Will GM 200r4 work with factory floor shift location?

[Treblig]

Here is one of the pics I promised. It shows the location (on the 2004R) at the center of the factory cross member. The silver line represent where the stock Mopar lower cross member (trans mount) would be. More pics and info later, gotta go!!!

Treblig

 

[Treblig]

These pics show how far back it is from the center of the factory mount to center of the 2004R mount. Very close to 4 3/8" - 4 7/16".
When I measured the distance from the front of the adapter to the tranny seal I got 27 9/16" but that can't be correct so I'll have to measure it again. My 2004R tranny housing plus the adapter should be more like 28 1/2" but I'll check tomorrow and make sure.
Either way the set-up that JBC426 is using measures out at 28 3/8" which about 1/8" shorter than mine is (should be). If all this is correct the adapter ring and Reid bell housing don't seem to save much on cutting the upper cross member. It only makes sense that it couldn't be much shorter because the bell housing has to contain enough space for the GM torque converter to exist.
There's no point in making assumptions so we'll just all have to wait and see. Lucky for JBC, he already knows where and how much he's going to have to cut and basically where the trans mount will be.
I did forget to measure the vertical distance from the factory mount surface to the 2004R mount surface so that if anybody else does try this they'll know where to put the mount horizontally and vertically relative to the factory mount.


treblig

 

[Woods74]

You drivin' yet?

 

[Treblig]

You drivin' yet?

HELL YES!!!!!!!!!! It drives like silk!!!!! As smooth as glass!!! Slicker than snot!!! And best of all that annoying "drone" sound is gone!!!! I thought it was my exhaust system and mufflers BUT NO!!! It was the RPM causing the drone. It shifted so nice I couldn't believe it. And it's so quite going down the highway that I have to "goose it" just to make sure the engine is running. I couldn't find one leak on any fitting!! I'm too surprised to be happy. I'm afraid if I celebrate too much the dream might end.:cheers::blob::burnout::toothy2::happy7:

SPEECHLESS>>>>>>>>>>>>.
Treblig

 

[Woods74]

Well, being as thorough as you've been, paid off. Rock on!

 

[Treblig]

In spite of all my pre-planning I still had a few things that bit me. But I've very happy with the results. Now all I need to do is get the 4:10 gears installed and really enjoy the car.

Treblig

 

[jbc426]

In spite of all my pre-planning I still had a few things that bit me. But I've very happy with the results. Now all I need to do is get the 4:10 gears installed and really enjoy the car.

Treblig

Dang, I'm happy for you Treblig!

What gears are in it now? I almost went 4.10's, but opted for some 3.91's because of the 2.76 first in the 200R4. I'm not sure what ratio that would be equal to using the 727's first gear ratio, which is around 2.50-to-1 or something.

Heck, the SCT Tuned 196K mile long block with 90 psi in the #2 cylinder 140'ish in the rest, 727 with mild stall converter, a smallish Hughes cam & 1100 valves springs I have in it now spun the rear 255 60R15 Radial TA tires with 3.23's out of hole at full throttle and chirped them into second a few feet at around 55- 60 mph.

Last month, I put some rather tall 275 60R15 Nitto Drag Radials and shhhh, some custom-fitted, summit slapper bars on the rear. Don't worry Mopar purists, I painted them flat black so you can't really see them. It hooks up hard now with 5 to 10 feet of spin with the current engine trans combo. Ride quality hasn't suffered either.

I'm sure with 3.91's, a 2.76 first gear, a 3000 stall converter and 500 something HP; It's going to annihilate the rear tires in first and second, which of course makes it significantly more fun to drive, especially on week long road trips with the .67 overdrive and lock-up converter.

As almost any Mopar guy can tell, this car needs a 408 stroker with around 500hp and 3.91's with an overdrive. It's a heavy car weighing around 3000 lbs! It's only running high 13's or low 14's with the worn out 5.9 EFI. Besides, it puffs out some blue smoke on the right side at full throttle. It's embarrassing!

The sun didn't cooperate to well for the pictures, but the tires fill the wheel wells without rubbing. I'll try to get a better shot of the rear later in the early evening when the lighting is better.

