I bought this shortblock from a vendor here. Its down around 40 rwhp and occasionally made a bit of piston slap noise but these are LSXs and we all know they do that. When I first put the motor in and broke it in, I took the heads off to change them out to a differnet set and noticed some scoring and a gouge in the cylinder walls. I called the vendor and showed them pics and they said it was no problem and to run it. Well I'm doing more head work and now there are a bunch of gouges and lots of scoring in all the holes. Only a few have deep fingernail catching gouges but they all have scoring or fine scratches. All the marks are in the 12 and 6 o'clock positions. It looks like to me the piston is rocking in the hole and the skirt is making these marks. Explains a bunch of my issues. This is an uncharacteristic issue from this supporting vendor and I'm not sure what they are going to do. Motor has 3k miles on it.

Can I get some of y'alls opinion on this? What do you think the problem is, if you were the vendor what would you say? If the vendor does not stand behind their work, how long do you think this is going to last? (I'm going to have to save money for another motor, I'm having a pretty bad last few months here). Maybe I can get a bunch of comments together to show the vendor. I've already had 3 mech's look at it and they all agree with my diagnosis, maybe I'm just looking for some more support.

I don't want to give these guys any bad press yet because I'm still not sure where they stand. Like I said this vendor has always been awesome and I've backed them countless times when folks are asking where to get a good shortblock. Maybe the machinist just had a bad day, or maybe the pistons were a bad lot. What do you all think? I'll take some better pics in the daylight but here are some quickies.

 

The first picture the marks are too high to be caused by the skirt. The other pics dont look that bad. The third one I cant really see anything at all. Some vertical marks are normal. Dont know if anything in the photos would equate to a 40 HP loss. Does it smoke? If you pull the PCV out is there crankcase pressure?

 

what is weird is that its just at the top and now all the way down the cylinder wall. not really sure what to this about it to be honest. the rings are the only thing that the groves at the top come in contact with. i am wondering what they look like and how much end gap they have in the bore. are you using a bottle by any chance?

 

There are a few of the wide gouges down farther in another cyl. Hard to get a pic but I will get some more in the light. Motor has seen no spray, no track time in fact. I tried to make a pass and blew a rear before this winter. So, no real time on it at all.

I know the skirt is not up there. I think the lighter scores are from the skirt. I know some wear is normal, but my old motor had 15k on it and nothing of the sort. 3rd pic look down in the hole towards the right. Another gouge lower.

The pistons rock quite a bit in the hole if you push on them. I actually think the piston is coming up and when it fires it rocks over and slaps the side of the bore. How much should the piston rock? There is probably 1/16th of an inch of play back and forth.

I appreciate all your thoughts.

 

Lots of forged motors do that, I havn't seen any that didn't have some small amounts of vertical wear marks like that. Those actually look fairly mild to me, I'd be surprised if that was worth 2-3 hp of loss. Real problems would show up in a warm-engine leakdown test.

You also have to remember that on forged piston engines, the piston to bore clearance is normally .0045"-.0055" and more depending on piston material/design, actual bore size and manufacturer recommendations. Whereas a stock hypereutectic piston motor "should" be .0025"-.003" in a LS1. Until a forged piston motor fully warms up, the piston is loose in the bore that extra few thousanths until thermal expansion closes that gap. Thats why most forged piston motor sound like diesels until warmed up.

A very prominent engine builder once told me that if I wanted my engine to look new... to never start it up. Of coarse I've never listened to that advice.

 

I checked my 50,000 mile 436 stroker engine when my heads were rebuilt and there wasn't one single tiny little scratch of any kind in any of the 8 cylinders, especially vertical gouges/scratches. Smooth as glass. Maybe its normal, I'm glad mine is abnormal. I'd be wanting a new short-block and I'd get it. Sucks when you have to tear an engine down for something else and you find more bullshit. Like I said, maybe its normal, but after seeing mine go 50,000 and still be perfect, it would be a little unsettling to see in a 3,000 mile engine.

