BHP affect on stall rpm?
Thread Starter
TECH Addict
Joined: Jun 2005
Posts: 2,660
Likes: 14
From: England
BHP affect on stall rpm? Here's a question for those in the know.
The more hp/lb ft and engine makes the higher a torque converter will stall right?
Well what affect would there be on something like a 3600rpm stall if the car gains say an extra 100bhp?
Example:
Full bolt on LS1 making somewhere around 340-350rwhp. The stall was setup for this level of performance, and is rated at and stalls to 3600rpm.
Now the car under goes a h/c and know makes 440+rwhp and 410rwtq. How much higher would the same torque conveter stall too?
The stall inquestion would be a Fuddle SS or similar.
The more hp/lb ft and engine makes the higher a torque converter will stall right?
Well what affect would there be on something like a 3600rpm stall if the car gains say an extra 100bhp?
Example:
Full bolt on LS1 making somewhere around 340-350rwhp. The stall was setup for this level of performance, and is rated at and stalls to 3600rpm.
Now the car under goes a h/c and know makes 440+rwhp and 410rwtq. How much higher would the same torque conveter stall too?
The stall inquestion would be a Fuddle SS or similar.
It depends on the torque, not the horsepower of the engine. The torque is lower in the rpm range then the horsepower, and that is where the most amount of leverage will be seen by the converter. That converter (depending on the increased torque) may stall up and around 4000-4500.
Be weary of rated stall speeds, as some converter companies do not have the appropriate means of verifying the specs of converters. Some companies will base there specs on other "known" converters or what converter cores have shown to result in the past. To truely test a converter you need a converter dynomometer that can properly output the torque needed to verify the specs on the intended application.
Be weary of rated stall speeds, as some converter companies do not have the appropriate means of verifying the specs of converters. Some companies will base there specs on other "known" converters or what converter cores have shown to result in the past. To truely test a converter you need a converter dynomometer that can properly output the torque needed to verify the specs on the intended application.
Thread Starter
TECH Addict
Joined: Jun 2005
Posts: 2,660
Likes: 14
From: England
Cheers. I know it's a complex area, and I've read the info on Yanks website concerning dynometers.
Here's my dilema. I'm perfectly happy with a 3600rpm stall on a bolt on vehicle, I guess ~350rwtq.
But the car is not primerlily for dragging, more British B road bashing so I don't want too loose a converter. Also fuel prices suck over here so again I don't want anything too wild converter wise.
Now if by adding h/c (thinking along the lines of MS4 and PRC strage 1 heads) I think thru an auto ~440rwhp might be possible combined with all the other bolt ons (LTs, pulley, FAST 90/90, etc.) I've seen a similar setup on a manual making 480rwhp & 430rwtq.
But I don't really want to end up with my 3600rpm stall becoming a 4000 or 4400rpm stall due to the cam change. I'd prefer to keep it around 3600-3800rpm.
Here's my dilema. I'm perfectly happy with a 3600rpm stall on a bolt on vehicle, I guess ~350rwtq.
But the car is not primerlily for dragging, more British B road bashing so I don't want too loose a converter. Also fuel prices suck over here so again I don't want anything too wild converter wise.
Now if by adding h/c (thinking along the lines of MS4 and PRC strage 1 heads) I think thru an auto ~440rwhp might be possible combined with all the other bolt ons (LTs, pulley, FAST 90/90, etc.) I've seen a similar setup on a manual making 480rwhp & 430rwtq.
But I don't really want to end up with my 3600rpm stall becoming a 4000 or 4400rpm stall due to the cam change. I'd prefer to keep it around 3600-3800rpm.
You will have to look at the torque # at the stall rpm of 3600 if the heads and cam package yields less torque in that range the converter will stall less, more torque will be higher stall #, but will have a longer shift ext. as the power is pushed out in the upper rpm range.
The converter build design as to hydrodynamics will also be needed for this quess
The converter build design as to hydrodynamics will also be needed for this quess
Thread Starter
TECH Addict
Joined: Jun 2005
Posts: 2,660
Likes: 14
From: England
Cheers, well I might hold fire for a bit.
I don't actually have the converter yet, so I might wait until I have the h/c done also. It's too much of pain shipping across the pond to end up getting it wrong.
thanks for your help.
I don't actually have the converter yet, so I might wait until I have the h/c done also. It's too much of pain shipping across the pond to end up getting it wrong.
thanks for your help.
