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Whats decent at the wheels horsepower and torque

I assume at least 20-25% drop at the wheels with an auto, compared to crank.
So I would say a nice 400, making 400 crank hp, would have around 300 whp, depending on how good the converter is.
Damn the automatic take so much horsepower 100 I wonder if you could do anything to the automatic so we'll take less horsepower but thank you for this this is what I was looking for I guess my goal will to be in the 300
 
Damn the automatic take so much horsepower 100 I wonder if you could do anything to the automatic so we'll take less horsepower but thank you for this this is what I was looking for I guess my goal will to be in the 300
What they did back in the day was replace the converter with a clutch.
 
Damn the automatic take so much horsepower 100 I wonder if you could do anything to the automatic so we'll take less horsepower but thank you for this this is what I was looking for I guess my goal will to be in the 300
There's lots than can be done inside an automatic transmission to reduce parasitic loss, but it's all very expensive, and intended for a racing application. But a stick car will lose 10-15% too. Everything turning from the engine back uses horsepower, plus most engine dynos don't hang everything needed on the engine for street use.
Between the fan, water pump, alternator, internal trans friction, u-joints, rearend gears,(some rearends eat more power than others) axle bearings, and tire slippage, a hundred or more horspower can disappear easily. Then add in the slip of the converter, and the hospower lost in an auto (the bigger and stronger the trans, the more power it eats) and a bunch of power can disappear between an engine dyno and a chassis dyno.
 
I have seen some stuff that shows a torque converter has a positive effect on the power curve that offsets the loss of efficiency.
 
Well you came to the right place, some of the brightest mopar minds reside here.
Yeah…. Along with some brave dudes that don’t know much but jump in and figure it out along the way!
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I agree with some of the guys here, in that what's considered "decent" power is very subjective.
'My opinion' is, for a 60s car "decent" RWHP is anything north of 400. That's enough for a fun day at the track (if so inclined) with the right combo and non purpose-built racecar, and enough get you in plenty of trouble on the street......or worse.

Give this a read; it's an oldie but goodie and was obviously before the days of "boost this and boost that".
Mopar 440 Engine Power Upgrade - Mopar Muscle Magazine
 
I agree with some of the guys here, in that what's considered "decent" power is very subjective.
'My opinion' is, for a 60s car "decent" RWHP is anything north of 400. That's enough for a fun day at the track (if so inclined) with the right combo and non purpose-built racecar, and enough get you in plenty of trouble on the street......or worse.

Give this a read; it's an oldie but goodie and was obviously before the days of "boost this and boost that".
Mopar 440 Engine Power Upgrade - Mopar Muscle Magazine
Thanks I will read it
 
Same experience as KD. My car is a 68 Sport Satellite. Built a 451 big block with Eddy RPM Heads and intake, mild cam, tri-Y headers, 727 auto with 2200 stall converter. Tuned and dyno'd 391 HP 523 ft-lb torque at rear wheels. Novice driver best of 1/4 mile time 12.80 at sea level. That's great torque, but a bit lower HP than I expected. Seat of pants driving it feels snappy at WOT, but normal driving feels like less power than I expected. Most other mopar guys who drive my car tell me it runs and drives great and to just be satisfied, but then they themselves go ahead and rebuild their already 650 HP street car motor to make 900 HP. If they had my motor they would be re-doing it to get the power up for sure. More power costs more money though!

With an automatic, I feel like for a street car I'd like another 100 hp bump at the wheels. For me that would require tearing the motor down and installing new pistons and cam. Like others have said (and KD has done), putting the same motor paired with a manual trans will really wake things up and let you live in the fun torque band more of the time. There's also something to be said for lightening up the front end as much as possible (aluminum water pump, rad, etc).

My first version of this 440 with the 4.15" crank turned 369 HP at 5400 rpms.
It had 10.8 compression, the MP 509 cam, Edelbrock heads with stock rocker arms, an Edelbrock Performer RPM intake, Demon 850 carb, 2" headers and electronic ignition. I had a 3000 stall converter in the 727 and 4.10 gears. I sure thought my rear wheel HP would be more than 369. Even if you add 25% to that to account for "gross HP at the crank, I would have still been below 1 HP per inch. I hear that many people are disappointed with their dyno results.
Who knows where I am now with lower compression and a bigger cam.


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1:10 power to weight ratio is a good start. 400 rear wheel HP in a 4,000 pound car, or 300 HP in a 3,000 pound car
 
Make the owner feel REAL good . Factor in about 55% drive train loss. 700 crank horsepower!


Sure Mr dyno operator , lie to all your clients to make em feel better.
 
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