1961 rambler roadster, new axle and trans...

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Active member
Feb 19, 2016
hi --

this isn't a new build, it's a continuous build, i guess... i built a roadster from a 1961 Rambler American, shaved off 800 lbs, it weighs 2250 with me and a half tank of gas in it... rambler six powered. been driving it over a year, reasonably hard. i made it to (vintage) rally, long desert road trips, work, etc. i've driven it from here in Los Angeles to Santa Fe NM and back, then Tucson and back, recently, through the Panamint and Death valleys.

here's the car...


on the way home i stripped the synchros off the stupid T96 transmission. again. if you've never heard of this trans, there's good reason, it's a total piece of crap, the major feature of, besides overdrive, is that it fits in the hole. i wasn't even shifting it hard, just 2 to 3 on the freeway.

the current project is to install a 1998 Mustang axle so that i can run the thoroughly modern (erm) T14 transmission... i have one, in great shape. adapting a T5 is "obvious", but the gears aren't a good match for this motor, and this chassis is really a 1956 Nash Rambler and has a number of weird features that make it more difficult (like no transmission crossmember) that complicate things.

the current rear axle is all Nash -- rambler folk call it the "big nut" axle because the rear end of the driveshaft attaches via spline and locking collar that requires 300 ft lbs applied with two comically large wrenches.

i'm ditching the big-nut rear for the Mustang part. gotta get it narrowed first (this week). that will put 2400 engine rpm at 64 mph in 3rd (1:1). i'll also get rear disc brakes, which to be honest, i don't need; i have hotrodded (ventilated) oversized (Gremlin) drum brakes up front, given the light weight they're fine. so a scarebird kits up front.

with the mustang rear the T14 slides in the hole. clutch and T96 shifter work as-is. the trans is the least of my worries (famous last words...)

the rear suspension is also custom. it used to be a leaf setup. it's now a rigid wishbone with panhard, air springs over each axle tube; geometry-wise, it's a torque tube, sort of like a single "truck arm" but the front end is a huge heim joint a few inches in front of the front U-joint. the one i'm running now has problems and so on the Mustang rear i'm improving it (and making it adjustable). zero axle wrap, very small pinion angle change, zero articulation binding, super lightweight, you can make 'em at home, etc. i don't know why it's so rare. i don't have good pics of the current setup but will make 'em for the new one.

so the current build is to get the axle narrowed, wishbone built, axle in place, transmission, brakes (hyd and park) in, driveshaft made.

i'll post pics as i go. work starts hopefully in the morning.
I love this whole thing! Someone ran a Rambler engine at Indy many years ago
mainly for the seven main bearings i believe. Welcome to the board. :cool:

Barney freakin' Navarro. the short story (from memory, likely damaged) is that some rich client contracted barney to build an Indy car. 1967? it was car #50. this was the era of wild innovation at Indy -- sideways diesels, turbines, etc -- and he went at it open-book -- the new at the time Rambler six (the 232, begat 258 begat 4.0... reigned for 40 years) barney said was the strongest inline six bottom end available. 7 mains, crazy huge webbing, etc. sleeved down to 181ci for the rules, ran a 199 (short stroke) crank.

engine #1 was a single turbo, Dellorto carb version, 550 hp. the second was twin turbo (!), hilborn mechanical FI.

so.... in 2005 Navarro auctioned off his shop, 5 mi. from me, in Glendale. i went cuz i knew of the rambler indy motor, but most folk were there for his famous flathead stuff. i just went to look.... the remaining twin-turbo motor, all prettied up on a stand, went for $11K, i think.

but out in the shop, in boxes of pieces, was all this Rambler stuff... the Ford guys didn't even see it. i got the whole pile for $500, and sold some axle parts immediately for $200, so i ended up with what turned out to be a partially complete test mule of the single turbo version.

here's some links to my site with pics of the pile i got. sold it all to a guy in Seattle, an import-scene turbo tuner shop, who is reconstructing the #50 car. i guess i should see how that's turning out...


all i have left is the short-stroke crank. it's an ordinary cast crank, but i assume it's in perfect balance and hand selected. the bearings ran dry of oil; from Barney's shop manager, on site at the auction, he said that this engine was being run at Buttonwillow testing, ran dry due to a problem. the pile included the crank carefully wrapped, and a big box of .010 over bearings so it looked like it was intended to be reused.
yanked the old guts out -- these chassis look like VW beetle pans underneath!

here's the current rigid wishbone system installed. it works OK but i made some fundamental mistakes. can't adjust the pinion angle (though it's within a degree i think) but worse, it's not quite square. the new design is adjustable. this one was simple though and i guess it's the prototype.


