3.9 L Mirada CMX

4speedjim said:
Did you make a deal with Gator for his cmx? Sounded like a good car. I just couldn't afford it, and didn't want to insult him with what I could pay.
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No, at least not yet. I just don't have anywhere to put it, otherwise it would already be here. I tried to convince my brother that his barn needed another of my toys, but he didn't see things my way. I haven't given up yet, though!
 
LMAO AJ! Oh boy, ya I'm gonna need schooled. Was that in the newbie section? I sincerely apologize to all the trannys and DAKs in out humble site. The dresses looks nice on you guys, er girls er uh DAKs...? Trannys? BTW, Your nails look good. Go great with the Adams apple. heh heh heh... Flattery usually works AJ. I do need schooled. I'm not up on the new slang. Last I learned was cool and hot are the same thing, bad is good, all the rest is vulgar. I am bi-lingual in vulgarity. Its just the nature of the beast. I'm a hunt and peck one finger kind of guy too. And abbreviate more that I should. But, Ive been very good on my vulgarity. If that counts for anything?
 
In an Oregon CL ad, a turbo gasket and flange kit for a 170 SlantSix.
Hx35 and Slant 6 header flanges and t3 turbo flange 1/2

Amazing what you find when you type stuff in.

It might be as or more instructive to adapt the modern EFI and engine management equipment from that 3.9 to the Slant Six so that an appreciation for the simplicity of a carburetor can be developed. :)

I agree, great info from these guys.
 
Mr Volare Imperial said:
Those are some handy mathematics, thanks.
One point, tho, did I read 3.2L = 225CID? I think the 225 should be listed as 3.7L, and the 170 is 2.7L. I think the 194 slant 6 may have been at 3.2L, if that changes the #s.
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Someone should have caught mine... so a 194 /6 = a 198, of course, and the 170 is termed a 2.8L in Wiki, so I'll go with that...
 
So Ford's latest "Better Idea" is to split the output from the exhaust manifold thru one channel that is smaller than the other. The small channel hits the single turbo's vanes at a certain point, the larger channel with more mass but at a slower rate hits the pre-loaded turbo's vanes at a different angle.

The principle involved relates to how a smaller channel of air rushes thru at a faster speed than a larger channel. The effect is to help spool up the turbo for when the larger channel's air mass catches up and hits the other part of the turbine's vanes... as I understand it.

Picture a 170 /6 with a larger turbo at the engine, then splitting the exhaust into a 2'' pipe (hi-flow cherry bomb muffler) and a 2 1/4'' pipe (std muffler) running back to a rear turbo of smaller, faster spooling size which would employ the Ford design of applying different velocities to two different points on the turbo. Would that not drag the front turbo into action faster if your scavenging turbo in back has a head start?

A good write-up of one of the Chrysler engine engineers from the era...
Pete Hagenbuch - interview with a Chrysler engine development engineer (part 1)
Pete Hagenbuch has some good /6 upgrade info in the interview. He has a humorous take on the offset rod journaled V6s from Buick and the 3.9 mopar, too. Boom-boom, boom-boom. :)
 
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Mr Volare Imperial said:
So Ford's latest "Better Idea" is to split the output from the exhaust manifold thru one channel that is smaller than the other. The small channel hits the single turbo's vanes at a certain point, the larger channel with more mass but at a slower rate hits the pre-loaded turbo's vanes at a different angle.

The principle involved relates to how a smaller channel of air rushes thru at a faster speed than a larger channel. The effect is to help spool up the turbo for when the larger channel's air mass catches up and hits the other part of the turbine's vanes... as I understand it.

Picture a 170 /6 with a larger turbo at the engine, then splitting the exhaust into a 2'' pipe (hi-flow cherry bomb muffler) and a 2 1/4'' pipe (std muffler) running back to a rear turbo of smaller, faster spooling size which would employ the Ford design of applying different velocities to two different points on the turbo. Would that not drag the front turbo into action faster if your scavenging turbo in back has a head start?

