Phew! Learning about hyphens is way more complex than I anticipated when I clicked the link. I shall need to be careful with my link-clicking in the future.

 

Yesterday I went and got a rear output seal for the np205 and will see if the weather allows to do it tomorrow. We’re supposed to get quite a snow storm here so we’ll see. I wish I had a space to pull the truck into, but all I have is a concrete slab.

Today I compiled a list of things to do to it. not sure I’ll ever get it all done, but we’ll see! I want to mount a 5 speed back in the truck ASAP! It just was not meant for an auto and the 47rh wasn’t done the most proper way either. Seems I top out about 75 on a gps if I’m lucky. That’s with the torque converter locked too. Truck doesn’t seem like it is revving out, just like it doesn’t have the power to go any faster.

I need to get gauges soon so I can try tuning the pump a little. I plan to get it to where it either runs too hot and then turn it down some or just smokes too much. I don’t like having smoke rolling out my tailpipe or blacking our roadways. It’s not good for the truck and just makes people mad. I just want to be able to get up to 65 without giving heavy throttle input and in less than a mile as well. Here again I have another never-ending list!

 

The slippery slope we spoke about

Did you upgrade the pump to the 366 spring? No ?

That would explain the inability to go faster.

 

1stGEN'93,
If you can only go 75MPH, even without the 366 spring, you must have 4.10 gearing, or the O/D is not working on that 47 RH.
The OD gearing on the 47 RH is really close to the O/D gearing on the Getrag, so that will not fix the problem you seem to have with your MPH search.

Have you checked that you are actually getting full throttle movement from the pedal to the injection pump?..as in are the cable and / or throttle linkage not adjusted right and you are not getting all you should be?

 

According to the tag on the axles I have 3.54 gears. I don’t have a aftermarket spring. Overdrive kicks in VERY notably and it takes some time to build boost back up even with foot to the floor. I had a friend watch to see if the throttle hit the throttle stop and it didn’t quite touch it with pedal on the floor. Some days it will do 70 no problem, but others it struggles to do 70 and seems to never build boost for the longest time. I get even more frustrated with the 47rh being my o.d. is on one switch and my torque converter is on another. I’d rather push an extra pedal and have full control.

 

You need to replace the oem governor spring with the 366 spring, which will allow you to reach into the higher rpms. Technically it's a 3200 rpm spring, but it's imprinted 366 on it.

It will wake that engine up like no other..

 

 

So then your speed issue has nothing to do with your 47RH and is somewhere between an improperly working throttle linkage and likely a factor specced injection pump.

For a comparison my 93 with a 4.10 ratio will do about 85-90 mph. That as fast as one really needs to go while actually using a truck for towing.

 

If you have the OD working and 3.54 gears and can only do 70-75 MPH you have some other issue.
My '91.0 or RC with 3.54 gears and an working [Getrag] O/D has no problem doing more than that in 4th gear let alone in O/D.
It does not sound like a gearing issue to me, unless I am getting wrong info on the O/D working or axle ratio.

How is the fuel delivery system? Still full of greasy left overs?
What sort of boost #s are you talking?

 

Throughout the power band.

You won't believe the difference.

 

 

I wonder if you're suffering from low fuel pressure or a partially clogged fuel filter.

 

Mine runs better all the way from idle up. after the 366 spring install.

 

My first thought was Turbo.
black smoke ,no boost.

 

Well,

Now that you, I and Oliver told him to install the 366 spring, he will



Exhaust temp, fuel pressure, and boost are available from glowshift, in a 3 in 1 unit . I have it in my steering column, and it helps understand what's going on while I drive.