Don't know if this is a racing post or not, but...

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TrailBeast

TrailBeast

AKA Mopars4us on Youtube
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So the trans shifts into converter lockup at 65mph with 1,200 RPM, and my cam design power range is 3,500-6,000 RPM.
Anybody want to come with me and see what it takes to get into the cam in lockup OD?

Just kidding, as I can't afford the tires to feel comfortable trying to even get close to it anyway.
 
TrailBeast said:
So the trans shifts into converter lockup at 65mph with 1,200 RPM, and my cam design power range is 3,500-6,000 RPM.
Anybody want to come with me and see what it takes to get into the cam in lockup OD?

Just kidding, as I can't afford the tires to feel comfortable trying to even get close to it anyway.
Click to expand...


Sounds like you are geared wrong.
 
We figured it out mathematically some years back in a friend's Scamp: 360, A833OD, 2.76 rear, based on the indicated rpm on the tach. It was over 160mph. Not that I'd test it with todays imported tires, but back then (the 80s) the speed rating on the tires was not nearly as cricital...lol. He worked at a tire shop and what was on our cars was whatever take-offs had more tread than what was on the cars...lol. I know my Newport would go past 150, especially on the plate. That was verified by a CT State Trooper's radar.
 
jbc426 said:
Sounds like you are geared wrong.
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I'm inclined to agree. The engine is at peak efficiency at peak torque, so try to gear it so that your preferred cruising speed is at peak torque.

Addressing the original question, I agrees. Salt flats. I bet an honest 140 is reasonable in street trim
 
Reminds me of the night I was rowing through the gears just about to hit OD in the 75 Dart when it had the 2.45 gears..... and marginal tires at best....
 
jos51700 said:
I'm inclined to agree. The engine is at peak efficiency at peak torque, so try to gear it so that your preferred cruising speed is at peak torque.

Addressing the original question, I agrees. Salt flats. I bet an honest 140 is reasonable in street trim
Click to expand...

Geared wrong for what, the track? :D
If I wanted to be geared for peak torque I might as well have not done anything to it and left a 3 speed in it.
I can over ride either OD, lockup or both manually, so if I wanted I could still run down the freeway in 3rd only, 3rd with lockup, OD only, or OD with lockup.
I have choices.
This trans has the low first gear planetary set in it, and shift's 1-2 right after my back tires are over the crosswalk lines under normal driving, but I can still make a smoke cloud for a block in second if I want.

The normal freeway speeds in AZ are 65-75 but on a 75 everyone does 85-90 average (some 90-100)
The car did 120 before I did the Magnum and OD trans and now has more than twice the power and 2 extra gears. :D
140 shouldn't be a problem at all.
 
ScampMike said:
oh - you can say THAT again... hell, he put a Ford scoop on a Mopar! :lol:
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Hey, at least it was a Mach I scoop and not some machine screw drawer with the end cut out upside down on my hood. :D

Obviously it's overgeared and I forgot to mention that'll change a bit when the Grand Cherokee 8.25 with disc brakes goes in.
I am looking forward to getting that in there this fall (I hope)

MoChevForJeep Dart :D
 
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TrailBeast said:
Hey, at least it was a Mach I scoop and not some machine screw drawer with the end cut out upside down on my hood. :D
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LOL - oh OH OOHH - I am near speechless - so did moving the bumper in make it more aerodynamic/faster? or was that another attempt at making your Fo-par cooler? :rolleyes:
 
ScampMike said:
LOL - oh OH OOHH - I am near speechless - so did moving the bumper in make it more aerodynamic/faster? or was that another attempt at making your Fo-par cooler? :rolleyes:
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I can see you are having a lot of fun with this. LOL
It just brought the lines in closer under the grill, and where the bumper wraps around into the fender indents.
I didn't like the gaps the factory mounts left here and there.
 
what the... no jabbing retort!! - I see - so it was to make it more aesthetically pleasing.. ie; cooler. -- yea, the 73 and up Darts (Beak cars) are tough to look at... :lol: - I can see why you might do that...
 