(suspension's dangling here; at ride height the panhard is parallel to the axle tubes.)

here's the components. since i don't have a rear crossmember (the crossmember holds up the back of the bellhousing, not the trans tail) i made a spider to position the wishbone's heim joint in line with and below the front U-joint. it needs little clearance since +/- 6" axle travel translates into 1/8" movement up front. and given the mechanical advantage the wishbone has the vertical torque is nothing. side to side torque, nothing. fore/aft, braking and acceleration, full axle mass and force. it's all overkill built anyway.


axle wrap torque does have decent leverage on the wishbone (it's 1.25"x0.120" wall DOM) and i suspect it bends a bit. it needs to be braced out a couple feet (or more substantially for actual high power) but with even 800 ft/lbs of axle torque, 4 feet away it's only 200 lbs of force. my new design has braces (that adjust pinion angle).

the panhard chassis anchor was a PITA. being a unibody there's no frame so i brought a tubular brace across from the other (floating) end so that i could keep the side force, well, side force, and not a lever trying to pry the panhard anchor off the "frame".


the fixed panhard anchor brace is the tube that's parallel in the pic above; the actual panhard here runs at an angle to the far backing plate. suspension is dangling and the camera angle is severe, it's quite parallel at ride height.

the air springs are right over the axle tube; simple as hell, lightest, and maximum anti-roll geometry.
a couple more pics of the "before", prototype wishbone rear.

here's a detail of the right (US passenger side) axle end, the spring axle pad below and the axle panhard mount stud to the right. the panhard mount bolts to the axle tube flange (grade 8 bolts) and takes all the lateral force; it's U-bolted to the axle tube, which should only get a small fraction of the car's lateral energy.


here's the notorious big nut. you need two 2-3/8" wrenches (which, if you search for on google, you get little tiny wrenches... not the three-foot monsters needed :)


i can't say that i'll really miss it, though it's cool to need to use the giant wrenches.

here's a couple pics of the spider, the places the wishbone heim joint below of and in front of the front U-joint. side view is easiest to see...


the transmission area is the busiest corner of the chassis; everything seems to converge here. but this pic, taken from behind and below, shows the U-joint, heim, the spider (braced upwards onto the floor pan, and forward to the rear motor crossmount), etc crisscrossed by the parking brake. home made brake system to the left.


the new trans, a long skinny tail housing where the fat overdrive and all it's solenoids butting outward, will be a lot cleaner. alas, no OD :-(
oh yeah, one last thing -- i found a nifty trick for putting a Stewart-Warner electronic speedo pickup sensor on a driveshaft -- !

the instructions say that it needs to be within 40 thousands or so for it to work, and there's no way this weird factory system is that stable.

so i epoxied two identical magnets onto the driveshaft -- big scary ones -- and the sensor works great TWO INCHES AWAY from the driveshaft!!! lol. end of tight clearance issues!

you can see the fat, black sensor (threaded) in the upper right of the picture above. can't see the magnets, but note the crazy huge distance.
movin' along, though not much to show -- the mustang axle is at Cooks Machinery Service getting narrowed; got the metal for the wishbone; got the clevises (clevii?) and rod ends etc from QA1. got the front disc brake kit from Scarebird, since the rears will be discs.

the mid-1970's T14 transmission (not the Jeep version; Rambler passenger car input shaft and tail housing) i was gambling on to be OK, is, mostly. the tip off the 3-2 lockout bar is broken off somehow, gotta figure out where to get one (or maybe weld it). bearings noisy. but gear teeth sharp edged, no peening nor overheat, no metal in the case, etc. whew! when things get this old, there's no telling what they've been through by the time you get 'em... got a rebuild kit coming from BEARINGKITS.COM.

took hours of scrubbing (three cleanings) to get the hard parts clean enough to inspect! that seems to be how my transmission projects go...

the last few weeks of silence was dealing with the last weeks of the school semester -- student reviews, thesis projects, etc -- but i wasn't doin' nuttin, i was planning, plotting, and ordering parts. all arrived, work has started.

this is a AMC/Rambler T14, internally identical to the Jeep trans (common, there) except it has a very long mainshaft and extended tail housing, and the side shifter bosses are drilled with conventional forks (the Jeep trans is top shifted). i used a Jeep rebuild kit, which is missing the correct cover gasket and shifter shaft O-rings, and output seal.


i got the T14 torn down, cleaned up, busted parts replaced, reassembled. as seems to be usual, after disassembly it took three full cleanings to get the parts inspectable. the caked on black tarry residue i'd not seen before.


i *almost* stuck the thing in without rebuilding, which would have been incredibly stupid. upon disassembly, besides the horrible crud, the bearings were noisy, and two 2-3 shift parts were broken. don't know how that would happen, maybe it was dropped in a way that jammed the lever or the car was in a crash. took a bit to find replacements.


look! i even remembered to not block the oil hole in the input shaft! this is my second transmission rebuild, before this one the T96, which is almost identical except about 3/4th scale. same genetic design...


so far so good. this was a plain old rebuild. tailshaft housing and bearing retainer installed of course, nto shown here. interestingly (to me, anyway) is that the bearing retainer has a T96 part number.