 

I've taken apart quite a few engines, and never seen anything like this, especially after 3k miles. But, I'm open to educated opinion. Let me put it like this... if this was YOUR car, would you just put it back together and call it good? Plus I know its hard to tell by looking at pics so this is all just good discussion. I've always gone by the "finger nail method". If you could feel it with your nail its not good. Many, many marks in the bore can be felt with the nail. Hell, believe me, I'd love to just call this good and move on. Just want to get some backing either way. Its no slouch, it made 470 rwhp with the small heads. I've just never seen big marks like these in any other motor. The forged and more clearance argument makes sense to me but its tough to swallow. Run it till it ***** and pack pennies away for a 441?

Oh, this isn't my first forged motor either. I had a 4.3 that ran 20psi thru it. It was loose and didn't have any marks at all.

 

If it were mine, and looked just like those pics I probably wouldn't look twice at those marks. They really don't look that bad to me. I've seen much worse with no adverse effects.

How much power did that 4.3L make on 20psi? I've had a kick to build something really small cid and throw 30+psi on it, but we'll see what I end up with. Cheap and lots of boost are two of my favorite things, especially when in the same sentence.

 

I was also told by a few different sponsor/builders, and the builder who re-did my heads, when my heads were off, to feel the walls with my finger nail, they said if you can't feel any, you're good. So thats what I did, I felt NOTHING AT ALL and couldn't see anything with my eyes after 50,000 miles with a big stroker engine. Since I felt nothing at all I didn't push the issue to have people saying, "aw, thats not a big deal" or "thats normal for a high mileage engine".

Do a poll and ask if you should have that many gouges/scratches. Vertical scratches means something is not perfect, and a perfect engine is what I'd certainly want. Let the people who don't mind "normal" gouging/scratches have them, not me.

.

 

It made 640 rwhp the first go round. I put a bigger balancer on it to up the boost and on the way to the dyno I hit a wall. lol. Yeah I got no luck I'm thinking it was close to 680.

This is my poll. I'd love not to have scratches but I do, so I need to just run it or pull it. I'm out of money so if the vendor says they are not going to cover it, I'm screwed.Its not the light scrathes I'm worried about, its the deep gouges where the piston is rocking back when the plug fires and smacks up against the wall. That just can't be good. I mean if there is enough room for the slug to rock over and do that kind of damage, what is going to happen down the road? Where are all the metal shavings going? I think if any racer found this they would immediately stop and rebuild the motor with pistons that belonged in there. I guess you get what you pay for. I've never seen a Cartek motor look like this. They are forged. I put together quite a few motors, they all didn't look like this after 3k miles of street driving. I even had a 69 Chevelle with horrible piston slap and all it did was make noise. Teardown showed no wear. Picture this: piston comes up in the hole, plug fires, bam! the piston rocks over and bumps the wall. I'm no expert, but I don't think that should happen. The deep gouges are on the top cause that's where the plug fires and slams it. The bottom gets light stuff from the skirt. In the bottom of the hole, the opposite happens but no super deep hits cause no explosing working to slam it against the wall. So, just some light scuffing there. I dunno, maybe I'm retarded. Again, I appreciate all the comments, just talking myself through this. You can imagine how this might raise your blood pressure. I was going to spray this motor. Now I think I bought a $4500 motor I can't beat the crap out of.

 

Oh, no smoke. Uses oil. Probably blow by and the LSX intake ingestion. That's where I think I'm losing power. Compression is great 180-190. But, like was mentioned leakdown is where you will see the failure. I think the holes were honed too big. My dad has my bore gauge, I need to take a look see.

 

The marks above the top ring are pretty common in high hp engines, but they should not be there in a happy engine. I would take the engine apart and find the root cause of the damage. You will probably find the skirt of the piston collapsed, this is most common on nitrous engines but can happen na also.
It is also possible that something got between the pistons upper land and the wall and caused the scratches, if this is the case it will be still there.


Kurt

 

Look, its simple, every sponsor and engine builder out there has built a PILE-O-****....and they will do it again...its the nature of the business....it's impossible to build every engine the same and with 100% perfection. ARE rebuilt my engine and they knew damn well they really didn't cause the problem I had, good PR. Your problem is a BUILDER screw up for sure, therefore:

IF ANYTHING.....it would be nice PR for your builder to replace/fix it. And I don't know much about matching parts, but if you have the wrong sized pistons in there, well thats one of the builders PILOE-O-**** engines.

Get a new one. Unless you dropped a handful of metal shavings into your engine, what esle would cause this?


.

 

Not impossible.

