Aftermarket LS Oil pan?

[n8thenetninja]

It's already at the machine shop, so it's a little late for that. The machinist seems to know his stuff. We'll see how it turns out.

[Monza Harry]

I would go to a welder and have pan heated and straightened as I described then if still needed I would consider having flange milled. The way it is you are going to have to mill the flange too much to get it flat. Clearancing the sump can be done by you with a grinder. Header probably has to be clearanced too.

It's already at the machine shop, so it's a little late for that. The machinist seems to know his stuff. We'll see how it turns out.

N8 I hope this guy does know what to do, By what I seen in your earlier photo's Monzaaddict's approach seems a better choice, my other thought would be to add another layer to the block/pan flange area then mill, this will add more weld stress to the program so better go back to MA's approach you will have a very thin flange after milling without addressing the twist. Either way stress relieving [heat up to just below critical temp and cool real slowly, Hell even putting it your BBQ and giving it a few heat/cool cycles would probably remove some twist, better if it was gradually torqued down to a flat reference plate] that pan would help with your situation better long term. As to your dropping Oil Pressure problem with the pan removed check that the oil level isn't being foamed up with the crank/rods. That situation sounds like either the oil is filled to high or it isn't making it's way back to the pan. If this happens again stop pull the breather on the valve cover [if your has one] and pull the dip stick and see whats up, valve cover full or foamy dip stick to help diagnose your situation. Harry

[monzaaddict]

I was just looking at f body ls1 oil pans and the spectra premium gmp 77a pan they now sell is no longer the gm casting but the china made casting that everyone else sells. The casting is actually smoother than the gm casting ( It looked like the molds were pretty worn on the ones I bought a few years ago hence the dremel marks all over the them when I did the powerbyace mod. There may still be some old stock around but they have definitely switch to a china sourced pan.

[monzaaddict]

Did they fix the pan?

[n8thenetninja]

The machinist did a really good job surfacing the pan. It's probably flatter than a stock one now. The only thing I had to do to make it fit was grind a little where the front of the pickup tube goes, and I hogged out the bolt holes a little bit more so it slipped on easier. Installed it with (yet another) new gasket and a little RTV (because why not at this point?). Sealed up as flat as can be. My oil pressure also came back with the pickup tube that actually goes far enough into the pump to seal.





Unfortunately, when I got it all back together and took it for a drive, there was still smoke coming off the headers, and it left a puddle in the garage when I came back.

So, after about 3 fingers of good scotch, I found the link to the rear cover with the rear main seal pre-installed that I used:
https://www.summitracing.com/parts/sum-g2621/reviews

If you scroll down a little, you find this review from February (long after I already purchased mine):


So, I decided I'd better pull the transmission (no, not the same day).

This is what I found when I got the transmission out:


It fell on the floor as soon as I moved the cover. The only thing holding that there was the flex plate. Wonderful part Pioneer...

To not take any chances, I got a Chevrolet Performance replacement cover, knocked out the seal that came pre-installed so I could use one of those silly alignment tools to get the cover perfect before tapping a new felpro seal in. I've seen videos of nice aluminum alignment tools that fit perfectly and get the job done fast. I had a plastic tool that I got from Jegs a while back, but never used because the seal was already installed in the cover. That stupid thing was too big to fit in between the cover and the crank, and I had to tap it with a mallet to get it in there. After that process I installed the new seal, and it was very obviously not aligned properly, but had the bottom of the seal pushed up to the crank. So I loosened the cover again, tightened the two pan bolts, then torqued the rear cover. Then I could see the seal was misaligned the other way with the top of the seal pushed on the top of the crank. At this point I figured as long as the surface of the pan and the cover are close enough to seal, the rear main seal should be able to center itself with loose bolts. I had already put a bead of RTV along the rear of the pan when I put the cover up. I loosened everything again, made sure the seal was centered as best I could by eyeballing it, torqued the rear cover bolts, then torqued the pan bolts.

Got it all reassembled at 1:00am the morning of the final points race of the season (for one category), took it for a test drive when the sun came up, and...

NO LEAKS!!!

So I ran it in the bonus race before the points race, and in the third round, this happened:


I'll post more about that in the suspension forum...

P.S. If you're wondering if it was the rear main the while time, that is of course possible. However, this is why I think it was leaking from both locations:
The oil leak was manageable for a while, so I dealt with it. That's probably when the pan was leaking. It was most definitely warped as the pictures show. It got way worse all of a sudden, and that's when I started taking things apart again. The point where it got so bad I couldn't ignore it anymore was probably when the rear main seal came out. Unfortunately we'll never know for sure.

[Monza Harry]

Ugly fight there Nate! But looks like that last right cross won the fight [for now]! Harry