 

[Treblig]

Dang, I'm happy for you Treblig!

What gears are in it now? I almost went 4.10's, but opted for some 3.91's because of the 2.76 first in the 200R4. I'm not sure what ratio that would be equal to using the 727's first gear ratio, which is around 2.50-to-1 or something.

Heck, the SCT Tuned 196K mile long block with 90 psi in the #2 cylinder 140'ish in the rest, 727 with mild stall converter, a smallish Hughes cam & 1100 valves springs I have in it now spun the rear 255 60R15 Radial TA tires with 3.23's out of hole at full throttle and chirped them into second a few feet at around 55- 60 mph.

Last month, I put some rather tall 275 60R15 Nitto Drag Radials and shhhh, some custom-fitted, summit slapper bars on the rear. Don't worry Mopar purists, I painted them flat black so you can't really see them. It hooks up hard now with 5 to 10 feet of spin with the current engine trans combo. Ride quality hasn't suffered either.

I'm sure with 3.91's, a 2.76 first gear, a 3000 stall converter and 500 something HP; It's going to annihilate the rear tires in first and second, which of course makes it significantly more fun to drive, especially on week long road trips with the .67 overdrive and lock-up converter.

As almost any Mopar guy can tell, this car needs a 408 stroker with around 500hp and 3.91's with an overdrive. It's a heavy car weighing around 3000 lbs! It's only running high 13's or low 14's with the worn out 5.9 EFI. Besides, it puffs out some blue smoke on the right side at full throttle. It's embarrassing!

The sun didn't cooperate to well for the pictures, but the tires fill the wheel wells without rubbing. I'll try to get a better shot of the rear later in the early evening when the lighting is better.

To tell you the truth I honestly am not sure what I'm currently running for a rear gear. I know it's either 3.08 or 3.23 but I can't remember which. I have already purchased a new set of 4:10 Richmond gears for the Barracuda. BUT.....it ran so smooth and quiet on the highway with my current gears and the 2004R that I'm seriously considering going with 3:90s. Oh well, I'll decide in the next few weeks as I enjoy my new Barracuda. I'm running 295s on the rear (10" thread) with a Eaton posi and 12 bolt axles. The new torque converter (1800 max stall) worked great, I did notice that it won't quite start moving on it's own unless I give it just a little gas....PERFECT!!

Treblig

 

[Woods74]

This might help your question on gear selection; I'd advise get a few hundred RPM's inside your cams power-band at cruise and lockup, so as not to lug and get good fuel efficiency.

http://vexer.com/automotive-tools/speed-rpm-calculator

 

[Treblig]

This might help your question on gear selection; I'd advise get a few hundred RPM's inside your cams power-band at cruise and lockup, so as not to lug and get good fuel efficiency.

http://vexer.com/automotive-tools/speed-rpm-calculator

Pretty cool website. I totally agree with how to choose a gear!!. I have a non lockup converter so it makes things a little easier. I deliberately used a non lockup because a lock up converter sucks trans fluid pressure away from 4th gear. In fact, the only time the converter does lock up is when the tranny is in 4th gear, I believe it's designed that way. Since 4th gear is the weakest gear it tends to fails first. Losing any fluid pressure to the converter (so that it lock up) only decreases the life of the tranny because once 4th gear starts to fail (for lack of pressure) it puts trash in the system and then it's just a matter of time before the whole tranny is ruined. Everybody probably knows all this anyway!!

treblig

 

[jbc426]

Pretty cool website. I totally agree with how to choose a gear!!. I have a non lockup converter so it makes things a little easier. I deliberately used a non lockup because a lock up converter sucks trans fluid pressure away from 4th gear. In fact, the only time the converter does lock up is when the tranny is in 4th gear, I believe it's designed that way. Since 4th gear is the weakest gear it tends to fails first. Losing any fluid pressure to the converter (so that it lock up) only decreases the life of the tranny because once 4th gear starts to fail (for lack of pressure) it puts trash in the system and then it's just a matter of time before the whole tranny is ruined. Everybody probably knows all this anyway!!

treblig

Great point about the weak links in a stock 200R4. Choosing quality heavy duty components and beefing up the weak links in these transmission is critical.

