top speed

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lserd.oldrp
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Re: top speed

Post by lserd.oldrp »

bobbyr wrote:I drove my trooper to fort Jackson two weeks ago I run it up to 85 mph at 3500 rpm I changed my gearing from 455 to 410 with p235 tires so it is geared a lot better for high way driving

Consistantly ? , dare I ask what it was at with a455? man no wonder they blow rods out the side !!!!!!!!!! Must have been scremin. 3500 RPM! wow!

watch me eat my words with a tach in stalled, and the large tire, wonder what the rrrrrrrrrrrrrrrrrrrrrr S' are ?
1984 Isuzu pup N/A 2.2 Diesel 5 speed 3.42 gear Short bed.
Up grade's gt2052 turbo, 86-87 volvo inter cooler, 4'' cold air intake, 3'' Exh. aero diesel turbine muffler.
Pupfocused
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Re: top speed

Post by Pupfocused »

bobbyr wrote:I drove my trooper to fort Jackson two weeks ago I run it up to 85 mph at 3500 rpm I changed my gearing from 455 to 410 with p235 tires so it is geared a lot better for high way driving

How is the trooper driving around town and on steep grades with the 410 gears. I have always thought about changing the gears on my trooper.
Thanks
Jim
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1985 4x4 diesel pup
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bobbyr
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Re: top speed

Post by bobbyr »

I live in western nc so we have a lot of hills here I don't have any problem at all with 410 gears in my trooper
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Re: top speed

Post by nucleus »

quicknotslow wrote:
OzarkDaredevil wrote:Larry, I see a big turbocharger in your future...



The turbo is nearly ready, just don't know what I'm going to put it in. :mrgreen:


My vote would be put it back in that cherry space cab of yours!! 8)
1991 4X4 Pickup powered by a Gen 3 Trooper Turbo Diesel engine built by Jerry Lemond. 5 Speed Trooper MSG tranny behind the engine.
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trooper T/diesel
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Re: top speed

Post by trooper T/diesel »

the nut behind the wheel needs to be un---cross threaded....
soot fart wrote:if god had intended for us to drive automatics, he wouldn't have given us two feet


rust free frame 1981 4wd luv for sale no engine\trans Cliky to see

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quicknotslow
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Re: top speed

Post by quicknotslow »

trooper T/diesel wrote:the nut behind the wheel needs to be un---cross threaded....





:? :?:
Larry




1982 LONG BED DIESEL
1986 TURBO SPACE CAB With 59034 Miles
mmmorphine
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Re: top speed

Post by mmmorphine »

Apparently mine runs better than I thought. The fastest I've actually been is around just under 80, but still had plenty of throttle left. I'm usually running around 65 because I'm so afraid of breaking it for some reason. What is a relatively safe speed to sustain for long periods of time like a 100 miles or more. My truck is an 84 P'up, diesel N/A, five speed, two wheel drive long bed. The truck has just over 90,000 miles, but had been well maintained.
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Re: top speed

Post by FiatSpider2 »

mmmorphine wrote:Apparently mine runs better than I thought. The fastest I've actually been is around just under 80, but still had plenty of throttle left. I'm usually running around 65 because I'm so afraid of breaking it for some reason. What is a relatively safe speed to sustain for long periods of time like a 100 miles or more. My truck is an 84 P'up, diesel N/A, five speed, two wheel drive long bed. The truck has just over 90,000 miles, but had been well maintained.


Regardless of how much throttle is left you need to observe engine redline on the tach. A pushrod diesel usually has a MAX RPM of around 2,800 to 3,600 RPM so for cruising on the highway you really want to stay at 2/3 to 3/4 of redline as once you get to redline you have a higher chance of scuffing the bearings, snapping connecting rods, etc. I have an overhead cam 4FB1 in my car and even with its much higher redline 75 MPH is really pushing the limits of the RPM range.
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JoeIsuzu
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Re: top speed

Post by JoeIsuzu »

FiatSpider2 wrote:
mmmorphine wrote:Apparently mine runs better than I thought. The fastest I've actually been is around just under 80, but still had plenty of throttle left. I'm usually running around 65 because I'm so afraid of breaking it for some reason. What is a relatively safe speed to sustain for long periods of time like a 100 miles or more. My truck is an 84 P'up, diesel N/A, five speed, two wheel drive long bed. The truck has just over 90,000 miles, but had been well maintained.


