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[Mustang5L5]

Ok. Did some Mustang stuff this AM when I was granted some free time.

The AC….still working nice and cold.

The cruise control. Does not work. I put the rear up on jackstands and took the car to 50mph and tried to activate it. Nothing. The tests I did with the rotunda tester showed all systems working, so not sure what’s up with that.

One bad guage cluster LeD. It flicks on and off. Highly annoying so looks like I’m pulling the cluster out (again)

Took some decibel readings. Too bad I didn’t do it before the sound deadening, but I think these are decent numbersZ


At idle, about 6’ behind the car : 86 decibels
At idle, interior : 70-75 decibels

Snapped the pic here at 70 but it was jumping from 70-75 so let’s call it 73 average. Windows up. Hvac off.



And of course, healthy 5k Rev was 106 decibels through the Bassani catted H-pipe and flows. Curious to see how these numbers change when I swap to the Borla Pro XS (which I have not purchased yet)


But now I have a baseline on record. I’m really happy how much quieter it is in the interior. It’s a noticeable difference at idle.

 

[Mustang5L5]

Of course here’s the DD at idle, which certainly doesn’t compare. But I still feel good at how quiet the inside is of the fox

 

[General karthief]

I've often wondered what the two dots at 20-60 mph is for, do you know?

 

[Mustang5L5]

I've often wondered what the two dots at 20-60 mph is for, do you know?

I think they are calibration marks. They would check the speedo against a calibrated input and if it was between the two dots when would call it good.

The 160mph has them too. 20mph, 60mph and 120mph

What’s interesting is the calibration dots have a wider allowable tolerance at 120mph on the original factory install gauge.

85mph has double marks. No idea how these were used

 

[Mustang5L5]

Ok looks like there is some variation in the 85mph speedo as well.

As the original speedometer my ‘88 was built with. E8 part number. You can see the differences from the 87 unit (guess, due to the E7 part number) above.

88-later has a pin stop, and single calibration marks and has a 0 and 10mph mark while early has 5 and 15mph.


The tick mark below 0mph is where you align the needle with the pin stop removed.

 

[Mustang5L5]

Drove it around the block. Doesn’t even feel like the same car! (Sound deadening plus subframes plus AC!! )

(Yeah I still gotta swap my coolant overflow)

Brakes still need to be bled. Stops fine but feels mushy.

I also think I’m gonna swap my old 180 tstat back in. This new Motorcraft 192 is too “digital” the temp goes up and down too much 200 to 190 back to 200 down to 190. My old 180 would “throttle” much better and just stay a constant 188 degrees. I like that number better.

 

[RekeHavoc]

I'm sure you didn't really get on it too much, but any initial comments on how the power feels? I'm considering a very similar combo for mine.

That coolant overflow needs some 12 pt ARP hardware.

 

[bird_dog0347]

Not only the subframes, but you also did the frame rails up front, and the K member... it's not the same car.

 

[Mustang5L5]

I'm sure you didn't really get on it too much, but any initial comments on how the power feels? I'm considering a very similar combo for mine.

That coolant overflow needs some 12 pt ARP hardware.

I didn’t get on it at all really. Didn’t really leave the neighborhood so lots of kids out in the street riding bikes and stuff. Kinda a little teaser blip but not enough to really draw any conclusion.

A few things to tweak and I’ll do a longer ride next.

I do need fresh gas. Very little 2.5 year old gas left in this thing. First time seeing the low fuel light on since adding the warning light module to my LX

 

[Mustang5L5]

Just dawned on me why the CC wasn’t working.

 

[General karthief]

Brake light bulbs?