Once the problem areas are addressed and upgraded with quality components, both the transmission and lock-up torque converters are very strong and reliable. Extreme Automatics has a 200R4 that's rated at 1000 hp. Precision Torque Converters offers a triple disc lock- up amongst many other HD features. They address the issue with the stock lock-up clutches by using 3 clutches instead of just one, and a host of other HD upgrades. It's not cheap, but it's money well spent if you are going to put some power through it.

Here's a screen shot about it. It describes exactly what you're talking about Treblig.

 

[Woods74]

Not sure what the concern is, most of the time you use lock-up is when crusing anyway, that's only 50-60HP, ain't like your towing a heavy load or slamming at the drags.

 

[Treblig]

Not sure what the concern is, most of the time you use lock-up is when crusing anyway, that's only 50-60HP, ain't like your towing a heavy load or slamming at the drags.

Yes...very true!! Your car is under a light load when you're in 4th gear. And if 4th gear is engaged and has the full force of the front pump there is no reason why it should slip. But it has been documented that in order for the torque converter to function (lock up) it must use the same fluid that is used to keep 4th gear engaged. This lock up function takes some fluid pressure away from 4th gear. It's not a BIG deal as 4 speed automatics will normally last a very long time when they are not abused and when they are properly maintained. But no matter how good you are to your AOD 4th gear will always last longer if it has the optimum amount of pressure required to keep the clutches positively engaged. It comes down to a matter of choice. Use a non lock up which creates more heat requiring the use of an extra trans cooler (and lose a 2 or 3 MPG). Or use a lock up converter accepting the fact that it will take some pressure out of the system which inadvertently decreases line pressure to 4th gear.
Its' a choice.

Treblig

 

[Woods74]

Tis true. I guess you could raise line pressure, or how much is fed to the clutches? In the a500, I know you can drill out the passages for better flow, how much was there in the first place, is the question eh? Hopefully a shift kit helps us all here. I don't believe lock-up is that big of a deal RPM or MPG wise. Quality converters closing the gap. Not knocking the choice, your the type of guy to think things through, just wondering.

 

[jbc426]

I understand it is an issue with an unmoddified 200rR4. In the right hands, these issues are easily overcome. As many know the Throttle Valve Cable adjustment is critical on these transmissions. Even the rate at which the cable is pulled in relation to how the throttle is opened is critical.

The pump issue is one of the major things addressed in a performance built 200R4. High performance pumps with a massive volume increase and the potential to supply the required pressure in any gear at throttle setting is part of what allows these transmissions to handle so much more power than stock. Of course it is only one of many things needed to beef them up.

Here's a list of what goes into all Extreme Automatic's 200R4's. The Stage 2 and Stage 3 versions take it even farther. Add a one-wire 12v hook-up, HD 3 clutch Precision Torque Converter, and the pressure loss and slippage problems you've mentioned no longer exist.