Regardless of how much throttle is left you need to observe engine redline on the tach. A pushrod diesel usually has a MAX RPM of around 2,800 to 3,600 RPM so for cruising on the highway you really want to stay at 2/3 to 3/4 of redline as once you get to redline you have a higher chance of scuffing the bearings, snapping connecting rods, etc. I have an overhead cam 4FB1 in my car and even with its much higher redline 75 MPH is really pushing the limits of the RPM range.

My factory tach has a redline of about 4,250 RPM, best I can tell. He should have the same gear ratios I originally had. Somewhere in my post history, there are pics of the RPMs at various speeds. I don't recall any of them specifically, but I remember it did not hit the redline at 85 mph, or even beyond. I'll see if I can dig up that topic.

Jack
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Re: top speed

Post by JoeIsuzu »

It turns out, I did not get a pic of the tach before my transmission upgrade. But I'm pretty sure 60 MPH (indicated) is about 2,500 RPM for 5-speed diesels with the stock 3.73 rear end. That means 80 MPH would be about 3,300-3,400 RPM.

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Re: top speed

Post by Halden »

I have put thousands of miles on my 4x4 at redline doing around 80... the engone wasn't in the best of shape when I got it so I figured I couldn't hurt it... The diesels can turn that all day long but you'll experience faster wear... Regularly cruised at 65... Didn't seem to mind it.

My 5 speed I cruise around 60 just because I get such good mileage around that speed. Maybe the ideal would be consistently no higher than about 3200 rpm which is about 75mph. Diesels are kinda born to just run hard. They generally like it a little better.
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Re: top speed

Post by FiatSpider2 »

Halden wrote:I have put thousands of miles on my 4x4 at redline doing around 80... the engone wasn't in the best of shape when I got it so I figured I couldn't hurt it... The diesels can turn that all day long but you'll experience faster wear... Regularly cruised at 65... Didn't seem to mind it.

My 5 speed I cruise around 60 just because I get such good mileage around that speed. Maybe the ideal would be consistently no higher than about 3200 rpm which is about 75mph. Diesels are kinda born to just run hard. They generally like it a little better.


The overhead cam 4FB1 redlines somewhere over 5,000 however do you really want reduce engine life to 1/2 or 1/4 of its potential? In application you really don't want the even get into the yellow zone of the OEM tack for the engine. If the truck originally had a gas engine and was converted to diesel you definitely don't want to go by the the redline on the tach. Mine shows 7,500 rpm but thats meant for a DOHC Italian Gas Engine and not the 4FB1.

Can't find a definitive document about redline on the 2.2 pushrod engines only charts showing that MAX HP and Torque are developed at between 2,700 and 3,000 RPM depending on series and that power drops off very quickly once past those RPMs.
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Re: top speed

Post by Halden »

FiatSpider2 wrote:
The overhead cam 4FB1 redlines somewhere over 5,000 however do you really want reduce engine life to 1/2 or 1/4 of its potential? In application you really don't want the even get into the yellow zone of the OEM tack for the engine. If the truck originally had a gas engine and was converted to diesel you definitely don't want to go by the the redline on the tach. Mine shows 7,500 rpm but thats meant for a DOHC Italian Gas Engine and not the 4FB1.

Can't find a definitive document about redline on the 2.2 pushrod engines only charts showing that MAX HP and Torque are developed at between 2,700 and 3,000 RPM depending on series and that power drops off very quickly once past those RPMs.


