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Discussion Starter #1
Okay, I've been crunching numbers and I'm still at a loss...
This all pertains to the '89 351W with a C-6 (rebuilt 15k and 3 years ago).

-Which is a 3-speed with top gear being 1:1 ratio, yes?
-With 32x11.5's
-with an axle code of H9, which is a 3.55 limited slip

With that, I should be doing @ 2200rpm at 60mph

Now, I don't have a tach, but there's no way I'm doing that. It's more like 3500-4000rpm. My shifts occur at 25mph for 2nd and 35mph for 3rd.

Wiskey Tango Foxtrot?
Is something slipping? Did the tranny place hose something up when they put in a rebuilt?
 

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Sound's like something isn't right,there's no way you should be spinning that much rpm with 3.55 gear's 32" tire's.I have 4.56 gear's and 35's and I'm not spinning that much rpm.
 

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Sounds like the problem I have, at present mine is all stock, just bought it, 85 351W, C6, and I run about 3000 rpm at 70 mph, with factory 3.50 ratio. Does this sound normal?
 

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Discussion Starter #6
"Sounds like you're stuck in 2nd maybe?"
That's what I thought when my wife told me about it. (The '89 is her Bronco)
No such luck. It's a firm shift, with noticable RPM change...only it's at 35mph.
Night and day compared to the 5.0L and E4OD in the '94.
 

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Im guessing thats normal. My bronco, with an AOD does around 2000rpm at 60mph. IIRC the overdrive gear on the AOD is .67:1. With a bit of math your rpm's should be at 3340
 

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i have the same setup as you 351w c6 and 3.50 gears with 32's and run around 3k if not higher at 70 if i remember right!
 

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How accurate is your tach as I need to find out how accurate mine is. I run a 351 with ac6 355 gears and 35 tires and when I do 60mph my tach says 2800 and I know Iam in 3rd as I have a shift kit the trans is only aprox 2 years old.
 

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Discussion Starter #11
It's a Custom trim level, so no stock tach. Just going by ears and feel. Not in the mood to install an aftermarket just so I can see my 351W spinning like a hamster on crank. It'll probably never have to go over 45 when we move to Maine anyways.
 
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