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Gollum's Never Ending 280Z


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Definitely more foraging than forging. I'm not regretting having megasquirt, but I'd definitely make a different choice the second time around.

 

That said, today was a pretty product low key garage day. I now have my flex fuel sensor installed though my wiring isn't final (just wanted to make sure it works). Also got my new IAT bung welded on. Tomorrow I think I'm going to make a run to the parts store so I can sort out my vacuum lines a bit better, as well as maybe find some steel tube to allow me to add my new bypass valve. I also spent some time working on my accel enrichment curve and now it's much more responsive with throttle stabs. Not perfect, but I need my VE table to be more solid before I fuss much more. And in case you didn't see it elsewhere: 

 

 

I was thinking I'd just cut the whole thing out, but I don't want to grind around down there too much with the tank in place, but then I realized I can just drill out the spot welds. Might tackle that tomorrow. We'll see. I know eventually, possibly next winter, I'll be installing a fuel cell so anything I do now is just temporary until I have a final floor placement with a cell in place.

 

 

A small side note: Though goof off is primarily acetone, it's definitely FAR better at removing dynamat TAR. By a lot. It's also only $2/gal more at my local Lowes.

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  • 4 weeks later...
  • 4 weeks later...

Progress continues on. Oil AND fuel pressure are wired in now, so I'm officially down to once ADC left on MS3X.

 

Been working on a racepak inspired dash.

Screenshot_20190314-170122.thumb.png.28ce888f59d78c8cfbbac549b59f533f.png

 

Otherwise been putting miles on the car as much as I can.

 

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  • 5 months later...

As some know, I blew a mechanical fuse (headgasket) tuning which didn't bother me too much. But after several conversations I realized that I should probably do a thorough clean out of the coolant system, as there was likely good amounts of scale in the block and likely didn't help detonation problems. So I went ahead and pulled the motor and cleaned it out, put in new (steel) core plugs. I also wanted to replace my oil pan gasket while I had it out because I knew it was at least one of my main leaks.

 

I was cleaning the pan out, and found:

 

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Yup, those are piston skirts...

 

How long have they been in there? Who knows. Could have been like that when I bought the car for all I know.

 

Do they even belong to an installed piston? Yup. #5.

 

Was that the cylinder that blew the gasket? Nope. That was between 3 and 4.

 

All this while I'm trying to get ready for an AutoX event in just under a month. Luckily it sounds like @stupid_fast will be hauling a motor over for my use in the meantime. I'll owe him big time. Then I need to figure out what I'll do about this motor. I'll need to call around and see what machine shop I should use and what it'll cost to get it cleaned, decked, and matched to a new set of pistons. I really don't want to spend $3k building a motor, but I also don't want to throw away money on something that won't be reliable for my goals (which are relatively mild). On the plus side, maybe I should be putting in an order with JeffP for a head gasket and doing his block modifications while I'm at it.

 

Then there's STILL the chance I might take the block to a shop, just to find out it's not a candidate for keeping due to wall thickness. I know Jeff went through several blocks before finding a "good one".

 

These are times that it's dangerous to have my lack of purity. F22C's start looking cheap. Or VQ's... Or LSx's....

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So I have a spare motor on it's way over to me thanks to stupid_fast who's really coming through for me. In the meantime, nodus is scheeming and causing all sorts of trouble (the good kind). He has a project that's likely getting parted out, so there's a motor there that will likely end up at my house. More to come later.

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No reason to go forged pistons unless you're just trying to save weight. The factory pistons break because of detonation, not power generated. Forged pistons can give you a bit more wiggle room in that they'll take the abuse of mild detonation, but that abuse is just transferred to everything else. The real answer is to tune it to not detonate, which is also why I went with a gasket I knew would blow easily. If the tune is solid, there's no reason you can't make 400+whp on a factory long block. You'll have heat issues trying to hold that power for long intervals, but for drag racing it should hold up fine. I'd say anything above 350whp will have heat management issues on a road course and you should be doing the same things Jeff is doing to his block and head to improve coolant flow. But even then, forged pistons are still not needed. If you're building a 200+whp NA build though, you'll want lightweight pistons, which means go with something for weight reasons, not strength/power reasons.

 

That said, I've had to do much soul searching. I'm extremely unbiased and love to see any swap into a S30. I wanted the L28ET because it would supply enough power for my goals and is economical compared to any swap. The problem is my opinion on that matter has aged. I've been on these forums and into Z cars for 16+ years now. The market has changed. I can't just go find another L28 core all day long in the junkyards. I can't find turbo donors for under $1,000 regularly.

 

If I'm going to be racing regularly (autox for now, hpde in the future) I don't want to be worried about the issues with anytime I have motor issues. I need a mill that isn't just dependable, but expendable. That second factor is really where the L engine is lacking.

 

So I'm putting in a spare L28ET for now, but there's a good chance it's coming out come winter with something else going in.

