My '85 MGM, "Maisa"

[Tynnerstroem]

I recall that I struggled to fine accurately sized tires too for mine. I forget, but I think I went with 215 65, or 205 70 or some such which doesn't look weird to me and the speedo readings are perfect if the Waze app is to be believed. However they are all season blackwalls though. Regardless, love that car season has arrived to our corner of the world! Met an 88-91 Colony Park this morning in the city, you just love to see our cars out and about in traffic.

[Arquemann]

I recall that I struggled to fine accurately sized tires too for mine. I forget, but I think I went with 215 65, or 205 70 or some such which doesn't look weird to me and the speedo readings are perfect if the Waze app is to be believed. However they are all season blackwalls though. Regardless, love that car season has arrived to our corner of the world! Met an 88-91 Colony Park this morning in the city, you just love to see our cars out and about in traffic.

215/65 and 205/70 might look quite small, considering the factory 215/70 can look a bit small aswell, depending on the viewing angle. 205/75 has a better selection than the 215/70, but it's not great either.
I have an interesting "feature" of the speedo reading slower than actual, and not just a little. According to a GPS, the speedo shows about 5-7% slow (with 225/70 in the rear, which is only 1.9% larger than factory 215/70). The 205/75 is almost in the middle of the two, which is why I'd really prefer the original size so it'd actually make a difference in the speedo error.

[Tiggie]

Have you tried a speedometer gear with 1 less tooth? My speedometer is dead on with a gray 18T gear, 3.27, and 225/70.

It seems no me modern tires have shrunk in width for a given size.

[Arquemann]

Have you tried a speedometer gear with 1 less tooth? My speedometer is dead on with a gray 18T gear, 3.27, and 225/70.

It seems no me modern tires have shrunk in width for a given size.

Weird thing is that everything seems to be completely factory and unmolested. Speedo cable has probably never been off the trans, I have no clue what drive gear it has, or what the driven gear should be stock. No idea how much 1 tooth up or down affects things and if anything is even available close to whatever teeth gear it's got inside. Factory 3.08 gears.

I've now ordered a 3rd set of 215/70s, maybe these ones won't get cancelled.

[Arquemann]

Maisa is back home!



Retrieval was pretty uneventful, took a bit longer to start than usual, but did fire up just fine when it eventually did so. She's running kinda lean though, idles okay still but light throttle feels quite sluggish. I guess I get to go through all the vacuum caps and lines again. I haven't had any issues from evaporated petrol leaving any crap in the carb and I don't want to pull off the carb.
Topped up the tank with about 20 liters of fresh stuff, completely forgetting that the filler neck seal leaks...

Fluid leaks are pretty minor, I was pleasantly surprised after driving the car out of it's spot.
A single thumbnail-sized spot of ATF, nothing else

[GMUE03]

Pretty impressed with the lack of sweat from the underside after sitting for some time. I know my 89’ will leave maybe half an ounce of Valvolines finest on the driveway after sitting for a week. I guess that’s the difference between an original engine and a freshly overhauled one.

[87GrandMarq]

It’s not a 302 if it doesn’t leak oil.

[Arquemann]

A preliminary to-do list for this season, in some sort of an intended timeline:
- Figure out the lean running and do some tooonin' on the carb
- Put on the gorgeous reupholstered steering wheel (as expected, the brown plastic/vinyl wheel is getting sticky in warmer temps)
- Turbines! And new tires
- Inspection in June
- Dual exhaust

Wants list:
- Stereo / speaker upgrade (or atleast unplugging the overpowering dash speakers)
- 3G
- Sound deadening in the trunk and rear wheelwells

It’s not a 302 if it doesn’t leak oil.

Good thing my engine is like 2/3rds of a 5.0 HO

[jaywish]

maybe 225/65 is available?

[Arquemann]

Lean running issue seems to have been an easy fix, yet another split vacuum plug...
I should just remove the original vacuum tree thats at the back of intake now that I've got the new carb baseplate, it has a big vacuum nipple pointing at the back. Removing the vacuum tree would eliminate 3 vacuum plugs. Bits n bobs guy should be in town on friday, maybe I can get a 3/8" npt plug or whatever nominal size it is.

She idles very nicely now, kinda rich though. Very light throttle might be a bit lean for my taste, but 15.5-16 should be safe at low load and it runs smooth like that anyways. Mild acceleration without opening the power valve is also a bit lean, totally safe, but feels a bit sluggish and I'm definitely leaving horsepower on the table.
But I'll atleast let the weather warm up and drive it more before screwing with carb any more.

Also I put on the refurbed steering wheel, man it feels NICE!

maybe 225/65 is available?

225/65R15 is a rare size, atleast on this side of the pond. Kinda like finding left-handed lug nuts in metric.

[Kodachrome Wolf]

I've been trying to get new tires for the turbines, how can this possibly be so hard in the internet age...
I want to go with the stock 215/70r15 so the non-white walls wouldn't look ridiculously tall and to reduce the speedo error from the 225/70.

Silly question, but where is the inaccuracy most notable? Even when my '87 had P215/70R15 tires fitted, once it was past 55 MPH (retail 85 MPH speedometer head), accuracy started dropping like a rock. If I drove 80 MPH according to the speedometer, it was closer to 74 MPH. It currently has P225/70R15 tires and is 1 MPH fast (74 actual is reported as 75) across the entire speedometer, but it does have a 135 MPH police speedometer head fitted.

The LTD has the opposite issue, and the speedometer reports slower than actual above 45 MPH, and at 75 MPH displayed you're running closer to 79 MPH actual, and that's running on an appropriately converted alphanumeric to P-radial tire. Factory was a GR78-14, which works out to a P215/75R14 tire.

[gadget73]

If its a fixed percent off, its a ratio thing and tires or gear changes or whatever will affect that. If it changes with speed, its probably an issue within the speedo itself.

[Arquemann]

Kodachrome Wolf gadget73 it seems to be just a ratios thing. Under 50kmh its pretty spot on, it starts clearly differing from GPS numbers around 60-70, around 80kmh indicated actual speed is around 85-86. At 100kmh indicated the GPS speed usually jumps around between 105 and 107.

I certainly don't want to touch the speedo stuff, all the spinny bits are totally silent, the sweep is smooth and the needle doesn't bounce around at all. The most well-behaved mechanical speedo I've seen, could easily be fooled for it being electronic.

[jaywish]

It used to be the price of rotors and drums far outweighed the few bucks charged to resurface. Then non us stuff made it really cheap to change rotors and drums kinda faded out of general use. Now however I see the price of rotors exploding. Tariffs? Plus how many parts stores even have machine shops these days? Used to be all the parts stores around here did machine work. valve job to go with those spark plugs? All chains now out for max profits and volume.

[Arquemann]

It used to be the price of rotors and drums far outweighed the few bucks charged to resurface. Then non us stuff made it really cheap to change rotors and drums kinda faded out of general use. Now however I see the price of rotors exploding. Tariffs? Plus how many parts stores even have machine shops these days? Used to be all the parts stores around here did machine work. valve job to go with those spark plugs? All chains now out for max profits and volume.

Did your post get lost? I kinda feel this one doesn't belong here