New MS3 install for my L28ET

[Sam280Z]

If it ran fine with the Z31 ECU, it should work fine with the MS3.

 

Verify that the distributor gear is installed correctly - it should be set as stock. While you are at TDC, it is a quick check to verify that the cam timing is correct as well (although I doubt that is your problem if it ran fine before and nothing mechanical was changed).

 

If the distributor timing gear is installed correctly per factory manual, I'd center the distributor hold down bolt in the adjusting slot, lock it there and focus on getting your Tooth #1 Angle correct. (Mine is set to 229.3). You do not need to turn the distributor to set the timing. The software will figure out where the engine is and fire the coil at the correct time. You just need to make sure the rotor is pointing in the right direction.

 

When setting the timing, make sure to switch the fixed advance setting from use table to use fixed timing. I like to set it at 15 deg when setting the Tooth #1 Angle. (make sure trigger angle/offset is set to 0)

It really helps to use an advance timing light.

 

Why are you doubling the VE and halving the req fuel?

MS3 has plenty of resolution - in my experience, this should not be necessary.

 

Sam

[SleeperZ]

Just a thought with the idle control. If it's running too rich (it is, about 11:1 at 1000-1100 rpm) perhaps that it why it won't tolerate a closed throttle. If I can get the fuel map more correct, maybe I'll be able to close the throttle, I have no experience with speed-density EFI.

 

Another piece of data in that regard is I have no vacuum at idle rpms. I can hold the throttle at 20%, keeping the RPM at about 1000, and there is very little vacuum. I do have a performance cam shaft somewhat similar to the Schneider, but it would produce 10" of vacuum at idle. I wanted to get it to idle first before I struggle with that though.

 

Regarding the cam setup, I have verified timing on it so many times I get cross-eyed. It is set to the number 2 position and is timed perfectly, and that is the recommendation from the grinder. I did originally set it to the number 3 position because I wanted to run a lower powerband, but I changed it to the recommendation just because I want a known baseline first.

 

Now the distributor setup is really throwing me for a loop. It is absolutely set to the factory position. However, with TDC set (new PF damper, new timing marker) and the distributor body advanced all the way, the rotor is centered at the number one tower, and I feel it should be at the leading edge. So that is why I am seriously considering dropping the oil pump to get another tooth and have a better advance range. Of course I am going to verify actual TDC with the new damper and pointer, and check the distributor position before making the change.

 

Thanks for the step by step Sam. I don't know why this is so confusing to me. And you are correct in wondering about the doubled VE table, but that is because it came from Zmanco's MS-2 table. I am sure you are right and I don't need the resolution. We'll see where that goes.

[Zmanco]

I'm running MS2/extra which only supports integer values for the VE table hence the need to double the VE values and halve req fuel to get more range for tuning idle. I believe MS3 supports decimal values for VE? Then you could go back to the "proper" req fuel and halve the VE table.

 

Just last week I had the head milled to clean up the surface and after reassembling it, it would not start unless I floored the throttle to go into flood mode. Turned out I had moved the cam to remove the followers and when I put the cam gear back on (also not running on the #1 position) I failed to verify that I wasn't a tooth off. The engine exhibed the same symptoms as you describe. Turns out it was 2 teeth retarded. To be sure, put the cam gear on in #1 postion and verify that the wedge on the cam gear lines up with the mark on the cam tower. Then move the cam a few deg to put it on the hole you want. If you didn't already verify that, I'd suggest doing it just to be sure. Alternatively, take it for a quick drive - if there is less torque than before you started this project, that's another clue

Edited September 5, 2012 by Zmanco

[Sam280Z]

I can think of no reason to have to install the distributor driveshaft one tooth off.

I would verify the timing mark on your damper. Put a drinking straw in the #1 sparkplug hole and turn the motor by hand until the straw is at its max height and the #1 cyl cam lobes are pointing up (valves closed).

 

Is this the damper you have: http://www.summitracing.com/parts/PFS-80055/?rtype=10?

Part number 80055?

 

That damper is for many applications (L16, L18, L20B, L24, L26, & L28). The timing pointers may differ on these engines.

 

Ignition advance has a HUGE effect on vacuum.

 

Sam

[SleeperZ]

I can think of no reason to have to install the distributor driveshaft one tooth off.

I would verify the timing mark on your damper. Put a drinking straw in the #1 sparkplug hole and turn the motor by hand until the straw is at its max height and the #1 cyl cam lobes are pointing up (valves closed).

 

Is this the damper you have: http://www.summitracing.com/parts/PFS-80055/?rtype=10?

