80 Mirada 318 tweaks

[MiradaMegacab]

If you got beer and a MigWelder you can fab up your own exhaust using 180* pre bent U Bends..... Pic is “up over the axle” tail pipe.

 

[MiradaCMX80]

View attachment 40355
If you got beer and a MigWelder you can fab up your own exhaust using 180* pre bent U Bends..... Pic is “up over the axle” tail pipe.

Well, I don't drink, and I don't have a welder LOL I got a quote from PF&E and they're excited to work on this for me. 2.25 inch to the back with Super Turbos and B-body style turn downs.

 

[Duke5A]

Well, I don't drink, and I don't have a welder LOL I got a quote from PF&E and they're excited to work on this for me. 2.25 inch to the back with Super Turbos and B-body style turn downs.

You'll like Gary, him and his crew do good work. They're the shop that fabricated my stainless headers. To give you an idea of the workmanship difference between them and Doug's: I had Doug's do a dual system for me and while they did a good job bending the pipe, it was hung with sheet metal screws through the rear floor boards. I was pissed. They even fell out. PF&E actually welded studs to the seatbelt support brackets under the rear seat to secure it.

You get what you pay for.

 

[BudW]

Is there any way to tell which alt is in it? Parts guy asked me if it was 100 amp. I have no clue.

The 100 amp alternator is huge (and heavy) and is reserved for cars with a lot of an electrical load (like police cars or cars with power everything).

The other 99% of us got the more normal alternator (not the 100 amp one)

The drive belts and pretty much all of the front engine brackets are different with the 100 amp alternator.
BudW

 

[MiradaCMX80]

You'll like Gary, him and his crew do good work. They're the shop that fabricated my stainless headers. To give you an idea of the workmanship difference between them and Doug's: I had Doug's do a dual system for me and while they did a good job bending the pipe, it was hung with sheet metal screws through the rear floor boards. I was pissed. They even fell out. PF&E actually welded studs to the seatbelt support brackets under the rear seat to secure it.

You get what you pay for.

I'm very excited about going there. I'm picky about how I want the exhaust to look and sound, and Gary sounded eager to work on it. The price may be a tad high for supplying my own mufflers, but as you said...you get what you pay for.

 

[MiradaCMX80]

The 100 amp alternator is huge (and heavy) and is reserved for cars with a lot of an electrical load (like police cars or cars with power everything).
View attachment 40356
View attachment 40357

The other 99% of us got the more normal alternator (not the 100 amp one)
View attachment 40358
The drive belts and pretty much all of the front engine brackets are different with the 100 amp alternator.
BudW

Thanks, BudW. While removing my a/c compressor and finishing the new alt belt routing, I discovered my alt is the original 65 amp, dated 1979.

 

[SRTMirada]

I had a 1980 Mirada CMX with a slant six and an 8 1/4 axle with 2.76 gears. I doubt that anyone swapped it in there. All Canadian cars came with the 100 amp alternator because of the rear window defroster.
I had another Mirada with a 318. I put in an 8 3/4 with 3.23 gears and a non lockup slant six converter. That combination ran great with the low 2.74 first gear ratio.

 

[kkritsilas]

My 1981 CMX has the 100A alternaor and an 8 1/4". Its a 318-4V/BBL car. My 1980 Cordoba has the same.

 

[jasperjacko]

This should be perfect with two 850 double pumpers. It'll run just like a Hell-cat!

 

[MiradaCMX80]

I had a 1980 Mirada CMX with a slant six and an 8 1/4 axle with 2.76 gears. I doubt that anyone swapped it in there. All Canadian cars came with the 100 amp alternator because of the rear window defroster.
I had another Mirada with a 318. I put in an 8 3/4 with 3.23 gears and a non lockup slant six converter. That combination ran great with the low 2.74 first gear ratio.

All of the Mirada trannies are the 2.74 first gear, correct? How did you get a non-lockup converter into a lockup 904? I had a feeling the 3.21/3.23 gear would be the better choice.

 

[MiradaCMX80]

View attachment 40373This should be perfect with two 850 double pumpers. It'll run just like a Hell-cat!

I'm sure it would be very reliable, too LOL!

 

[SRTMirada]

Yes, all Miradas came with the 999 transmission (or 727) that included the low 2.74 first gear, five clutch front drum, and 4 planet gears. I picked up an early '70's slant six 904 which are cheap and plentiful (or at least they used to be). Then I swapped the converter, input shaft, pump, reaction shaft and valve body into the 999. The pump needs to be clearanced for the 5 clutch drum and the reaction shaft needs to be opened up. It's a little bit of lathe work but not difficult.

 

[MiradaCMX80]

Yes, all Miradas came with the 999 transmission (or 727) that included the low 2.74 first gear, five clutch front drum, and 4 planet gears. I picked up an early '70's slant six 904 which are cheap and plentiful (or at least they used to be). Then I swapped the converter, input shaft, pump, reaction shaft and valve body into the 999. The pump needs to be clearanced for the 5 clutch drum and the reaction shaft needs to be opened up. It's a little bit of lathe work but not difficult.

I thought they came with the 904. If it was a 999 I'd be happy now that I know what they are. Either way...the guy who built the 727 for my friends General Lee only builds Mopar transmissions. He will be doing my trans when the time comes and knows all of the tricks. I don't plan on building a 450hp screamer, so I think a well built non-lockup 904 will do the trick with a 3.21 gear. Per the advice of another member, the gear will be the first major step this fall/winter.

 

[SRTMirada]

It's a terminology thing. Some people refer to every member of the 904,998 and 999 family as a 904. Your car should already have a 999. Tell your transmission guy that you want it converted to non-lockup. There are different ways to do that. I outlined what I think is the easiest and cheapest way. You'll be very happy with the results for a mild 318.

 

[MiradaCMX80]

It's a terminology thing. Some people refer to every member of the 904,998 and 999 family as a 904. Your car should already have a 999. Tell your transmission guy that you want it converted to non-lockup. There are different ways to do that. I outlined what I think is the easiest and cheapest way. You'll be very happy with the results for a mild 318.

Thanks for the info. My buddy was just here and we jacked the car up to inspect my gas tank wiring. (Broken wire.) If we counted right, the stock axle is only a 2.4 :/ Makes me more confident about a 3.21, but if I recall, that means I need a different carrier. He will be checking his "stash o parts."

 

[SRTMirada]

The 2.4 ratio sounds correct. Why not upgrade to a locking differential?
Auburn Gear High Perf Series Differential

 

[MiradaCMX80]

The 2.4 ratio sounds correct. Why not upgrade to a locking differential?
Auburn Gear High Perf Series Differential

Yes. If I stick with the stock axle, that's a given. LSD with a 3.21 gearset. Since my friend who was here with me is a B-Body owner, he is also looking for an 8 3/4 axle. We will compare the prices to do both. He's one of those people who always knows where the good deals are, and knows it'll fit into the car with little fuss. The factory ratios are confusing...I swear to goodness I saw that the 318 cars were 2.7, and 2.9 with A/C. Oh well.

 

[jasperjacko]

Your car should have a 2.21.

 

[80mirada]

mine was a 2.4, most 1980, 318 Miradas will have a 2.4

 

[jasperjacko]

interesting. I've had 6 j's, all had 2.21. 3-80', 1-81', 2-83'.