wvumtnbkr said:That's what I figured. Is there a way to push oil into the return hole and see if it comes out where it's supposed to?
The "blockage" would need to be between the sensor and the crank. Otherwise, you would have indicated low pressure.
Yea that's a good idea. I have a hand pump I'll try to force oil through. Going to pull the main bearings and crank tonight.
My vote is that the narrowest oil passages are blocked with chunks of timing chain guides.
rozap said:Steve did tell me that the alternator fan machined itself off and sent shrapnel through the hood, narrowly missing a fuel line.
Excellent visual with the description. I hope to never have the opportunity to use that but if the need arises...
Isn't the oil filter between the pump and the rest of the engine? Is the filter full of chit too?
Well, the mystery of the previous motor is solved and it's embarrassing. Oil lines were hooked up backwards. So it tried to push oil through the filter the wrong way which didn't happen because of the drainback valve. The oil pressure sensor was upstream of this so it showed oil pressure. I should've trusted my ears more. I'm an idiot and that was an expensive mistake.
Picked up a new used engine on Whidbey island a few days ago for $350 and also a transmission. Checked it over and threw it in the car over the weekend. It is running well but now I have oiling system anxiety, every tick or rattle freaks me out.
The car hauls ass though, and it sounds incredible. Tons of torque. Throttle response is fantastic. But lots of tuning to do still. There's also a fuel starvation issue so I ordered some walbro mp-12 pucks for the cell.
In reply to rozap :
Just get a cheap fuel surge tank and another pump.
Solves the issue 100% and you never need to mess with it.
In reply to rozap :
So happy to see the quick turn around on getting it running again. That drivetrain is fun in my wife's Passat so I imagine it must be a rocket in an X/19! I love this project and can't wait to see race photos
We are signed up for the race at The Ridge in Shelton, WA on 4/26. I've been sorting out a bunch of little things on the car. The rules said we need an engine cover and I attempted to make one out of fiberglass. Big mistake. Messy, stinky, gross, time consuming, and the part was garbage. Never again.
So the race is in a little less than two weeks and I had a scrap piece of aluminum in the shop, and nobody locally carries aluminum sheet. Dimensions are entirely defined by what scraps I had available. But, it's mostly done now, satisfies the rules I think, and I can see out the back (we also have a camera with a ~120 degree field of view, which helps visibility a ton) so it's Good Enough™.
re: the walbro pucks in the previous post - surge tank and an in tank pump would've been good in hindsight but the amount of time we have before the next race won't allow it. the walbro pucks seem to be working now, driving the car around and I haven't experienced the starvation that it was doing before, but we won't really know until we get it on track. worst case scenario is that we learn that we only get some fraction out of the tank before the end of a stint, which is fine. this next race is going to be entirely a learning experience. I fully expect that tons of things will go wrong and we'll finish lower down than we were finishing with the original Fiat drivetrain, but over time hopefully we can make the car more competitive.
scrap metal engine cover
And a few little things that I happened to take pictures of. Windows and Radios.
Car is mostly ready. Sorted out the dash display and telemetry this weekend. Teammate did a great job cramming everything into the little box. There's a LoRa wireless module that streams data back to the pits which I figured we'd put elsewhere, but she managed to fit the stm32, display, shift light driver and Lora module into a neat little package.
Hopefully we don't blow the car up on the test day. Still have some VE map tuning to do.
I like the louvers!
rozap said:Well, the mystery of the previous motor is solved and it's embarrassing. Oil lines were hooked up backwards. So it tried to push oil through the filter the wrong way which didn't happen because of the drainback valve. The oil pressure sensor was upstream of this so it showed oil pressure. I should've trusted my ears more. I'm an idiot and that was an expensive mistake.
My friend had this happen to the $10k+ built 5sgte for his aw11. It was caught on the first startup but the damage had already been done. They fixed the oil lines and it started up fine, but the grenaded the engine on the first drive.
We are back from the race at the ridge this weekend. It rained the whole time, everywhere between a light drizzle and total downpour. We had fairly modest expectations going into the race and greatly exceeded all of them. Aside from some minor issues, the car ran great all weekend. It had loads of power.
The Friday test day we did a few short sessions with the laptop in the car running the tunerstudio auto tune program to dial in the VE table. We made some improvements here, but we lost a session due to someone oiling down the track. We eventually ran out of time and squeezed in a few laps during the final session and got a data log, and continued to adjust the tune from there. We made some improvements but drivability was still not quite right. Coming back on throttle the car would hesitate a bit, and then all of a sudden you'd get a load of torque, which, given the wet conditions required a lot of care on the fun pedal. Also the ECU randomly cut out once, which was a problem we couldn't reproduce, but it was the most concerning issue we found...
