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Alright idk if I'm going to get flammed for this but I dont know how many RPM my 1991 bronco should be running at on the highway. My brother and I just put a new roller 302 in it a couple of months ago. It has 33x12.5x15 on and I believe stock 3.55 gears. The spedo has not been corrected and the transmission is the E40D. This is my first automatic and want to make sure it is performing close to what it should be doing. Im also asking this because im driving 90 miles to Houston tomorrow after work.

Sorry but I dont know anything different than my Mustang and 5spd but im tryin to learn.

Also the cooler and filter are on the way in the next few weeks

Could you guys give me a rough idea on the rpm's I should have doing 55, 60, and 65.

Thanks
Mike
 

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I would say that if you are over 3 grand it is a cause for concern. 2700 medium range for concern, If you have a 2300 RPM for 65 you are doing better than all right. I would not worry unless I was hitting the upper 2 g'es at 65 or the low to mid 3,000's at the max MP. (with the E4od)
 

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Addicted to Junk
85 Bronco, 309ci I6 w/4bbl, np435, 4" lift, 37" Irok NDs, 4.56 w/ Detroit Locker and tru trac
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with 35's and a 5.8/e4od, i was turning about 2100 at 70, so i would assume you would be turning 2300 or so
 

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Kitteh Commandaar!
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No comment Whammer as I don't have a e4od tranny.

Second thing is, if anyone here has a 5.0 C6 combo(3.55s), could you comment as well what I should be running around 55. Tach reads around 2800 or so, I know it doesn't have a overdrive, so I just wondering.

Sorry, not trying to hijack Whammer. :thumbup :beer

KC
 

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I would say that if you are over 3 grand it is a cause for concern. 2700 medium range for concern, If you have a 2300 RPM for 65 you are doing better than all right. I would not worry unless I was hitting the upper 2 g'es at 65 or the low to mid 3,000's at the max MP. (with the E4od)
no.


With 33's, 3.55's, and an OD ratio of .71(IIRC) on an E4OD, at 2000 rpm, you should be at almost 80mph.

Any less then that, and you're either not in OD, or your transmission is slipping. E4OD's lock up, so you don't have loss through the torque converter. If it doesn't lock up, you generate a ton of heat, and you'll probably burn up your transmission.
 

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I have a 302 with a C-6 and 33 x 12.5 tires. At 55mph I run around 2300-2400 RPM. I am adjusting for the speedo calibration. At 65 MPH I am running around 2600-2700 RPM.
 

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Kitteh Commandaar!
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I have a 302 with a C-6 and 33 x 12.5 tires. At 55mph I run around 2300-2400 RPM. I am adjusting for the speedo calibration. At 65 MPH I am running around 2600-2700 RPM.
Ok, so its not suprising that its running a little high. I have 235s (about 29"ers so I have read) so I guess the motor is just compensating for the smaller tires compared to you. Thanks for the reply angeladave2002! :thumbup

KC
 
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