 

In the same vein, any suspension mods I'll be doing will also be as "off the shelf" as possible. There often over looked value of being able to get bushings, bearings, bolts, etc at your nearest parts store and not wait for something to show up online. If you look at parts used for circle track this is very much the way everyone builds their cars. You fabricate the chassis around common parts, not the other way around. I'm not interested in making or buying custom parts because they fit my chassis. I'm interested in making my vehicle fixable/repairable when things go wrong. And there's always something that'll be going wrong.

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I know what your saying, but forgiveness is the reason to switch. How much is your time worth when swapping and dissembling engines?   As you’ve noticed, sometimes a head gasket won’t be the weakest fuse.  Not meaning to argue, just explaining why I question it.

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And how many built engines did Jeff go through before finally deciding to tune on a junkyard oem combo? And then he ended up making more power on that motor than most, go figure. ;-)

 

My point is that even forged pistons aren't going to give you enough forgiveness to "learn to tune" on. Don't waste money when you don't have to. If this were still the year 2002 I'd say there's absolutely no reason to go forged pistons for me and my use case. But with today's supply of L engines, you have a bit of a point.

 

But at what cost? At minimum I'd end up with:

$500-700 in machine work minimum to get the block sonic tested, bored, decked, coolant ports opened, and studs upsized.

$1,000 for forged pistons, though maybe you know of a deal I don't for a nice piston that fits the factory rods

$100-200 in all the rebuild odds and ends

$700-800 for a proper damper and trigger wheel (which is half of my detonation problem, thus needs to be done)

If I'm doing all that, I might as well tack on:

$250 head machine work to clean the deck and open the valve seat for larger valves

$500 for larger valves

My time and energy to clean up the valve seat backside radius, bowl, and port cheeks.

$500 Camshaft

$200 valve springs

$150 New rockers

$100 Lash pads

And probably other things I'm forgetting.

 

In all reality, investing ANY parts into an L engine starts to make you ask "where to stop" because rebuilding a motor to only do a basic bore cleanup by a machinist and slapping in forged pistons doesn't sound like a wise investment. You either go all the way, or not at all. I was a huge fan of the "not at all" approach. The issue is the supplies as of late.

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DSC_0829.thumb.JPG.308d9253d9c15a1d6eb7bb5dde59128f.JPG

Other than a bit of a mishap installing the rear main seal, Gollum's  new loaner motor ready to go.  I dropped it off earlier today.


Came out of a 240z in running condition that my buddies doing a v8 swap on.  Had a pair of SU's and a points dizzy on it!  To my surprise it was a P90/F54. 

Put front & rear seals and replaced the valve stem seals, installed an A cam and a newer OSK timing sprocket from my engine while I was at it. 
Looks like a clean original turbo motor, but there is evidence the timing chain has been changed at some point. 
Should be a good runner for Gollum to get some seat time while he collects parts for his swap. 

 

Edited by stupid_fast
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New motor arrived (thanks stupid_fast!) along with a baller clutch alignment tool. 😀

 

image.thumb.png.a2c573072367291d6aa75c1cea518e88.png

 

Will try my best to get the motor buttoned up and back in the car by Thursday. Going camping for the long weekend, and will then have next week and weekend to get her fired up and rolling around again.

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Got the engine in Tuesday. Likely won't get it fired up tonight, so next Tuesday is the most likely time I'll get to play around on it some more. If all goes well, I'll be driving it next weekend checking the tune on this motor combo (different head/cam/compression).

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21 hours ago, Gollum said:

Got the engine in Tuesday. Likely won't get it fired up tonight, so next Tuesday is the most likely time I'll get to play around on it some more. If all goes well, I'll be driving it next weekend checking the tune on this motor combo (different head/cam/compression).

 

Sweet, good work!

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  • 3 weeks later...

So the autox event was fantastic. Definitely worth every penny. $75 for the event and I think I got about 15-20 runs in. Pretty cheap seat time.

 

image.thumb.png.b7af59b3e7563a614c075e8b19adabfd.png

 

The big win of the day was simply that nothing broke. I had my AAA card on the ready just in case, but the car worked splendidly. I have a slow temp creep but only when sitting at idle. Temps were actually lower after a run than before. Most of the day the pace was just slow enough that I'd shut down while waiting to stage and temps stayed under control. Towards the end of the day as people left early the pace was a little fast for my radiator/fan arrangement so I just took some extra time and let a few people pass through ahead of me. No biggie.

 

And since I'm going to be ripping a bunch of stuff out anyway, why just solve the problem, when you can solve the problem while creating extra work?

 

image.thumb.png.89adf5c123abcf4555c85434235be198.png

 

Extra points for anyone that can guess the donor car for the radiator. Here's a hint, I'm putting the engine in too.

 

It's way too wide at it's widest point, but that's nothing a cut off wheel and a welder can't fix.

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  • Gollum changed the title to Gollum's Never Ending 280Z

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