'74 Argosy 20' Motorhome restoration/rebuild

[PeterH-350LE]

Originally Posted by bkahler

... I also added a fuel filter after the high pressure pump. I'm not sure if it should go before or after the pump and since I only had a filter for the larger 3/8" line on hand I opted for the latter

Brad

Cool, Brad, making great progress. I would put the fuel filter before the high pressure pump. But I really don't know if that has an impact on proper pressure regulation?

[bkahler]

Originally Posted by martin300662

That setup should be on display Brad.....you need a plexiglass dog house cover!

Know anyone that makes see though insulation?

[bkahler]

Originally Posted by PeterH-Airstreamer

Cool, Brad, making great progress. I would put the fuel filter before the high pressure pump. But I really don't know if that has an impact on proper pressure regulation?

I'm not sure either. I'll do some research this week to see what's considered best practice.

It's amazing how much time it took to fabricate the throttle cable bracket, MAP sensor bracket and the coil bracket. I probably have 2 days wrapped up in all the nit picky little details in trying to get those three brackets to fit and work with each other


All that's left now is to install the TBI harness and make the appropriate external connections for ground and power. That will have to wait until Tuesday or Wednesday due to the need to mow tomorrow after work.

[jonesy 1]

I move those coils off the motor ,they last longer accel makes super electronic with a pig tail .

[bkahler]

Originally Posted by jonesy 1

I move those coils off the motor ,they last longer accel makes super electronic with a pig tail .

Yeah, I was considering doing that but didn't want to make that decision until the engine is install in the chassis.

[wxbuoy]

Great job! Although you lost me after "The space between...." 😜


Sent from my iPhone using Airstream Forums

[bkahler]

Originally Posted by wxbuoy

Great job! Although you lost me after "The space between...." 😜

Dave, I'm not to far behind you on that.....

[bkahler]

I don't know that I ever shared this picture before


Not sure why some PO decided it was important to let the passenger know that the Argosy was protected by WD40 but they did

I can't say that the WD40 did much good as there was still a good bit of rust to deal with.

[martin300662]

Somehow the Engineering Flowchart never seemed more appropriate.

[bkahler]

I believe the PO also had issues with movement as there were plenty of duct tape remnants found as well!

[bkahler]

Another milestone day today

I finished up the TBI test stand installation and was able to get in several test runs while logging data.

Here's the first run. I didn't set the initial or base timing for this run because I forgot too so this run was set with fairly advanced base timing.

https://youtu.be/jsx9tBB4vYs


Here's the 2nd run. I did the timing by ear and it helped a good bit, especially for starting.

https://youtu.be/n7N7YPPZCV8


And here's the last run that I made. This time I had set the base timing to 6 btdc. I wasn't to far off from where I set it by ear but it's nice to know it's where it supposed to be now.

https://youtu.be/481oyU3EYhk


I'm definitely impressed with the TBI setup. At the moment while trying to start the engine on the first rotation it acts somewhat like it is to far advanced but it starts up almost immediately after that first hesitation. The idle his bouncing slightly and I'm not sure if that's the RV cam doing that or the TBI not having been tuned yet. At just about any speed the rpms seem to hunt a little bit and again my guess is that will go away once it's tuned.

Engine temperature seemed to maintain itself better and I never saw the logged temperature go above 199.6. The mechanical temperature gauge located in the left head shows temperatures very similar to the sensor used by the TBI although it does go a few degrees higher after a prolonged idle.

It would appear the guy I'm using for tuning knows his stuff. The code he sent seems to be working really well. I should be getting an updated version tonight or tomorrow.

With luck I'll be able to wrap up this portion of the TBI project and start tearing down the test stand next week. I'd really like to have the 454 mounted in the chassis by the end of the 4th of July weekend!

Brad

[PeterH-350LE]

Looks good, Brad. I assume you have to revisit the fine tuning once you put the engine under load. At least I concluded that the AF at idle is one thing, but the real test comes at different RPM's under load. I was very pleased to see ~14.5-15.0 at 50-60 mph.

[bkahler]

My guess is I'll have to revisit the tuning 3 or 4 more times at least. I expect the next program he sends will smooth things out for how it sits on the test stand.

After that he will send me another program that has the 4L80e enabled. I won't be able to test that program until I get the engine and transmission installed, drive shaft shortened, gas tank installed and the rear suspension reworked. At that point I should be able to go for a test drive! I'm hoping to reach that goal by Thanksgiving.

