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Re: Red line value for the 4.2L CJ7 engine

Ya, but guys, guys, this is in '4TH' gear!!!

I do have 5th gear!

And I did just check it this morning on a highway run out to pick up a
cheque. I had the spedo pinned at 85 and I was just hitting 2700 rpm in
4th.

I have 'tons' of pedal left, it isn't anywhere near the floor at 85 in
4th. I guess I should have dropped it into 5th just to see how low it
revs.

My speedometer is also calibrated right on according to my GPS unit.

Mike

breyfogle wrote:
>
> >>> 85 mph in 4th is only 2700 rpm on mine. <<<< Wow! with a 4500 RPM
> redline, that gears out to 141+ MPH. ;-)
>
> I doubt my mostly stock '83 would be capable of exceeding 75 MPH in a free
> fall off the rim of the Grand Canyon.....
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:401E81F4.72FA2DAE@sympatico.ca...
> > No way....
> >
> > Mine will pull out to 55 mph at 4500 rpm in 2nd gear easily.
> >
> > Don't know where 3rd tops out at, but it is 'way' up there. 85 mph in
> > 4th is only 2700 rpm on mine.
> >
> > I am running the stock BBD carb, an Accel SuperCoil and a straight
> > exhaust with a dynomax super turbo muffler.
> >
> > All manually set up, I killed the computer.
> >
> > The computer acts like a governor and clamps down on the timing advance
> > so they run out of steam way before 4000 rpm, closer to 3500 and it hits
> > 'the wall'.
> >
> > Mike
> >
> > j carter wrote:
> > >
> > > And it's gonna be out of breath way before it gets there.
> > > (Let's hear it for AMC!)
> > >
> > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > news:401E7A69.427232ED@sympatico.ca...
> > > > 4500 rpm.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > >
> > > > William Oliveri wrote:
> > > > >
> > > > > Does anyone know what the red line value should be on a 4.2L engine?
> > > > >
> > > > > Thanks,
> > > > >
> > > > > Bill

Re: Red line value for the 4.2L CJ7 engine

I can believe that.....

I have a stock engine '79 with 33" tires, 4.10 axles and a T150 3 speed and
that runs out of steam about 4200 flat out which works out to just over 100.
I tested this early one morning doing a 60 mile journey 'at pace' (first 5
narrow British lanes, next 55 motorway (freeway)). I did the 60 miles in a
shade under 40 mins making a 90+ mph average.....pretty much what you expect
for a 100 mph top speed. I cannot of course condone speeding and all
applicable laws are for your own safety and should be adhered to!

Not sure how long the engine or tranny would last doing that all the time
though! Certainly a bit cruel doing it to a 25 year old block! Just needed
to know!

Paul

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:401E93C3.572C731B@sympatico.ca...
> Ya, but guys, guys, this is in '4TH' gear!!!
>
> I do have 5th gear!
>
> And I did just check it this morning on a highway run out to pick up a
> cheque. I had the spedo pinned at 85 and I was just hitting 2700 rpm in
> 4th.
>
> I have 'tons' of pedal left, it isn't anywhere near the floor at 85 in
> 4th. I guess I should have dropped it into 5th just to see how low it
> revs.
>
> My speedometer is also calibrated right on according to my GPS unit.
>
> Mike
>
> breyfogle wrote:
> >
> > >>> 85 mph in 4th is only 2700 rpm on mine. <<<< Wow! with a 4500 RPM
> > redline, that gears out to 141+ MPH. ;-)
> >
> > I doubt my mostly stock '83 would be capable of exceeding 75 MPH in a
free
> > fall off the rim of the Grand Canyon.....
> >
> > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > news:401E81F4.72FA2DAE@sympatico.ca...
> > > No way....
> > >
> > > Mine will pull out to 55 mph at 4500 rpm in 2nd gear easily.
> > >
> > > Don't know where 3rd tops out at, but it is 'way' up there. 85 mph in
> > > 4th is only 2700 rpm on mine.
> > >
> > > I am running the stock BBD carb, an Accel SuperCoil and a straight
> > > exhaust with a dynomax super turbo muffler.
> > >
> > > All manually set up, I killed the computer.
> > >
> > > The computer acts like a governor and clamps down on the timing
advance
> > > so they run out of steam way before 4000 rpm, closer to 3500 and it
hits
> > > 'the wall'.
> > >
> > > Mike
> > >
> > > j carter wrote:
> > > >
> > > > And it's gonna be out of breath way before it gets there.
> > > > (Let's hear it for AMC!)
> > > >
> > > > "Mike Romain" <romainm@sympatico.ca> wrote in message
> > > > news:401E7A69.427232ED@sympatico.ca...
> > > > > 4500 rpm.
> > > > >
> > > > > Mike
> > > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > > 88 Cherokee 235 BFG AT's
> > > > >
> > > > > William Oliveri wrote:
> > > > > >
> > > > > > Does anyone know what the red line value should be on a 4.2L
engine?
> > > > > >
> > > > > > Thanks,
> > > > > >
> > > > > > Bill

Re: Red line value for the 4.2L CJ7 engine