A good write-up of one of the Chrysler engine engineers from the era...
Pete Hagenbuch - interview with a Chrysler engine development engineer (part 1)
Pete Hagenbuch has some good /6 upgrade info in the interview. He has a humorous take on the offset rod journaled V6s from Buick and the 3.9 mopar, too. Boom-boom, boom-boom. :)
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Very interesting. For this low cost project, I'm going to stick with the 3.9, in mostly stock form, with whatever bolt ons I can find. That being said, I now have a 170 and a 225 to experiment with. Maybe next year's project will be a boosted slant.
 
Just keep in mind, it's a labor of love.
You'll be pouring dollars in,and getting change worths out, and all the while, you'll have to listen to that stinking BOV. What I mean is; even if you double the power of those slantys how much power is that? Less than a stock 5.2Magnum for the 170, and maybe as much as a stock 5.9Magnum for the 225?
But I guess you could be brave and turn the boost up to triple the power, and then you'd have something. At least for a little while.
Hyup, a labor of love.
Well, that, and the sound of a screaming 170 is pretty different........And Ima thinking you could squeeze some pretty good mpgs out of a slant, relative to it's output.........and they are pretty smooth, as far as that goes........ and they say a boosted 225 is pretty torquey.....and............for sure it would be different. Kindof like the CMX itself. ............................................................BTW,what's one of those weigh?........................oh.......ow
 
AJ/FormS said:
Just keep in mind, it's a labor of love.
You'll be pouring dollars in,and getting change worths out, and all the while, you'll have to listen to that stinking BOV. What I mean is; even if you double the power of those slantys how much power is that? Less than a stock 5.2Magnum for the 170, and maybe as much as a stock 5.9Magnum for the 225?
But I guess you could be brave and turn the boost up to triple the power, and then you'd have something. At least for a little while.
Hyup, a labor of love.
Well, that, and the sound of a screaming 170 is pretty different........And Ima thinking you could squeeze some pretty good mpgs out of a slant, relative to it's output.........and they are pretty smooth, as far as that goes........ and they say a boosted 225 is pretty torquey.....and............for sure it would be different. Kindof like the CMX itself. ............................................................BTW,what's one of those weigh?........................oh.......ow
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Yes, yes. A labor of love is right. That's why we do the things we do! Anyone could build a killer small block, just like every other killer small block. A killer slant would be kind of special. That's the kind of build I like. Kind of like a 3.9L CMX, too!
 
You go Joe, I'll be rooting for ya!
But I want to see staged turbos on the 3.9. A Big and a Llittle. And I want to see the little one right down by the passenger footwell, slamming fresh air into the bear-keg, creating the exhaust heat to drive the remote one mounted under the rear passenger seat. Yeah that will take some creative valving. And no mufflers;just a T/A dump in front of the rear tires.Instant throttle response and locomotive-like torque to power that 2-ton behemoth right into next Thor's-day. Common Joe, I've been waiting all my life for someone to do that to a 273, but I'd be happy with seeing it done to a 3.9
And you know what else I wanna see Joe? I wanna see another stick in the cab. Not a shift stick. But a boost control stick. Not a knob, but rather a stick. Hang it from the ceiling and juxtapose a gauge on it that reads something like "grandma,dad,Little Johnny, and Flash-Gordon", as the stick travels from minimum boost to blow-it-up boost.You might want to provide locks at various levels until Little Johnny gets the hang of it,lol. I mean boost can make that 3.9 into 300hp, Or 400hp, Or do-you-dare 500hp.Well maybe not 500,eh?
Ok but that would be my dream. I'm 64 now and still waiting. Maybe in my next life..... oh wait, I might have wings in the next life, and be able to travel at thought-speed. I mean why else is New Jerusalem described as 1400 miles by 1400 miles and JUST AS HIGH. I mean to get to the top would require quite the elevator. Ima thinking we get power of flight. or at least levitation,lol.
Go Joe.

Oh wait, we were talking slanty power.
Ok then, but now little twins; one off the front three, and one off the back three. Pow! hit her early, and hit her hard! But that dang BOV is gonna drive you nuts . It might be best to keep it an automatic,lol.
Go Joe, time is running out! ....kids are only kids for a short time, and then they slip away.....
 
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I've thought about doing a turbo 3.9 V6 in a Mirada for years. It would be like a Mopar version of the Buick T types. I have an '80 CMX in my garage and the 3.9 from a '95 Dakota sitting on the floor next to it. To be honest, that may be all the further it gets, but it's nice to dream about.
 
