700r4 noises or 383 stroker piston slap?

[stringpickin]

Hey ChickenWing,, no, have not just got done building a house. Just got done a few months ago with a very expensive super fancy kitchen I built and installed in Arizona, from northern Ca.. Man do I like your signature too. The goverment is supposed to be run by the people not some (rich and corrupt) people.. It almost seems impossible that if a Tea party had to happen the modern weapons would nearly make it impossible. Oh well, one world system coming our way whether we like it or not.. interesting times. Forget about the weapons, who needs the hi tec weapons when the blindness of the majority of the people to see the real garbage that is going on is so prolific. Sorry,, didn't mean to turn our Kool Truck board in to a dialog on the rich getting richer.. lol.. consider it done.. ............

[stllookn]

string, the problem with the 289 was piston slap...timing only makes the noise more or less noticeable, that is all. It is also a way to diagnose piston slap. If you retard the timing to 0 degrees you will likely lose considerable performance depending upon what your timing is supposed to be.

[stringpickin]

UPDATE.. The engine is being broken down by Smeding Performance. Lets hope the problem is easily found.. hope hope hope.. string

[chickenwing]

Hey! You never called me up for the engine pull!

[Professor]

I had nearly the exact same symptoms in my recently-rebuilt, low-mileage 350 and th350. Drove me nuts. The flex plate LOOKED fine, just by looking with the cover removed. However, I unbolted and slid the torque converter back and found that the center bolt holes on the flex plate - where it bolts to the crankshaft -- were broken out. You might not see this if you just unbolt the converter from the flex plate to rotate the converter on the plate. You have to be able to see the center of the flex plate.

[stringpickin]

UPDATE: The Motor is broke down. Being it only had approx. 900 miles on it, wear marks were basically non-existent because the noise happened only when the motor was cold and disappeared when up to running temp. What they found was when they measured the cylinders. Approximately 4 cylinders are over sized by enough to cause a few pistons to slap inside the holes. But was not easily seen because at the top of the cylinder they measure within spec. just barely. So when they measure down inside where the piston rings had been running against the bore the measurement was notably larger than allowed specs. So the consensus is, before the ridges of the Honing of the bore were knocked off the cylinder bore was within spec. So my consensus is this. The engine should have never been put together with the specs that close to the outside acceptable tolerance.
If they would have measured the bores before they put the motor together they would have found that it was on shaky ground. My opinion they would have and should have come to that conclusion. Anyway, they are going to take the now seasoned block, and bore it 30 over and rebuild it from the ground up. He assured me that he doesn't want it back again and they are basically going to blueprint it as they put it together this time.
He said they have never had this happen to them before. Apparently they never measure the bores on the brand new blocks they purchased from GM. Apparently they come bored and honed ready for assembly, then they just throw their parts in them. He said they measure the pistons to make sure they are within spec across the board, but had never found it necessary to measure the blocks. Oh well. I got the one that was a little too sloppy. What an expensive waste of time this has been for me. I cannot wait until it is in my truck and running correctly, with zero knocks. Anyway, that is the scoop. Thank you everyone for your input and concerns... Barry

[stringpickin]

YES!!! Engine has been picked up from the builders and is enroute and to be delivered monday afternoon. I might be able to use my truck for the bluegrass festival after all. What they did for me is, Took the brand new (broken in and now seasoned block) which is good because block will react very evenly now when she gets hot again. Serious race engine builders prefer a seasoned block to build, so I am going to go with it being a good thing. The builder told me that he basically blueprinted the motor for me. Told me he knows I am going to be listening even closer now, so he made sure it went together perfect. Anyway, I will be very happy to get her back and in and running. Maybe I will finally be able to enjoy my rebuild and restore of my chevy.....with a motor that aint clankin.. won't that be nice.. Will let you know how the start up goes.. ciao for now..

[cadiac]

My experience with piston slap, -I sold a low mile 305 from a 77 Nova because it scared me. That buyer ran the crap out of it in a 69 3/4 gmc and it never failed. I found later that that year commonly had piston slap. I had a rebuilt chev 350 that I put 60-70 K on before selling to someone who put it straight in a car. I have a 189 K LT1 thats slapping away and runs like a striped @$$ ape. I have a 40K Cad 500 (in 86 chev pu)that started slapping around 5-10 K. It's getting a tad louder but still fades and is gone above 1200 rpm and warmed up. That engine works really hard pulling a car trailer and putting up with my having fun. It is disappointing I know, -I used to worry alot. But I haven't personally heard of a failure from it. Just my experience and 2 cents.

[chickenwing]

When ya gonna install it?

[stringpickin]

Hey Cadiac.. Yeah, from what I have read, it is not usually ever a problem that is going to lead to catasrophic engine failure. I have found some reports that seem to say it does shorten engine life depending on degree of slap. More severe slap more possibility of the rings are torqued causing premature wear. Some motors with piston and stroke ratios where it allows the rings to get down in to the area of the cylnder where the slapping has occured can cause early wear. But generally as you say, they run for many thousands of miles. Of course my beef is I spend 4K on a brand new motor for my rig, and I am supposed to accept knock knock knock as being an acceptable situation? nope.. I want that baby to run like a sewing machine. Try to convince someone if you are selling it, ah shucks its just piston slap, no biggy.. then also if you have other noises clanking and bangin what happens if some time down the road another noise develops but you can't hear it cause you think everything is piston slap. You could destroy your motor because undiscovered noises in the early stages. And not to mention, how can they possibly last as long when they are beating up on themselves. Quite a hassle to have it fixed and costing me down time and costs. But, I will have it running right when done I hope.. in theory.. hopefully worth the trouble.. lol

[stringpickin]

hey wingman of the chicken,,, well,, being delievered monday afternoon at the shop where I paid the guys to pull it.. I half thought about towing home dropping it in over here. Kind of a long story, you know how people break things and never admit to it. Well, to keep the ground fertile I basically had to say, okay yeah yeah, your right, you guys couldn't have done that. thats the short version.. lol.. So, to save possible earthquakes I am going to have them drop the motor in, and if they seem to give me any troubles then I will tow it home and hook the rest of it up myself. Right now it would be hard to take it away from them when they have stored it over there for over 3 weeks.. But if things start getting goofy I won't hesitate to bring it home and button it up on tuesday or wednesday.. you chompin at the bit?

[cadiac]

Ya if i spent a bunch for a premium/special rebuild, -they would have it back in there shop.

[chickenwing]

lol, naw.... If ya needed me, I'd clear my schedule for a day.