Turbo ETA build

[Nebraska_e28]

Hell yeah! Nice progress.

[turbodan]

I may have found some injectors. Bosch 0 280 150 785, OE for some older Volvo 850's. About 30 lbs/hr. Doing more research, I found this gem:

https://www.youtube.com/watch?v=7oAamddPWjw

There are many different varieties of these injectors that all fit the bill on paper, just going by flow rate and impedance. It is more difficult to narrow these options down by spray pattern, which I would like to match to engine configuration. The M20 uses one intake valve per cylinder so I want an injector with a narrow cone shaped pattern. I believe the Saab injectors I have in there now are similar to the injectors BMW used on their 24v motors with a split double cone pattern, aimed at both intake valves. These are blasting right into the port walls in the M20. They seem to run well, nice idle especially, but the fuel map differs in some ways from the M30 injectors I just took out. Seems generally lean at moderate load and low RPM. I can't help but suppose that this is due to fuel pooling differently with the mismatched pattern.

I think I will order some of those -785's. I'm afraid to be disappointed again with all of the fuel injector bullshit I've been through with this project already. Trying to save a little money has resulted in swapping injectors five times and I'm still not there yet. At least it's not difficult on the M20, once you file a specific corner off of the valve cover where the intake manifold bracket bolts on. With a little additional clearance here, the whole rail sneaks right out.

[jacobthegoat]

I had the same problem with eBay vendors selling bad injectors, leaked in the same spot. Hell it could be the same injectors I bought a set out of a CJ Wrangler that ended up working perfect but it took two tries with different sellers.

Check their reviews on all items on their page and filter by negative reviews before buying and you’ll find a set.

That’s what worked for me. Goodluck

[turbodan]

The guy that sold me the 30lb set has 100% positive feedback. Not for long. Even if I get a full refund I'm still out another 12 bucks for the new pintle caps, not to mention the roughly 90 minutes it took to do the job twice. I don't understand why people sell garbage, unless they're hoping I just take the L and write it off.

There are a few places I can get these -785's from outside of ebay and I will definitely be doing that.

[turbodan]

It didn't take long for my best behavior to revert back to historical norms. Somebody in a Challenger f'ed around and found out. Also buried a very inconsiderate driver in a Lincoln. Kind of person that aggressively maneuvers to get in front of you while rolling up to a red light. No mercy for that sort of thing. Only swift retribution.

My 30lb injectors are supposed to get here Monday. Going to take a trip to the dyno and see what it's doing in the next couple weeks. It may be putting down 200 rear wheel if I were to venture a guess.

[slownrusty]

Very cool, sounds great as well!
Congrats.
Are you running the car on MS2?

[turbodan]

Yes, its running one of those MSPNP units from DIYAutotune.

[turbodan]

Going in now with these. Hopefully won't be back in there for a while. Bought from the place with an excellent website with tons of information about flow rates and impedance for all these different injectors.

I have a couple of these Saab injectors sitting here that are basically junk so I figured why not take one apart and see what's inside. I had come across a video showing a similar injector modified to increase the flow substantially, so I'm curious how that could be done.





Once the crimp on the bottom is rolled back, the pintle and nozzle can be removed. On this injector the flow can actually be increased by increasing the diameter of the nozzle where the pintle seats. Like larger valves in a cylinder head, a larger hole here will open a larger ring for the same lift and significantly increase flow.

All that said, I wouldn't quite be up for modifying a set of 6, putting them back together and trying them out. Seems like it would be unreliable to re-crimp the injector, it may or may not crack the second time. Enlarging the diameter of the nozzle also necessarily reduces the area of the seat on the other side which may increase wear or leakage. It would be an interesting experiment though.

[turbodan]

I can't believe this shit. Started the car up today and barely made it out of the driveway before it dropped a cylinder. Fuel injector on cylinder 5 tests at .8 megaohms between the pins. I can not catch a break with fuel injectors.

Yesterday I spent some time doing some street tuning with the wideband hooked up. Pulled a bunch more fuel out to get the AFR under boost just under 12:1. It feels strong and withstood quite a few second and third gear pulls with no trouble. The injector duty cycle is hitting 72 percent even with the mixture leaned out. I'm a little surprised by this. Assuming the usual BSFC it should be making around 230rwhp for that duty cycle. It is possible, boost is hitting 11-12 psi by that RPM. Need to get this thing on the dyno before I make any changes.

[turbodan]

I emailed Motorwest on Saturday and the said they would send out a replacement ASAP. On Monday I ordered another entire set of injectors from a different vendor. Today I received the package from Motorwest with my replacement. Of course, there was a mix up and I what I received was not correct. As of today I have not seen the other set of injectors or tracking information for the shipment. They may not have even shipped yet.

