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 Post subject:
PostPosted: Thu Sep 25, 2014 10:49 pm 
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EFI Slant 6

Joined: Wed Sep 10, 2003 7:15 am
Posts: 285
Location: N. California
Car Model:
Sam Powell wrote:
Why does the rpm scale in the datalog only go to 2000? Does it display only the highest attained value? You have to assume it is trying to go higher and cannot.


That sure is what it looks like... repeated efforts of WOT, over and over, likely with some frustration thrown in... where the rpm simply won't go any higher.

What puzzles me is the time delay of the A/F ratio after lifting the right foot. I didn't go through it with a fine tooth comb, but in several of those cases, lifting the right foot results in immediate change in TPS and pulse width (as expected), a reasonably soon change in RPM (which suggests not in gear? OR maybe I can't see closely enough). But the A/F stays rich for another 0.5-1 second before settling back down to lean. Is that normal? Is that simply a function of how long it takes the exhaust to make it down the tube and the meter to respond?

Sorry, my only experience with A/F meters is the narrow band, both with a carburetor and factory EFI, but I certainly don't recall ever seeing a delay like this.

My question to the original poster, which many of you have alluded to, is what happens if you goose it in neutral, where there's no limitation of RPM based on road speed or friction or gearing? Will it, in fact, exceed 2000?

- Erik

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 Post subject:
PostPosted: Thu Sep 25, 2014 11:16 pm 
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Joined: Sat Feb 08, 2003 2:37 pm
Posts: 4194
Location: CA
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Wonder what size (and how many in the throttle body) injectors there are. May not be enough to support the engine, or fuel pressure may be dropping off. Wish the a/f scale went from 10-15 instead of 0-15. From what I can make out of the a/f scale though it's going rich at higher rpm.

Any chance a rev limiter is setup in the software of either mjlj or efi system? Set to right # of cylinders?


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 Post subject:
PostPosted: Fri Sep 26, 2014 12:47 pm 
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Supercharged

Joined: Sun Jun 04, 2006 4:53 pm
Posts: 4295
Location: Gaithersburg MD
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There is also the possibility there is an interference filter that is hitting its max in some way and rejecting legitimate rpm reads.

Sam

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 Post subject:
PostPosted: Sat Sep 27, 2014 10:27 am 
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EFI Slant 6

Joined: Wed Sep 10, 2003 7:15 am
Posts: 285
Location: N. California
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I also noticed that, assuming each sustained peak in the TPS graph equates to WOT, the height of those peaks is not consistent. The first couple are higher than all the others. Does that suggest mechanical slippage in the adjustment of either the throttle cable or TPS sensor? I'm wondering if the computer simply isn't "seeing" a true wide open throttle.

- Erik

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Lots of early Valiants and Barracudas have crossed my path.

Also a handful of other toys for variety now and then.


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 Post subject:
PostPosted: Sat Sep 27, 2014 12:29 pm 
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3 Deuce Weber

Joined: Fri Sep 10, 2010 1:25 pm
Posts: 70
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Sorry about not posting sooner. Went to drive the car two days ago but I think my starter relay went out... will confirm later.

This data log was taken will slowly driving on side roads around my apartment complex. The engine just didn't want to exceed certain RPMs while driving.

If I "goose it" haha it revs up just fine. Once I fix the starting issue I can post some WOT logs along with other logs where can I can explain what's going on.

Would have done some things on the car sooner but my other car really needed the resonators taken off :lol:

As far as wiring is concerned, I do have shielded cable running from the trigger sensor. Now thinking back some of my grounds my be questionable just because they don't all lead to the same place and then connect to the engine block.

A couple of my friends really are pushing me to go with megasquirt and it is kinda working. If it dosen't work after a few more months of trying I might try selling the throttle body efi and build a megasquirt 3 board with the money.

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 Post subject:
PostPosted: Tue Sep 30, 2014 11:38 pm 
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EFI Slant 6

Joined: Wed Sep 10, 2003 7:15 am
Posts: 285
Location: N. California
Car Model:
jacmifish wrote:
This data log was taken will slowly driving on side roads around my apartment complex. The engine just didn't want to exceed certain RPMs while driving.

If I "goose it" haha it revs up just fine.


So, it revs past 2000 rpm if it's in neutral? Well, that doesn't sound like it's being hampered by a software limiter, then....

If the rpm limit happens only when there's a load on the engine, it's related to production of power more than to simple speed. Lack of fuel is one obvious possibility... and believe it or not, I saw a very similar problem once with old dead spark plug wires. I put on brand new ones, and suddenly it had power at any rpm.

That just shows you've got to have the basics working completely, before worrying about fine-tuning the details. 8)

- Erik

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Lots of early Valiants and Barracudas have crossed my path.

Also a handful of other toys for variety now and then.


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 Post subject:
PostPosted: Sun Oct 19, 2014 1:59 pm 
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3 Deuce Weber

Joined: Fri Sep 10, 2010 1:25 pm
Posts: 70
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Okay I tried taking a step back with things. I went through some of the wiring going to ground from the ignition controller and sent that directly to the battery (-), rerouted the trigger wheel sensor wire away from some of the plug wires. Took it for a test drive and no real huge changes. After that I set the full timing table to 10 and drove it around. The car acted much better and didn't make any funny noises when I gave it the beans around 2300 RPM up to 3100 or so. It did seem to lack some power though in places.

I took a data log and am noticing that my idler air control valve in the EFI unit is opening when i believe it really shouldn't be. Going to post a question again on the professional products forum.


