not go through. But I just hate the lack of control the auto gives. I'm new to automatics, so can anyone tell me about torque converters? What do they do? Would an almost stock car benefit from having one? How does it feel to drive a car with one on? Or just any info you guys could give me, I'd really appreciate it. Is it worth it??? Dunrite's shop is REALLY close to where I live, so I've been seriously considering that option. Any help or suggestions on this subject would be appreciated. TIA

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Jae
'00 SE w/ some stuff...
Desperately seeking an SOHC VTEC... yes, I'm serious.
 

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yeah you really should get one, get it ASAP. you should get one that is about 1000RPM over stock stall, but you can get one that is even greater but am not sure what the sideeffects would be. 1000 over stock should be good. The torque converter will give better response than the stock one, and if you get a shift-kit custom made to fit your car then your car will shift equally with the 5-speeds. A good price for a custom made torque converter is around 300-400 dollars, and a shift-kit should not cost more than 125. Dont go too crazy with the amount over the stock stall, cuz our cars dont have enough power for a 300RPM stall converter. But if you get one you will see how much harder your tranny shifts, and the added response and acceleration are amazing. I have done this in an auto. 5.0L mustang and it actually dropped almost half a second off the quarter mile e.t. let me know how much you get it for and all the details, like how much the stock stall is. This is probably the best mod for the money for an automatic car. Ok enough my hands are tired.

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formerly known as JCGator42, 2k1 Nissan Sentra SE w/PP mods: Cold Air Intake by Hotshot, and Stromung Cat-Back Exhaust(on its way over here), and Unorthodox Underdrive 4 pulley set(in a couple of weeks) [email protected]
 

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Time Warp
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Discussion Starter #3
A response to my post! Not much love for automatics in here, eh?

Anyways, thanks 2k1Drag. But can you explain a few things to me? Like I said, I'm new to automatics. What's this stall you were referring to? And if you get a shift-kit, how do you use it? Is it like a seperate knob or does it replace the stock auto-shifter? I'm not really sure how this works. Good gawd, almost half a second? Not bad... well get back if ya can. Thanks in advance again.

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Jae
'00 SE
Huh? Seeking an SOHC VTEC? ME??? You must be mistaken... ;)
 

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The stock stall is 2600 for us. (Put the car in 1/2/D, hold the brake pedal and rev). When the rpms don't increase anymore, this is the stall. You can always drive in 1 or 2 and then just shift into D (with O/D off) when you feel like it (as long as you don't over-rev and hit the limiter), to get better control. Of course doing this continuously for years could shorten the life of the tranny, I don't think anyone here knows for sure. Most agree that you shouldn't get it over 3K, and I think most of the older sentra owners that have raised theirs only go to 2600 or so, so I think that our's is fine. You might want to look into a valve body kit that should give you tighter shifts (I think this is the same as a shift kit, but not sure). Plus that way you should be able to do the procedure I described above w/o as much damage (if any) to your tranny.
Point is there are things out there to get better response from an auto. See Monopoli's page, his SR20VE-T NX is auto.
 

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The stock stall is 2600 for us. (Put the car in 1/2/D, hold the brake pedal and rev). When the rpms don't increase anymore, this is the stall. You can always drive in 1 or 2 and then just shift into D (with O/D off) when you feel like it (as long as you don't over-rev and hit the limiter), to get better control. Of course doing this continuously for years could shorten the life of the tranny, I don't think anyone here knows for sure. Most agree that you shouldn't get it over 3K, and I think most of the older sentra owners that have raised theirs only go to 2600 or so, so I think that our's is fine. You might want to look into a valve body kit that should give you tighter shifts (I think this is the same as a shift kit, but not sure). Plus that way you should be able to do the procedure I described above w/o as much damage (if any) to your tranny.
Point is there are things out there to get better response from an auto. See Monopoli's page, his SR20VE-T NX is auto.
 

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Yes please tell us more!!!! I'm interested in this type of upgrade myself.

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2001 Blackout SE w/ PP, sunroof, debadged, Stromung exhaust, more to come...
 

