HP increase from a converter
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From: Seattle,Wa.
HP increase from a converter I realize that by putting in a stall converter in my T/A that it will not increase my HP, however, there must be some kind of comparison because you would better your ET while drag racing. Can someone help me out here to better understand what I'm getting at.
A high stall would be equivalent to some kind of HP or even torque increase....am I right?
A high stall would be equivalent to some kind of HP or even torque increase....am I right?
ET are based off of your launch and mostly available torque (in 1st gear). If you want to see if a mod netted an increase in HP, look at your MPH. If it consistently went up then you gain (for example) 10 HP for a given 1 MPH. Typically a variance in 1 MPH is not enough to qauntify a HP gain. Most converters will keep the MPH the same at the end of the track. Low stall converters (like my B&M 2600 that I finished testing) can gain a MPH on the traps, but won't result in great ET performance.
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From: NE PA
Aftermarket torque converters improve the performance of your car in two ways. The first way is off the line via its higher stall speed and increased torque. The second real advantage that higher stall speed torque converters provide is what's called “shift extension.” When your tranny shifts at WOT, instead of the engine speed dropping down to 3500 rpm or lower, it will stay at 4000-5000+ rpm and you'll be right back up to redline again for your next shift. This keeps your motor in the meat of its power band the whole run which in turn translates into improved ETs. An aftermarket converter also eliminates the “dead spot” that stock converter cars suffer from because now when you stomp on it and your tranny kicks down into passing gear, instead of your engine having to build up engine speed from the 3000 rpm range, you'll be starting at a much higher rpm and this results in better acceleration, performance, and times. 
Troop's got it...
One more little item, I found with the smaller size of the new high stall converter ( less weight) the motor spins up ALOT faster than with the stock (larger sized-heavier) converter.
Any loss in weight on your car will result in stronger performance. I went from stock, to a 2600 stall, then to up to a 3200 stall....big diff. in these stalls.
Really happy with the performance gains from a stall. Definately a must when modding these LS1's.
Kev
One more little item, I found with the smaller size of the new high stall converter ( less weight) the motor spins up ALOT faster than with the stock (larger sized-heavier) converter.
Any loss in weight on your car will result in stronger performance. I went from stock, to a 2600 stall, then to up to a 3200 stall....big diff. in these stalls.
Really happy with the performance gains from a stall. Definately a must when modding these LS1's.
Kev
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From: NE PA
Originally Posted by K9Kev
Troop's got it...
One more little item, I found with the smaller size of the new high stall converter ( less weight) the motor spins up ALOT faster than with the stock (larger sized-heavier) converter.
Kev
One more little item, I found with the smaller size of the new high stall converter ( less weight) the motor spins up ALOT faster than with the stock (larger sized-heavier) converter.
Kev
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with a converter you actually LOOSE alot of rwhp. i've heard of people loosing 20rwhp going from stock to a 3500-4000 stall (can't remember the exact #'s but it is somewhere around there). obvously peak hp does not always tell the tale though and the hp/tq curve is what makes the car alot faster.
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From: Texas
Originally Posted by Fast Eddie's 02 T/A vert.
I'm thinking a 3200 or 3500 stall. It's going to be my next mod.I want the T/A streetable.
Thanks for all of your responses.
Thanks for all of your responses.
yes- the tci has (fwiw) high str- so it is good on the street for driveablilty BUT makes it harder to hook with because it hits harder. this makes it actually worse to race with on the street. a looser verter (like some of the yank converters and i've heard vig's) will make it much easier to launch on non-slick tires.
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From: Texas
Originally Posted by sleeperstyle
yes- the tci has (fwiw) high str- so it is good on the street for driveablilty BUT makes it harder to hook with because it hits harder. this makes it actually worse to race with on the street. a looser verter (like some of the yank converters and i've heard vig's) will make it much easier to launch on non-slick tires.
I think perhaps you are confused. A lower STR stall hits harder (as in at a higher rpm), that is why they are so good at the track. A higher STR stall does well on the street because it is tighter(not hitting as hard). A lower STR feels looser and does well at the track because it gets you in the power band quicker.
Originally Posted by 2MuchRiceMakesMeSick
Remember that a 3500 stall will not rev to 3500 every time you go from the light. Only when you flash it will it get into that range. Also the STR plays a big role in how streetable the stall is. The higher the STR, the more tighter it feels.
