OK so here are the results of the teardown of the motor I blew last fall. I blew this motor by accidentally running 17+psi on pump gas. I'd just changed a bunch of stuff which affected how much boost I made, got a little too greedy with the boost controller - obviously didn't have it tuned for that much boost.

The top of a good piston





Two front pistons - driver's side and center - are the ones that melted. FYI pistons are supposed to be circular. These ones as you can see, are not.

 

Results of melted pistons effects on cylinder walls - aluminum melted and deposited on the cylinder wall. Notice in the first picture, a good wall is visible with the crosshatch from the factory hone still evident

 

Heads - notice there are zero signs of detonation on both the pistons and heads. Headgaskets were perfectly intact. This was the result of a thermal meltodown that occured on one single run, something like this is not something that happens over time.






Rod bearings - the bearings were starting to flake. The film strength of Castrol Syntec 10w30 was starting to be overwhelmed. This is damage that occurs over time. There was all sorts of gunk in the oil ports for the rod bearings on the crank. I was unable to remove the block girdle to check the main bearings (the main bolts are a completely retarded design btw), but the engine doesn't spin easily with the rods and pistons removed, so those bearings might be shot too. I'll update on that. Sorry these pictures didn't turn out too well.

 

Just for comparison sake - from left to right - VQ30DE rod and piston, VG30E rod and piston, Honda F22A (Accord 4 cylinder) rod and piston.

 

Lastly, a couple pics of the 3.5 that's getting ready to go in the car shortly. Astute readers will notice that those are 3.0 valve covers on the 3.5 We (maxmaxima91 and I) CNC'd down the cam caps and then welded the VTC oil passages shut to work with the 3.0 valve covers.

 

Well i know where you been all day now man. Good work . I hope to see that runnig around here in Kalamazoo soon.

 

Interesting and nice work on those covers.

 

Haha going for the stealthy swap, nice pics.

I'll post up my seized #2 bearing pics tonight (from the first engine), you'll like them..

 

Nice VQ30 you got there

 

wow those pistons got F-ed up.

very sweet setup and very clean!

 

wait, what is the advantage to having the 3.0 valve covers on the 3.5?

 

I did it because I think the black valve covers are ugly as hell, and one of the VCs on the 3.5 I got was cracked. I don't know of any advantage per se.

I can glass bead stuff at work. so i glass beaded everything i realistically could to make it as clean as possible including the valve covers to clean them up (forgot to do the passenger side engine mount though, so I'll have to do that later).

 

Wow Neal, that looks really nice. Really impressed! You should paint those the crank pulley and the one to the left black. Also, you should paint those manifolds. Anthony used some off the shelf stuff on his Fury and it looks really nice for a rattle can job.

 

Very stealthy and nice, Do you plan the keep the man N/A? or N/A for now?

 

Finally some progress I see, good stuff

 

Love the pics - looks nasty!

I'm considering stroking my VQ30 into a VQ33 using VQ35 conrods/crank (a whole VQ35 engine is still very expensive over here in New Zealand). Seeing as you have an engine in bits would you rekon its possible to change the crank & conrods without popping the head off? It would be a real time and money saver. Unfortunately the VQ33 isn't very well documented!

 

No, pistons have to come out the top of the block.

 

cant then come out threw the bottom if the crank and oil squirter's are removed? I'm not sure last time i took them out threw the top also.

 

But is it not possible to sneak the pistons down far enough to get access to the pins? (or am I just dreaming? )

 

You're dreaming. Take a look at a VQ30 block and you'll see. A) you can't get most of the pistons far enough down to even clear the pin before you hit the casting/main bearing saddles. B) even if you could somehow clear the pin height wise you'd still have to spin the piston a good deal, almost 90 deg maybe, to pull the pin out, which is not physically possible (spacing between the main bearing saddles...)

 

Alrighty thanks for the info. I haven't stripped down a VQ yet - the furtherest i've gotten is replacing the timing chain. Its definately going to be a learning experience and a half

Oh, and end of thread hijack

 

how much are vq35s going for in NZ?

don't worry about hijacking the thread, it's good to see a new member making good posts as their first posts instead of stupid ones

 

Thread Jacked. It is now mine. LOL

Is that the stock flywheel?

 

Nope thats a fidanza

 

Not sure of the exact price but it would be high. Our 5th gen maximas don't come with 3.5's here unfortunately - only the 6th gens do

I figured I might be able to order in the crank/rods from Japan (or possibly from the US). Looks like I might need to import some head gaskets and head bolts now too - speaking of which are the head bolts torque to yield on the VQ?

 

Sweet.

If Maximas were more widely known you might be able to fool a few people with the 3.0 VCs (even if you have the 3.5 coil packs coming up through 'em), but it still wouldn't be too hard to spot the snail...

 

i didn't use the 3.0 valve covers to fool anyone or anything like that, I just don't like the looks of the plastic valve covers.

 

Gonna go for a polish too?