The 2.2 (for automotive use) develops max HP at it's redline of 4300. 4fb1 redlines at 5000 where it's max HP occurs. Generally with a diesel that's how you get more HP, you just turn it faster by adding more fuel (over simplified). 4300 rpm honestly isn't really that fast for those tiny little rods and pistons especially with no boost... They barely flinch if at all. Especially with how meaty the bottom end and shallow stroke. Even shallower on the 1.8... The only way to exceed redline is to gear down too far at too high a speed or crack the pump open and modify the governor.

I'm not sure where you're getting data from to talk about 1/2 or 1/4 life. If it's maintained and healthy it's not going to hurt it. Yes you'll experience faster wear but nothing major.
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
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Re: top speed

Post by FiatSpider2 »

Halden wrote:
FiatSpider2 wrote:
The overhead cam 4FB1 redlines somewhere over 5,000 however do you really want reduce engine life to 1/2 or 1/4 of its potential? In application you really don't want the even get into the yellow zone of the OEM tack for the engine. If the truck originally had a gas engine and was converted to diesel you definitely don't want to go by the the redline on the tach. Mine shows 7,500 rpm but thats meant for a DOHC Italian Gas Engine and not the 4FB1.

Can't find a definitive document about redline on the 2.2 pushrod engines only charts showing that MAX HP and Torque are developed at between 2,700 and 3,000 RPM depending on series and that power drops off very quickly once past those RPMs.


The 2.2 (for automotive use) develops max HP at it's redline of 4300. 4fb1 redlines at 5000 where it's max HP occurs. Generally with a diesel that's how you get more HP, you just turn it faster by adding more fuel (over simplified). 4300 rpm honestly isn't really that fast for those tiny little rods and pistons especially with no boost... They barely flinch if at all. Especially with how meaty the bottom end and shallow stroke. Even shallower on the 1.8... The only way to exceed redline is to gear down too far at too high a speed or crack the pump open and modify the governor.

I'm not sure where you're getting data from to talk about 1/2 or 1/4 life. If it's maintained and healthy it's not going to hurt it. Yes you'll experience faster wear but nothing major.


Real life experience with speed demons who wear out 500,000 and Million Mile Diesels in 250,000 miles or less. The candle that is burned more brightly burns out more quickly which is a simple fact of life. There is only one road to my knowledge in the USA with an 80 MPH speed limit which is in the boondocks of Texas and a Light Diesel Mini-Pickup that is already 30 to 40 years old is really not the best choice for driving on that road at the posted speed limit.

Folks used to gasoline engines lasting less than 200,000 miles somehow think that 250,000 from a diesel is pretty good however that is 1/2 to 1/4 of its potential life. Some too are only fixated on RedLine however there is also the theoretical YellowLine where accelerated engine wear begins and then OrangeLine where wear plus damage begins to accumulate more quickly before you get to the potentially catastrophic RedLine.

Remember RedLine is the max speed before catastrophic engine damage starts to occurr which is different from its Power Curve where MAX HP is developed. Of course as the engine ages and gets some wear on it then being near RedLine is going to more readily scuff bearings than when they along with the oil pump were new.
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Re: top speed

Post by Dieselsmoke69 »

Ive ran my 82 Luv Mikado c223 with 205 tires downhill spedo pegged.... briefly... its ok at 70 hwy all day in 5th but seems happiest at 55 in fourth. The 205s corrected the 5mph discrepency my msg5 upgrade from a 95 pup created when running the stock 195 tires. Hills....well thats another story lol. Why my build is getting a turbo and cyroed rods and valvetrain componets, that and my 38 year old engine smokes more than me cheech and chong sittin together in a space cab at the stop lights lol. Now that i know and respect what i have i try to take it easy on it. Its 38 years old and still running.....daily yeah. The whole reason i have another c223 on the stand now. Not skipping anything. I dont plan on running it to hard. Just for a very long long time. I could have put an LS or a tTDI in it or even a 4jb1 for what its costing me. But the rear end and brakes let alone fab work says no. The truck wouldnt be the same. If it aint broke dont fix it
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