[tschultz]

Sorry for the troubles. I went with these 34lbers which can be had for about $25 each:

34#'s (@3bar) from some sort of 3.8L GM vehicle (L67 V8 supercharged)--Bosch#: 0280 155 811

[turbodan]

Motorwest overnighted the second shipment and paid extra for Saturday delivery. That's good stuff. The car is running great. Never seems smoother than when it was only running on 5 cylinders last time I drove it.

[turbodan]

https://youtube.com/shorts/MYsMlluzvng?feature=share

I've been trying to get a good recording of this exhaust note. It's got a particular lumpy, reverberating quality. Sounds like a helicopter flying at a distance. I dig it.

I ordered up a driveshaft the other day. The car has developed a vibration under boost, usually in second gear. Driveshaft in there now is probably original.

I also scored an M20B25 intake manifold so that's going on in the near future. I would like to dyno this thing as is but I don't know if that's going to happen in time.

[turbodan]

Never did make it to the dyno before I slapped the B25 intake on this morning. There is some interesting data to be found in the differences between the fuel maps for the M20B27 manifold and M20B25 manifold:



The slug of torque at 3k has moved up to 4k. The top end pull is greatly improved but without the B25 cam the power curve is still too brief. The boost creep has been mitigated, perhaps the additional top end airflow is maintaining a better balance between supply and demand. It still creeps up to 11 psi but it peaks around 4500 RPM and holds steady. The full B27 setup continued to creep until redline.

This might not be a bad setup with higher boost. It feels sedate until the boost ramps up around 4k. If it was spooling up to 11 psi at lower revs I suspect it would be producing a big fat tabletop of torque. My original dyno sheet shows something like this, although that was with a B25 cam. I don't see any way the milder ETA cam produces less torque though.

In other news, the rear main has begun to weep and I believe the valve seals are hardened and providing little restriction. When I pulled the intake I found a good amount of oil in the intake ports and going back up the runners, the plenum itself was bone dry. To my knowledge this is an unopened, original 1988 528e motor so this is to be expected.

With the new tune the injector duty cycle remains at about 73%, mathematically that should equate to about 230rwhp. That's exactly what the original build made at this boost level and RPM. I'm still going to do the cam though, I need the revs. It's pulling hard into the limiter, might as well finish the job here and go full 2.7i, open up the top end of the VE curve a bit and raise the rev limit to suit.

[turbodan]

Manual boost controller came in today. I was surprised that I couldn't find the one I used to run from last time. It's not like me to get rid of anything but that little device got lost along the way. I shopped around for one that looked like it came from a hardware store, almost considered trying to make my own. I think it would have actually cost more to go to Home Depot and buy the pieces. This one was $16 shipped. Hard to beat.

Boost was hitting 6 psi on spoolup and only climbing up to 12 psi over 4000 RPM. Might as well hit that 12 psi on spoolup and make a proper torque curve. This was $16 well spent. It's having trouble with traction in second gear, depending on the quality of the pavement it may or may not smoke the tires. So far the clutch is hanging in there, though if I remember correctly this is about the limit for the stock M20 clutch.

The turbo ETA is a pretty excellent setup, especially with the B25 intake manifold. Despite the mild cam, it's ripping all the way into the limiter. It could probably pull to at least 5500 but that would be exploring the limits of the single valve springs. The B27 cam has more lift and steeper opening and closing ramps than the 2.5 so it is more likely to float and drop valves than a B25 cam would be, even with the same springs.

I went ahead and sprung for a complete B25 head, that should be here tomorrow. Then I'll be back to the original 2007 configuration which I remembered so fondly. The car is running strong as is but I can't stop now. Next step would be either the GT2871R .86 or a GT3071R .82. The GT2871R is tried and true, it made excellent power and ran the fastest ET's of the four different iterations of the previous project. You could say it made the best, most usable power. The 3071R offers a little more flow through the turbine, which is always beneficial especially at higher boost. Then I'm trying to tell myself that I'm going to keep this project under control and not build it into a uselessly overpowered wheelspin machine.

[turbodan]

A second gear roll on. It's breaking the tires loose consistently in second gear now that the boost controller is in charge. By the time the throttle is fully open it's already making 5 psi. As you can see, approaching the party pooping wet blanket of a redline required by the single valve springs, duty cycle has not dropped off and it is still pulling quite well.

I just got the TPS properly wired in today. The stock wiring generates a signal but it is not clean or proportional to the throttle opening. It almost works for overrun fuel cut but not quite well enough. The wiring change is simple, two wires need to switch places. This was the correct wiring, which I very much wanted to verify before snapping these into the new connector housing:



Pin 1 according to the ETM is the Brown/Blue and pin 2 is supposed to be just Brown but actually had an orange stripe. Pin 3, the brown/black wire, stayed put. Now I have a reading of about 101 with the throttle closed and about 589 with the throttle wide open, with a linear progression through all points in between.