Part number 80055?

 

That damper is for many applications (L16, L18, L20B, L24, L26, & L28). The timing pointers may differ on these engines.

 

Ignition advance has a HUGE effect on vacuum.

 

Sam

Yes, that is the damper. I had to dig out a timing pointer for an L28, and it is very difficult to see and line up as it is very low on the right side of the engine. I really liked where the L28ET pointer was, higher on the left, you could rotate the distributor and watch the mark at the same time. Now I have intercooler piping and oil cooler lines in the way. I am going to find TDC and lower a pointer tip right to the damper TDC mark so at least I know where that one reference is.

[SleeperZ]

Well, halfway there.

 

I found TDC, and it is off a bit. My cam timing should still be good because I set that with the degree wheel and a piston stop, but I need to check that again. But when I set the crank at TDC, the distributor tang was straight up and down. I moved it back a tooth, and now the rotor is where it should be, just past number one spark terminal.

 

I don't have any more time tonight to fire it up and get the logs so I can the MS referenced, and get the VE tables right.

[SleeperZ]

So now I've really stepped in it. I checked the cam timing and it was retarded by the width of the cam tower notch on cam gear position 2. I put in the wedge and advanced the chain one gear tooth, and my wedge wasn't secure enough and it popped out. So now my tensioner is mislocated. Never did this before, first time for everything. Looks like I get to remove my radiator, alternator, damper, and front cover to put this thing back together. Bright side, I'll know it's all lined up, and hopefully I can still get it all together so I can drag it to the track for tuning.

 

No time to street tune it before Saturday I'm sure, but at least you folks will be there to help me out.

 

 

Yes?....

[Zmanco]

Well, that's good news and bad news - good news that you probably have found the problem, bad news that you have to r&r the timing cover.

 

FYI, you'll likely need to replace the timing cover gasket. I have a spare set if you can't get one in time, although I know Castle Rock isn't all that close to you.

 

Also, I'd suggest using some form a gasket on the timing cover gasket - for some reason I had coolant leaks on my turbo motor when I installed the gaskets dry that I finally cured with this.

 

 

Get it running and come out to the track and we'll help you get it tuned. Maybe we can convince Roy to let you go out in multiple sessions in the morning so you can get it sorted faster. BTW, run VE Analyzer from Tuner Studio on the drive out and vary your engine speed and load a lot and you'll be surprise how much progress you'll make even before you get on the track.

 

Lastly, for VEAL to work well, you need to set the Lambda Delay. Attached is what I've found to work well. In my case, the O2 sensor is mounted on the underside of the down tube about 1 foot from the exit of the turbo. If yours is farther than that that, these times may be too short.

Lambda_delay_2012-09-06_09.36.40.table.zip

[SleeperZ]

I was planning to tow it out, it's just too far to rely on the Z to hold together, not that I anticipate a breakdown.

 

I appreciate the offer of a front cover gasket, I might need it, hopefully not. I have used that very gasket compound for years, it works really well. I used it on my front cover years ago, and it's still dry. If the gasket holds together on removal, I'll just goo it up again. The only thing I dread is re-installing the damper, that thing is a PITA. I had the advantage of first installing it this past February when the garage was 20F and the damper was 150F.

 

I will look into that delay table. I put my O2 sensor way downstream, it's actually mounted in the tranny tunnel past the end of my downpipe, near the shifter. I routed the cable up through the shifter hole.

 

Hopefully I'll see you Saturday.

[Zmanco]

One more thing I just though of: make sure you have Incorporate AFR Target set to "include" as that's how I tuned. This enables changing AFR targets later without having to retune VE. FYI, the VE values will be different with this turned on so you can't switch back and forth without retuning.

 

Lastly, I've changed my strategy for timing and AFR a little so here's my latest set of tables if you want to start from these. I've pulled some timing under boost near the torque peak to reduce detonation, and also reduced advance under light throttle at low rpm to improve driveability. I also went to richer AFR targets there as I was getting mild surging.

tables.zip

[Bernardd]

I've gotten the chain back on without taking everything apart. Try it before ripping everything apart. (I've done that too). I used a led light to see what was going and a long screw driver on the tensioner while a buddy kept the chain tight. Give it a shot.

[SleeperZ]

I've gotten the chain back on without taking everything apart. Try it before ripping everything apart. (I've done that too). I used a led light to see what was going and a long screw driver on the tensioner while a buddy kept the chain tight. Give it a shot.

