Today i aquired an 83 F250 4 speed that didn't come factory with a tach. Someone put an aftermarket on it, but i would like to know approximately where it redlines so i can set the little needle, it doesn't matter if its perfect i just want it there. I gues its kind of a pet peeve or somethin. Thanks.

 

I'd say 5000 is a good redline mark...purely an educated guess...

 

ok so your telln me my 88 351 can only turn 5 grand or so reliably? whats with the mustang guys theyr engins hit what 6500? how come mustang engines turn better than my truck is theyr intake setup that much better. i guess my question would be whats the difference betweenn the mustang designs ( they all r pretty much the same) and the trucks are so much different?

 

Not to start anything, and I am the one that asked the question so i don't know jack about a 351, but he did say it was an enducated guess. It may be able to turn a lot more, but thats all i wanted was an aproximation. If someone knows for sure thats great too.

 

I'd have to agree with mustang on this. 5000 for a stock motor with some mileage. You could probably go 5500 if you check the motor out.
For 4wheel- Same thing. An 88 motor is 17 years old with a truck cam. If it has been rebuilt with some good parts you could go to 6500.

 

351w is 5500rpm redline a 302 is mor like 6200.
the 302 is built differently and has light parts thats why it even revs quicker.

the 351w can be built to redline around 7500 but will not have a long life even with the proper hardware.

 

Thanks guys, I will probably just stick with 5 grand bein as high as i ever take it. Its a stock motor, no modifications, 132k on it. I will probably never get quite that high, but its nice to know what it can do safely.

 

My truck 302 went to 5500 rpm redline, the mustangs have a different cam/intake/exhaust w/ 6250 redline.

The redline is not always determined by whether or not the engine will come apart, but by how much air it can flow...the mustang 302 is the same bottom end but since it's top end can flow more air it gets a higher redline.

The 351 in my 89 goes to 5000, after 4500 it can't even really flow any more air so it just won't really climb in RPM. An engine with some miles on it is much more likely to come apart...and there really isn't any point to run it at max RPM since there is no power up there anyway...

 

isnt the 6250 the cutoff for fuel in a mustang? actual engine redline is lower, like 5800-5900 according to the tach.

 

huh well i didnt know that i just figured 5000 was where the cam ran out of oomph. I dont push my truck that hard ne more, the last one didnt like it to much. so now i baby this one

 

On an older 351w I would go no higher than 5000 rpm, as I knew a guy who took his to 5500 ONE time, and ended up with some collapsed lifters. Not worth it on an old motor. The truck cam set up was not designed for that much rpm, besides if it's stock, it probably runs out of breath at approx. 4500 rpm.

 

> whats with the mustang guys theyr engins hit what 6500

At least since the late 60s, many times a Ford truck will have a lower compression ratio engine along with less horse power (along with 2 bbl manifolds) compared to the same engine in a car.

5k redline is a good number for any V-8 (ford, chevy, dodge), especially one hitting 20 years old. On my older V-8 engines I try to keep it to 4k or so. Which is beyond the torque or power curve on many Ford V-8s anyways.

 

This thread makes me miss my old '92 E150.. 351w, would shift at 5200rpms when at WOT.. It was a pig off the line, but from a 20mph roll there wasn't a whole lot that could catch it. Sold it to the little bro with ~167k on it, he sold it when it hit ~200k, still going strong. We know the guy that bought it. He uses it every day for his painting business.

 

My old 69 Cougar with a 351W use to easily hit 7200 rpm with no valve float what so ever.

(dang) I miss that engine.

'78 Custom, if I were you, I wouldn't push it past 5500 rpm.

Me however, well that's a diffrerent story.

 

Honestly, 5k is a good shift point since the stock cam isn't worth beans beyond 4800k or so.