Posted By: VernMotor
More 727 questions oil feed holes - 02/14/10 05:33 PM
What size should I Drill this feed hole out to ?
More 727 questions oil feed holes
Posted By: WILD BILL
Re: More 727 questions oil feed holes - 02/14/10 06:14 PM
What's the reasonig behind enlarging it? 
Posted By: dartman366
Re: More 727 questions oil feed holes - 02/14/10 06:45 PM
don't know on that hole but make sure you blend the hole into the outer groove. any question's come see me. 
Posted By: VernMotor
Re: More 727 questions oil feed holes - 02/14/10 07:00 PM
I beleve you are talking about this.
That is not the hole I am showing. The pic I have up is one thats been drilled already.It is one of John K pics.The hole I am showing is from the pump to feed/lube the the front clutchs. I think ..
That is not the hole I am showing. The pic I have up is one thats been drilled already.It is one of John K pics.The hole I am showing is from the pump to feed/lube the the front clutchs. I think ..
Posted By: dartman366
Re: More 727 questions oil feed holes - 02/14/10 07:45 PM
yes I am. 
Posted By: DusterW2
Re: More 727 questions oil feed holes - 02/14/10 08:05 PM
The hole sprays oil on the front clutches. B&M Trans Kit instructions say to open hole to 3/32" ~ 0.090". Original hole size is 0.060" or less. The later model 727s do not have this hole, and the clutches get lube thru a different circuit.
John
John
Posted By: VernMotor
Re: More 727 questions oil feed holes - 02/14/10 08:10 PM
Thank you again !
Posted By: turbobitt
Re: More 727 questions oil feed holes - 02/14/10 08:23 PM
This feed hole will supply lube oil to the front clutch bushing. I wouldn't enlarge it. To much oil in the front clutch area will just make it more difficult for the clutches to squeeze it out during apply.
FWIW, I've been starting to add this feed hole on my later pumps that don't have it for more direct/beter bushing lube oil.
Allan G.
FWIW, I've been starting to add this feed hole on my later pumps that don't have it for more direct/beter bushing lube oil.
Allan G.
Posted By: John_Kunkel
Re: More 727 questions oil feed holes - 02/14/10 09:49 PM
Nearly everybody in the business enlarges that hole, some go as large as 1/8" which is the size in the pic in the OP.
The clearance between the discs dictates how much fluid will have to be squeezed out on application, the idea is to increase to volume of the flow through the discs for cooling.
Posted By: turbobitt
Re: More 727 questions oil feed holes - 02/15/10 01:44 AM
Quote:
Nearly everybody in the business enlarges that hole, some go as large as 1/8" which is the size in the pic in the OP.
So do we blindly follow the masses and just do it without understanding the reasoning ? Is it needed ? Do we have any data to support this modification ?
Quote:
The clearance between the discs dictates how much fluid will have to be squeezed out on application, the idea is to increase to volume of the flow through the discs for cooling.
Clutch material and groove vs. no groove among other things will also impact this.
Not trying to be a PITA or wise a$$ but I've seen to many modifications done simply because the other guy has done them. Would be very interested in any real world data to support this modification.
Allan G.
Posted By: 440Jim
Re: More 727 questions oil feed holes - 02/15/10 03:28 PM
I like this mod to lube the sprag and associated parts. 1/16" dia hole added.
Posted By: 440Jim
Re: More 727 questions oil feed holes - 02/15/10 03:30 PM
And here are some reference dimensions to help locate the lube hole.
Posted By: VernMotor
Re: More 727 questions oil feed holes - 02/15/10 03:44 PM
Yes I aready got that done Jim Thanks
Posted By: John_Kunkel
Re: More 727 questions oil feed holes - 02/15/10 07:16 PM
Quote:
So do we blindly follow the masses and just do it without understanding the reasoning ? Is it needed ? Do we have any data to support this modification ?
How many of the mods that you perform are fairly standard?
As to the reasoning think about this, in 1st gear the front cluth drum turns 80% of input shaft speed but in the opposite direction; so the surface speed of the discs is 180% of input shaft speed; lots of drag there. The extra volume of fluid helps keep the surfaces well lubricated and helps cooling especially at the higher rpm's that race cars turn.
Quote:
Clutch material and groove vs. no groove among other things will also impact this.
Maybe so but the fact remains that fluids don't compress, so the actual volume of fluid that is present between the discs is the same no matter how much extra volume passes between them and that extra volume that needs to be "squeezed out" seems to be your original arguing point.
