2800 RPM Stall - Do you have it?
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2800 RPM Stall - Do you have it?
Is anyone else rocking one? Lextreme and Luxury Mods pulled off a miracle and have mine on the way in a huge rush (HUGE props!).
I know on most cars it's makes a pretty big difference in launch and acceleration - I'm N/A for the moment while I get the motor broken in and then will be adding the turbo setup to it.
I know on most cars it's makes a pretty big difference in launch and acceleration - I'm N/A for the moment while I get the motor broken in and then will be adding the turbo setup to it.
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For those of us in a car 8 hours a day, that left foot control isn't an option unless we want an artificial knee at the age of 30.
Mostly, I don't see it killing the fuel economy though being the stock rpm/tq curve from what I've seen starts slightly above 2800 RPm - if anything it might improve economy - especially when the turbo goes on and most of the power is made higher up. The stall on my Thunderbird SC upgraded netted better launches and better gas mileage.
Now, 3k or above stall, I could see killing the gas mileage
Mostly, I don't see it killing the fuel economy though being the stock rpm/tq curve from what I've seen starts slightly above 2800 RPm - if anything it might improve economy - especially when the turbo goes on and most of the power is made higher up. The stall on my Thunderbird SC upgraded netted better launches and better gas mileage.
Now, 3k or above stall, I could see killing the gas mileage
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I know it killed my Mustang MPG from an acceptable 16-18 to barely 10MPG in the city. It did nothing bad to highway mileage. A few of my Trail SS buddies went from miserable (12's) to intolerable as well with theirs.
Hope it works out, maybe the small displacement motors don't mind being spun faster just to get moving.
Hope it works out, maybe the small displacement motors don't mind being spun faster just to get moving.
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I've discovered a lot of people don't match their stall speeds to their setup.
Think about it like this, if you let off the clutch and drag the rpm's and have to hit the gas harder to get up to speed, you're wasting more gas.
Now, take the same theory, raise the rpm - now your motor has less rpm's to climb.
Basically, you're trying to match the optimum rpm for max efficiency. The majority of horse power and gas mileage loss in the torque converter stall from my research and application of trial and error.
Don't get me wrong, if you throw a 5k RPM stall on the car, it'll drive like crap and get horrible gas mileage.
I'm an I.T. Consultant, I drive everyday all day from business to business. 3200 RPM is pretty stout on a modular motor that makes most of it's power lower in the RPM range.
Think about it like this, if you let off the clutch and drag the rpm's and have to hit the gas harder to get up to speed, you're wasting more gas.
Now, take the same theory, raise the rpm - now your motor has less rpm's to climb.
Basically, you're trying to match the optimum rpm for max efficiency. The majority of horse power and gas mileage loss in the torque converter stall from my research and application of trial and error.
Don't get me wrong, if you throw a 5k RPM stall on the car, it'll drive like crap and get horrible gas mileage.
I'm an I.T. Consultant, I drive everyday all day from business to business. 3200 RPM is pretty stout on a modular motor that makes most of it's power lower in the RPM range.
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Definitely true.
However, I think that best applies to drag cars.
As a daily driver I don't think locking up early can be beat for fuel economy. Maybe getting the JZ into its powerband quicker will net better fuel economy. I would be interested in finding out.
The modular motor was a 4v so it's not terribly high compared to what most people upgrade to.
However, I think that best applies to drag cars.
As a daily driver I don't think locking up early can be beat for fuel economy. Maybe getting the JZ into its powerband quicker will net better fuel economy. I would be interested in finding out.
The modular motor was a 4v so it's not terribly high compared to what most people upgrade to.
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I was a big 4.6L fan back in the day before I moved to my Thunderbird SC and I remember the biggest gain in them was a higher stall converter quarter mile wise, they were just tanks in gas mileage either way lol.
I think it does have a lot to do with the motor not having as much power as it could for the weight. The converter still technically locks up 1:1 at higher speeds (which is why you still got good highway gas mileage), it's literally just like it's slipping the clutch just a little more to start off in a higher rpm. If the stall is already under rated from the factory then the car has to climb through the rpm's and fight the converter vs utilize it.
I think it does have a lot to do with the motor not having as much power as it could for the weight. The converter still technically locks up 1:1 at higher speeds (which is why you still got good highway gas mileage), it's literally just like it's slipping the clutch just a little more to start off in a higher rpm. If the stall is already under rated from the factory then the car has to climb through the rpm's and fight the converter vs utilize it.
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I haven't done anything else yet, I'll be bypassing the cooler on the radiator and running a cooler to the front of the car with an aux fan to keep the temps in check and look into an upgraded valve body.
I pulled the front half of the transmission (spare) apart to see if there was anything in there more complex than a normal one (clutch pack, etc) and there's not so if I need to upgrade them I'll look into that when the time comes however this transmission was freshly redone right before I got the car.
I pulled the front half of the transmission (spare) apart to see if there was anything in there more complex than a normal one (clutch pack, etc) and there's not so if I need to upgrade them I'll look into that when the time comes however this transmission was freshly redone right before I got the car.
#12
Just remember that a torque converter multiplies torque at speeds below the stall point, so you gain power to the wheels along with hitting the heart of the torque sooner. Power isn't free, thus the loss in mileage.
Also, a given converter's stall point will move higher with the more torque that is put into it, so if you go turbo your effective stall speed will be higher than what you see in NA form.
Also, a given converter's stall point will move higher with the more torque that is put into it, so if you go turbo your effective stall speed will be higher than what you see in NA form.
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Think about it like adding a light weight flywheel into a standard - you'll be reducing the rotating mass increasing efficiency of the drive train, not gaining horse power.
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Negative, you're just setting a launch speed for consistency - so if your stall rpm was too high I could see that helping but if it's matched properly launching at the max stall speed will always be beneficial.