Why use the 3.9L and not a 318/360 LA or Magnum as the basis of a twin turbo, aside from the unique aspects of a 3.9L V6? A lot more low end torque to start with, and you wouldn't need as much fabricating or need to run as much boost.
 
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Steve2961 said:
I've thought about doing a turbo 3.9 V6 in a Mirada for years. It would be like a Mopar version of the Buick T types. I have an '80 CMX in my garage and the 3.9 from a '95 Dakota sitting on the floor next to it. To be honest, that may be all the further it gets, but it's nice to dream about.
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That's exactly what I was thinking! For now I'm going to install the stock 3.9 drivetrain, while I save a little cash and do a little research on the turbo setup. Or should I say, I'll make my son save up a little cash!
 
kkritsilas said:
Why use the 3.9L and not a 31/360 LA or Magnum as the basis of a twin turbo, aside from the unique aspects of a 3.9L V6? A lot more low end torque to start with, and you wouldn't need as much fabricating or need to run as much boost.
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The original plan didn't really include turbos, or any other real modifications, just a later model stock OBD II drivetrain swap. I got a good deal on the 3.9 2wd Dakota, so that's what I went with. If I found a 318 or 360 drivetrain first, that's what I would have ended up with. I do like the fact that the 3.9 will be unique in a Mirada. The turbo idea was just to add a little power, and be even more unique. The car is my 17 year old son's, so I'm not really looking to make a ton of power.
 
I understand the unique aspect, and the use of modern drivetrain components (great working fuel injection and multi-speed gearboxes). However, finding a decent LA or Magnum would still be pretty cheap, and won’t require all the effort to install. Add a third party fuel injection system, and you’re good to go, and a lot fewer issues with heat (compared to a 3.9L/turbo set up). Power won’t be too high, and later on add a turbo or supercharger if needed. Maintenance will be easy, and cheaper, than the 3.9L, even without a turbo.
 
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And MagnumV8 torque will make a believer outta you.
3.9 torque can't hold a candle to a V8 . Well, I shouldn't say that, go back to post #2, 190ftlbs@1200 is no slouch. Take another look at this
power-39-gif.gif

If you extrapolate the torque line out to 5600, you will see the power there has only dropped to 170est. x 5600/5250=181. So what does that mean?
Well for starters that whoever created the graph shoulda done us a favor and buzzed the engine up to maybe 6400. And second that the power seems to be ruler flat from 4800 to 5600,at the least! Thasa whole lottaflat! and thirdly that this little funky-crank engine likes to rev. So don't be afraid to put some performance gears in the back.What it might lack in V8 torque, it makes up for at the other end.And fourthly, she wants headers.
I see a 6400 rpm 1-2 shift rpm to drop in at 3600 with that A500 or any of the Mopar wide-ratio transmissions.and
I see 4.88s in the back, to hit 60 mph @ 5600 at the top of second gear.and
I see 65=2780 in od. Yeah that would scare some V8s all rightee.

In any case; in the uniqueness department,I'm still rooting for you Joe!
 
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kkritsilas said:
I understand the unique aspect, and the use of modern drivetrain components (great working fuel injection and multi-speed gearboxes). However, finding a decent LA or Magnum would still be pretty cheap, and won’t require all the effort to install. Add a third party fuel injection system, and you’re good to go, and a lot fewer issues with heat (compared to a 3.9L/turbo set up). Power won’t be too high, and later on add a turbo or supercharger if needed. Maintenance will be easy, and cheaper, than the 3.9L, even without a turbo.
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I know the 318/360 would have been a stronger starting point, but I already got the 3.9 complete truck for next to nothing. Besides, I’m pretty sure it will be the only one when it’s done, whether or not it stays stock.
 
kkritsilas said:
Wikipedia says it is the 6 cyldiner version of the 318, and there were 3.9L LAs and 3.9L Magnums.
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I believe the 98 3.9L is a Magnum. I might even be able to use slant six to V8 conversion mounts to save some fab work, if the 3.9 has the same mounting points. I’ll know more this weekend.
 
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