I just pulled my head off and got my pistons out. Here's the quick story. I was having low vacuum and some other issues, my mechanic does a leak down and tells me that he wants 2300 to put in new rings and bearings for the crank cause I'm leaking at the rings. he said the #4 was down to 25% and the others were like a little above 50%.
Here's the pics, tell me what you guys think. I obviously said fu to the mechanic and opted to do it myself and it's been a breeze so far. Gives me a chanc to upgrade some other stuff too with the money saved.





Hard to see but there's a little scoring on the side right where the flash relection is.


pic is blury but you can see the mark on the side better as the dark spot. The inside of the cylinders look great and no amrks or anything out of ordinary



Here's all 4 more or less. It's obvious I've been detonating. If anything it's been from running too rich rather than too lean. When I screwed it up I was doing a full throttle pass in 3rd at about 16 lbs and shifted to fourth. It emediatly hesitated and then I blew off a vacuum line from the ic and it was f-ed from there on. I was figuring piston rings from running too rich. What do you guys think? Are these still good if I clean them up a bit. The sides on them where the white or lighter spots are are a worn different from the rest of the piston, it's kinda rough textured. They have about 20k miles on them by the way.

If you need more pics let me know. All the bearings look fine that I've puled out so far. I haven't gotten the crank off yet.

I have some pretty good pics of my motor pull if anyone is interested-

check your links, i see broken image

shit, try this..

this is the site where they are hosted

http://community.webshots.com/user/xceler82
click on the eclipse one obviously not the mexico one, unless your curious about my study abroad experience!

study a broad? What was her name? LOL!

Anyways, I don't know about those pistons, at least the one looks like it's got some pretty mean grooves in the skirt. You really gotta be able to diagnose on your own as pics don't tell you everything, I usually judge this type of thing by feel and measurements. If nothing else, take them to your mechanic and ask him, unless you burned that bridge already. Also, be sure to mic the bearings and journals, or plasti-gage, or whatever your chosen method is, just looking at a bearing can only tell you so much, if you were detonating all the time it's posibble to hammer the bearings flat. If this were my engine, I'd probably clean the pistons up to really see what condition they're in, be careful if you try to scrape the carbon off because thats a good way to gouge the surfaces, then depending on that, I'd probably replace the ones that were scuffed up too bad, run a flex-hone through the cylinders, and buy some new bearings. Now the other thing you need to think about is, if the rings shattered and sent metal into the oil pan (that's what that scuffing looks like to me) then you're going to want to make sure there's no metal in the oil galleys/head/oil pump/etc. I'd steam clean the head cause it's off, pull apart the oil pump (can you rebuild ours?) and clean it up, and run a brush with soapy water through the oil passages (possible with our motor?) If you haven't figured out, I haven't ever pulled apart a 420a, but have plenty of experience pulling apart and rebuilding motors of all sorts, so I'm offering general knowledge. Good luck.

Its going to be fairly normal to get some scoring/wear on the piston skirts, because these are forged pistons, and the inherent "slap" when cold will cause this type of wear on the skirts. As a note though, this wear should be on the front and back sides of the skirt, not the piston pin sides of the piston skirt. Most importantly, how are the cylinder walls? If they do not have any major scratches/deep gouges, then a simple run though with a ball hone to put a new surface on them, would be fine. Inspect the pistons VERY well, esp around the ring grooves and piston top edges above the 1st top ring. Any slight deformation/melting at the top outer edge of the piston, and you will need to replace it. If all the pistons are in decent shape otherwise, then just get some new rings for it, set your proper ring end gaps(after you run the ball hone in the cylinders), and set the ring gap staging correctly before you install the pistons into the cylinders. Check all your rod/crank bearing surfaces as well, for any signs of major scroing/gouges. Plasitgauge the bearings to measure your oil clearance. If everthing checks out, the just do the hone and new rings, and that should be it. Be sure to keep everthing very clean on reassembly! And use some assembly lube on all the rod/mains. You will also want to clean up the pistons really good before you do any inspection or reinstallation with them..

Some scuffing is normal, as long as the piston stays the same color and you can't feel it with your fingernail. I see quite a bit of black discoloration on the blurry picture though. Personally I wouldn't reuse that piston, and be very suspicious of the rest.

Just got back from my mechanic's shop. I took in the worst of them to show him(one pictured above) He took a close look at the grooves around where the white is on the pics and basically said it's fried from detonation of some sort, most likely running lean. He said replace it and how are the rest of them. Well, they are all showing similar signs, so basically new pistons for me.

As for the rings, they looked perfect, all intact, kinda stuck in that one piston where it's burnt. The cylinders look great on the inside, valves look good, no signs of abnormal debris in the oil pan. Rod bearings look good so far, I will take a closer look when I remove the crank to check the main bearings. He recommended the same thing with honeing out the cylinders to remove any glaze they might have, new pistons, rods looked good, new bearings, new rings, and he suggested taking the head into his machine shop to ahve it cleaned and looked over and have them reassmble it. I'm still way under what he was going to charge to just do rings and bearings. I predict with even new pistons, I will be about the 1k mark or maybe 1200 with parts and tools, so I'm still way below what I would have spent with him...
Goes to show to dot eings yourself I guess, until it all goes wrong. I should knock on wood right now cause it's not back together and working yet!