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Ok, if 2600rpm is the stock stall, then that is good enough, I will get mines up to 4k anywho just for my own fun. A shift kit is not separate from the knob or anything, it is a series of gaskets(metally sheets of metal) that change the way the valve bodies arrange the shifts, so your tranny shifts harder, there is almost no slippage which is what autos are known to do, so your tranny will not suck as much power from your drivetrain, and well overall everything is pretty much improved. Like in my friends auto mustang, his car now peels out when shifting from 1st to 2nd and from 2nd to 3rd before only peel out at start was possible. The difference was actually a lot. for our cars am pretty sure it would not be as much, but it would be respective in the amnt. of gains. Acceleration is improved overall. By the way there are different kinds of stalls, I just don't remember the names, the one you refer to is flash stall which is done by holding the brake, but I don't think that is the one they use when considering the stock stall of your torque converter. Well, just take your car to a good tranny. ASE certified shop that will give you at least a years warranty then have them do it and explain you the process. sorry for the long post, am just trying to help. Juan

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formerly known as JCGator42, 2k1 Nissan Sentra SE w/PP mods: Cold Air Intake by Hotshot, and Stromung Cat-Back Exhaust(on its way over here), and Unorthodox Underdrive 4 pulley set(in a couple of weeks) [email protected]
 

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If you have an auto. and think you are off par with the 5-speeds, just remember this, the fastest Supra in the world is an auto. well it was when I read it about a year back, maybe things have changed, but my point is that with enough money anything is possible. hehheh :)

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formerly known as JCGator42, 2k1 Nissan Sentra SE w/PP mods: Cold Air Intake by Hotshot, and Stromung Cat-Back Exhaust(on its way over here), and Unorthodox Underdrive 4 pulley set(in a couple of weeks) [email protected]
 

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Time Warp
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Discussion Starter #9
K... so from what I understand, we may not really NEED a torque converter because our stock stall is good enough. What we REALLY need is a shift kit. Did I get that right?

Damn, I need to do some more research on this...

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Jae
'00 SE
Missin my Civic, lovin my Sentra.
 

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Maybe, maybe not....definately get a shift kit, but have the shop check your stock stall anyways, everyone is referring to Flash Stall which I am pretty sure is not what they use, but just go get the stuff done, I know I will soon. :)

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formerly known as JCGator42, 2k1 Nissan Sentra SE w/PP mods: Cold Air Intake by Hotshot, and Stromung Cat-Back Exhaust(on its way over here), and Unorthodox Underdrive 4 pulley set(in a couple of weeks) [email protected]
 

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Auto's can be very fast, but you need to make more power to keep up with a manual with similar mods because of the power you with an auto. the more power you make, the more you lose with the auto.

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Ryan 97 Black SE-R
Custom 2.5" mandrel bent exhaust with dynomax super turbo muffler, Hotshot Cold Air Intake, Unorthodox Racing Pulleys (2set), Nis-knacks clear corners, timing at 19 degrees, Hotshot header(installing this week)
aim Stea1th727
 

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The nature of torque converters allows them to transmit more torque to the wheels than a manual. Usually at lower rpm's.

At least that's what my auto shop teacher told me.

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My dream.......is a heated 100 car garage, a nice little house and a racetrack for my driveway......oh yes, a gorgeous & rich wife would be nice too!
 

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yeah it's true, you can see the difference in the dyno charts of a auto tranny car. BUt anywho I think putting a shift kit in, some slight valve-body work, and maybe a lightened flex-plate(flywheel), along with a 500 0r 1000RPM over stock stall converter, if you do all those 4 things your car should be just as fast or faster than a 5speed with the same mods. Let us know what happens with the work they do on your car, Juan :)

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formerly known as JCGator42, 2k1 Nissan Sentra SE w/PP mods: Cold Air Intake by Hotshot, and Stromung Cat-Back Exhaust(on its way over here), and Unorthodox Underdrive 4 pulley set(in a couple of weeks) [email protected]
 

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Time Warp
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Discussion Starter #14
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by racemann:
The nature of torque converters allows them to transmit more torque to the wheels than a manual. Usually at lower rpm's.

At least that's what my auto shop teacher told me.

<HR></BLOCKQUOTE>
Where does this torque come from? Sounds good to gain torque in the low end, but you don't lose any high end torque do you?

Sorry for all the questions guys, I still haven't had time to research this topic yet...




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Jae
'00 SE
Missing my Civic, but loving my Sentra.
 

