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Gollum

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Gollum last won the day on November 21 2023

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  • Birthday 07/07/1987

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  1. I'll be curious to see how these new projects pan out for them. I know the S30 market in Japan has gotten to be American-Mustang levels of insanity, with six figures being the norm for what a clean restoration can go for. But where does "purity" end with those builders and buyers? Is it perfectly fine to do a twin cam head when it's 4x the cost? Will they see any return on value for that? Will commissioning customers be interesting and foot the bill? Will they sell enough to be worth while? I have a feeling they won't come close to approaching the value Derek has, but I also wonder how many potential buyers there would be if someone like JCM just simply imported castings and finished them. Either way, more product options on the market are generally good, and tend to help the community as a whole. So, yay!
  2. I took the time and got the reverse alignment info here for posterity. An engine should sit about 1" towards the passenger measuring at the steering rack. If your engine sits further forward you might want the crank snout a bit proud of a inch left (looking towards the rear) and if your engine is super short maybe a hair shy of an inch. The larger point though is that if you perfectly center the engine in the engine bay, and point your transmission at the pinion exactly in line with the centerline of the pinion, you'll actually be introducing non-parallelism between the engine and transmission centerlines. If you add that on top of any unmatched angle between your engine tilt back/down and the pinion tilt up. The diff sits about 5 degrees nose up to begin with, so if you mount your engine level, it's not just the 5 degrees of difference you've added (which is a lot) but also likely some horizontal angle difference as well. Did several tests and measurements to ensure this was square: And then measured both directions from the steering rack bushings (could also easily see the offset from above)
  3. Before the last time I pulled the engine I was getting an idea for how aligned I was and square to the pinion centerline and chassis. Its "easy" to get your transmission aiming at the diff center, but that doesn't mean the diff would be pointing at a centerline that intersects the crank snout. So I measured the transmission output and the engine front as square to the rockers as a ball park idea to make sure I wasn't too far away from where I wanted to be. My results: Probably not perfect measurement methods, but I was surprised how close it all seemed to be without much fuss. Will measure it all again as I get ready to tack mounts.
  4. The good news about running a bit more engine angle and getting the engine up higher and all the way back, is that I can move the engine mount attachment points on the chassis side down and away from the top side of the frame rail box. So I cut off the tack welds and I'm making new sections to attach down on the side of the frame rail box and the TC rod attachment point. Once the mounts or made and I'm ready to weld these fully I'll box them in in a few areas.
  5. (2) Shirts Color: Black Size: Large (1) Hoodie Color: Black Size: XL Zip: 03070
  6. More fiddling, I think I'm going to actually end up with the engine tail down around 3 degrees. Everything just ends up fitting better. I can't get the engine as slammed back, but I can run it higher up (solving not just pan, but also exhaust clearance issues). It had been a while since I'd refreshed my memory, but my pinion is sitting at 4.6 degrees nose up already. I planned on making an RT style mount, but seeing that again highlighted just how important that will be in order to keep angles in check. I'm sure engine down 3, diff up 4.6 wouldn't be a huge deal on cruise, but we all know how much the nose of the diff wants to rise under accel, and that's a level that's getting to be concerning. So I'll add that to the endless todo list.
  7. I think a bit part of the problem with detonation on L heads is that the overall chamber is "lazy" compared to any modern chamber. There's virtually zero swirl going on. The spark plug is not ideally placed. The pistons aren't do anything to "help" either. Even if you used flap top pistons for added quench, you're still just putting band aids on upstream problems. And I'm not knocking 2V head designs. But look at how far GM has come: That chamber is just cleaned up, not worked. Note the plug angle. Note that it's quenching on both sides and that they're "pointing" different directions. There's also very little valve shrouding. Also, find me an EFI engine designed from scratch in the last 3 decades with round intake ports (to a single valve). Also, what are the average valve angles? Nissan more than once chose valve angles wider than they should have, and only realized it in hindsight. And engines like the L series which were initially carbureted and converted to EFI suffer from old assumptions. By using oval or other elongated entries you're encouraging the airflow to maintain better velocity averages across the lift and RPM range, and promotes swirl to excite atomization. Injectors are also worlds better than they used to be. If you pay attention, most people who de-cap injectors to get more flow might be able to make more power, but idle and cruise quality suffers. Ben talked about some great stuff in this podcast, and it's well worth the listen: https://www.hpacademy.com/blog/089-pushing-the-limits-of-nissans-forgotten-turbo-4-cylinder-podcast/ But something to ponder that he brings up, is that on meth they were running down to lamba 0.50 in order to keep the engine from