I've got a brand new TKX t-5 tranny mated to the original flathead that I'm trying to get set in my 49 Merc. Using The factory motor mounts, with the engine and transmission set to -3.4°, I've discovered a clearance issue with the frame crossmember that the yolk and driveline pass through. Before I start making plans to cut up and modify the x frame, does anyone know of any other options, such as slightly shorter motor mounts that might help give me some space on the output shaft end of things? Has anyone here put a t5 on the original flat head in a 49 to 51 Merc? Thanks
I'm thinking that is pretty much standard procedure with transmissions that weren't designed to fit in that space from the get go. Plus that Ricky Racer shifter location is going to be back in the middle of the seat and require buckets rather than a comfy bench.
I thought they built that new transmission so the shifter can be reversed? It is definitely one of the longest trannies I have ever encountered in my travels. I think the OP is going to be doing some surgery to the transmission cross member.
I've sold quite a few T5 into 49-50 Merc conversions using my Cornhusker Rod & Custom kit and the S10 T5 trans with minimal problems but the TKX thing is a whole new ball game. Might need a tunnel in the top of the cross member and spring for the front mounted shifter?
Normally that shifter sits beside you where you can pretty well lay your hand on the knob with your arm straight down to the elbow or just slightly forward at the elbow and not have to reach to shift. A Ford T-5 puts the shifter at 19.5 inches from the mounting surface of the trans. S-10 T-5 puts it at 11.5 mounting surface. I went out and looked at my T87D 3 speed and it measured 5-1/2 from mount surface to shifter. Older photo with no ruler. That is just for comparison. Remembering that the 3 speed floor shift I put on the 3 speed overdrive transmission in my 51 Merc sat just in front of the seat cushion and I could probably have slid the seat up a notch or two If I had to.
That trans looks long but the shifter is 19.52 from the front mount surface . It's the extension on the shift rail that no doubt adds some strength and stability that adds the unwanted bulk.
Wait a second. I'm not sure I fully understand. Are you saying with things set at 3.4 degrees the real problem is that you can't get a Driveshaft in the tranny? You didn't mention anything about the shift handle position or seat issue, so I take that as irrelevant. Asking about physically shorter motor mounts makes me think you just want to drop the tail end of the gear box. If that's the case and you are mounting your motor with "STOCK" Merc water pumps and rubber biscuits, you have a rear mount issue regardless of what angle you have things mounted at. Your tranny output shaft is on the Stock centerline as the O.E. tranny was no matter the overall length and the driveshaft passed into and through and into the tail shaft just fine. I think you modified your rear mount crossmember and created the issue. Drop the rear mount and make the driveshaft go in as it did in stock form.
Not sure what you mean by "Ricky Racer" as that's the factory shifter from Tremec. This tranny allows for 2 other shifter locations forwards of its current location, so there shouldn't be any issues with seat interference. Correct. The tranny has 2 more forward shifter locations besides where its at. And Yes, I'm thinking I will have some surgery to do. In the pictures the engine and tranny are sitting at -3.4 degrees which puts the output shaft end way to close to the top of the frame section. If I tilt everything down to get enough clearance for the yoke the motor and tranny will be more like -6 degrees or more. Incidentally, the carb to intake surface on my Offy manifold is also at a - 3.4 degree angle, which is why I thought everything should also be -3.4, to keep the carbs level, and since the prevailing wisdom of motor and tranny angles is usually around 3 degrees. My question about the motor mounts was more of a hail Mary option before cutting up the frame. I thought if the entire motor and tranny could drop down an inch or so, keeping the same angle would have probably given me enough clearance... but I also know that could have created issues with steering linkage, but one thing at a time. I am using '49 correct water pumps and motor mounts (square box style, not round disc style) A scholar and a gentleman! Thank you. (I used the correct spelling above.) In a moment of "I'm an idiot" clarity, I just realized I didn't think about the fact that the TKX is almost 6" longer than the stock tranny, and that's where my clearance issues are coming from!
Not sure I'm much help as I swapped an S10 T5 mounted to an Oldsmobile. As such I did not have an issue with trans length, however did need to design a new rear trans crossmember mount to get it aligned through the frame ... Would you mind sharing your brake booster/master cylinder set up? Thanks, Ron
Remove the rear mount and set the height for clearances needed.[with a jack] Measure the gap between the trans mount pad and the crossmember ,and measure the height of the rear mount. Do some math. Then French the rear crossmember so mount sits lower down inside it
I have no idea where they actually come from (China most likely). I got mine from here years ago. I've seen the exact same thing sold by many, many other places. You can search 1949-51 Mercury brake booster on the googles for price comparisons. https://www.performanceonline.com/4...TmwJ-3-SkHrUkvxej0G-TTwKcEYIASfauMYcaZgkgEkiM
My concern is that your degrees are not relevant to factory chassis to motor numbers. In factory form the Crankshaft centerline and trans mainshaft centerline fits in place on your chassis without interference to the frame bracket you have issues with. You are working with a Frame and chassis with no weight on it. Are you sure you have Factory Ground profile where it would be in a completed vehicle so motor centerline is as it should be. I think you're fighting a battle that doesn't exist. Set your trans tailshaft so it centers in the opening of the X member as Factory and move on.
Total length does not have anything to do with centerline to Chassis ground profile. This degree number your working with is only relevant to Pinion angle.
Oddly I was thinking a little more about your project and was wondering. Where are you getting your ground level or the Zero degrees from off the bare frame?
