Time attack beetle

[Humble]

I finally had some good luck with Lucy. I swapped out the BMD pulley kit for a different sand seal setup and found that I hadn't machined the back face of the crank pulley enough so it cut the sand seal rendering it useless. No wonder it was pissing oil! New seal, new pulley, and everything seems dry. Underneath the motor, the oil relief plug was leaking under high oil pressure (anything over 30psi really) so I pulled it and changed the compression washer. After warming up the motor I loaded the engine up using the brakes (don't do this kids) to build some boost and managed 12 psi at about 6000 rpm. Shut everything down and checked for leaks, only to find that the crank was dry! The relief plug has a very small drip (one or two a minute) under high rpms but other wise everything else is dry.

During the first warmup I had some crazy lean spikes that would kill the motor after cold start. I've been slowly working on my cold start enrichment to perfect it and getting a little closer every day. I've also been working on the fuel map to work out super lean areas when cracking the throttle. Slowly but surely she's coming along, and another dyno day is in the future.

I have a NASA track day weekend coming up at the end of August at Thunderhill which I would love to take the bug to but I might run out of time.

Video forth coming...

[Humble]

Here's the video as promised. She's still running a bit rough with a mean lean spike whenever I touch the gas from idle. Seems better above 3000 rpms but still leans out a bit. The throttle response is very slow too and I'm trying to work that out. Going to schedule a dyno day next week and hopefully she'll be ready ready in August!

http://www.youtube.com/watch?v=SC0n2zEMikU

[NO_H2O]

put it in flat black primer and roll it.

[Humble]

Got her running again with a couple updates. Updated tuner studio and went back to an earlier tune. Also swapped out the dead LC-1 for a new one, and changed the O2 sensor just in case. I installed a new ground on the oil tank so maybe the oil temp gauge would read correctly, and rerouted the 1-2 cylinder head temp wire for the same reason. Once she was running I reset the mechanical timing which solved a lot of the starting problems.

I took her for a short spin down the hill and had a cloud following me back up. The sand seal didn't do anything for the oil leak and it just poured oil as soon as I hit 2-4psi boost. These oil leaks are killing me :P

[NO_H2O]

Do you have a good size breather system?

[Humble]

I'm running 1/2" lines on each valve cover and the oil filler neck. There's also a 1" vent/filter on the top of the oil tank as well.

I know the dry sump pump isn't strong enough to pull a vacuum but it seems like there is excessive crank case pressure to me. I thought it might be that the rings haven't seated yet as there is only 2 hours of dyno time on this motor, but it should be dry from the get go.

[Wally]

Originally Posted by Humble

I know the dry sump pump isn't strong enough to pull a vacuum but it seems like there is excessive crank case pressure to me. I thought it might be that the rings haven't seated yet as there is only 2 hours of dyno time on this motor, but it should be dry from the get go.

I agree. Still my rings only seemed to have seated this season as I now have 1 full bar more cylinder pressure on cranking. Maybe not the best comparison, but just saying yours rings not really seating yet would be my best bet as well with just 2 hours run time.
And still, just a few psi boost should be possible without leaking on seals that badly..
Keep the spirit! even though this is frustrating as h*ll.

[kuleinc]

Any updates?

[Humble]

weather and side jobs have kept me from working on the bug unfortunately, but hopefully that will turn around in the next week or so. I have a little bit of cash and I'd like to get the car back to the dyno.

[chug_A_bug]

sounds really mean man... nice work hope to see it on the track With some video

Chris.

[NO_H2O]

You will get it ironed out. Then we need some in-car video.

[AIRSICK]

Hey, that's great. Always nice to make progress.

[Humble]

It's about time....

I had an epiphany last week regarding timing on the race car and finally had a chance to check it out last night. Sure enough the timing was way, way out. A quick and easy correction, a little tune up, and I hit the road.

http://vimeo.com/14062651

btw, if you can see it, 12 o'clock on the speedo is 80mph and it is calibrated

All I can say is holy sh*t! She's fast and only making about 10psi until I hit detonation from having way too much timing. She's also running pig rich but that's a little less of a problem. Seat of the pants dyno says 275-ish and there's still a lot on tap.

[chug_A_bug]

SWEET Driving Man.. that does look Scary fast lol
can't wait to see it on the track

Chris.

[Jim]

The car looks to handle very well and reving to fast!!!