Found the oil leak yesterday, I had assumed it was something simple like an oil supply/return line or the oil pressure sensor, but of course I couldn't be so lucky. Short of leaking through a hole in the side of the block I think it's about the worst possible place it could be. The stupid rear main made it about 100 miles and started peeing everywhere. Looks like the tranny is coming back out, for the 273483587th time. I hate this car.
Man, I feel you. I've got a front main leak and I just got this thing back together. Oh, and my wbo2 failed yesterday when doing some fine tuning. My motor also has some oil on the underside of the trans and it was clean as hell when i put it together.. What does your rear main leak look like, enough to drip on the ground?
What front/rear main seals did you use? I'm going OEM this time.
When you install the new one, wipe a little wheel bearing grease around the area between the seal and the crank. The manual states to knock in the seal until about 2-3mm past flush, you can use the old seal as a driver.
While the trans is off see if the input shaft gasket needs replacing too.
I just used a Discount Auto rear main last time. It was the first one I've done so I'm sure I screwed it up somehow. The bottom of the motor actually looks pretty clean, from the tranny back it has oil splattered on it but no real sign of where the oil is coming from. Once I crank the car up it'll start dripping out of the hole in the tranny, just a drip every 10 seconds or so.
I was able to get the day off work tomorrow so I'm going to pull the tranny tomorrow and swap it out. A friend is coming over with FM's rear main installer tool so hopefully that'll do the job.
Could be the front input or rear output seal of the transmission too. The front is often ignored and blamed on the rear main seal. I put a new output seal in and couldn't believe how much less oil there was. My entire turret was previously covered in oil, no longer.
I pull the trans out and it was the rear main. I'd pushed it too far in when installing it. I didn't even look at the trans seal, probably should have but as you can tell, I try I rarely do anything right the first time. I got it back together and nothing is leaking.
I went out to a car meet last night. I'm still nervous beating on the car but I was anxious to get some kind of idea where it's at power wise. I'm still at 12psi and found a 99-04 Mustang GT that agreed to run my car. He kept insisting it was "just boltons" when I asked what was done to it. My friend took a video, we ended up going from 10-90 before I let off. He had about a car lead and was clearly pulling.
Disappointed to get beat up on so bad, I went back and talked to the guy a little more. It turned out he was on a 75 shot, which made me feel a good bit better. Still not impressive but losing to a ~325whp mustang made me feel a lot better than a ~250whp mustang.
My car is really dying out on the top end of the powerband. I logged a pull on virtual dyno so you can see how it drops off. (I guess I accidently cropped out the RPM's, but the vertical lines should be 1000's, so the pull let out at ~6500 to give you an idea of the painful curve I'm up against)
I've got several issues going on that need to be addressed that should help; need to pull fuel from VE map, add timing, finish porting intake manifold (the top half is like 80% done), and install a bigger intercooler. But I don't feel like any of those issues should be causing the drop I'm seeing and I keep stressing over my valve adjustment.
When I adjusted the valves I adjusted them to the loose side of tollerances assuming they may seat in a little bit and to avoid the risk of burning a valve. When I checked clearances they're still right where I set them. Do you think it would be better to go back and adjust them more to the tight side (= open longer)?
Any other things to check regarding power dropoff like that? It doesn't feel like spark blowout or anything. Plugs are new and my COPs haven't had any issues in the past at such conservative boost levels.
What psi are you running? I am confused as to why your overall numbers are so low with the setup you're running.
It's ~12psi. I know the power is off, which was kinda the point of the post. I really don't think it's that bad aside from falling on its face as revs climbed. There's definitely some power left in it though.
Originally Posted by miata2fast
Are you sure your cam timing is set properly? Could you post your timing tables?
Your valve adjustment would not have that kind of effect on your power band unless you created a gapping hole.
I'll double check the the cam timing, but pretty sure it's right. I know the timing is backed way down, but the MSQ is on my computer at home. I'll add some back in and see what happens.
Hopefully I get some decent weather this weekend and make some progress.
Now that I look at it again I realize that it really only seems low because of the drop off. Are you running just wastegate? The torque curve doesn't look like an EBC curve and there appears to be some boost creep at what appears to be ~4800rpms shortly before it drops off.
Yeah, I'm running on the wastegate. Boost is pretty consistent though, wish I hadn't cropped it out now but it certainly wasn't enough to explain losing power like it did. It peaked, sagged a tiny bit, then climbed back up so at 6000+ it was at 12psi.
Low compression definitely has something to do with it, imo. Did you quadruple check base timing? Did you rev it when it was set to 10 static to make sure there is no latency? What is your timing map? Do you have some logs from the pulls?
I know I've got stuff to take care of, was just more curious if the valve adjustments would be causing part of my issue. I've been super paranoid about everything with this nightmare of a car. I'll mess with the tune and see if we can do a mo bettah one over the long weekend. As soon as I feel like it's running right I'll start throwing more boost at it.