Tom - Good idea about the IAC, but unfortunately that wasn't the problem.

I drove the car around for the past few days, all seemed well. Still need to get another speedo in. But I was in the driveway tweaking the timing, and suddenly I hear this clanking sound.. first words out of my mouth were oh sh*t! Seemed to be coming from the back of the engine... I took the valve cover off and all seemed well. then I ran the motor again and when i put my hand on the oil pan you could feel something banging against it. So now I have to pull the oil pan to see what is making the mystery noise. I thought the oil pickup may have fallen into the pan or something but I still get oil pressure (well, the idiot light didn't come on...) We'll see...

initially I had thought the efi was wigging out and went lean, causing detonation. Thought I had put a hole through a piston or something. Who knows... I just hope i don't drop the pan and see a piston in it.

Well I finally got in contact with the guys at howell again. They are going to send me chip #4, even leaner yet. When I get the engine back together and installed, I'll give that a whirl and see what happens. Hopefully this weekend the engine will go in. If this chip doesnt do it.... I am going to have to see what their return policy is. I've given this kit enough of a chance by now, don't you think?

Well its been a while since I updated this, so if anyone is curious...

Engine is back in and running, but still does the same thing with chip #4. I found one (possibly) loose wire between the magnetic pickup and msd box. I thought I had the distributor hold down screw all the way down so the distributor could not move out of the engine, but apparently I was wrong. I checked my timing and it was over 30+ degrees off 0. So I got the distributor in snug and set timing to 13ish deg advanced, and it ran remarkably better! Now instead of rpm jumping +/- 250 rpm (sometimes it was more like +/- 4 or 500), its at about +/- 100 to 150 (all readings centred around what seemed to be a set idle speed of 700rpm). I observed the engine shaking slightly, nothing major at all in fact I think it was like that before this whole efi business even began.

So I decide to adjust the valves to stock spec, and gapped the plugs to 45 (was running at 40 before). Some valves were tight but most were loose. Interestingly enough this made things run slightly rougher, I had to set timing to about 18deg to make it as smooth as it was before I did the valves and re-gapped the plugs. The slight +/- 100rpm variance still there, maybe slightly worse. I think the next time I am going to work on it I am returning the plugs back to 40, and if that doesn't do anything I might loosen the valves by .001 to get it closer to what it was before I touched the valves.

I think I may come back to investigating the iac some more. From the manuals I have read idle speed is supposed to noticeably change if it is unplugged, which it doesn't at all. Or we come back to the idea that if the mixture is so far off the iac won't make a difference... but if it was that far off the engine wouldn't be running as decent as it is now.

So after chip #6 or 7 I gave up on howell and decided to go MS route.

As of now, the MS main computer is assembled and tested with the Stimulator, and I just completed the relay board. Also went to the wrecking yard today to get some connectors so I can remake the harness. Also picked up injector resistor packs from a honda as mentioned in the MS forums - nice compact unit thats already heatsinked. Made for 4 injectors but no reason you can't use it on just 2.

I don't think I'll take pictures as I'm sure you all have seen the assembeld pics on the MS site, but once everything is in I'll snap a few.

Wholly shnikes I just realized that its been over 2 years with the howell system by date of my first post in this thread. The performance of the howell system just kept degrading, in the past few months instead of just an unsteady idle the car would just die. I even put the older chips back in just to see what they'll do and they also caused the car to die. Hopefully the MS will treat me well.

Did Howel do anything for you, or did you have to eat the whole deal?

_________________
Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

What a mess. There is no replacement for tunability (except for maybe Bob Ds MAF setup).

You will be happy with the MS setup, methinks... It's just sooo nice to have 100 engine parameters at your fingertips as you sit in the drivers seat.

I recommend getting a friend to drive the car while you tune the VE table, or just datalog a bunch of params with O2 feedback off (O2 sensor, inj PW/duty cycle...) while driving around at different rpms/loads. Then look at the datalog and tune VE. Lather, rinse, repeat.

Even easier, I've heard, is using MegaTune and datalogged values to tune the map automatically. I haven't done this as I like to see the tuning process unfold, and I just haven't bothered...

I'm about to get my second MS car running this week, this time with MP-EFI (64 is TBI).

Have fun,

Lou

_________________
Home of Slant6-powered fun machines since 1988

Charrlie, the chips howell resent me were all at no charge. I never inquired about returning anything because I'm reusing everything from the kit except the harness in my MS conversion. Plus being 2 years later I doubt they'd take anything back anyway

Lou, haven't done much with megatune yet except test w/stimulator, I'll have to look into its features more indepth

After doing all my makeshift-for-test-only wiring just to hear it run, setting the constants... it came to life under megasquirt power.