Posted By: turbobitt
Re: More 727 questions oil feed holes - 02/15/10 07:45 PM
Quote:Quote:
So do we blindly follow the masses and just do it without understanding the reasoning ? Is it needed ? Do we have any data to support this modification ?
How many of the mods that you perform are fairly standard?
As to the reasoning think about this, in 1st gear the front cluth drum turns 80% of input shaft speed but in the opposite direction; so the surface speed of the discs is 180% of input shaft speed; lots of drag there. The extra volume of fluid helps keep the surfaces well lubricated and helps cooling especially at the higher rpm's that race cars turn.Quote:
Clutch material and groove vs. no groove among other things will also impact this.
Maybe so but the fact remains that fluids don't compress, so the actual volume of fluid that is present between the discs is the same no matter how much extra volume passes between them and that extra volume that needs to be "squeezed out" seems to be your original arguing point.
So if there is already a full volume of fluid in this area , then why make this hole bigger ? Again, looking for some hard data.
My interest is from the fact that I have had issues witht he direct drum bushing getting worn or producing fine material in the oil. I have had this issue on a few of my own transmissions with the common thing being that they both have extra clutches and therfore may have increased the mass of the drum assembly. I have added this hole to my later style pumps to see if it will help in delivering lube oil to this area. I have not inspected it since I done this modification so I have no data to share but at least I'm attempting to back it up with an A/B testing.
In this case with a transmission with the hole already there I would argue that if it was OK from the factory then why increase it ? If you have any data(not aome elaborate theory)to share then please post it as I'm looking to learn.
Quote:
How many of the mods that you perform are fairly standard?
Most, if not all the modifications I've done are based on my own testing, or at least from trial and error. Have I used shift kits before and done there modifications ? of course.. BUT I take the time to understand the efects of those modifications. I'm not claiming to invent anything or be on the cutting edge of anything but would like to have a full understanding of any particular modification. I've spent many hours on my valve bodies, as well as my TH400 stuff trying to understand and map out the fluid flow and its effects.
Allan G.
Posted By: John_Kunkel
Re: More 727 questions oil feed holes - 02/16/10 01:06 AM
Quote:
So if there is already a full volume of fluid in this area , then why make this hole bigger ? Again, looking for some hard data.
How do you know that the factory size hole supplies "full volume" in a performance situation. Got hard data?
Quote:
Most, if not all the modifications I've done are based on my own testing, or at least from trial and error.
How do you "test", got a dyno?
Why do you question this mod? What's the possible downside of enlarging the hole?
Posted By: QWK_ENUF
Re: More 727 questions oil feed holes - 02/16/10 01:14 AM
Posted By: dartman366
Re: More 727 questions oil feed holes - 02/16/10 01:25 AM
Quote:I agree, this is the kind of post we can all learn from, so let's not let it die an early death, sometime's the way thing's are written can be taken the wrong way, when in reality it may of not been intended that way.
anybody see this post
https://board.moparts.org/ubbthreads/show...e=0#Post5795766
I used to have problem's with 904's not holding up,,I tried a lot of these mod's and now I have some pretty good success with them after reading the thing's that John Kunkle, John Cope, and 440Jim have written and applied to my home built tranny's
Posted By: 440Jim
Re: More 727 questions oil feed holes - 02/16/10 01:51 AM
FWIW, (take it or leave it),
I learned a lot from John Kunkel and John Russo (DusterW2). But I always read and make my own decisions. He is usually right...
I like the added fluid to cool the front (direct) clutch disks in my race car. I also believe this mod helps increase the flow.
I learned a lot from John Kunkel and John Russo (DusterW2). But I always read and make my own decisions. He is usually right...
I like the added fluid to cool the front (direct) clutch disks in my race car. I also believe this mod helps increase the flow.
Posted By: VernMotor
Re: More 727 questions oil feed holes - 02/16/10 02:01 AM
And fluid to them holes would come from the hole I am talking about drilling so you have all them holes and space to fill with a .060 hole. this deal is almost like splash oiling. Am I thinking about this right ?
Posted By: 440Jim
Re: More 727 questions oil feed holes - 02/16/10 02:02 AM
Yea, that is how I see it.
The pressure fed hole (enlarge to 3/32 to 1/8) will flow more fluid than the centrifugal flung holes in my last post. But I see them going together.