 

[Mustang5L5]

I have LED brake light bulbs in. The CC measures resistance through the brake circuit to turn it off. The LEDs just don’t provide enoigh

 

[Mustang5L5]

So the solution is this…

SOLVED - Cruise Control and All LED brake light conversion - thanks Tore! - Rennlist - Porsche Discussion Forums

993 Forum - SOLVED - Cruise Control and All LED brake light conversion - thanks Tore! - A little over a year ago I converted the last of my brake lights, the CHMSL, to an LED strip. I took my my CHMSL strip and soldered a bunch of little LEDs to it....

rennlist.com

Or just stick the incandescent bulbs back in.


Hmm….seems like a winter project. I’ll put the bulbs back

 

[Mustang5L5]

Wanted to just verify the speedometer accuracy. I built a quick excel formula to calculate the speedometer cable RPM based on vehicle MPH




My drill has 2 speeds. I used a hand-held tach to determine the RPM of my drill at the low and high speed to give me two points to check. I set the speed up on my desk, hooked up my spare speedo cable to the head, and to the drill, and ran it at high.

At high speed on my drill, i should be reading 121MPH. I think i'm close enough


Cleaned up the speedo head and installed in a spare cluster I have. Need a new lens and I need to test all the other gauges. This one i'll save.

Just for grins, i calculated out that my low speed on my drill was around 35MPH. Pretty darn close

 

[Willybill32]

Wanted to just verify the speedometer accuracy. I built a quick excel formula to calculate the speedometer cable RPM based on vehicle MPH




My drill has 2 speeds. I used a hand-held tach to determine the RPM of my drill at the low and high speed to give me two points to check. I set the speed up on my desk, hooked up my spare speedo cable to the head, and to the drill, and ran it at high.

At high speed on my drill, i should be reading 121MPH. I think i'm close enough


Cleaned up the speedo head and installed in a spare cluster I have. Need a new lens and I need to test all the other gauges. This one i'll save.

Just for grins, i calculated out that my low speed on my drill was around 35MPH. Pretty darn close

I changed the stock 2.73 rear gears to 3.55 and added the best match for a new speedo gear at the trans, then used a GPS speedo app on my phone to see how accurate the speedo was. It’s about 3 mph slow at 60 mph.

Bill

 

[limp]

I changed the stock 2.73 rear gears to 3.55 and added the best match for a new speedo gear at the trans, then used a GPS speedo app on my phone to see how accurate the speedo was. It’s about 3 mph slow at 60 mph.

Bill

That is the best way to have your speedo.... When you are driving " just a little over" your just right......

 

[Mustang5L5]

That is the best way to check, but I had three different speedo in which I robbed parts from one to fix another. Just easier than slapping them all in a cluster and going for a drive. At least I can see if I’m in the ballpark

 

[Willybill32]

That is the best way to check, but I had three different speedo in which I robbed parts from one to fix another. Just easier than slapping them all in a cluster and going for a drive. At least I can see if I’m in the ballpark

@Mustang5L5, since you’ve been modifying/fixing speedos, maybe you can help me. I put a Ford Motorsport 140 mph speedo in my ‘86 when it had about 2,500 miles on it. It’s now got 98,000 on it, and the trip odometer turns erratically when it hits 100 miles. Is this something that can be repaired?

Bill

 

[Mustang5L5]

Would have to really take it apart to look at it.

I haven’t messed with the pre-87 units yet, but those trip odometers are easily swapped out. They have an E4 (1984) part number so I think you can just replace it.

You would just undo the two 1/4” bolts on the bottom and the whole trip odometer section comes out. Easy swap if you grab one off any other 84-93 speedo

I haven’t disassembled a trip odometer yet.

 

[Willybill32]

Would have to really take it apart to look at it.

I haven’t messed with the pre-87 units yet, but those trip odometers are easily swapped out. They have an E4 (1984) part number so I think you can just replace it.

You would just undo the two 1/4” bolts on the bottom and the whole trip odometer section comes out. Easy swap if you grab one off any other 84-93 speedo

I haven’t disassembled a trip odometer yet.

Thanks, Mike! Now to work up the gumption to pull that cluster one more time!

Bill