Real quick on this little rebuild of mine, now that I need new pistons, what brand would you guys recommend going with the second time around? I know concept illusions has the je .020 with rings for about 499.00. Would you go with a different brand?
Here's my parts list so far, anything I'm missing, I'm going to be pricing this stuff out. Unfortunatly, Howeel willbe a main source for most of it.

Je pistons .020
Rings
Felpro gasket kit with head gasket
Clevite bearings (main, rod)
prothane motor mount inserts
160 thermo
better oil return lines
afx underdrive with belts
2.5 ic piping
larger ic 12x24x3
hks ssqv
ARP headstuds
silicone upper/lower rad hoses


I plan on running stock injectors and throwing the emanage on ebay to help get pistons. Back to 8lbs or less daily and a nice fcd until I can get the ms and wideband.

Thanks for everyones help, this has been quite the experience. I've actually been having an awesome time working on it, too bad it's my pocket book!

Originally posted by xceler8
Real quick on this little rebuild of mine, now that I need new pistons, what brand would you guys recommend going with the second time around? I know concept illusions has the je .020 with rings for about 499.00. Would you go with a different brand? Here's my parts list so far, anything I'm missing, I'm going to be pricing this stuff out. Unfortunatly, Howeel willbe a main source for most of it. Je pistons .020 Rings Felpro gasket kit with head gasket Clevite bearings (main, rod) prothane motor mount inserts 160 thermo better oil return lines afx underdrive with belts 2.5 ic piping larger ic 12x24x3 hks ssqv ARP headstuds silicone upper/lower rad hoses I plan on running stock injectors and throwing the emanage on ebay to help get pistons. Back to 8lbs or less daily and a nice fcd until I can get the ms and wideband. Thanks for everyones help, this has been quite the experience. I've actually been having an awesome time working on it, too bad it's my pocket book!

I'd just stick to off the shelf production pistons... nothing wrong with them. I think the piston rings are more important... but even more important are bigger injectors... cause without fuel, you'll just be back at square one... doesn't matter what you put in there, it will still blow!

There's nothing wrong with JE pistons and rings..They are very good quality, and very strong..Even the best made forged pistons cant handle the severe abuse of detonation..So far i've run almost 20 psi on the JE pistons and rings, and its doing just fine..people have run MUCH more power than I have on this setup..They should hold at least 600HP if not more, with proper tuning. I've found that 15 psi on stock igntion timing and 93 pump gas seems to be the limit for 8.8:1 compression pistons before detontation sets in..Either lower the boost, raise the fuel octane, or retard a few degrees of timing at 15 psi and above.

Also, I highly reccomend Modern Performance for the pistons and rings, i've built a few 420a's with parts from them, and they have fast shipping, and good customer service. Maybe not the absolute cheapest in pricing, but its worth a few extra bucks for the service.

Originally posted by XtremeRS
Also, I highly reccomend Modern Performance for the pistons and rings, i've built a few 420a's with parts from them, and they have fast shipping, and good customer service. Maybe not the absolute cheapest in pricing, but its worth a few extra bucks for the service.

I agree without a doubt excellent service and shipping. CI has nothing but a bad rep around and I would never order anything from them until they get things like cust. service, shipping timing, and reliability fixed.

Also there is nothing wrong with the injectors he's running now, as he states he will be running low boost. No need to step into larger injectors till he decides to turn the boost back up again.

I was running 440's in the car, the fuel wasn't a problem, the car was being setup for the ms. Only problem is it was being handled by the e-damager. I had a nice map setup on it that should have been plenty if not too much fuel for the car. It was detonating really early in the psi like 7 lbs or so, then it would kick in and shoot. It's almost like there was a delay in the emanage before it added fuel. No matter how much I compensated for it, it still happened. I tok off the profec for boost control and used a manual and it went away. I don't know, it's said and done now. things will be done differently next time. I'm going to spend more time setting the car up with stock injectors and low boost and try to get the ms in and running before I make an injector change back again.

In the meantime, I just got outbid on ebay for a friggin hks bov and I'm a little pissed. The bastard came in with 30 seconds left and got me by .99! Oh well.

thanks for the advice guys- Any other parts I should be looking into while it's all apart?

Originally posted by xceler8
I was running 440's in the car, the fuel wasn't a problem, the car was being setup for the ms. Only problem is it was being handled by the e-damager. I had a nice map setup on it that should have been plenty if not too much fuel for the car. It was detonating really early in the psi like 7 lbs or so, then it would kick in and shoot. It's almost like there was a delay in the emanage before it added fuel. No matter how much I compensated for it, it still happened. I tok off the profec for boost control and used a manual and it went away. I don't know, it's said and done now. things will be done differently next time. I'm going to spend more time setting the car up with stock injectors and low boost and try to get the ms in and running before I make an injector change back again. In the meantime, I just got outbid on ebay for a friggin hks bov and I'm a little pissed. The bastard came in with 30 seconds left and got me by .99! Oh well. thanks for the advice guys- Any other parts I should be looking into while it's all apart?

Oh sorry, I missed where you said you had 440cc injectors. Anyhow, I have had back experiences with the emanage... as you said, it seemed delayed in reacting to the changes of the engine... we had no idea why, so I buckled down and bought a wintec3... :/