10k RPM – 1991 Diamantschwarz 318is Slicktop – 231hp NA M42

[digger]

Not sure, as tuner said what I was seeing on the dyno screen wasn't accurate. But, it was posting 173 on the dyno end. When I asked, saying that was low, he said its 260 crank currently, with some room left. This isnt my specialty, though.

not sure where you are located but when tuning is 100% done be sure to find a dynojet to see what it makes as that is the gold standard reference

[chriso]

not sure where you are located but when tuning is 100% done be sure to find a dynojet to see what it makes as that is the gold standard reference

It's being tuned on a Mainline ProHub right now.

[chriso]

Upon further inspection, we believe we blew the throw out bearing. Ordered a new one just in case, and pulling the transmission likely this weekend. Tune should be good to go, but once we solve the transmission issue we’ll do an official dyno sheet with the machine calibrated.

Currently, the car is unable to shift while it’s running, and starting it while in gear will make the car move even if the clutch is fully pressed, so the clutch is not fully disengaging.

Hoping we’re just looking at a throw out bearing issue, but replacing master and slave cylinders, and removing the chase bays line that I used for some reason.

[chriso]

Upon further inspection, we believe we blew the throw out bearing. Ordered a new one just in case, and pulling the transmission likely this weekend. Tune should be good to go, but once we solve the transmission issue we’ll do an official dyno sheet with the machine calibrated.

Currently, the car is unable to shift while it’s running, and starting it while in gear will make the car move even if the clutch is fully pressed, so the clutch is not fully disengaging.

Hoping we’re just looking at a throw out bearing issue, but replacing master and slave cylinders, and removing the chase bays line that I used for some reason.

Jogged my memory on parts installed when I put the engine in.

I had replaced both master and slave cylinders, but I failed to replace the clutch release arm, pivot, spring, and throw out bearing.

Transmission is out this week, parts will be here Monday, so hoping this is the issue. Also doing input and output shaft bearing where were out.

With any luck, this will be all good to go in time for spring.

[chriso]

Update:

Transmission was good. No damage. The issue ended up being that hardware was too long and was making contact with the very center of the pressure plate and crankshaft. There’s very light scratches on both, but it was enough to prevent the clutch from fully engaging. We also discovered that the rear main seal had began leaking, so new hardware properly sized for the flywheel, and RMS are en route. Car is back on the dyno on Friday for the final run, and should be ready to go for when the salt is off the road in April.

This time around, we’re red loctiting, and metal marking bolt positions to ensure nothing is backing out.

We’re finally there.

[chriso]

Final issue: it appears that all of the transmission issues are leading back to the Bosch iBooster swap, and it boiling the brake fluid. I took the car out for a drive last Friday, and noticed the longer we ran, the worse the shifting got until it no longer would disengage the clutch.

This was happening at idle, and during driving whether the brakes were being used or not. Rather than troubleshooting, I am reverting it back to an e90 brake booster and putting the iBooster in the Vixen 21TD which needs a replacement for its ancient electric booster anyway, and will give me a bit of time to troubleshoot it and/or get the proper wiring harness which is now available from a few vendors for direct plug and play.

[eternal24k]

interesting, any idea how or why it could be boiling fluid? I was going to swap my X3 booster for an iBooster, this is the first i have heard of issues

[chriso]

interesting, any idea how or why it could be boiling fluid? I was going to swap my X3 booster for an iBooster, this is the first i have heard of issues

I’m honestly not knowledgeable enough here to be able to actually diagnose.

I originally swapped the iBooster into the car in 2019, I believe I was one of the first, after reading a basic write up on the EV DeLoreon forums. And even then, it was for an iBooster 1, and we wired it up with that information after finding a German wiring chart for the iBooster 2.

The E90 booster that was available locally fell through, so I instead ordered a pre-made iBooster 2 wiring harness with labeled pigtails, as originally we wired it directly the the iBooster pins, as the connector wasn’t available in 2019.

In addition, I don’t believe we’ve done a full brake fluid flush on the car, so that will be done at the same time. The car did sit undriven for 6 years, so who knows. Hoping this fixes the issue.

The other thought, is that it is related to a failing ABS module. I’d like to keep ABS, so I hope this isn’t the issue, and I really don’t want to pay to have it refurbished.