Coast Resorts Open Roads Forum: How many of us are there? Owners of Dodge based RV's?

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Topic: How many of us are there? Owners of Dodge based RV's?

Posted By: overdrive75 on 11/04/08 05:06am

Well, I figured out my speed issues yesterday. This after installing a tachometer on Sunday. The three speed trans in not enough. It needs a 4 speed. At 60 mph the motor is spinning 3000 RPM and at 65 it is spinning 3200. This thing needs a 4th gear to get the motor back down to a speed where it is making some torque. Oh well that isn't going to happen, so I guess I need to slow down a bit.

* This post was edited 11/05/08 10:45am by overdrive75 *

Posted By: 79powerwagon on 11/05/08 03:04am

overdrive75 wrote:

Well, I figured out my speed issues yesterday. This after installing a tachometer on Sunday. The three speed trans in not enough. It needs a 4 speed. At 60 mph the motor is spinning 6000 RPM and at 65 it is spinning 3200. This thing needs a 4th gear to get the motor back down to a speed where it is making some torque. Oh well that isn't going to happen, so I guess I need to slow down a bit.

Can you correct your typo please? [emoticon]

And run a vacuum gauge while you drive, it'll help you find the operating "sweet spot"...

She ain't purdy, but at least she's slow!

Posted By: Fezziwig on 11/05/08 10:02am

(I'm just unsubscribing, sorry for the interruption)

Posted By: timmac on 11/06/08 12:06am

Does anyone know how many cfm's a stock 440 radiator fan pulls, I am thinking of installing a double electric fans that pull at 4600 cfm with a shroad, I have a 4 core super cool rad now, will this work or will I need more cfm's..
Flex o lite has the double electric fan, stock number 295 "4600 cfm max",,, they also have a 5500 cfm double fan but its 4 inches to wide for the 79 Dodge rad.

Posted By: 79powerwagon on 11/06/08 03:04am

OD, you can change your gear ratio a bit by installing taller tires on the rear. But before you do that (or call Gear Vendors), hook up a vacuum gauge and drive around a while to see how it responds to your driving habits.

An example, if your driving at 60 and 3000rpms, and you're pulling 15"hg, and then you're driving at 65 and 3200rpms and pulling 17"hg, you are actually MORE efficient at 65 than 60. If the opposite were the case, then you are more efficient at 60mph...

Get what I mean?

Eric

Posted By: RobinHoodRV on 11/06/08 11:24pm

79powerwagon wrote:

Correct me if I'm wrong but how could you get higher manifold pressure if the only factor that changes is increasing throttle position to increase the RPMs? Wouldn't the increased throttle position lower the manifold pressure?

My understanding is that throttle position on a non-computerized, carbureted vehicle determines manifold pressure. I don't think I have ever seen pressure increases while throttle positions increases unless other factors are involved, like gear changes, or in the instance of newer vehicles timing changes due to computer control, etc.

This is just my understanding and would be very interested in the correct information!

-jc

78 Robinhood 23' Class C
97 Geo Tracker Convertible 4x4
87 Jeep Comanche Chief 4x4

Posted By: 79powerwagon on 11/07/08 03:14am

Roninhood, the vacuum gauge shows how hard the engine is working. The higher the reading, the less work it is doing (more efficient use of air and fuel).

I did a little experiment with my Power Wagon. There is a spot I drove daily where the road has a sharp "S" curve that climbs rapidly up several 100 feet (common terrain around here). My truck always had enough power to navigate that spot without down-shifting.

My installed vacuum gauge (doesn't everyone run one in all their vehicles? [emoticon]

) would show something like 7"hg going through there.

Just for giggles, one time I manually put the truck into 2nd gear going through there, traveling at the same speed I always do if the road conditions are dry. The vacuum gauge jumped up to 18"hg!

So, while the truck moved at the same speed each time, in 2nd gear, the engine was working MUCH less than in 3rd, and was more efficient, even though the rpms were considerably higher.

No two vehicles are the same, and no two drivers are the same. If you spend the $30.00 or so on a dash mounted vacuum gauge, and learn how to read it AND how to interpret it as you are driving, you can actually save gas money by utilizing the engine at it's best available efficiency!

It really does work! As a bonus, you also get an instant read on the mechanical condition of the engine and what kind of shape your tune-up is in BEFORE you need to spend the big bucks in repair!

Of course, this applies mostly to carb'd engines without computer controls, but you can still learn a lot about your driving habits on an EFI vehicle.

Eric

Posted By: overdrive75 on 11/11/08 12:00pm

So my RV has a rather large class III or IV hitch on it. I can't tell as the lables are faded, however the hitch is newer than the coach. The PO must have only used this for a bike rack as there was no trailer wiring whatso ever. So a few days ago I handled this situation. I thought I would tap the wiring in the back near the lights, but after pulling those off, I decided against this as there was no easy way to route it out of the coach body. So next I looked up front under the hood for the wiring and could not find it. So I start looking around inside the cab, and low and behold there is a small fuse pannel behind the drivers seat for the 12V coach wiring, Left, right, running and back up. Well I didn't want to tap it after those fuses, once again no easy way to get it out of the body. So I start looking under that dash and I find the wires before those fuses, so I tap them under the dash, run the wires out through the fire wall, install separate fuse pannel for run, left and right trailer. I install separate ground and run the 4 flat wire from under hood all the way to back. At the same time I ran a wire for electric brakes and left it hid under the dash. At the back there is a 7 pin plug all wired up and ready for use, with even a 12 volt hot from the coach battery. The only thing missing is the reverse light but non of my trailers have that. So now I am good to go on that front. The only think I really want to do is totally isolate the trailer wiring, but I don't know how yet. But it all works.

Posted By: overdrive75 on 11/16/08 05:57pm

Well, it's official, 2008 camping season is over for me. We got 4+" of snow today and they have put salt on the roads, so the RV is parked. I have had her tarped for the winter for the past 1.5 weeks, but today just really made it real.

Can't wait till next year. I still need to fog the motor and pull the batteries for the long winters rest.

Posted By: ALnCORY on 11/18/08 11:04am

Sorry Overdrive, getting on to winter here too. No snow down in the valleys but lots of white on the mountains. Still some folks out hunting with campers but its slowing down..... but hey, spring is coming..... eventually.

I don't think anyones dying statement ever contained the words "I wish I had spent more time in the office", so lets go somewhere!

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