How would shorter motor mounts help in the situation ? Any reason you can't rework the transmission mount ?
I believe he's trying to do a vertical drop on his 3.4 degree angle and get his tailshaft lower in the driveline opening so not to have to cut the frame. That's how I read it.
If "-3.4°" means down on the back, I wouldn't worry about dropping the trans mount a little more. 5 degrees is common on later stuff.
I don’t have anything to add other than suggesting you make sure all of your clutch and pressure plate stuff actually clears that speedway adapter. VERY common for guys to realize much further down the road that it all hits and the inside needs clearanced.
I should note this car is a bagged car. At this point, I am only dry fitting everything because I knew I would have to fabricate a new tranny mount cross member and then have to have the motor and trans set before I could finalize the rear end and pinion angle. Right now, it's on the ground with just motor weight with bags aired up to a give an approx. ride height of 6". This I know, I just didn't realize when initially eyeballing the problem that the new tranny was so much longer than the factory one. I think if this new tranny was the same length, and allowed the yoke and u-joint to sit in front of the driveline opening, it probably wouldn't have been an issue, or at least not as much of one. I measured my distance from the ground to frame bottom in the front and back of the frame and used a digital angle finder with zero degree reference off the frame bottom and checked my angle on the tranny top and the block. Correct! If I could vertically drop the entire motor tranny assembly an inch or so (give or take) keeping the same -3.4*, I think that would give me enough yoke/u-joint clearance. Thanx! I'll double check and be aware of that! Appreciate it!
Being bagged the only concern is having things below the scrub line. I'm sure you're keeping an eye on that. I remember when my Merc was stock it had a large C shaped spacer between the waterpump mount ear and the top of the rubber biscuit. What happens to pan clearance if you eliminate those?
Another issue if dropping the motor lower is the cross shaft for clutch linkage. How much misalignment can it take before you have travel issues with it. In fact I'd install it now and check the alignment and travel. It could be possible the bellhousing cross shaft is a little high as it sets.
Looking at stock mounts right now...... Either, slice and dice the K-member, OR, the same for the stock mounts..... This isn't a paint by numbers deal what so ever.....Something has to give. There is NO definitive answer.....If the engine and clutch deal jive, then its k member time....... The chassis will remain the same slammed.......Only setting up the rear will come into effect=pinion angle. It all depends..........
If the front of the engine is on the stock mounts; why can't you run the drive shaft thru the same hole the stock shaft fit thru. Guess Ford's OEM engine angle is good.
Yea, I'm keeping everything above the scrub line. The stock '49 mounts are actually basically a square block. The mounts your talking about are for the 50 and 51's. I'm looking at the style as a possible option, as well as the universal street rod round puck styles. And then you gotta go throw a monkey wrench into the gears of progress by pointing out that little nugget!!!! It's actually a really good point that I hadn't factored in up till now. And after just going out to look at tings.... not much if any. I'll add that to the problem list... maybe a hydraulic clutch will solve that issue. As mentioned somewhere above, with the engine and tranny set at -3.4 degrees, and because the T5 is about 4-5" longer than factory, the slip yoke will hit the top plate of the X crossmember. In the factory format, the yoke and u-joint is in front of the driveline tunnel opening. The T5 will place them squarely in the "tunnel", and to create enough clearance, I would have to drop the tranny end a fare bit more, to almost -6 or -7 degrees and that will then create a gap between the motor mounts and water pumps not allowing them to sit flush. I get it, it "should" all be the same centerline, but with the longer tail section on the tranny is what's messing everything up.
I wouldn't go anywhere near a Hyd clutch unit if I were working with what you are. In fact, I would install that cross shaft and make sure it aligns with the frame mount and the release arm in the adapter next. If it's running uphill to the adapter, I'd be dropping the tail end of the gear box till the cross shaft was correct. That in itself might cure your issue. More info for ya. I also have a 50 Merc. I've owned it since I was in High School (dang that was a long time ago) and it's currently going through another big change. This time I'm installing a 392 Hemi. with an overdrive Torqueflight. I can tell you that package is longer than your Motor and T-5. My slip joint and U-Joint are inside that X and my unit is sitting at factory profile to the Frame. This tranny is a freekin Monster! I know this gear box wouldn't work in your case. That pan is mega deep and is only 1/2" below the bottom of the Frame rails.
In the first place you don't have a T5, you have a TKX. You have a 500 hp transmission with a 100 hp engine. A T5 is shorter, narrower and and lighter. Drop the back of the transmission down. I have use as much as 9 degrees down when needed. Mill the carb mounting flange if it makes you feel better, By the way, you can't lay frame on a 49 Merc, you lay X member. The frame is still an inch off the ground when the X menber hits
hello pleasewill it not be doing you a right favor in the long term I.E. the rear axle will deffo be coming up in the vehicle by 'some' or if you like, if the motor and trans location stock is 'x' if you affix the rear axle into the vehicle at 'x' -4'' you want to fit that where it is
TKX is way overkill for this. But you got it so run it. You will never hurt it. Dimensionally this is the same as a T5 except the main case is smaller. The gearsets load from the front rather than the top. I have a '32 Ford Sedan with a strong but stock 221 Flathead and I would love to put the '93 Mustang 5.0 T5 I have behind it. But I know to do so I would have to at least cut or modify the OEM cross member. It's a sacrifice you will have to make for the modern transmission.
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