TOP SPEED

[jandncope]

I have a 77 GMC, 10 windows long, 366 gas, allison auto. I only get 55mph before the "engine overspeed" light comes on. Not sure on the actual RPMs as I dont have a tach. I tuned it up and have great acceleration, and plenty of petal left at 55. Anyone drive theirs any faster?

[smitty500]

91 blue bird with a 366. 75 mph on my guage and with my buddy following me. I still have some more reserved.

[opus]

This maybe too early a model but check the fuse box. We used to pop a fuse for the govenor when we transported Ryder trucks back when. Worked for the 366 and Ford 370. Wow, those were the days!

[bapos]

I have a 1983 GMC Ward and it also has this engine over speed light that came on when traveling down the highway. I looked at the tach and we were will in the upper range of it (3600 or so) and it came on. On other various speeds which were higher than the one before it didnt come on? So not sure what it is based on cause I ran more revs and it didnt come on.... and ive ran more rpms and it didnt come on?

My wife did come on the bus so there is a possibility of some of her devil powers being transferred to it? Hopefully they are in the good way?

if someone knows or has a clue on this let me know.


Bapos

[Redbear]

Hmmmm . . . . Methinks it is more of an employee management tool than an engine management tool.

I suspected it in the original post, and with bapos confirming that it is based on road speed, not RPM, I would say that it is there to scare the driver.

If it were my bus, I would possibly install a tach, but would definitely reach under the dash and remove the bulb. Another option would be to install an "Interstate" switch to interrupt the wire to the bulb, so it could keep me honest on secondary roads (NYS 55 mph unless posted), and kill the warning when cruising the big roads.

[caseythenose]

Is the RPM on the 366 engine really tuned to the 3600 level?
I thought you could rev those to 4k with no issues at all.
In fact, we used to take the 454 to 5 grand all the time in the box truck climbing the hills.
It lasted 227,000 before it popped.
Regular non synthetic oil and pulling a trailer total weight was around 35,000 pounds if memory serves...so that thing was always quite taxed.

[bapos]

Like all things I think it depends on the gear your running. As I posted earlier I was buzzing in the 60 to 65 range and was revving in the 3500 range. The tach has no red zone or redline in it so not sure if that is good bad or indifferent. From what I have read these motors are work horses. They are made for torque so Im sure if they are altered their ability to last a long time will decrease.

I do also know they are an unbalanced motor so when I get a back up or have to redo this motor I plan on having it balanced to help it out. I am sure the life from motor to motor is all on a stop watch some will live longer than others but one thing I do know is using good parts, changing oil frequently, over all good maintence will make it last as well. I do not have a 100k digit on the odometer so I am pretty sure mine is at atleast 142k. I am of the mindset... if you take care if it... it will take care of you.