Gonna put a 3.4 in a Nash Metropolitan!

[3.4NashMet]

I rebuilt my '58 Metropolitan starting in 2009 starting from a rusty hulk and doing all body, paint, interior and mechanical work. No telling how many hours I have in her, but it is a fun hobby. There is nothing like the Met for attracting attention. If only they would run as good as they look.

To this quest, I put in the drivetrain and suspension from a RWD 1980 Toyota Corolla SR5
It made the car run like an 80's 4 banger production sports / family import, which is modest fun. The handling was greatly improved, body roll was reduced, the disc brakes made it safe, the extra HP and 5 gears instead of three on the tree made it fun to run instead of driving an antique. But the Toyota was worn out when I bought it and more worn out after 3 years of having fun (interpret: tearing up the streets).
So, after much thought, I am putting a 3.4 from a 1995 Firebird in. I know I will have to deal with many sensors with the swap, but I think I will like the SFI and quieter, smoother power this will give over the 1800cc 4cyl, while returning as good MPG.
Thus far, the engines are out and the engine bay is being cleaned up and the rack and pinion is being transplanted to the Met.
I plan on learning a lot as I go.
Wish me luck.
I will be asking questions.

[Purple pit]

There was an early Corolla build here at one time. He got busy and we have not heard from him. Then there was a nice MGB build with a 3.4. That is pretty much done and is doing well. Know that because I got to ride in that one. It would be nice to have those guys show up and help out. Still, all you have to do is ask, someone should chime in.


The car looks great, looking forward to watching this build.

[neophile_17]

Car looks awesome!

You may want to look at the later heads as they are aluminum (3400 as they are commonly called of which there are pre and post 2000). They will save weight and perform better in every measurable way. They will require other modifications to support them though. This is the start of the rabbit hole that leads to a build instead of OEM motor swap. Swapping the RWD accessories onto a stock 3400 motor is also a good option if you want to stick with a close to OEM motor. Welcome and best of luck!

Sam

[3.4NashMet]

Today, I trial fitted the 3.4 in the Little Metropolitan. It fit! Because the hood rounds up in the middle (unlike the MG), I will have room for the intake. I had to move the steering box out and put in a rack and pinion that steers from the front of the axle. I was able to swing the Toyota struts 180 dg and use the (shortened) rack from the Firebird. I do not need power steering, and may move A/C and Alternator locations. I still need to select transmission and trailpiece for correct shifter location. The 6.38" Toyota may not handle the increased HP, even if I put in a Supra posi pumpkin (which will fit). That will come later.
Right now, fabricating motor mounts, finish up rack install, and bumping back some of the firewall for that left bank that is offset to the rear.
But check it out, it fits!
Stoked.
Considering aluminum heads to save weight. 160 stock HP is enough. I do not need more in this 2100# car. I will fit the components then work on rebuilding the motor, then get guages and sensors and computer to work well. I am really encouraged that this will all really fit.


The little Met is smiling again. I may use the teeth rather than the regular grille, now that there will be 3X the original HP under the hood.

[Purple pit]

That happened quick! Almost looks like there is enough room for the engine to rock side to side. So you may not need solid engine mounts?

[3.4NashMet]

I will use rubber cushioned motor mounts, either from the Firebird or the ones I altered from the Toyota. Rubber mounting reduces the noise inside the car. Front to back positioning, height, and firewall trimming are the next projects. I may have to get my transmission to get these located properly. So next post may be a while. I am semi-retired, so I can take all day on the project if I want to. And at this point, I want to. My wife says "don't finish it too fast, or you will have to find another project". Well, there is nothing like success to fuel enthusiasm. There is a HUGE gap between lowering a stripped down motor in the engine bay and driving it down the street. but it will be a fun journey.

[Guest]

You may want to look at using different accessory brackets, like those from an S10, which are far less bulky than the 3.4 F-body ones you have. Earlier F-body may be similar to S-series as well.

You can also go custom with the brackets.

First in my S-10 build, The Franken60, that I used a combination of stock 1988 S-10 brackets (power steering) a modified air pump bracket (lower alternator mount) and a custom upper alternator mount/tensioner mount, but could be made from a modified stock alternator mount.



Next up is the 240Z build, where I used the same S-10 front cover, and tensioner mount, since I had them left over from my S-10, but made a whole new alternator mount, to place the alternator where I did. This idea might work best for your Met, due to only really needing water pump and alternator.



Just to give you a couple ideas on how to change up the accessory locations and belt routing.

[Purple pit]

Good to hear on the mounts, cuts down on the vibration too. This build is going to be watched. These things take time, think it may take longer than she thinks.

Have you had any thoughts about springs in the front? Like something stronger to take the weight of the 60 degree. Hell I don't even know what a Met has up front, never looked under one. Seen a few in my time. Some on the road and most at local shows years back.