Saturday I went out. After a long red flag due to a BMW stuffing it in the wall on lap 1, I finally got a chance to push the car a bit. The car was running great but we were on the wrong tires for the conditions, so I had almost no grip. I had a few moments but the car is super forgiving. I got really sideways on a corner exit, corrected it, and was expecting a tank slapper and it just never happened. Every single time I made a correction the car responded exactly like I would have wanted it to with no drama. It inspired a ton of confidence, even in the pouring rain.
During the second driver stint the car cut out entirely. The dash still worked but couldn't talk to the ECU, so we guessed that it was a ECU power issue. Within a few minutes we tracked it down to the ECU relay, which had melted (it was not a high quality part....new bosch ones are going in now). Though the fix only took a few minutes we lost a lot of time having to get towed in. The car ran great for the rest of the day. We had fuel pickup problems where the car would start sucking in air with about half a tank left, so the max stint length was about an hour and a half.
Sunday was more of the same weather, but we swapped tires during the night from the rs4s to some yokohamas that are garbage in the dry but very good in the wet. We had one short stop on Sunday where we had to fix a piece of bodywork that was falling off, but other than that we ran all day with no major problems.
So we have a big list of things to improve, but the general basis is really good. We didn't cause any weird handling characteristics with the extra power and moving weight around in the car, and the reliability was much better than we expected. It ran cool all weekend without a single hiccup or concerning noise. Really looking forward to getting it dialed in. Being able to pass people in the braking zones, corners, corner exits, and straights was a whole new thing. I took it really easy because of the wet but there's a lot of capability in the car now that will allow me to improve my driving.
Looking forward to the next race.
This looks insane in the best way. I love it!
Shoot I was down in Shelton Saturday and totally forgot about this. Will have to catch the next one.
How does it feel putting power down out of corners? That is a lot of torque for a car that size and WB and it's the opposite end of the spectrum from what I race.
In reply to buzzboy :
In the wet and with our rough tune it was a little tougher than it should have been. The accelerator enrichment isn't dialed in yet so it wasn't as linear as it should be. But it wasn't undrivable or scary, just took a bit of patience. It was a lot of fun.
Also I realized that we forgot to adjust the accelerator pedal and could only get 88% throttle. And I had set the rev limiter to be 1k lower than the real redline for longevity. So those items plus our rough tune, there's some more in it.
Another driver came over to our paddock on Saturday night and told me I had a great save on an off camber corner exit when the car was sideways. There were a couple like that, but from where I was sitting, I never felt like it was in "great save" territory - the amount of weight and the way the car is set up it really felt easy to drive. Maybe it looked more dramatic from outside the car :)
Oh, and a team brought a set of scales to the race. The car weighs 2145, with a 43% front a 57% rear bias. That's like 40 pounds less than what a stock X1/9 weighs, with a slightly more neutral weight bias, stock is 41% front 59% rear. We also put the OEM bumpers back on this race because of our concerns about crashiness in the bad weather.
Here's a lap. We don't really have any overlaid telemetry, maybe next race.
Welp, we are back from our 7th race, and we got our first DNF and we won the I got screwed award.
We blew the head gasket on the test day, and stayed up until 3am fixing it. We took the race start on Saturday, and then I saw blue smoke out of the exhaust on deceleration. Shortly after, the dipstick shot out and oiled up the rear window right by the track exit, so I came into the pits. There was oil everywhere so we suspected massive blowby pushed it out. A compression test yielded 30-60-50-60-160-80 PSI across the cylinders. So we started tearing it down and found several roasted pistons. We rebuilt the bottom end of the engine on Saturday. We harvested some good pistons out of a VR6 core that I had and put new rings and bearings in it. We gave it a very light hone, as the cylinder bores still looked ok, certainly better than the bores of the Fiat 1500 that we ran several races on. We went out on Sunday morning and after several laps, the head gasket let go again. At that point we didn't have any more time to continue fixing stuff so we had to call it.
My best guess is that fuel starvation issues in the previous race started the process of roasting the pistons. We're going to switch to a holley mat pickup. We're also going to add some EGT sensors to monitor combustion temperature. In this race and the previous one, the engine coolant never exceeded 200, oil never exceed 210, so I think we have so much extra cooling capacity that we didn't see the elevated temperatures show up in the oil or coolant sensors. We're also going to rebuild the engine and go to all races in the future with a spare, though I may need to make modifications to the strut bar to allow the engine to come out the top versus the bottom, so we can change it at the track.
It was definitely a bummer to not get many laps, but everyone on the team stayed incredibly positive throughout the race. Nobody even suggested giving up until the very end. Tons of people came through our paddock to offer help and support as we did a marathon of wrenching over two days, and we made quite a few new friends. The people that attend lemons races are consistently some of the nicest and generous people I've ever met.
We've definitely learned more from this race than in any of the previous ones.
rozap said:We won the I got screwed award.
Was that one of the melted pistons or the trophy?
Glad to hear you all stayed positive about the whole thing.
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