DandyMax

iTrader: (7)

Well that didn't take long. Out doing some tuning runs tonight in anticipation of racing tomorrow with great weather. Not that I've torn anything down yet but I'm pretty sure the revup oil pump blew out on me, at least the oil pressure cut-out switch saved the engine this time.

Sooo.. who wants to speculate on why the revup pump went (assuming it did)...

nismology

iTrader: (8)

This really sucks Dan. And here you thought you had the oil delivery issues completely ironed out.


The first thing that comes to mind is aeration. The revup pump is fine to 8500 RPM in the VQ35 applications. I'd like to compare the 3.0 and 3.5 oil pan baffles side by side.

NmexMAX

iTrader: (22)

. . . MoTeCM600

DandyMax

iTrader: (7)

Well I gotta say that cutout switch has paid for itself (not that it was expensive.. haha). I was never fully confident in the revup pump after taking it apart, but I was keeping my fingers crossed it could handle 8000 rpm. I'm not quite sure what the culprit is. There are 3 things in my mind right now:

-aeration/cavitation
-inadequate strength gears and/or casing
-torsional vibration/balancing problems

It's tempting to get the Nismo pump, although it's hard to swallow the price tag - but it is spec'd to be able to go to 8500 rpm.


Edit for your edit: yeah good point Richie's pump lived at 8k+... got any pics of the 3.5 baffling? I can supply 3.0 pics...

DandyMax

iTrader: (7)

Shhhhh...

(but what does that have to do with the oil pump?)

NmexMAX

iTrader: (22)

Nothing, just a subtle hint that I've been up/studying

DandyMax

iTrader: (7)

PM me then

DandyMax

iTrader: (7)

Hmmm, when Richie sold the car he listed the build list.... he had a Nismo pump and a Fluidampr

http://www.my350z.com/forum/showthre...=247357&page=2

post #29

KRRZ350

iTrader: (29)

Oooh Ooooh, I love these games! Weak gear broke, possibly shattering the housing as well. Someone needs to start making better gears for you crazy bastards trying to spin ridiculous rev's. Glad to here that the cut-out switch worked

nismology

iTrader: (8)

Yea I remember seeing that. I was actually referring to Audible Mayhem's all motor project. He revved it out to 8500 RPM on the dot using the revup pump and it never failed. Then there's rocks (i think that's his SN) who revved his built revup motor to 8000+ RPM on the standard VQ35 oil pump without fail.

nismology

iTrader: (8)

Sorry mate but I don't. My 3.5 oil pan is still attached.

We really need to compare the 3.0, FWD 3.5 and RWD 3.5 baffles. I'll see what I can dig up.

DandyMax

iTrader: (7)

Yeah I know Richie wasn't the only one, I was just going through some of his old threads/pics first...

But how many times did the others rev up there? If it's only a couple, on a dyno, isn't the same...

Maybe Grey will have some pics, he just put together his 3.5...

eng92

iTrader: (3)

FWD VQ35

grey99max

iTrader: (12)

Daynm, Dandy, if you didn't have bad luck, you'd have no luck at all.....

I have both 3.0 and 3.5 upper oil pans in the garage. Do you want my usual 'bucket' of photos of each? Or are you looking for something special in them?

EDIT: Woops - I checked and I only have a 3.0 pan left. I tossed a lot of surplus stuff a few weeks ago, and the 3.5 pan must have been in the pile. I couldn't use it with the external oil cooler, 'cause the filter would hit the traction bar on that side.
.

nismology

iTrader: (8)

Dynos, street driving, some runs at the track, etc.

redls1

iTrader: (2)

http://www.my350z.com/forum/showthre...light=oil+pump

not totally related but also another failure.

96sleeper

iTrader: (4)

Does the pump location have to be checked with a feeler gauge when tightened? I know the LS1 pump is finicky and will break if not installed perfectly. Either that or some vibrations appear in upper rpms where not many have ventured...

nismology

iTrader: (8)

One in a million. You'd be hard pressed to find others like it.

He wasn't really revving it particularly high either. Apples and oranges.

nismology

iTrader: (8)

There are no special considerations when installing a VQ oil pump. Just line up the dowels and the flats on the crank with the inner gear and torque to spec. Furthermore, I can't think of ONE VQ35 oil pump (in a VQ35) that shattered from high revs (excluding accidental overrevs/mishifts, etc). That's why the VQ30 crowd looked to VQ35 oil pumps for better high RPM reliability in the first place. I truly believe the 3.0 itself is what's causing these failures. We just need to pinpoint the exact reason why.