[3.4NashMet]

I checked on mounts today. I will be using some from the earlier Toyota swap I did a few years back. I need to find the right transmission and cut some firewall before welding the mounts on the crossmember.
I will need to modify front brackets to drive just three essential items; the alternator, water pump, and A/C. Without the alternator, the car dies. without the water pump, the engine gets too hot. Without the A/C in MO, I get too hot and die. A/C HAS to fit. I think I will put the alt up high on the driver's side, and the A/C on the opposite side.
About heavier springs: The springs (struts) in the Metropolitan are from a car that weighed about 400# more than the Metropolitan. I did an engine swap a few years ago, including suspension. When I put it all together and set it outside on level pavement this is what I saw:

It looked like a gasser without the engine. With the engine it still was not right. (pic 2) I learned about spring compression rates. We took out 1/2 loop and lowered the lower spring perch to get the ride height right (pic 4) To answer your question, I have heavier springs in it than the original. The original had equal wishbones with saggy soft springs. (pic 3). I have torsion bar / strut suspension with anti-sway bar and disc brakes.
The V6 sets back further in the engine bay, which may transfer some weight to the rear.
I put in 15" rear tires to raise rear axle ratio and get the back about 1" higher than the front (which has 13" tires)

We will see how this motor makes the car sit, but I am confident the springs and struts are matched to the increased weight, which is only about 100# more than the 4 cyl (and twice the HP). Thanks for asking, though.

[Purple pit]

The Midwest is a strange place. You must have heat and AC, with a range of -10-115F there is no way around it. Then there is the oh so fun 20+/- change in 24 hours or less.

Thanks for the photos. It sure makes it easy to see what you are talking about on the height. Torsion bar....thought that would sneak in. Man that is one huge upgrade that has been done to the front end. Did Nash even offer a sway? Disk brakes was something in that time most didn't know of. Four wheel drums..........feel lucky that I've never had to drive a car that had them.

If you are happy with the springs that is great. Was just going to give you a link to a place online that does custom or there is a shop not to far from me that does them too. A friend had that shop do some custom leafs for a 67 Camaro which they did a good job on. They also do coils at any size, length or rate.

[3.4NashMet]

A little more progress on swapping the 3.4 into a little Nash Metropolitan.
I got the engine and transmission mounts tacked in. They will be strengthened and fully welded next week, but the engine and transmission are resting where they ought. I had to chomp the engine crossmember a lot, due to the fact that the 3.4 is a rear sump and the Toyota engine and crossmember were front sump.
The Camero/Firebird have the engine sitting back for I presume better weight distribution. I think it is back further than the original engine, and the shifter is back about 4" from the last swap I did.
I had to open the tunnel a little to push up the tranny to level. I will close this with Firebird hump.


When I was getting the trans ready for mounting, I took off this: What is it? Do I need it? I am figuring some kinda harmonic balancer.
Lots of things I will need to do. Locate a rear axle and narrow it. Lighten the flywheel. Put in exhaust. Wire it all up. Figure larger radiator and its install.
But I am having fun and enjoying the work.
Dana

[Purple pit]

Photo one has the balancer/damper with some wood clamped to it. #5 is a mount of some sort. Not sure where it goes. Left side bolts to the frame/body(or trans), center has the rubber inside and the right side has two studs to bolt to something. My guess is a torque arm mount. The arm that goes from the rear axle to the trans. My 83 Z28 had a solid mount that almost always sheared the single bolt on the rear mount of the early 700r4's transmission.

[3.4NashMet]

Question: I would like LSD rear axle. I have the remainder of a '95 Bird, with the GU5 rear axle, being 3.23 ratio. I do not want to change the ratio, just have limited slip. I have to narrow the rear axle and have shoe brakes on the one I have presently, which is more than adequate to stop my 2200# car. I can cut the tube and put on new ends if I know how to find them. I am thinking just swap out carrier bearing with a Limited Slip of the same ratio would be good. I did the research, but am not sure how to find one in the junkyard. What are the applications or numbers for a swap? I do not need anything hefty. I am just working with a stock 3.4 with 5 spd.

[Guest]

If you were thinking of using a LSD carrier and the gear from another axle, stop now. The gears (ring and pinion) are made as matched sets and can not be swapped around, ESPECIALLY after they've been run in. Just because two sets may both be the same ratio and from the same manufacturer does not mean you can swap each part of the gears with each other.

You can however swap the the carrier itself, retaining your original ring gear. Make sure you get the right carrier for your gears. I don't think 3.23s came in anything other than a 3 series thickness, but you can get 3.08s in either a 2 series carrier thickness or a 3 series carrier thickness. Do some research on the 3.23 to make sure they were only ever a 3 series thickness.

You will need a jig in order to shorten the axle. The jig keeps everything in line so that the the angle between the diff and the axle tube end is minor or non existent. The shorter the axle is, the more paramount it is that the axle tubes be perfectly in line with the diff.

[3.4NashMet]

I have fabricated my brackets for the A/C, tensioner, and alternator. I will find a shorter belt to run. Functional is now, pretty comes later. The A/C compressor is close to the exhaust manifold, but with head sheilding, it will be OK. The alt power post is close to the valve cover or hose, but it will clear it. May have to shorten the post for safety.
Next I want to tackle the wiring.
I am stripping out the wires that I need to make the engine run. I will be locating the computer on the driver's side near the firewall, so I cannot use anyones ready made harness. I have looked for a post concerning what circuits I need to manage the engine and what ones I can turn off, but I can not find the post again.
Remember, my car is a '58 and is not set up for a computer. I need to power the computer for the engine. I am going to run my own sensors to oil pressure and water temp. I have my A/C switches and relays and fan controls.
Perhaps others have done a switch to a non-computer car, and can tell me what I need to retain of the 95 Firebird 3.4 SFI (manual trans) sensors to make this MetroBird fly.