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Map63Vette

Map63Vette

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Well, I finally managed to get a few runs at the track after my swap. They weren't super impressive, but they're not all that bad. I'm moderately pleased, though I know the car has more in it (5.7 with stock internals, Indy Mod Man intake, TTI headers, and Megasquirt fuel injection, ~3400 lbs. with me in it). The track was pretty bad at the line, everyone was having a hard time hooking and I blew the tires off every run, but my best was a 13.99 at 103 or so. I think the car should be good for a 13.5 at least with a better launch, so all in all not too bad an afternoon, though my oil pan problems came back and some potential other issues. Got of video of the last run [ame="http://youtu.be/FlxXrYwMSeI"]http://youtu.be/FlxXrYwMSeI[/ame]

I made four runs total before calling it a night (or at least before my pan called it a night), but I noticed I was starting to blow smoke out of the pipes on the top end of the rpm through all the gears that I've not seen before. It was pretty smokey behind me by the last run, one of the main reasons I called it for the evening. I'm not quite sure what to think of it, the car doesn't seem to blow any smoke on first start or just driving it around town, but when you wind it up all the way it will puff a pretty decent cloud around 5k rpm and up or so. I checked my A/F ratios on a datalog and they're pretty consistent all the way through the rpm range, so pretty sure I can rule out fuel. I would think if it's rings it would do it all the time, especially when cold, but it only seems to do it at high rpm.


I think I may be in the market for a new short block. I wasn't pleased with the ring gaps on the replacement pieces I got, they were on the very edge of the tolerance given (.024 or something like that). I should have just sent them back in the beginning, but I was too eager to get the thing started up so I rolled with it. Not sure how the sleeve is working out either, so I've been thinking about starting over with a good block and doing my head and cam build on it and just swapping the setups. Anyone have any leads on a nice short/long block in the Midwest for cheap? Looking for something with a good bottom end that I wouldn't really have to pull apart, don't want to mess with rings and crap again. It would be nice if it came with a set of heads as well so I'd have a pair to core for performance ones. Don't need any electronics or anything.
 
Try a simple PCV swap. Does the modman allow forcrankcase ventilation? If not that would make sence to me.
 
Yeah, I have a PCV valve in it. Used to just use a breather, but it was always wet around it. The air filter is really oily where the PCV is attached to the base plate as well, so I have a feeling I either have way too much crankcase pressure or way too much vacuum pulling on it. I was going to try hooking up a pressure gauge on the PCV to see if/what it read. Any ideas what it should be other that not much?
 
Im not sure on how much vac it should have but it is supposed to pull between the air filter and throttle blades. Another option would be to install a catch can. Between the PCV and filter. This would trap the oil from going into the motor. Here is the first one that comes to mind. http://www.custombilletstore.com/Hemi_Oil_Catch_Can_p/20010.htm

They will typically catch about 1-2 tablespoons of oil between oil changes. You can find cheaper versions on eBay, might be eorth a look. But it's more of a band aid fix, are you running the factory windage tray/oulpan gasket? That will help too. The biggest problem though could be the piston rings. If your loosing compression to the crank case your forcing the oil vapor to go somewhere with the motor running plug the PCV line, with your thumb, wait a few seconds and remove and listen for air pressure there should be none. If so I would conside doing a leak down test, to see what cyl is leaking and start there. Is it possable the piston rings were not set up correctly on one piston or got moved durring install? And now the gaps are lined up. That would cause the pressure.
 
I am using the stock windage tray/pan gasket. Need to try the PCV thing, just been hard to convince myself to work on it since the pan is still leaking. I just can't get the damn thing fixed. Fairly possible the rings are set up less than ideal on some cylinder. I did them myself and tried to pay attention, but who knows where they ended up by the time I got them in. I know I had to reuse one old compression ring (put it as the second ring down to try to reduce any effect it has) and one old oil scraper ring because my ring compressor was having a bad day when I put the engine together and bent the two. I would have thought rings would show bad all the time though, especially when it's cold. I'm pretty sure there's some pressure in the crankcase because the last time I plugged the PCV line (was causing a high idle when plugged into the carb base) it started smoking out of the pan rail seal. The sleeve might be causing issues too, need to see about checking the cylinders I'm most suspect of if I can come up with a way to get a compression tester all the way down the spark plug tubes.
 
Leak down test first. Blowing oil on acell, or let of the gas-let off is valve shields. Every engine I have seen on a dyno gets nasty on pull back.
 
It's only on wide open and only at the top end as far as I can tell. I can bury my foot in it and watch the rear view mirror and it doesn't blow a puff I can see until it hits maybe 5k, then it's a full on plume all at once it seems. As soon as I get off it looks like it goes away. Need to get someone else to watch and see when it starts for sure. I'd try just winding it up in idle with no load, but since my pan just dumped a quart of oil over night through leaks I just drained it so I could try to salvage some. The bottom of the car is soaked in oil, half way down the pipes and the whole bottom of the trans, though it does look like it's coming out of the pipes themselves and not just from under the car. Need to see if I can find a pipe long enough to go down the plug tubes and get a hose on it for leakdown.
 
Cool car... Those ring gaps are fine.... Dud u Che k ur spark plugs?
 
Replaced half of the plugs when I bought the car, 16 iridium plugs at once was a little too much to handle, lol. Hoping that maybe the problem is related to the oil pan. I think my patch started getting worse the more runs I put on it and I don't recall the car ever doing the smoke thing in the past before the pan was leaking. Looking into getting a new pan now and will try to wind it up again after that to see if it still does it. If so then the block search may get a little more serious. Though a new block is a good excuse to finally do my heads and cam :). Rear end is the next thing on the list to sort out, it doesn't just whine, it whistles, but only at cruise at certain speeds. 45 is pretty loud, 70 is dang near ear splitting. Just did new bearings back there too, hoping the gear set just gave up and that I won't need to put another set of bearings in.
 
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