I might give it a try. I can't remember what that thing looks like, whether there is a spring that could get crunched if I can pull that tensioner back....

[SleeperZ]

Pulled the front of the engine apart. Getting the damper off was tough, had to use my puller attached to my electric impact, with a hardened washer to protect the crank threads. I was afraid it would strip the puller threads.

 

Now the cam is timed right, I have to still re-assemble this thing tonight. The front cover gasket is still in one piece although some of the oil pan gasket separated with the cover. Hopefully that will seal; the form-a-gasket will not fill very well, and silicone could break off and plug the oil pickup.

[Sam280Z]

Sleeper,

For future reference, the crankshaft bolt is center drilled to accept a puller and the head is smaller than than the crankshaft snout diameter which allows the pulley to be pulled over it. Just screw the crankshaft bolt in and use the puller - no washer needed.

 

sam

[SleeperZ]

Sleeper,

For future reference, the crankshaft bolt is center drilled to accept a puller and the head is smaller than than the crankshaft snout diameter which allows the pulley to be pulled over it. Just screw the crankshaft bolt in and use the puller - no washer needed.

 

sam

My crank bolt is enormous, takes a 35mm socket. I couldn't seem to find a stock one when I needed it, but yours is the same suggestion Jeff Winter had when I mentioned my struggles at the track Saturday.

 

BTW, Zmanco helped out a lot, and it seems as though the MS-3 is working great, but the engine is just not acting right. It had no vacuum, and would not idle as a result. I checked ignition timing, dead on and stable. I checked cam timing, dead on in stock cam gear position #2, just as the grinder recommends.

 

I did end up advancing the cam one cam gear tooth, and it improved slightly, almost idles, about 2" Hg vacuum where my old Schneider grind would idle at 10". I am going to go over the two cam cards and see if I missed something, maybe advance the cam one more tooth just for "fun", and if I can't get anywhere I guess I'll go back to a factory stock cam that is known to be good. Gotta get this thing rolling !!

[SleeperZ]

I think I am past the mechanical issues now. Took it out for a spin, and it needs some tuning work for sure.

 

It does idle now, timing on 20 BTDC, cam dialed in according to the card, but still very low vacuum. I did a warm dry compression test and it's quite low but even. I got 85-90 across all cylinders where typically I get about 110-115 psi on a stock L28ET at this elevation. I attribute the low compression to the camshaft, I suspect it is not well suited to the low compression turbo engine although it has next to no overlap at 0.050" valve lift.

 

It hesitates and misfires under light load. Of course my plugs are completely sooty, maybe I'm starting to foul them. I posted my configuration and datalog on the MS3 forums --

 

http://msextra.com/forums/viewtopic.php?f=131&t=46951

 

I'd appreciate any insights, I'm still on a huge learning curve with this.

[Zmanco]

I wouldn't be too concerned yet about the low compression readings as you could probably increase them by doing the test warm, holding the throttle open, adding a little oil to the cylinders, etc. What's the MAP reading at idle? Mine is typically between 45 and 48 at 750 rpm at 6200 ft elevation.

 

As for hesitating and misfires, your new best friend is datalogging. Look at the misfire events to see what's going on. One simple cause could be not enough Accel Enrichment. There's really no good way to tune this except trial and error, although I think I saw an article on the DIY Autotune site that was the best approach I've seen yet. Most people use too much AE initially as it's an easy way to solve hesitation issues due to improperly tuned VE tables. I have learned that as I improve the VE table, I find I can use less and less AE. So either use it sparingly to start, or don't forget to come back and reduce it later.

[SleeperZ]

I posted a composite tooth log on MSExtra. Looks like my intermittent in the tach wiring is still there, as I lost sync over 100 times in a 4 minute drive. WTH!?!?! Time to strip out the #$%^@ tach wiring and re-do it.

[Zmanco]

How did you wire it? Did you use shielded wire? At which end is it grounded? FYI, I know my setup is different than yours (using EDIS with trigger off of crank), but I used shielded wire grounded at MS and have no issues with tach sync. Try to avoid routing it near the injector wires too - but you probably already knew that.

[SleeperZ]

I used shielded wire grounded at MS. I wired the 1k ohm pullup resistor to 12V at the distributor connector, just the missing tooth part, left the cam position output open. When I was first troubleshooting this issue, I found a bad ground wire in the factory wiring at the optical sensor, so I replaced just that section of harness with some twisted wires and spade terminals. I will wire a new harness right up to that now, and run it straight back to the MS. I don't know how much better it will be, I hope I don't have a bad optical module, those are crazy expensive.