will putting a sprag in my spragless convert lower heat

psycho6cyl

Ponies Are For Lil Girls
As the title says will putting a sprag in my converter lower heat? any down sides running one on the street? figure 99% street car with long trips. or will i have to go back to a conventional lock up trans and converter? thanks
 

David Husek

Turbo Buick Performance
As the title says will putting a sprag in my converter lower heat? any down sides running one on the street? figure 99% street car with long trips. or will i have to go back to a conventional lock up trans and converter? thanks
YES, it will lower heat. No downsides as long as a HD sprag or a quality diode is installed. For the best cooling, a lock-up has an advantage.
 

robzombie

Well-Known Member
A converter with a sprag will run cooler.

With the intended use you state you probably should go back to a LU anyways.

The cost is negligible and you would save money on fuel on your long trips.

It would pay for itself in no time.
 

psycho6cyl

Ponies Are For Lil Girls
Thx for replies. Really not trying to spend more money going back to a lock up. Do I regret it,yes but just trying to make best of situation. I wonder if I incorporate the factory cooler with my derale remote mount will it help? I'm seeing 220 just highway driving if I harass it 230 and once I hit NYC it's climbing quickly past 240
 

robzombie

Well-Known Member
Thx for replies. Really not trying to spend more money going back to a lock up. Do I regret it,yes but just trying to make best of situation. I wonder if I incorporate the factory cooler with my derale remote mount will it help? I'm seeing 220 just highway driving if I harass it 230 and once I hit NYC it's climbing quickly past 240

With those temps you'll be rebuilding the trans soon enough anyways.

Spend a little now or a total rebuild will be in the near future.

Even a trans cooler with a dedicated fan on it you may only drop down to the high 190* range which still isn't that great.

You can try and see what you end up with for a temp and go from there. Ideally you want it in the 170* range with 190*/200* ok for hard hits but with a fast recovery time.

I run a L/U and have a fan mounted cooler and maintain 170/180* temps in the 100* heat of summer.

The cooler you can get the temps the longer it will live, simple as that.
 

fastblackracing

Well-Known Member
YES, it will lower heat. No downsides as long as a HD sprag or a quality diode is installed. For the best cooling, a lock-up has an advantage.

Dave, not to hijack the thread but where would you recomend measuring the fluid temp at? Would it be different spot
for a 200 vs. 400?
I have the hughs cast pan and am thinking of putting a gm temp sensor in one of sides and using the xfi to monitor trans temp.
I am also thinking about drilling an tapping the pan in 2 spots 3/8 npt and using an electric fuel pump, small Holley or whatever and using it as a circultion pump to a remote cooler so that the trans pump does not have the extra load on it.

Wuld appreciate your input on this, Thanks, FB.
 

psycho6cyl

Ponies Are For Lil Girls
I'm measuring it right before the fluid goes into trans from the cooler. Right near the fitting out of trans. They say it should be pan but I can't see it making it that much of a difference
 

psycho6cyl

Ponies Are For Lil Girls
With those temps you'll be rebuilding the trans soon enough anyways.

Spend a little now or a total rebuild will be in the near future.

Even a trans cooler with a dedicated fan on it you may only drop down to the high 190* range which still isn't that great.

You can try and see what you end up with for a temp and go from there. Ideally you want it in the 170* range with 190*/200* ok for hard hits but with a fast recovery time.

I run a L/U and have a fan mounted cooler and maintain 170/180* temps in the 100* heat of summer.

The cooler you can get the temps the longer it will live, simple as that.

Those temps are w a dedicated trans cooler and fan..
 

fastblackracing

Well-Known Member
I'm measuring it right before the fluid goes into trans from the cooler. Right near the fitting out of trans. They say it should be pan but I can't see it making it that much of a difference
Thanks for the info....so you have a tee fitting near the factory brass return line fitting?
 

David Husek

Turbo Buick Performance
Dave, not to hijack the thread but where would you recomend measuring the fluid temp at? Would it be different spot
for a 200 vs. 400?
I have the hughs cast pan and am thinking of putting a gm temp sensor in one of sides and using the xfi to monitor trans temp.
I am also thinking about drilling an tapping the pan in 2 spots 3/8 npt and using an electric fuel pump, small Holley or whatever and using it as a circultion pump to a remote cooler so that the trans pump does not have the extra load on it.

Wuld appreciate your input on this, Thanks, FB.
I have seen temp readings done before aux cooler, after aux cooler and in the pan. The way I recommend it is to put the sensor in the pan. You need to know the overall temp of the fluid as this is what is circulated. For proper cooling I recommend that the radiator be used along with a 30000 gvw cooler with direct air flow. Behind an intercooler is fine. If the radiator is not an option, an aux cooler with a fan can be used with a thermostat. Adding the extra pump and cooler may cause air bubbles in the oil. I cant say if this will work or not. Remember being too cold is as bad as being too hot.
 

psycho6cyl

Ponies Are For Lil Girls
Thanks for the info....so you have a tee fitting near the factory brass return line fitting?
I did all a/n fittings and hoses. So its the metric to an adapter to an by npt threads into a copper t put sensor and continued w fittings. I'll snap a pic later if I can
 

Dusty Bradford

Well-Known Member
I've seen a sprag drop temps 15-20 degrees. It's not a huge difference but at the point your at, it don't hurt. Its best to monitor temp in the pan for a direct comparison.
 

434nova

Active Member
Bison video of him driving to the track through the mountains shows its possible to have a spragless converter on a daily driver and keep Temps reasonable.
 

Dusty Bradford

Well-Known Member
Bison video of him driving to the track through the mountains shows its possible to have a spragless converter on a daily driver and keep Temps reasonable.

I'm not sure if there are variations in cooler flow in different transmissions or what but I've seen identical converters with very similar cooler set ups vary a lot in temps.
 

Otto J

Well-Known Member
I agree with Dave. If it's a street driven car DO NOT bypass the cooler in the radiator.
The water typically in the radiator is less than 190* so you are in essence cooling your trans fluid down to 190 then passing through your auxiliary cooler will drop it further.
This is what I have found works the best.
 

David Husek

Turbo Buick Performance
What happens with temps in a spragless converter is dependent on how the vehicle is driven. If the driver drives with a steady throttle going down the road, the temps will be lower. If the driver is on and off the throttle, basically unable to regulate speed by a constant throttle opening, the trans temps will be much higher. So that being said, with a spragless converter, any time converter flow is changed, such as deceleration or acceleration, fluid does not have an easy path thru the stator and the fluid is heated by the restricted path. When you have a sprag or diode, the path of oil flow is easier to pass thru the stator not heating the fluid as much. I recommend a sprag or diode for any street driven vehicle as to save your trans from the extreme temps. 200-4R builds are not cheap. Every twenty degrees of fluid temperature rise cuts the life expectancy in half and robs the power handling in a 200-4R transmission. Better fluids do help a lot, but still doesn't stop frictions from glazing, seal and rubber parts from getting brittle at constant higher temps. Make sure to have more than adequate cooling.
 

robzombie

Well-Known Member
Bison video of him driving to the track through the mountains shows its possible to have a spragless converter on a daily driver and keep Temps reasonable.

Possible yes, is it possible to survive if you jump off a bridge and fall 200ft. and live? Yes.

Does that mean we should all just follow the leader and jump off a bridge because one man survived??
 
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