Funny story about the driveshaft. That vibration in second gear turned out to the the rear CV axle inner joint making contact with the exhaust system. Apparently the diff mount allows more movement than expected and the bolt heads were contacting the 3" pipe making it's way toward the back. I have a new diff mount that is waiting to be done in conjunction with new subframe mounts, better get my ass in gear and sort that rear end out. The diff is dropping a significant amount, this is not good.

The driveshaft that came out was old and probably doesn't have much life left in it, so I put the new unit in and took it for a test drive. Immediate sadness, I felt a new and significant shudder upon accelerating through 20mph. Some degree of roughness was present at all speeds, and I'm wondering if it was always like that or if the $600 shaft I received from Driveline Services of Portland is a total piece of shit. I checked and rechecked the CSB preload, it was fine and the problem persisted. An email was sent but I never got a response. I pulled the driveshaft back out and checked the center u-joint with a dial indicator I had conveniently purchased at a garage sale just days before. The center joint exhibits .005" rotational play and .010" up and down play, the latter measurement indicating a problem that would allow misalignment along the axis of rotation and quite probably explaining my issue. With the stock driveshaft reinstalled, the car runs smooth as glass again. Now I get to call Driveline Services and try to get this $600 piece of shit sorted out. I dread this. I know they're going to fight with me about it and refuse to pay return shipping.

I've used their stuff before and it's been great. This shaft was built by PTI, who makes the Dorman driveshafts, and I've had good luck with their stuff too. This one is a piece of shit though. I just want send it back, order a BMW driveshaft, and be fucking done with it.

[turbodan]

Updates if anyone is even still reading this.

I inquired about a BMW driveshaft, which is still available although I was told it is six weeks out from Germany. I decided to give driveline services and PTI another chance. They sent a return label for the first abomination of a driveshaft and started building another one for me. Driveshaft number two arrived on Saturday and I was appalled by what I received. The rear joint had one axis that was very stiff and did not feel smooth if you applied enough force to move it. I found some circlips smashed into their grooves with excessive force, others not seated at all that popped out with a screwdriver and one fully seated in its groove but able to spin freely because it wasn't retaining shit. One circlip was installed backwards, flat side in and rounded side against the groove.

I'm not sure if this was incompetence or spite, but this driveshaft was fucked up worse than the first one. At least the first one appeared to have been built properly and the joints felt right. I decided to get out the hammer, the drift, the file and some good snap ring pliers and get work. Couldn't install it like this, didn't want to turn around and try to return it again. At this point I'm expecting serious doubt from driveline services that I'm not a ham fisted dickhead blaming their driveshafts for some other problem. So I filed some circlips, made adjustments with some precision hammer and drift action and got the apparent issues sorted out. With little confidence, I installed the driveshaft and was pleasantly surprised to find that it runs smooth as glass.

There are a few other places that offer driveshafts for these cars. Driveline Services can build you one but they will be more expensive than these other shops if they do it in house. Their basic replacement shaft is sublet out to PTI, which does a really bad job at building driveshafts. Maybe the first one was a fluke and the second one was a middle finger, who knows. Maybe things like this only happen to me. At least the car is running strong. Hanging in there at 12/13 psi with no clutch or head gasket trouble. I don't think I need more boost at the moment, but I am looking forward to getting this other head built with dual valve springs and a proper camshaft to broaden the power curve and raise that rev limit up.

[Nebraska_e28]

Glad to hear you were able to salvage things! Any video footage?

[turbodan]

https://youtu.be/KfwAI3kS_cs

Here's a quickie. Closer to sea level, this would equal about 9 psi. It's 12 up here but that first three is just getting back up to 100 kpa. Manifold pressure peaks around 160 kpa where it's set right now.

[Galahad]

That's a whole lot faster than my eta ever was, looking good

[turbodan]

I think it's pretty comparable to an S50/S52 at this boost level in terms of outright acceleration.

[Eta power]

It makes me so happy to see turbodan still doing turbo things. Someday maybe my car can be less slow, too. Great thread.

[turbodan]

It feels right to be back at it again. Should have never left.

One of the only videos from the old car is this one:

https://youtu.be/GRAXDxRrofA

Unfortunately it's not even a solid pull. If the title is correct it was having issues with spark. This is increasingly likely at higher boost levels. You can see how it's just starting to spool up and stomp ass though. Car was nasty.

[Eta power]

Oh, that reminds me!

https://www.youtube.com/watch?v=92bwAMLhSKo

Went digging in my old youtube account and found this video. It's your old car, right? I must have watched this video 100 times over the years

[turbodan]

Indeed it was. I believe that was with the GT2871R at about 16 psi. Ran a 13.0 in the 1/4 at 108 mph. That was a pretty good place to be.