"All Extreme Automatics™ TH200-4Rs include:
◾Pump:
◾The EA™ Super Pump™ is the heart of the 2004R build.
◾The EA™ Super Pump™ is the heart of the 2004R/700R4/4L60E build.
◾We first start by parallel decking the pump halves to a perfect 90° center line of Stator.
◾We Machine lap to a fine finish and maximum of .001" Slide Clearance.
◾Pump Drains are drilled to releive Excess pressure on the pump seal.
◾We install a Teflon® coated bushing staked in place.
◾The pump is ported for maximum fluid flow.
◾The Max pressure circuit is enhanced to allow for a Max of 325 psi
◾A New Hardened Stator support is installed.
◾Matched Rotor and Slide assembly to keep Maximum Clearence to .001"
◾7 Vane Rotor used for Strength and Volume Except 4L60E.
◾The Pressure Regulator Modified to allow for accurate Pressure control and slightly increased Lube.
◾Pressure Regulator Spring is Variable Rate to allow for quick line pressure changes
◾Boost Valve Assemblies .500/.367 to compliment the Quick Ratio PR Spring
◾The EA™ Super Pump™ will supply up to 300 psi HOT with increased Volume earning the name Super Pump the best in the industry.
◾Internals
◾Direct Drum - Ground to ensure Roundness. Lube modification (Stage 2-3 Models) To Aid in cooling of the drum and band Lubrication.
◾L/R Center Support - Fitted with a Torrington® Bearing in lieu of Thrust washer to handle thrust load
◾Center Support - Pressed Apart and sealed. Teflon® Sealing Rings used to eliminate cross leaks. Machined for Torrington® Bearing OD Ring Gear (Stage 3 only)
◾Sun gear Shell - Hardened Sungear Shell installed all units.
◾Planets - All Planets are disassembled and rollers are replaced with Pins as Needed. New Race and wear washers are used in all three planets. (Stage 3 Only The pins are replaced with through hardened 300M pins with new race and wear washers welded in place.)
◾Sprags (Roller Clutch) - All Models are Fitted with new Borg Warner Sprag assemblies in OD and Low.(Stage 3 fitted with HD Chrysler Rear Roller Clutch. )
◾Bearings - Torrington® Bearing replaced through out unit.
◾Washers - New thrust washers All Units
◾Pump thrust - New AC Delco® pump thrust. ( Stage 3 is Torrington® Bearing)
◾EA Billet Forward Drum Shaft - ( Stage 2-3 only) The EA™ Forward drum shaft is made with 300M Aircraft quality steel. The shaft is machined then heat treated then finish ground to exact specification. This Hi strength shaft is then welded into the Forward drum basket.
◾Clutch
◾**** We Do Not use Clutch Lining made by Alto®****
◾Direct Friction - EA™ Exclusive Hi Energy Carbon. We are the only manufacture that has our own lining to handle Heat and Hi HP.
◾Forward friction - EA™ Hi Energy Carbon. We use a double wave plate to help prevent banging when shifting to drive.
◾Low/ Reverse Friction - EA Hi Energy Carbon
◾Overrun Friction - Borg Warner®
◾OD Friction - Borg Warner® 3 Clutch all Models
◾Steels - Micro Polished Raybestos Steels Used Threw out. We used polished steels as they aid in clutch application and remove heat from the clutch pack. We Never use Koleen steels.
◾Intermediate Band - EA™ Exclusive Hi Static Lining. We use a solid strap and have lined with a Blended Hi Static lining. This lining is not typically used in a shifting band but we found that it will hold more HP shift quicker than any other available lining. As mentioned, our band is a solid strap. The Popular Alto® wide band is 38.5 sq inch of apply area and band lugs do not go all the way across the band to apply the band evenly making good use of the 38.5 sq inch of apply area. They tend to curl up on the ends reducing apply area over time to less than 35 sq inch. Our Band is the std width and has 38.5 sq inch of apply area with lugs that go the width of the band so we are able to use all 38.5 sq inch. This makes for a band that does not wear out on the ends and slowly wear out the valuable direct drum.
◾Servo Assembly
◾“Size does matter” Our servo is a full 2.995" diameter on the apply side. We use a Dual Scarf on the apply side and lip seal on the release side. While one competitor has a similar size servo, its radically different. “Engineering Does Matter” Our competitor uses a 3 piece design. This design allows the pin to float within the apply piston and relies solely on the return spring to push the band pin to keep it tight against the piston. The servo and the pin move independently. A very delicate balance and in some cases can cause premature band failure. The EA Extreme Automatics™ 2004R Servo uses a one piece design. The design attaches the servo pin and piston assembly to move as one unit. No we have predictable controlled apply and release of the servo assembly. This creates perfect shift timing.
◾Valvebody (BRC)
◾The Brain of the EA™ 2004R is the BRC™. BRC™ simply means BR Calibrated. We took the most popular BR Valvebody more commonly know and exclusively used on the Buick Grand National and basically copied it. After hours on a test bench we were able to see the difference between the Hi Performance BR Valvebody and the standard VB used on most other passenger cars. We then went to work duplicating the performance. What we ended with a Vb that is easily produced with shift like Characteristics of the original Vb used on the Buick Grand National thus the Name BR Calibrated. This was a major step for EA. We became the first builder of the 2004R that did not require and expensive 2004R core from a Grand National or a Monte Carlo SS to build a reliable 2004R with performance shift qualities. We build and sell BRC™ valvebodies to some of the other 2004R builders to this day."