Jime

iTrader: (10)

Geez Dan, thought I had all the bad luck. Was hoping to surprise you and show up at the track tomorrow. I have spent the day doing some tuning with the new UTEC software and was going to check it out at the track. Guess I had better make sure I keep it below 7200.

PS My last engine was because of an oil pump failure so there is at least one VQ35.

nismology

iTrader: (8)

Was there an accidental overrev involved? Even if this wasn't the case history says rev up oil pumps when used in a VQ35 don't fail at any of the revs that people have thrown at it. I'm a firm believer in viewing things like this in a historical context.



Heck, krismax was revving his VQ35 w/ standard oil pump to 8000 RPM on a regular basis when he still had his JWT ECU.

Jime

iTrader: (10)

Ya it was accidental (8500) but not the same day as this one.

gtr_rider

iTrader: (50)

That pic scared me for a second, warning please.. lol

and wow that sucks about the oil pump again

505max94se

iTrader: (15)

I think you need one of these...

http://www.jegs.com/webapp/wcs/store...64068_-1_10453

Or even better, do a dry sump set up

I think it has something to do with the harmonic vibrations of the crank.

t6378tp

iTrader: (69)

somebodies been watching horsepower tv

Nealoc187

iTrader: (23)

VQ30 oil pan pics

95BLKMAX

iTrader: (10)

Jim, those are not wounds, those are battle scars from trying to control all that horsepower! . glad you seem to be getting better day by day!

Dandy, sorry to hear about this man. Let us know what you find once you tear the sucker down

Matt93SE

iTrader: (44)

Excuse my ignorance if I'm jumping in things you've fixed 2 years ago, but these are pretty basic and I haven't seen them mentioned..

what kind of UDP are you running?

Have you ever had it balanced w/ the crank as an assembly? If you're spinning those kinds of revs constantly, you REALLY need to be balancing the rotating assembly.. dumping in another junkyard engine with a new oil pump is just polishing a turd so to speak. I hope you're doing some sort of prep to these engines first.

a true harmonic damper would be a very good idea as well. dump the ultralight aluminum crank pulley. they make it rev nice and fast, but you need something more reliable to keep the vibrations down on the crank. I'm going to jump out on a limb and say that's a very likely culprit of why you keep blowing things up.

nismology

iTrader: (8)

Well every nissan engine in the modern era is internally balanced from the factory but I suppose that maybe the VQ rotating assembly wasn't balanced all that precisely to save money on tooling or the like. The more I consider the possibility of what you just mentioned, the more it seems more realistic to me than just aeration. Most, if not all of the VQ35 guys revving to 8000 RPM and beyond have had the rotating assembly balanced (aftermarket internals) now that I think about it. Excellent point Matt.


I guess crank-mounted oil pumps are the canary in the mine, so to speak. But just so we're on the same page are you suggesting that there's an out-of-balance scenario or crank harmonic vibration is to blame?

DandyMax

iTrader: (7)

Thanks for the input Matt (and everyone else for pics etc)

Note that I haven't actually torn anything down yet, but assuming the pump has gone, then after taking a couple days to consider everything, this is my conclusion also (ie -vibration). I'm sure the powdered metal gears (vs billet) don't help but I didn't balance it and I was still using a Motostorm UDP. The Fluidampr made for the 3.5 looks very tough to adapt due to the extra timing ring.

My first engine was the original and was stock internally, and I didn't rev it near as high, but back then I didn't care if it blew up anyways, it was near the end of the season and I wanted to get on to a 3.5 swap, and it had a lot of miles on it. But then some things happened and financially I wasn't able to do that swap this year like planned so instead I threw the DEK engine in, intending just to finish this season off with it, as it was cheap. The valve train stuff I put in the heads will all transfer over to the 3.5 with low miles/minimal wear otherwise I wouldn't have bothered doing that, I just would have used stock DE/DEK cams or at most stock 3.5 cams.

I'll be honest, I didn't want to spend the time and money on the 3.0 (ie on the bottom end, or on anything more than what would transfer to the 3.5). I felt the rods would be fine and so I took the chance the revup oil pump would live. Careless? Unwise? I can accept that criticism, and it was a risk no doubt, but as I said, I wasn't originally intending anything more for the engine other than a just a stop gap to finish this season. I never intended to fully build a proper 3.0, so all I did was install a cut-off switch to save the engine if the pump blew, and the switch did what it was supposed to. AFAIK at this point, the engine is fine.