The pressure fed hole (enlarge to 3/32 to 1/8) will flow more fluid than the centrifugal flung holes in my last post. But I see them going together.
Posted By: QWK_ENUF
Re: More 727 questions oil feed holes - 02/16/10 02:03 AM
I'm pretty fortunate as i live right by John Cope and i have not been kicked out of his shop yet and my trans gets any and all mods he thinks are needed'
oh ya parts too
and there is a lot of good info on here except for the " how to paint your block " by wild bill koffel
oh ya parts too
and there is a lot of good info on here except for the " how to paint your block " by wild bill koffel
Posted By: dartman366
Re: More 727 questions oil feed holes - 02/16/10 02:15 AM
Quote:
a lot of good info on here except for the " how to paint your block " by wild bill koffel
Posted By: VernMotor
Re: More 727 questions oil feed holes - 02/16/10 02:20 AM
I buy all my trans parts from John ( CRT ) and we have talk on the phone about this some ..But I hate to burn all his time up..I build my own trans and I only have to do it every 3 or so years. I am a auto tech do drivable/elec work have been for 30 years. I use to work in a trans shop but that's been 20 years ago.so I have to think long and hard about things when I work on one. I was hoping I and other's could learn from this...We need a good trans tech thread every now and then. just because some of us do it diff does not mean it wrong. I just to hear what you do and why YOU think its a good idea.
Posted By: VernMotor
Re: More 727 questions oil feed holes - 02/16/10 02:33 AM
I just check them holes in the clutch basket( not sure what else to call it ) and they are .157 so I have drill them out before.
Posted By: turbobitt
Re: More 727 questions oil feed holes - 02/16/10 03:19 AM
Quote:
How do you know that the factory size hole supplies "full volume" in a performance situation. Got hard data?
Was asking for your data since you have a firm opinion on this modification. Why are you taking this the wrong way ? Not questioning your ability or knowledge on these transmission but looking for real world data. Did you ever see an improvment due to this mod ?? Please share your findings, I will be interested.
Quote:
How do you "test", got a dyno?
In my case with the bearing material in the oil, it will be trial and error. No dyno.
Quote:
Why do you question this mod? What's the possible downside of enlarging the hole?
I question this mod since it looks to have the same missconseption like the acumulator spring. Why have all this oil and excess windage in and around the drum if its not needed ?? This oil is supplied from the converter circuit so ask yourself, do you want hot oil that hasn't circulated out of the cooler circuit in and around the clutches you claim are keeping cool ?? There are reasons I'm asking these questions. Just want to understand the effects of these mods...
Allan G.
Posted By: @#$%&*!
Re: More 727 questions oil feed holes - 02/16/10 04:10 AM
I don't know about you, but I spend about 1.5 seconds in first gear. That's not much time to make heat.
Quote:
As to the reasoning think about this, in 1st gear the front cluth drum turns 80% of input shaft speed but in the opposite direction; so the surface speed of the discs is 180% of input shaft speed; lots of drag there. The extra volume of fluid helps keep the surfaces well lubricated and helps cooling especially at the higher rpm's that race cars turn.
Posted By: MR_P_BODY
Re: More 727 questions oil feed holes - 02/16/10 04:24 AM
Quote:
I don't know about you, but I spend about 1.5 seconds in first gear. That's not much time to make heat.
But if your on the trans brake you make about 100
degrees for every second your on the brake at max
torque.... just something else to think about
Posted By: John_Kunkel
Re: More 727 questions oil feed holes - 02/16/10 05:32 AM
Quote:
I question this mod since it looks to have the same missconseption like the acumulator spring.
Not even in the same ball park, the removal of the accumulator spring can be proven to be of no benefit but enlarging the hole is debatable.
Quote:
Why have all this oil and excess windage in and around the drum if its not needed ??
Once again you state for a fact that this mod overloads the front drum with lube when it might actually be providing the amount of fluid that the drum actually needs but the factory cut short.
Quote:
This oil is supplied from the converter circuit so ask yourself, do you want hot oil that hasn't circulated out of the cooler circuit in and around the clutches you claim are keeping cool ??
But the fluid is tapped off before it enters the converter and gets heated, check the fluid flow diagrams.
Quote:
There are reasons I'm asking these questions.