 

I agree... but will the vendor? I've recieved several PMs from members who bought motors from the same vendor with similiar problems. So, it looks like I'm not the only one. There may have been a bad run of something, pistons, machinist, etc. The vendor sees this and it looks like I will just have to "live" with the motor this way. I like what Kurt said, its common, but that does not mean its supposed to be there in a happy motor. I paid for a happy motor. I am still sticking to my guns about a mismatch whether it be due to cheaper, off the shelf pistons or some other cosmic assembly issue. I also like what Katech had to say. No, I LOVE what Katech had to say. Shortblock buyers are you listening? You get what you pay for. Sometimes its worth a little more to get a motor from somebody like Katech or Cartek or some of the other vendors here. 403s are not 403s. You can build 100 motors that come out right but its the handful that don't that matter. Crap happens, but how as a company are you going to handle that crap? Nevermind that it should never happen to begin with. How are you going to handle it if it does? Remember the SLP fiasco? How much business did they lose over that guy posting about their bad motors. Guess what? They were right, the motor was put together fine. But they still lost business. I know of at least one customer that went elsewhere... me. I live 15 minutes from them but bought a motor from somebody half way across the country because I heard good things about them. Had I known I was going to get a block like this, I'd have saved another grand and gone with a vendor who says, "not impossible". They are out there. You are reading this. Like W2W says its not happy. Make it happy.

Oh, and there is nothing in the motor and nothing anybody is going to say to make me believe that. Exactly, unless I dropped a handful of shavings in the intake, what would cause this? I gave you my theory what's all yours? Bottom line is those deep gouges were not caused by debris. Its caused by piston to wall contact. Period. What could cause that? Nothing on my part. Its a build issue. Builder, what are you going to do about it?

 

I'm with Katech, if it's not RIGHT, it does not leave the shop.

 

Oh, and just so you know I'm not going to be a bitter a hole over this. I see a lot of people lose their minds and go on for months. Stuff happens. If the vendor says that is the way the motor is supposed to be then I'll let everybody know and move on. I've recieved a bunch of messages from folks saying this aint right. Reputable builders that do not want to come pout publically and trash another vendor. I've got a bunch of reasons why this happens. I'm educated now, so its a good thing. Maybe the moderators should make this a sticky so folks who are looking to buy a motor can see who thinks this is unacceptable and who doesn't. Pretty valuable information.

Heck, I could have done that assembly myself.

Lol, I just looked at these from my work computer and I can't see crap either! I guess my super bright monitor at home works better.

 

AintQik,
I don't think anyone can tell whats wrong with your engine by your pics, I know I can't. For me to draw a conclusion based on pictures would be careless on my part. Send me the engine if you like and I will report to you and the builder what I think went wrong, and it will cost you nothing but shipping.

Kurt

 

He's exactly right. You can't tell a damn thing by those pictures. Someone can guess and guess and guess, but without tearing it down and inspecting it further you won't have any concrete answers. If you come up with claims that you can back up with real evidence and the vendor STILL doesn't want to do anything about it, then start the rant.

BTW Kurt, that's an awesome offer.

 

Kurt, that's an awesome offer! But I think in the end no matter what, it is looking like the vendor thinks this is "ok". I also know that it's near impossible to correctly diagnose the problem from some stupid pics but I wanted to get some ideas. I'm pretty confident I know what's wrong just wanted to hear some other suggestions.

The thing to note, is that every suggestion here in the open and in my PM and email box has been build related. Not, I did something wrong. (Other than the metal shavings thrown in the clys comment) So no matter what the final verdict is, I think the blame lies with the build and the machineing of the components. That's pretty much what I wanted to hear and what I wanted to pass on to people. #1, this aint the way its supposed to be and #2 its related to the build. Additionally like I said I'm looking at these pics on my work monitor and they look horrible so I see where you guys are coming from. At home you can see all the way to the bottom of the hole and the marks are very clear.

I will not keep this motor in the car and I will not spray it like I wanted to. I'd just be worried that stress would slap the wall too hard and crack it. I will run it until I can afford another short block build. Since the vendor think this is acceptable, I'll go to one of you guys that thinks its not and sleave the thing to a 441. Does sleaving still cost close to $3k? That's going to hurt. Does the price change according to the size jug you are going to use? In other words would a sleave to 427 bore be cheaper than a 441 bore? I imagine its the same.