But what happened along the way, and what I'm a bit regretful about now, is that after I got the engine up and running, I realized there's a lot more to be had out of this engine than I first thought/believed. Which seduced me into pushing it more than I should have, which also in some ways now tempts me to keep going with it to see where that limit is. But to do that, I see now that I'll have to spend the time/money to take care of the bottom end, which really I should have done in the first place then if that was my goal, but it wasn't.

I'm not sure I want to bother with the 3.0 anymore. I kind of lost focus on the 3.5 plans, and got caught up in the "what if?" with the 3.0 the last few months. But the major part of me is really just wanting to get on to the 3.5 swap I had originally intended to do. However, I'm also finding it tough/sad to walk away from the 3.0 now, knowing I'm leaving a lot on the table. Decisions, decisions.

Anyways, there you have the story. There was at least a little method to the madness.. lol. I guess the moral is: pick a goal/plan and stick to it, rather than trying to make a gelding snort like a stallion.

DandyMax

iTrader: (7)

Yeah, after thinking more about it on the weekend, looking at the pan, remembering that those 3.5 builds were balanced etc, I came to the conclusion it's not a flow issue. Furthermore, looking back on it now I must admit that I did think about the torsional vibration/balancing issues months ago before I put the engine together, discussed it with some friends locally etc at the time also, but wasn't sure how bad it would be, thought maybe I could get away with it.

In the end I made a decision to take the chance, which now I have to live with (see my reply to Matt above). Along the way, my gut has told me this would be the most likely cause, but sometimes the head needs to catch up, and I really need to learn to listen to my gut more instead of ignoring it and talking myself into other opinions.

I bought into the theory it was just a weak 3.0 pump and that the revup version would be stronger. But again, I must admit that when I took the revup pump apart before installing it I felt it wouldn't be much stronger, just flow more, but I continued to ignore my gut and took the chance it would survive, based on the fact I just wanted to do a "stop-gap 3.0" as cheaply as possible and get it running quickly. In the end my perfectionist/competitive nature meant that I just couldn't resist pushing the limit, even if it wasn't wise (I kept upping the self-imposed rev limit lol). Some of us need to learn the hard way I guess.

One thing is for sure, I wouldn't have/won't be cheaping out with the 3.5 though. That's the whole reason I delayed it in the first place, because I didn't have the money a year ago to do it properly like I wanted to.

Dave B

Ugggghhhhh.....

Yes, every late model engine you'll come across has an internally balanced assembly. Most every late model engine also has a crank pulley damper too. The design is usually two pullies fused together with an elastomer ring which performs the duty of a damper. When those pistons start firing, all sorts of 1st and 2nd order vibrations occur across the crank and those vibrations will change at various rpms and the internally balanced assembly is not worth much in this load situations. The crank damper quells these vibrations. On the other end of the crank resides either a torque converter or a flywheel. Both these devices serve as crank dampers too. Install a pulley without a damper and you'll risk wrecking the motor. The crank might be able to handle it, but other parts of the motor may not.

I strongly suggest on his next build he goes with something like a Fluidamper. It might suck out 2-3whp, but it's design far surpasses that of the stock damper and especially those POS UDPs.

Kevlo911

iTrader: (36)

http://www.importperformanceparts.ne...ps_nissan.html

What about those?

nismology

iTrader: (8)

Please to be explaining, then, all the 8000+ RPM reliable built VQ's that are NOT using a fluidampr. I can, but I'll wait for your version.

dfownz

iTrader: (5)

Real crappy news about the pump. Luckily you have all these guys to help you out.

I love to just kick back and read these threads!!!!!

DandyMax

iTrader: (7)

I really should re-iterate that I haven't confirmed that the pump went, it's just my preliminary diagnosis, although there's a high chance of it.

If indeed the pump went I think it's a balancing issue primarily.

I'm the first to admit I pushed the 3.0 farther than I should have, even though I knew better, but that's partly why I installed the cut-off switch to save the engine.

Anyhoo, I have a solid plan in place for my now-in-progress 3.5 build, that project's going to get pretty interesting and will be lots of work.

t6378tp

iTrader: (69)

so does that mean jime will no longer be the fastest n/a maxima on the org

Tatanko

iTrader: (34)

You planning on having a running 3.0 again at all? It's a shame. I think with your current 3.0 you could have gone mid 12's at least.

DandyMax

iTrader: (7)

I never said I wouldn't run the 3.0 again... ... in fact the engine still runs (not that I'd want to keep it on though, haha...)

I just said I'm working on a 3.5 now... two different things, that can co-exist to some degree... for now at least... until it gets to a certain point...

Tatanko

iTrader: (34)

Ahhh that's good news. Mid 12's?