Caprice2002

hi
ive read that TC doesnt increase HP but it actioly might decrease it
anyway
how much does the TC *worth* in HP??
ex:
lets say a car with 100% stock engine 5.7 gen3
and another car with same engine + 3500 TC
they are racing 1/2 mile ..
how much HP does the stock car need to get the finish line at the same time as the TC car??

DeepBlueZ

torque converters can sometimes decrease the measured horsepower on a dyno just because they slip a little more. my car only made 314 rwhp unlocked with a very inefficient TCS converter in it....locked up, 337 rwhp. with a stock converter locked and unlocked numbers would be much closer to eachother since the converter doesnt slip as much when unlocked.

there's really no point in dynoing a car after a TC install...you may gain some, you may lose some depending on your setup and what you're switching from. from my personal experience a 3500ish stall converter will PROBABLY knock about 4-6 tenths off a 1/4 mile ET. this of course is provided the stalled car has TRACTION. a street tire to street tire race between the two cars you mention would still be very close because the TC equipped car would be pedaling real hard off the line to try and get a handle on the traction situation but at the same time the STOCK TC car would suffer slightly from the lack of a high shift extension that keeps a motor like the gen3 (which makes the best use of its power up high) in its powerband all the way down the track....

in short its a tradeoff, traction becomes a problem with a torque converter with street tires but on a good set of drag radials or ET streets, the TC car will likely win by half a second or more...as for how much HP it would take to overcome this, its tough to tell, there are a lot of variables.

Caprice2002

sorry for this stupid question but i have to ask
"will PROBABLY knock about 4-6 tenths off a 1/4 mile ET"
lets say its 4 tenth.. does it mean that if stock car ET is 10 secs,
then the TC car ET would be
10 - 10 * 0.4 = 6 secs??
thanks

gator's 99TA

iTrader: (2)

No. if a car runs 10 second 1/4 mile and a convertor knocks of 4 tenths, you could run a 9.6 sec 1/4 mile.

BigPlanTransAm

and just what "stock" car are you talking about that runs 10's?
anyway, a general rule of thumb for 11-14(or so) sec cars is 10hp = .1 and 1mph. so if a converter gives you about .5 gain in the 1/4, the car without the converter would need about 50 more hp.

Caprice2002

10 sec just an easy example
50 hp thats a very large good number