Total Time ~ 2:11
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 Post subject: Coil Replacment
PostPosted: Wed Feb 18, 2015 5:28 pm 
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3 Deuce Weber

Joined: Fri Sep 10, 2010 1:25 pm
Posts: 70
Car Model:
After installing a new coil pack the problem my misfire problem seems to be gone.

Still messing with the fuel and timing. Hope to record some video of the car soon.

Plan to be moving into my own house soon (fingers crossed) so I won't have to tip toe around my garage "not working on my car".

Random thoughts:
My fuel pump is super loud.
Been thinking about making a turbo manifold, when I get a chance.
Need seatbelts...
I learned that slant sixs can eat dip sticks. :roll:

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 Post subject:
PostPosted: Thu Feb 19, 2015 3:25 am 
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Board Sponsor & Moderator
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Joined: Mon Oct 21, 2002 11:08 am
Posts: 16451
Location: Blacksburg, VA
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Congrats! Look forward to hearing about future improvements/tuning.

Lou

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 Post subject: Back to work
PostPosted: Sun Nov 01, 2015 10:30 am 
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3 Deuce Weber

Joined: Fri Sep 10, 2010 1:25 pm
Posts: 70
Car Model:
Back to work on the car.

Since I last posted I bought a house and I'm free from apartment living forever! :D

Of course I bought a fixerupper and had to work on it for until now. Replaced all the flooring, toilets, painting, ect. While all along my car sat in the garage :cry:

A few things happened since I moved with the car.
I had a oil leak around the valve cover after adjusting the lash, even though I was very careful about how I tightened it down. A gentlemen named John Goodman on this site sold me his cast Offenhauser and that fixed the problem. John was a great guy, he even threw some misc. accessories for the cover.

The car still misfires like crazy, however not under certain rpms.

I pulled the plugs and noticed 4,5, and 6 are fouling.
Image

This is interesting because 4,5, and 6 go to an exhaust manifold which doesn't have an O2 sensor; 1,2, and 3 have and O2 sensor after they collect.

This is the coil and firing order if interested. Coil should fire A-C-B-A-C-B for the slant six firing order 1-5-3-6-2-4
Image

A friend of mine suggested rerouting some of my grounds to the engine block rather than a junction I have going direct to the battery. He suggested I might be creating additional ground loops at slightly different voltages.

I tried driving the car today in open loop control mode on the efi so it didn't pay attention to the O2 sensor; I also cleared all the "learned" adjustments the computer made previously. This seemed to make no difference. However, you can definitely tell when the cam starts to hit its power band in the later RPM's.

Hoping I don't have a more serious problem with compression but does anyone think I should check that? My thoughts on the three misfires are either all three cylinders have a compression problem or some strange electrical issue.

Regards,
Jacob

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 Post subject:
PostPosted: Sat Nov 21, 2015 4:01 pm 
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3 Deuce Weber

Joined: Fri Sep 10, 2010 1:25 pm
Posts: 70
Car Model:
I rented a compression tester at Autozone and took a reading with the engine cold.

Throttle plates open, fuel off, all spark plugs out, and ignition system off.

Got a reading of 90 to 92 psi on all cylinders, which as far as is low.

I haven't done a wet test but I plan to get the motor up to temperature and checking again.

When I was cranking the motor over it actually shot a few spark plug tubes out.
Any thoughts on those readings? My gauge could possibly be bad...

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 Post subject: Leak around the rings
PostPosted: Sun Nov 22, 2015 2:08 pm 
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3 Deuce Weber

Joined: Fri Sep 10, 2010 1:25 pm
Posts: 70
Car Model:
I did the test with another gauge and got the same readings. I hooked the gauge up to my compressor and verified the gauge and it read correctly.

Next I aligned cylinder 4 at TDC and applied about 30 psi to the cylinder and could hear bypass through the dipstick. I turned up to about 50 psi to hear it a little better and that rolled the motor over which opened the exhaust valve.

I did the same procedure on cylinder 3 with same results.

I took a video of the noise through the dipstick and I'm currently uploading it to youtube.

If there is similar bypass on all cylinders, would the mean the motor wasn't broken in properly or could all my rings have gone equally bad all at once?

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 Post subject:
PostPosted: Sun Nov 22, 2015 2:21 pm 
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3 Deuce Weber

Joined: Fri Sep 10, 2010 1:25 pm
Posts: 70
Car Model:
https://youtu.be/ILk6dVSUpn0

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 Post subject: Found the source...
PostPosted: Tue Nov 24, 2015 4:15 pm 
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3 Deuce Weber

Joined: Fri Sep 10, 2010 1:25 pm
Posts: 70
Car Model:
I believe I see the source of the issue now. After taking a step back and looking at my setup, I checked through some forums and found someone would typically buy the K1 connecting rods at a length of 7.005" with the weisco pistons. Since I never bought and had those installed by the builder I' still using the connecting rods for a stock 225 length of about 6.7...

I was pretty ignorant with this so I don't want to blame the builder too much...

That would explain the consistent but low compression on each cylinder.

I'm trying to weigh my options. Here is what I see I can do from here:
1. Tear down the motor and install new connecting rods.
2. Connecting rods with a spacer between the block and head + Boost? :D
3. Buy take the hemi out of my daily driver and put it in the Duster.

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PostPosted: Tue Nov 24, 2015 5:48 pm 
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Turbo EFI
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Joined: Mon May 12, 2008 1:11 am
Posts: 1473
Location: North Georgia
Car Model:
jacmifish wrote:
If there is similar bypass on all cylinders, would the mean the motor wasn't broken in properly or could all my rings have gone equally bad all at once?

I find it extremely unlikely all the rings would be bad. I have accidentally installed rings upside down and that did some wacky things, so that's a possibility, maybe?

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