This is the reason I opted for a professionally built trans and a high quality lock-up converter. I just don't have all this specialized knowledge. I know its no guarantee, because anything can break, but it sure seemed like good insurance to me to buy quality components from guys with great reputations.

There is some WOT efficiency lost due to the lock-up converter, as opposed to the non-lock-up converters. If you are big into drag racing or never take long road trips, it's better to go with the non-lockup.

As Treblig eluded to, another thing that is critical to the life of these transmissions is to have the correct line pressure. Here is a cut and past screen shot from Extreme Automatics website. Notice the optimally, the pressure is higher in 3rd & 4th than in 1st & 2nd.

My builder also says a pressure gauge should be used to help verify proper TV Cable adjustment. There's a good PDF document on his website explaining how to do it.

 

[Trogdoor]

To Treblig---I never could have imagined when I ask the original question of "whether the floor linkage could be made to work with a 200r4" that it would turn into such a great thread. Thank you for a lot of us for making this so complete and detailed. I am at this point completely jealous that you have yours completed. Now I am looking forward to jbc426 reporting on his build using the powerglide bellhousing. I would like to report more progress on my own 68 Dart convertible but still am not rebuilding yet. I have though, at this point purchased a Buick Grand National 200r4 that I will be using when the time comes.
I do still have a lingering question. You have no doubt proven that the floor shift linkage can be re-engineered to work. My question is for us average Joe's without a lot of fabrication skills. (drum roll) Looking back would it be easier to use a cable linkage with the floor shifter? Would a cable be a little more forgiving on the flex and rotation of the driveline vs such short fixed linkage? Your thoughts would be appreciated. If I recall you had moments thinking about this as a backup but you were always able to engineer your way to a solution. Once again thank you for staying the course with both your pictures and explanations.

 

[Treblig]

To Treblig---I never could have imagined when I ask the original question of "whether the floor linkage could be made to work with a 200r4" that it would turn into such a great thread. Thank you for a lot of us for making this so complete and detailed. I am at this point completely jealous that you have yours completed. Now I am looking forward to jbc426 reporting on his build using the powerglide bellhousing. I would like to report more progress on my own 68 Dart convertible but still am not rebuilding yet. I have though, at this point purchased a Buick Grand National 200r4 that I will be using when the time comes.
I do still have a lingering question. You have no doubt proven that the floor shift linkage can be re-engineered to work. My question is for us average Joe's without a lot of fabrication skills. (drum roll) Looking back would it be easier to use a cable linkage with the floor shifter? Would a cable be a little more forgiving on the flex and rotation of the driveline vs such short fixed linkage? Your thoughts would be appreciated. If I recall you had moments thinking about this as a backup but you were always able to engineer your way to a solution. Once again thank you for staying the course with both your pictures and explanations.

You lucky dog....I couldn't find a GN 2004R after two years of looking when I was trying to get a tranny for overhaul!!! Had to settle for a regular one, but with the help of that great transmission shop, they upgraded it and it works beautifully!!!
To answer your question...YES, it would be easier and much more forgiving and faster if you used a cable shifter!! I did it my way for many reasons, one - I'm stubborn as hell, two - I really wanted to keep the original shifter stuff, three - I love a challenge, four - it really wasn't that hard actually. But I understand where you're coming from. I hope my thread and my posts make it easier for you and others and if you have any questions at all or need extra pics of any areas...just let me know and I'll help in any way I can. I could have easily competed the swap in 5 days (or less) if I had known what I now know.
Thanks for hanging in there with me and thanks for the encouragement along the way. The cable shift would be way easier, just make a good mounting point at the floor shifter, make sure you put it in the correct location (front/rear), make sure there are no sharp bends, and once you get the shifter installed check the amount of "throw" you get on the cable and pick the appropriate spot on the tranny selection lever (double and triple check). You'll also get a little better response in your shifting if you secure the cable every 2 or 3 feet so it doesn't move around when you shift. Watch out for the exhaust, it will melt the cable!!!!