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From: Halfway back on the Highway to Hell...again!
you have 2 types of stall; brake stall- when you hold the brake and push on the throttle to just before the tires start to spin. That rpm will be your brake stall rpm.
To flash it, means to sit at idle and just hammer it down. The rpms will "flash" the converter and lock at a much higher rpm, thus giving you your flash rpm. Depending on your suspension mods or the the car itself, being every car reacts differently, one style will prove to be better than the other. Also, aot has to do with the surface you're racing on, tires, wheel size, gear ratio, etc. If you plan to flash above 3k often on a stock rear, start saving for that Moser now. Tire size, gears will also have play a role in stall rpms also. There are many things that decide on stall characteristics.
To flash it, means to sit at idle and just hammer it down. The rpms will "flash" the converter and lock at a much higher rpm, thus giving you your flash rpm. Depending on your suspension mods or the the car itself, being every car reacts differently, one style will prove to be better than the other. Also, aot has to do with the surface you're racing on, tires, wheel size, gear ratio, etc. If you plan to flash above 3k often on a stock rear, start saving for that Moser now. Tire size, gears will also have play a role in stall rpms also. There are many things that decide on stall characteristics.
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From: NE PA
Originally Posted by 2MuchRiceMakesMeSick
I think perhaps you are confused. A lower STR stall hits harder (as in at a higher rpm), that is why they are so good at the track. A higher STR stall does well on the street because it is tighter(not hitting as hard). A lower STR feels looser and does well at the track because it gets you in the power band quicker.
The STR has little or nothing to do with getting "you in the power band quicker" as this is controlled by the stall speed of the converter, not its torque multiplier which is only a factor when your car first starts to move off the line and then rapidly diminishes. It's the stall speed that "slips" your motor into a higher rpm range. The higher the stall speed, the faster and higher up in the rpm range your motor will move.
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From: Texas
Originally Posted by XTrooper
Actually, you're the one that's confused. You have two things mixed up STR (stall torque ratio) aka torque multipler and stall speed. A lower STR increases torque with a smaller multiplier thus it hits softer than one with a higher STR that uses a larger multiplier and hits harder because the torque is more greatly multiplied. Most prefer the harder-hitting, high STR converters for track use as evidenced by the high STR of race converters.
The STR has little or nothing to do with getting "you in the power band quicker" as this is controlled by the stall speed of the converter, not its torque multiplier which is only a factor when your car first starts to move off the line and then rapidly diminishes. It's the stall speed that "slips" your motor into a higher rpm range. The higher the stall speed, the faster and higher up in the rpm range your motor will move.
The STR has little or nothing to do with getting "you in the power band quicker" as this is controlled by the stall speed of the converter, not its torque multiplier which is only a factor when your car first starts to move off the line and then rapidly diminishes. It's the stall speed that "slips" your motor into a higher rpm range. The higher the stall speed, the faster and higher up in the rpm range your motor will move.
https://ls1tech.com/forums/showpost....5&postcount=20
Higher STR, feels tighter
Originally Posted by 2MuchRiceMakesMeSick
As for the original question of the post about increasing hp, no you will not dyno higher, but the higher stall and better shift extention does increase your average horsepower put to the ground throughout the 1/4.
later
Last edited by Top Fuel; Dec 4, 2004 at 12:38 PM.
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From: NE PA
Originally Posted by 2MuchRiceMakesMeSick
Higher STR, feels tighter
"A lower STR stall hits harder."
Wrong. A lower STR converter hits softer, not harder.
"A higher STR stall does well on the street because it is tighter (not hitting as hard)."
Wrong. A higher STR converter is better for the drag strip because it hits harder, not softer. If you check the STR of all the Yank racing converters, you'll see that they are all 2.5 or above and hard-hitting. The SY3500 I currently have in my car is a fairly soft-hitting converter with its 1.63 STR.
Last edited by XTrooper; Dec 5, 2004 at 08:33 AM.
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From: NE PA
Originally Posted by SportSide 5.3
Say you have a 3500 TCI.
It will flash near 3500rpm
but what will it brake to?
It will flash near 3500rpm
but what will it brake to?