TrailBeast said:
Geared wrong for what, the track? :D
If I wanted to be geared for peak torque I might as well have not done anything to it and left a 3 speed in it.
I can over ride either OD, lockup or both manually, so if I wanted I could still run down the freeway in 3rd only, 3rd with lockup, OD only, or OD with lockup.
I have choices.
This trans has the low first gear planetary set in it, and shift's 1-2 right after my back tires are over the crosswalk lines under normal driving, but I can still make a smoke cloud for a block in second if I want.

The normal freeway speeds in AZ are 65-75 but on a 75 everyone does 85-90 average (some 90-100)
The car did 120 before I did the Magnum and OD trans and now has more than twice the power and 2 extra gears. :D
140 shouldn't be a problem at all.
Click to expand...

I want the setup you have.
And for you to have a better one.
 
ScampMike said:
what the... no jabbing retort!! - I see - so it was to make it more aesthetically pleasing.. ie; cooler. -- yea, the 73 and up Darts (Beak cars) are tough to look at... :lol: - I can see why you might do that...
Click to expand...

They grow on ya, kinda like a wart on your nose. :D
 
jos51700 said:
I want the setup you have.
And for you to have a better one.
Click to expand...

The trans wasn't that big of a deal at all and I got forced into doing it at the same time the new motor went in.
Once I found that the hard parts to fix my 904 and rebuild it was almost exactly the same cost as buying a used 1995 42RH OD and a shift kit I didn't hesitate much. :D
Once the 8.25 Cherokee rear end goes in that will bring the gearing down some, but holy crap this thing is fun to drive.
As a matter of fact I have a service call I have to go on, so I have to go drive it again right now.

Later
 
Lots of things affect the cam's power range too. Intake style, exhaust, ignition timing. All that plays a role as well.
 
RustyRatRod said:
Lots of things affect the cam's power range too. Intake style, exhaust, ignition timing. All that plays a role as well.
Click to expand...

Exactly, and if I was going for all the power I could get out of it the intake and carb would be the first things to go.
The deal is though, that it runs great and is super reliable at about 350hp and the added 50 or so I could get out of it with an intake and carb change isn't worth it (to me)
Maybe down the road some day when I'm bored and want to waste a few hundred bucks on something I don't need anyway. :D
 
TrailBeast said:
Exactly, and if I was going for all the power I could get out of it the intake and carb would be the first things to go.
The deal is though, that it runs great and is super reliable at about 350hp and the added 50 or so I could get out of it with an intake and carb change isn't worth it (to me)
Maybe down the road some day when I'm bored and want to waste a few hundred bucks on something I don't need anyway. :D
Click to expand...

Your build is what I'm after. Midrange happy funtime.
 
AJ/FormS said:
I want to say something but nothing's coming to me.

Ou-Ou here it comes. 1200@65 in lock up with .69 OD and say 26" tires is 2.08 rear gear!
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Ok.
Sorry AJ but I don't know what your point is there.
They don't make that gear or something like that?
 
I don't know.
I didn't see what gears you are running back there, and was too lazy to hunt it up,lol
If you have 2.08s then the math is right.
If you don't, my memory could be wrong on the 42 o/d ratio
But if my numbers are right and you have 2.45s say, the math spits out 1421 in lock-up, with 26s,
 
AJ/FormS said:
I don't know.
I didn't see what gears you are running back there, and was too lazy to hunt it up,lol
If you have 2.08s then the math is right.
If you don't, my memory could be wrong on the 42 o/d ratio
But if my numbers are right and you have 2.45s say, the math spits out 1421 in lock-up, with 26s,
Click to expand...

I honestly never cared enough to even check it, but I know 80mph is approx. 1,800 RPM's and I think you have the OD ratio and tire size right.
I'll check the tires right now just for kicks and edit this with the size.

Just a hair over 26" (maybe 26.25)
 
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