How much hp can the ford 7.5 handle?


ericbphoto

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7.5/28 spline 8.8 1.21"

31 spline 8.8 is 1.34"

8" from what I can see uses 1.1875" shafts from the factory.

IMO the diff is the weak point of the 7.5 moreso than the shafts.
Don was talking about pinion diameter. Not axle shaft diameter.
 


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7.5/28 spline 8.8 1.21"

31 spline 8.8 is 1.34"

8" from what I can see uses 1.1875" shafts from the factory.

IMO the diff is the weak point of the 7.5 moreso than the shafts.
Input pinion on 8" is 25 spline and 0.993" diameter.

Axles are 45° pressure angle for 8 and 9", so slightly larger than the 30°pressure angle found in 7.5 and 8.8" so you can't swap even if spline is the same.
 

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I think these days simply finding an 8" axle is going to be hard. When did they quit building those, mid-late 70's? That narrowed 9" is looking pretty good from over here but I think you'd be surprised at what the 7.5 will hold up to. Main things I have seen go bad on them are the spider gears and center pin (holes in the carrier get egged out.) Occasional bad pinion bearings and wheel bearings but it's all just wear and age related stuff. I've actually seen far more junk 8.8s than I have 7.5s.

I know more than a couple guys who have destroyed quite a few sets of gears in D6/7/80s, 14 bolts, Sterlings, big stuff... anything can be broken.
 

rusty ol ranger

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I know more than a couple guys who have destroyed quite a few sets of gears in D6/7/80s, 14 bolts, Sterlings, big stuff... anything can be broken.
I know anything can be broke but...

What in the hell do you have to do to break a D frickin 80?
 

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The 8" was last used in 1980. It wasn't hard to find one, I just went down to my basement and grabbed the housing along with everything I needed to build one except a bearing kit. My mustang 8" has an Auburn Pro in it and survived 20+ years of drag racing in a stick shift car. I'm not worried about an 8 holding up behind a mild 351 in a 2wd truck with stock type tires. 8's and 9's are a lot nicer to work on and this truck's purpose is to make me happy.
 

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I think itll be ok for a bit. Tires will play the biggest role. Espicially with a light ass ranger rear end.
Yeah, light-ass is the thing. Remember that Ranger Ford built? The one they put a Lightning motor and drivetrain in it? Biggest problem they had with that truck, even with 12 inch rims and 335/35 tires, is they couldn't launch it. They didn't build it because they thought it was beyond the average person to b e able to handle it.

It was called the Lightning Bolt. Below are some pics. Don't you just wish they had built this beastie? I'd have one for certain. Back tire life would likely be costly though. LMAO!!

https://www.google.com/search?q=Ford+Lightning+Bolt&sxsrf=ACYBGNTBoj6F9gRaCpjDqOqeZkBEoSz8Xw:1575945747282&tbm=isch&source=iu&ictx=1&fir=Uk5yJB1nckpORM%3A%2COXVsQKMorhlZBM%2C_&vet=1&usg=AI4_-kS8_27r7WDrASqtwPTfXGPquwPgcw&sa=X&ved=2ahUKEwjkyM6zh6rmAhVITd8KHcZ3AO0Q_h0wFXoECAwQBA&cshid=1575945999546362&biw=1440&bih=781#imgrc=Uk5yJB1nckpORM:
 

alwaysFlOoReD

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Yeah, light-ass is the thing. Remember that Ranger Ford built? The one they put a Lightning motor and drivetrain in it? Biggest problem they had with that truck, even with 12 inch rims and 335/35 tires, is they couldn't launch it. They didn't build it because they thought it was beyond the average person to b e able to handle it.

It was called the Lightning Bolt. Below are some pics. Don't you just wish they had built this beastie? I'd have one for certain. Back tire life would likely be costly though. LMAO!!

https://www.google.com/search?q=Ford+Lightning+Bolt&sxsrf=ACYBGNTBoj6F9gRaCpjDqOqeZkBEoSz8Xw:1575945747282&tbm=isch&source=iu&ictx=1&fir=Uk5yJB1nckpORM%3A%2COXVsQKMorhlZBM%2C_&vet=1&usg=AI4_-kS8_27r7WDrASqtwPTfXGPquwPgcw&sa=X&ved=2ahUKEwjkyM6zh6rmAhVITd8KHcZ3AO0Q_h0wFXoECAwQBA&cshid=1575945999546362&biw=1440&bih=781#imgrc=Uk5yJB1nckpORM:
Link no good.
 

alwaysFlOoReD

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You must have cleaned up your link, its working now.
Thanks.
 

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You must have cleaned up your link, its working now.
Thanks.
Didn't do a thing to it. I bet what happened is the first time I posted it, the link didn't work. I cleaned it up PDQ. Meanwhile, judging from the time I posted and you replied, you probably caught it before I got it fixed. Winner of the bad timing award for the night.

Anyway, it sure is a bad ass ride. I wish Ford had made that one. Only one error in that write up. They said 9.25 rear end. The lightning has a 9.75 limited slip differential. I would know. ;-)
 

alwaysFlOoReD

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I was surprised that it only did 13.5 and 108. Must not get traction.
 

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I was surprised that it only did 13.5 and 108. Must not get traction.
Yeah, I have an old 2003 Hot Rod magazine that had a short write up on it. And that is one of the things they said about it, impossible to get a good launch without insane wheel spin. Even with those massive 345/35 rear tires. That's just one of the Rangers traits. Too light on the rear wheels. I mean, I have a lightly modified 3.0 auto, and I can spin two Cooper Cobra GTs in 255/60-15 with the thread mentioned 7.5 rear end.
 


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