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No I don't think you lose any torque at all, you actualy gain some in the lower end of the rpm range, but you do lose a substantial amount of horsepower, nothing a lightened assembly wont fix. Some cars that rate their toque even up to 15 less than the hp, actually make more torque to the wheels than hp when dynoed, I am really not sure why, so I will ask my master mechanic the question when I get my exhaust installed this weekend.

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formerly known as JCGator42, 2k1 Nissan Sentra SE w/PP mods: Cold Air Intake by Hotshot, and Stromung Cat-Back Exhaust(on its way over here), and Unorthodox Underdrive 4 pulley set(in a couple of weeks) [email protected]
 

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Time Warp
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Discussion Starter #16
So you're going to need a lightened flywheel, valve body work, shift kit, torque converter... to keep up with a stock 5-speed? Sounds like all that is going to cost about the same as a 5-speed tranny swap.

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Jae
'00 SE
Missing my Civic, but loving my Sentra.
 

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Al, The Ignorant Fcuk
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I would think unless you are racing your Sentra, (In which case you are probably not overly concerned about life of the car and warranty) a different torque converter is risky. What does it do to the warranty of the present transmission- answer-void.
I understand the stall speed, but what bothers be is that if it has a higher stall-it must have more slipage. You will have more horsepower on tap due to the higher speed of the engine when you release your brake. I am though still leary of how much of that HP goes to the wheels in light of that higher slipage. How about fuel economy? I think going with a different converter is a high risk exercise for a small improvement (if this pans out)in performance. You may recall, my SE had a bad torque converter out of the chute- cost of repair $1600 (not to me). Auto-trannies are expensive and usually when they are worked on its time to think about selling the care. They are incredibly complex.

Just my $.02

I would still like to know if the slipage allowing higher stall is of any value. One other thing. Will this converter lock up at normal highway speeds??

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Plain Jane Cappuccino SE
with AutoTrans
 

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Time Warp
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Discussion Starter #18
Good points. I hadn't even thought of those. Then again, I know nothing about auto trannys so...

But yah, I was thinking of the warranty too. I would be putting myself on ice. If my tranny broke down, it would be all over. Plus, you're right. I don't plan on making my car a drag car. It's my daily driver. I'm just looking for a little extra performance.

Maybe I should think about doing a 5-speed swap again... AFTER the warranty on my auto tranny runs out.

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Jae
'00 SE
Missing my Civic, but loving my Sentra.
 

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Actaully, I doubt it would cost the same to do the 5 speed swap. Would you get a new tranny or refurbished? Factor in installation, then the cost of a new or reprogrammed ecu (which aren't even out yet)and you're probably looking at more. I don't think any of the actual parts (if you're going to use core cost of your original torque converter) would add up to more than the cost of a new 5-speed, except maybe with the flywheel. Only expensive thing is the labor, as usual.
 

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yes those are excellent points there, but most of the time those problems arrive when the stall profile increases way too much over the stock like 1000RPM or more, if you only go up 300 or up to 500RPM over stock stall I am 90% sure that you would be fine, but if this is your daily driver then I suggest sticking with just a shift kit, if you go with a 3000+RPM stall coverter then I am almost positive our cars don't have enough power for one of those, and your converter will surely lock up during regular driving, you converter locking/slipping up at like 4th gear(overdrive) like 100 miles an hour would be really horrible, that could lead not only to a gone tranny but to a blown piston and to a nice hole on the block(trust me I know). but just doing the shift-kit alone would make an amazing improvement, like .2 seconds. Talk to your ASE certified transmission mechanic cuz my knowledge stops there. Does anyone know if our cars use flexplates or flywheels on auto tranny cars? I really want to know, thanks and hoep this helps. Juan

P.S. - A really good idea would be to get a tranny from a 5-speed tranny/differential combo from SOHO or some other major tranny/enigne sales co. from a 91-94 SE-R. The swap should not be that hard, but it is very time consuming, lots of drilling and modding of the console. ok there ya go :)

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formerly known as JCGator42, 2k1 Nissan Sentra SE w/PP mods: Custom Aluminum Mesh Front Grille by Myself, Cold Air Intake by Hotshot, and Stromung Cat-Back Exhaust, and Unorthodox Underdrive 4 pulley set(in less than 2 weeks) [email protected]
 
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