Treblig

 

[jbc426]

Treblig, your post has become a part of a-body history. You are a tenacious man with great talent and drive...overdrive!!!

I know some people would just bypass the radiator tank and go straight to an aftermarket cooler, but these cooler lines also warm the transmission up to safe operating temperatures more quickly too. Of course, after running through the radiator, I plan on going to an external auxiliary trans cooler as well to drop the temp even lower prior to its return to the transmission.

My latest question involves the cooler lines. I get that Mother Mopar has the smallest cooler line fittings at 1/8" NPT with the flare to the 5/16 cooler lines, while Chevy and Ford use the 1/4 " NPT with the flare to the 5/16" cooler lines. These fittings are located both on the transmission and on the lower radiator tank.

Here's the question, if they all use the 5/16" cooler lines, (without regard to the restriction the 1.8" NPT fittings Mopar uses) what size is the inside diameter to the internal radiator cooler? It must be at least 5/16" as well, right?

In other words, it's the fittings that screw into the Mopar transmissions and radiator cooler that are the only sources of restriction. Is that true?

I called US Radiator, and they seem willing to sell me just the 1/4" NPT "Chevy/Ford" sized internal , lower radiator tank "cooler/heater" to swap out the one that came in my custom radiator I bought from them for my Magnum install. They sure do nice work there. I never liked the look of aluminum radiators in these old Mopars. I can get a local shop to pop the lower tank off, swap out the internal cooler to the upsized fittings and solder it all back up for a nominal price.

Also, did you end up drilling out your fittings to match the inside diameter of the 5/16" line? In your experience, did it or would it take too much strength away from the fitting to open the inside diameter that much?

I just went out and took these pic. I also used the back of a drill bit to measure the inside diameter of the cooler fittings that came on my 200R4. I then measured the bit with an electronic dial caliper and came up with .220"

I'm sure the inside diameter of the 5/16 lines used on Mopar/Chevy and Ford are all larger than that. I'm going to have to go back into your post and see what size the 1/8" Mopar fittings is. I know I saw it in one of your posts.

 

[jbc426]

And here's what these home made fittings look like after they've been cleaned up. Both picks show the larger GM tranny line installed. The small end is the 1/8" pipe fitting that screws into a 904 and into my '69 Barracuda radiator. For some reason the original Mopar fittings (1/8" pipe) had very small through holes which restrict flow. The male to male 1/8" pipe fittings I bought have much larger through holes (about 15 percent larger)...that's a lot when it comes to tranny oil flow. And I'm seriously thinking about increasing the 1/8" pipe through hole to the full size of the 5/16 GM trans lines (.252" ID). I would only have to enlarge the hole .015" more which should not effect the strength of the fitting but it would give me another 15-18 percent increase in flow. I know, I know...too many details, but who would have known the that Mopar fittings were so restrictive to flow???

For all you members who install larger tranny lines and trans coolers to help the tranny stay cool are working against the laws of physics if you don't install 1/8" pipe fittings with larger through holes. No matter how large your tranny lines are the front pump still has to force all the fluid through a tiny hole in the 1/8" fitting (.220") at the transmission and at the radiator. The technical term for the stock fitting is known as a "restriction".

treblig

Ohhhh, so the .220" holes are already on the fittings that came on my 200R4! If they are drilled out and opened up to the .252" inside diameter of the 5/16" cooler lines, will that still allow enough of the flare sealing surface to be effective at the fittings, or will it take away too much material at the seat of the flare making it be prone to leakage/failure? Your thoughts Treblig? I will have to pick some fittings up today and do some experimenting.

 

[Treblig]

Ohhhh, so the .220" holes are already on the fittings that came on my 200R4! If they are drilled out and opened up to the .252" inside diameter of the 5/16" cooler lines, will that still allow enough of the flare sealing surface to be effective at the fittings, or will it take away too much material at the seat of the flare making it be prone to leakage/failure? Your thoughts Treblig? I will have to pick some fittings up today and do some experimenting.