Only ran it for a minute or so to make sure everything was ok, then had to call it a day because I ran out of daylight. More to come next weekend.

Took a few test drives in it today around town, will be taking it on the freeway tomorrow. I'm liking it... not once did it stop or stall. Still need to work on the idle to get it 100% but its more then driveable just with the default settings (for a 350 chevy v8) except for the Required Fuel Field.

Man this thing has tweaks galore.... The manual suggests to turn on o2 feedback only after say 1300 rpm and richen up the idle area of the fuel map for a steady idle. Thats what I'm going to be working on next.

I ran MSTweak3000 and I think the fuel map is as close as its going to get with the narrowband sensor... I'm pondering a Innovate Motorsports wideband unit ... $200 for sensor/controller/cable that you can hook to megasquirt and tune ala wideband to your hearts desire....

For anyone pondering MS and consisdering your options... man I can't praise this thing enough. Its pretty sweet having a laptop in the car and making adjustments on the fly.

Nice work, Pierre. Keep in mind that you can get a lot more info from a NB O2 sensor than most people think. I use datalogging and shoot for 0.85-0.95V at WOT, and that seems to sit pretty well with dragstrip performance.

Hey, if you have the dough then go for the WB, though. I will do that eventually too.

Lou

_________________
Home of Slant6-powered fun machines since 1988

Lou,

I orderd the $200 wideband kit I mentioned by Innovate Motorsports, LC-1. It includes the bosch wideband sensor used on VW, and a cable with the controller built in. This allows for direct hookup to megasquirt. If you want a meter to see the ratio on a display, then the kit is $350. Apparently these are popular items as finding them instock isn't easy. Summit website says won't ship until 6/12, called jegs and lucked out they had one instock.

I think something is tweaky with my 4wire heated NB sensor. It seems to randomly go lean, either that or its cooling off (perhaps the heater isn't strong enough? Sensor is near the transmission belhousing, that topped with clifford shorty headers may still make it too cold even with heater). The wideband should take care of that, as those can be used at the end of the tailpipe even.

Yeah, that may be a little far downstream. Mine are 15-18" from the head ports and heat up w/in 2-3 min.

Lou

_________________
Home of Slant6-powered fun machines since 1988

At Pierre's request, I have now uploaded my .msq parameter files from my 68 and 64 Darts onto my (primitive) webpage.

Look in:

http://home.nc.rr.com/madsenkaestle/64%20Dart%20270/

and

http://home.nc.rr.com/madsenkaestle/68%20Dart%20270/

The files are called "megasquirtBLAHBLAH.msq".

Thanks,

Lou

_________________
Home of Slant6-powered fun machines since 1988

LC-1 kit installed and running. Other then a few minor issues (appropriate temp sensor) the MS setup is up and running.

Tried Lou's calibration files but engine wouldn't start with either one, even after altering the required fuel to suit my injectors. I have a feeling they may not work with my MS (version 3.00 firmware, whereas Lou's is 2.0 iirc?).

Strangely enough even after all the fiddling I did with the tables, the stock out of the box settings worked the best! The only changes that had to be made were relative to the different injectors I was using (2x 45lb/hr each gm tbi). From the stock settings I changed to 6 squirts/engine cycle, alternate injector squirting, 2 injectors, and used a required fuel of 9.0 (calculator said 8.7, 9.0 seemed to idle a bit better). Then I was off to the races....

Wideband really spoils the art of tuning - ego correction does it all for you pretty much as long as the map isn't insanely off. I ran some datalogs and played them back through the live log viewer ... heres a snapshot




Ignore the whacky coolant sensor... thats what I'm working on next. Notice how the A/F ratio sits pretty close to 14.7:1 for the most part, and dips into rick territory upon TPS change (accelerator enrichment kicking in, also goes rich upon deceleration until the MS catches up to what the o2 sensor is feeding it). I have set ego correction to start only at 1300rpm and above, thats why in the last third of the log the A/F goes a bit nutty. I'm idling at 12:1ish afr.

Thats the only way I can get a good idle.... I'll have to work on this in the future and see if I can get a good idle without being so rich. Try to lean it out and it stumbles. Tried to open the throttle blades more with the stop screw, but then idle was too high all together. May have to start playing with timing again - or perhaps I should back off the stop screw to close the throttle blades more and then lean it out - that may provide for a leaner idle thats still steady. Ah, something to play with next weekend.

For anyone interested that isn't tired of this thread yet - 18mpg during my past 74 mile trip, I'd say about 80% freeway. 3.23 rear gears, 904 tranny.