the next step is to hack the bellhousing to accommodate the two lower mounting ears of the T14; it's bolt-in-compatible with the T96 except for that. at the same time i need to switch to a different rear engine mount since the correct part is flatly unavailable. that's coming out great. later this week for that.
cluster gear installation tool

for this design Borg Warner manual trans, installing the cluster gear requires a tool to hold the rollers in place in the gear cluster as it's lowered into the case and it's shaft driven in. documentation calls for a particular diameter/length steel bar.

i had access to a lathe before the T96 rebuild i did years ago, but no such luck today (and the T96 tool is too short).

the tool is simply a rod or dowel of the correct diameter and length. it turns out, cheap M type household 1/2" copper plumbing copper pipe is nearly perfect -- a wee bit small diameter but it worked perfectly first try.

the tool wants to be .677" diameter, the copper tube is about .625 or so (guessing), and nice a soft and cheap and in my junkbox.
That's the great thing about manual transmissions. Most people can rebuild them at home.
I did a rebuild on mine as well.
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with the T14 out of the way for the moment, i get to move on to important matters!

the T14 fits into the bellhousing, same input shaft and pilot and bearing retainer hole and the two upper bolt holes align; but these earliest Ramblers the lower holes of the transmission pattern are not compatible with the "modern" (sic) 1960's! transmission. had to add that.

as it happens, the rear motor mounts haven't been available for decades (NOS rubber doesn't count) and one of mine is rotten. the front mounts are plentiful and common, they have some industrial application, i just bought some from RockAuto for 81 cents! seriously. so i made a Problem Solver that both provides the two lower trans holes and uses a pair of front mounts on the rear.



here it is more or less installed.


it is at this time that i realized that the engine and transmission is not centered in the chassis! i think it is true that i am the only fool to ever seriously mess with this chassis. the drivers side of the car has all these massive components: battery, starter, steering box, generator (HOLY CRAP ITS HEAVY), and the driver -- yet the springs left and right are the same, but in the "big car' Ramblers (10, 80 chassis; Classic and Ambassador) with the same situation, there was a compensatory different spring rate and height for left and right. but the 01 chassis (American; mine) same springs.

but only the manual transmission car is offset! the automatic car is centered! WTF!

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i also worked out the big chunks of the new rear suspension incorporating the Mustang axle. the design is a rigid wishbone, adjustable in all dimensions.

though not complete, this pic shows all of the important parts except the front heim joint and it's tubing, and the new spider to hold the heim about where the yoke comes out of the transmission. the basic geometry is complete though, since i'm replacing a previous (flawed) wishbone system.


though the previous simple single tube wishbone showed no sign of bending from axle-wrap forces, the new wishbone has a brace, which also allows for very straightforward adjustment of pinion angle, lacking in the previous one.


tomorrow i'll insert the trans into the bellhousing, position the axle assembly so i can setup the front heim joint and support spider, and get the clutch boxed up to ship to Tennessee Clutch and Supply for rebuilding.

i kept the factory 4-link bracketry on the axle tube, and extended it upwards, for the brace/adjustment link. it's a carefully carved piece of 3/16" cold-rolled steel with a hole for the upper heim. the horizontal edge of the addition will support the outboard edge of the air spring perch, not complete yet.
OK, the clutch is off to Tennessee Clutch & Supply for rebuilding. transmission installed to get everything else together.

got a new spider built and installed (unibody car, no transmission crossmember, so the spider positions the wishbone's front joint).


got the axle 99% kitted out -- wishbone and struts (pinion and geometry adjust) in place, painted and assembled except the front big joint. so far everything's been built on paper and out of the car, and today i placed the axle assembly under the car, got it in the correct location and sat the chassis down on the deflated air springs to check for overall clearance. obviously i won't drive like this but it's got to tolerate it, this is extreme lower bump. it all worked out great.



if you look closely you can see the white mark on the butt end of the spider's heim joint mounting plate. chassis center is to the left of the transmission output shaft, because the engine and transmission are offset to the passenger side about an inch.


i chopped out the previous panhard for the previous wishbone system; it was too close to the gear cover (the rambler axle is much smaller than the ford) and building that next.
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here's the rigid wishbone's guts. the wishbone effective length is nearly 70 inches (in a 100 inch wheelbase car!) so pinion angle change with rear suspension travel is pretty minimal. body could roll 20 degrees before it binds.


geometry-wise, it's great. imagine truck arms, except super long, and the front pivots touch in the middle. or a four-bar link, but the lower arms and upper arms are the same length and pivot at the same point.

the upper struts are swaged L and R threaded tubes from QA1.net. they adjust pinion angle. all four connections to the axle tube are via heims. the joints don't move when on the road. but the lower joints allow a small range of geometry adjust (1/4") to compensate for build error and they accommodate the odd angle that the wishbone meets the mounts. the strum heims are necessary because changing the pinion angle slightly tweaks the geometry and the strut-to-axle angle changes slightly and without joints it would add bending stress.
Running the risk of being accused of being an arm chair engineer, all of your heims are double sheer except the two top bar heims on top of the rear end.
They may never give you a problem but, would be better in double sheer.


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