That goal also means I've got a lot of chassis wiring to do along with installing the new instrument cluster!

Brad

[german6563]

Brad that's good music to my ears to hear that engine as it works
Congratulations
Herman

[bkahler]

Originally Posted by german6563

Brad that's good music to my ears to hear that engine as it works
Congratulations
Herman

Thanks Herman!

I could be wrong but it seems to sound a little different running with a TBI system than it did with a carburetor. I know it definitely starts faster.


Brad

[Gregsch]

Outstanding! You are really making great progress Brad. I think you are working on the most practical drive line upgrades possible. I am anxious to see your performance and mileage numbers when you get everything dialed in. I think you are blazing the trail for many others to follow. I think few would argue that the Cummins swap is the ultimate upgrade but, what you are doing can be done for a fraction of the cost.

[bkahler]

Thanks Greg!

I thought about the Cummins conversion and realized I didn't have the deep pocket book needed for that sort of job

I really like the fact that just about all of this is bolt on. I've had to fabricate a few things like the throttle body adapter and various brackets but overall just about everything else is off the shelf.

I'm really looking forward to being able to drive the Argosy for the first time. Time will tell if I can make my Thanksgiving dead line

Brad

[bkahler]

I've been playing with various tunes provided by my tuner. We're having an odd problem that neither he or I can explain. At first I just assumed the problem was in the tuning and would be resolved as he worked through the tuning process. However I went back and reviewed all of my log files and found the same situation occurring above idle and below roughly 2000 rpm.

A quick spike is occurring in the RPM input signal which in turn seems to cause a spike in the Spark Advance to the distributor. I've attached some data log graphs showing the RPM spikes and the Spark Advance spikes. I really don't see how this could be related to tuning since the RPM input comes from the distributor. Revving from idle to above 2000 rpm is somewhat of a struggle as the engine wants to bog down somewhat. But once you're above 2000 it wants to rev like crazy!




I have a spare PCM, memcal, and distributor ICM module so I will probably try substituting components to see if the spike goes away.

Any thoughts or suggestions?


Brad

[martin300662]

Originally Posted by bkahler

I've been playing with various tunes provided by my tuner. We're having an odd problem that neither he or I can explain. At first I just assumed the problem was in the tuning and would be resolved as he worked through the tuning process. However I went back and reviewed all of my log files and found the same situation occurring above idle and below roughly 2000 rpm.

A quick spike is occurring in the RPM input signal which in turn seems to cause a spike in the Spark Advance to the distributor. I've attached some data log graphs showing the RPM spikes and the Spark Advance spikes. I really don't see how this could be related to tuning since the RPM input comes from the distributor. Revving from idle to above 2000 rpm is somewhat of a struggle as the engine wants to bog down somewhat. But once you're above 2000 it wants to rev like crazy!

Attachment 264933Attachment 264934Attachment 264935Attachment 264936


I have a spare PCM, memcal, and distributor ICM module so I will probably try substituting components to see if the spike goes away.

Any thoughts or suggestions?


Brad

Sounds like something is causing debounce Brad, and the signal averaging period isn't long enough (ie the signal to advance the distributor is being made before the debounce has been averaged out). If it is you have two choices....chase the source of the debounce or increase the averaging period on the decision to advance. The first option would be the purist view, because the second will slow responsiveness slightly - but are you going to be street racing this thing!!!!!

[bkahler]

Originally Posted by martin300662

Sounds like something is causing debounce Brad, and the signal averaging period isn't long enough (ie the signal to advance the distributor is being made before the debounce has been averaged out). If it is you have two choices....chase the source of the debounce or increase the averaging period on the decision to advance.

I need to ask the tuner if the program uses different averaging periods for different RPM ranges. I wouldn't be surprised if that was the case. Also thinking along those lines I wonder if it's possible the number for the averaging period may have been entered incorrectly or inadvertently altered. I'll query him about this idea. However that idea might not be the answer because I do know we've tried memcals from two different vehicles and both are exhibiting the same exact behavior. The first one we tried was from a very similar engine configuration that is in use and running on the street right now. The second is from a 1994 454 P30 motorhome.

The only thing that is the same is I haven't as yet substituted any of the electronics hardware.

The first option would be the purist view, because the second will slow responsiveness slightly - but are you going to be street racing this thing!!!!!

Hmm, define street racing.....