In the absence of any proof that enlarging the hole is detrimental to the function/life of the transmission I ask again.....why NOT do it. Just like the sprag lube mod shown above, the factory didn't feel that it's necessary to increase the lube to the sprag but sprag failure is one of the most common maladies in the TF; even after knowing this the factory has never addressed the problem.
Posted By: turbobitt
Re: More 727 questions oil feed holes - 02/16/10 01:00 PM
Quote:
But the fluid is tapped off before it enters the converter and gets heated, check the fluid flow diagrams.
No need for me to look at the fluid diagrams, just look at the circuit itself. The drilling goes through the support and grabs oil from the converter feed directly in front of the pump. So you think it doesn't get hot in this area ??
I still havent seen anyone give any conclusive evidence that this is needed. If someone noticed a differece in durability once they done this then I'm sold. For now nothing said has provided that supporting evidence. Am I wrong ?
The oil drilling in the rear of the case for the sprag makes sense to me and I'm sure there is more supporting evidence that it is needed BUT would like to keep this debate on the front feed hole like the original post was inquiring about.
Allan G.
Posted By: atoetly
Re: More 727 questions oil feed holes - 02/16/10 01:55 PM
Quote:Quote:I agree, this is the kind of post we can all learn from, so let's not let it die an early death, sometime's the way thing's are written can be taken the wrong way, when in reality it may of not been intended that way.
anybody see this post
https://board.moparts.org/ubbthreads/show...e=0#Post5795766
I used to have problem's with 904's not holding up,,I tried a lot of these mod's and now I have some pretty good success with them after reading the thing's that John Kunkle, John Cope, and 440Jim have written and applied to my home built tranny's
I agree If it were not for these people my stuff would have been burned up and not working nearly as well as it does. I print up all their mods and keep them in a binder at home for reference.
Posted By: John_Kunkel
Re: More 727 questions oil feed holes - 02/16/10 09:45 PM
Quote:
No need for me to look at the fluid diagrams, just look at the circuit itself. The drilling goes through the support and grabs oil from the converter feed directly in front of the pump. So you think it doesn't get hot in this area ??
Sure, all of the fluid is "hot" but my comment was in reply to your comment that the clutch lube is "hot oil that hasn't circulated out of the cooler circuit". The cooler circuit is fluid leaving the converter, the clutch lube is fluid entering the converter.
Quote:
I still havent seen anyone give any conclusive evidence that this is needed.
Well, if you feel that way my advice would be to NOT perform this mod. I feel that there is no downside and it takes less than a minute to perform and it costs zilch.
Posted By: turbobitt
Re: More 727 questions oil feed holes - 02/17/10 03:10 AM
Quote:Quote:
No need for me to look at the fluid diagrams, just look at the circuit itself. The drilling goes through the support and grabs oil from the converter feed directly in front of the pump. So you think it doesn't get hot in this area ??
Sure, all of the fluid is "hot" but my comment was in reply to your comment that the clutch lube is "hot oil that hasn't circulated out of the cooler circuit". The cooler circuit is fluid leaving the converter, the clutch lube is fluid entering the converter.Quote:
I still havent seen anyone give any conclusive evidence that this is needed.
Well, if you feel that way my advice would be to NOT perform this mod. I feel that there is no downside and it takes less than a minute to perform and it costs zilch.
John, Don't take this as a personal attack. Just wanted a healthy debate. In my opinion, I think it makes sense that there is an oil feed in this location. I really don't think that the size is that critical. I'm hoping that my own testing will shed some light on this.
Allan G.
Posted By: @#$%&*!
Re: More 727 questions oil feed holes - 02/17/10 03:30 AM
Quote:Quote:
I don't know about you, but I spend about 1.5 seconds in first gear. That's not much time to make heat.
But if your on the trans brake you make about 100
degrees for every second your on the brake at max
torque.... just something else to think about
We were talking about the front clutch pack, not the torque converter. I certainly hope the front clutch parts aren't turning when on the T-brake.
Posted By: John_Kunkel
Re: More 727 questions oil feed holes - 02/17/10 08:44 PM
Quote:
John, Don't take this as a personal attack. Just wanted a healthy debate. In my opinion, I think it makes sense that there is an oil feed in this location. I really don't think that the size is that critical. I'm hoping that my own testing will shed some light on this.
Allan G.
No offense taken, I understand that the burden of proof lies with the one making the claim (me) so you have every right to question it as long it's based on sound reasoning.
Unless you have some sort of lab I don't see what kind of "testing" would prove the point one way or the other.