Mopar fitting through holes are smaller than current 1/8"" pipe fittings. The aftermarket 1/8" fitting they sell (now) have a larger through hole. I guess the fitting manufacturer's realized that they could increase the size of the through hole without decreasing the structural integrity of the fitting or maybe they've improved the brass alloy. So you can either have the radiator shop install the proper connection on the radiator (like another member did on his radiator, see previous posts) or you can make an adapter fitting like I did. I'm not really sure you could drill out the through hole in the 1/8" pipe fitting without weakening it. You can make the through hole bigger but when you go to tighten the fitting the larger through hole might cause the fitting to break somewhere in the threaded area because of the thinner wall. I didn't drill mine because the hole was so close to the right size I didn't think it would cause much of a restriction. I do know that the new fitting will help the flow quite a bit.
All of the dimensions for both fitting are in my previous posts. If the radiator man does permanently install the fitting (silver solder) then you could drill them out larger since you won't be torqueing on the to screw them into the radiator. Just remember to hold a wrench on the radiator fitting when you tighten the 5/16" line onto it so you don't twist it off. The 5/16" line requires more torque than the 1/8" pipe can handle.

Treblig

 

[jbc426]

Got it. I checked the actual dril bit sizes that match closest to the measurements and found a 7/32" (.220) drill is the current hole size for the fittings on the 200R4; and the 1/4" drill (.250") should be equal to the inside diameter of the 5/16" line size, right?

There is a significant difference between the two sizes, but I'm now lean toward the method you used, mating the two fittings, silver soldering them and then trying to carefully drill them out, first with the next size bigger drill and then with the 1/4" drill. I'll also drill out the current fittings on the 200R4 to the next size larger, because it's only .220" now. I'll make an extra set to experiment on and post the outcome. It will save the expense of up-sizing the lower radiator tank cooler.

Last year I bought an old school silver soldering kit, the real stuff, from a welding shop. I used it to solder a larger 3/8" return line into my fuel tank pick-up. A small spool of the solder and a small tube of the liquid flux was $50. It's like nothing sold in the hardware stores these days though. It's super strong!

Sorry for the lousy focus on the soldering example.

 

[Treblig]

I'm not at home at the moment but as soon as I get home I can check the extra parts for the sizes. It's been a few months since I worked on the fittings so I don't want to give you bad info.

Treblig

 

[Treblig]

All your measurements are pretty close to what I got. Drilling the GM tranny fitting (large fitting) shouldn't be an issue as there seems to be plenty of material to go out to .250". It's the 1/8" pipe that I worry about. But you can experiment and the worse that can happen is that the 1/8" pipe will snap when you try and torque into the radiator. If you use liquid Teflon on the threads you won't have to torque it as tight. You do know that the GM tranny lines are nothing more than brake lines from Orielly's, pretty common (another reason I switched).
In reality, to be precise, the Mopar fitting is too small (ID) on the inverted flare end. the 1/8" pipe end is much larger than the inverted flare end. But it makes no difference where the restriction is because you can't use the Mopar fitting with GM lines anyway. There's a formula out there some where that can tell you how much extra flow/volume you get when you increase the pipe diameter by X. I can't remember the formula but if memory serves me, keeping the pressure the same in both cases - -- if you increase the pipe diameter by 2 times your flow/volume increases 16 times!!!. I know that if you increase the diameter on from .220 to .250 it should increase flow/volume by at least 12-15 percent, which is a lot in a transmission cooling system.

treblig

 

[Treblig]

Here's that pesky formula...enjoy!!! If you double the diameter of a tube/pipe you increase the flow by 16 times!!! So every little bit helps tremendously!!

Treblig

 

[jbc426]

It dawned on me that I should give my transmission builder a call and run all this by him. He actually advised against enlarging the holes in the fittings beyond .220". He explained that if there is too much flow through the cooling component, the heat has less opportunity to be passed out of the coolers.
It makes sense, since only a portion of the pumped volume is sent out to the coolers at any given time.

I will be making fittings like you did for the radiator hook-ups, and enlarging them to match the .220" size that are on th200r4.

I call it ideal at that point.