detonating, that's gasoline equivalent of 7.3:1 btw... Absolutely insane amounts of fuel, and adding intercooling capacity wasn't helpful, and in some cases detrimental as they had an _even harder time_ atomizing fuel when there was less heat in the charge. And this is with the measurably better FJ head which had a lot more Nissan engineering prowess behind it's inception. So to think we're going to magically get a L series head to not fight detonation with some magic bullet? Nope. It's the reality we live with. We can do what we can to make the results predictable and live within those confines. I would say definitely add a huge intercooler, as a rule. If you're going to push past the 300whp mark, definitely do the head cooling mod. If you've ever got the head off, do Jeff's block/head cooling upgrades and use his head gasket. If I was still playing with L engines, I would also definitely go with an electric water pump, and probably reverse flow the engine. I would also never run non-premium pump gas, and ideally would just run E85 all the time. I had a MN47 with the intentions of making "high compression" turbo engine and doing all the above and more. But time and life lead me down different paths. The L engine can do amazing things if you put in the time and energy. But in a factory arrangement, you're almost always going to be fighting detonation as you raise the boost. Also, side note. I'd ditch the distributor/dizzy as anything other than an oil pump and potentially a cam sync. Put a wheel directly on the crank and you'll get FAR better timing accuracy. Even if your shaft has near-perfect lash (which any old used shaft won't) then you still have shaft flex/vibration issues to deal with, and your timing could be as much as 3 degrees off just from deflection. In my case with the added lash I was getting as much as a 8 degree timing error. Great way to grenade an engine.
  8. @AydinZ71 And I'm perfectly content to agree to disagree. My experience and point is that HEAT is what destroys rings, and that inlet temperatures have almost zero bearing on heat produced in combustion. The normal factory combustion within the engine at factory boost is going to be somewhere in the neighborhood of 800-1200C at point of ignition. Exhaust gasses once COOLED OFF during the power stroke will still be well over 400F at the manifold. Being concerned about 100F inlet or 160F inlet is irrelevant compared to these temperatures. That's my point. Now, if your lack of IC is causing you to be on the edge of detonation and getting into some sporadic light detonation here and there, I can see that eating through rings quickly too. The guys out there running 2k+HP on meth powered big blocks still chew through rings like a consumable, and their inlet temps at the valve itself are likely well below ambient. Inlet temps are only a small fraction of overall heat generated within the chamber and thus expanding the rings and causing them to work.
  9. First thing to set straight here is that lack of IC might lead to being harder on piston rings. This simply isn't true. Yes heat is what will kill your rings, and without enough ring gap then heating up the rings enough to the point of them touching will crack a ring land on the piston, just about every time (true for all engines, not just L engines). But that will be caused by BMEP over time far more than inlet temps. Heat produced is going to be a product of how much fuel is burned. Cold air makes for denser air makes for more fuel makes for more heat generation. An extra 3psi of air (at valve) will cause far more BMEP than 50 extra degrees fahrenheit on the inlet air. All THAT said the largest problem with hot air and raising the boost to the limits of the factory turbo, is that you WILL be seeing inlet temps over 200 degrees (been there, done it). At those temps your MBT or required timing is going to be a VERY narrow window. Retard the timing to be "safe" you'll be leaving a lot of power on the table. Be too aggressive and detonation is almost guaranteed since the mixture is so volatile. The factory compression is low, but the head is also super inefficient at mixing the charge, so you'll be bound to have rich and lean spots within each chamber, and running under load with that hot of air long enough, get heat soaked into that head and it will be detonation prone. So, if you want to spend a full day on a dyno with someone who knows what they're doing, you can likely get well over 200whp without an intercooler. But the tuning would have to be exact, and you'll only see that power figure on a cold run. If it's tuned well then each sequential run as it gets hotter and hotter the peak power will go down as inlet temps rise. Run an intercooler, or run E85. Or run both. Both take work. And if you want "bolt on" parts, I hate to say it: buy a different car. Any car that's outside of mainstream is going to take a good bit of work to modify. Personally, I'd go with a generic intercooler and generic piping kit. Get a larger same side in/out to make routing easier inside the engine bay, and while you're at it make sure the inlet to the turbo is in front of the radiator outside the engine bay like factory. It's worth it. If you upgrade your rubber fuel lines, injectors and pump to run E85 you'll have all the cooling you'll need to reach the limits of the factory bottom end if you put enough turbo on it. Hope that helps.
  10. Didn't snap pictures, but got the engine back in again after some firewall massaging and it's definitely sitting a bit better. I still feels like I'm hitting somewhere and it's not quite sitting where I want, but it's close. Also opened up the shifter opening width a touch which will definitely be required to fit the MGW shifter.
  11. I'd be interested in a black hoodie if we make a run. Also, if it saves effort I think Nick might still have a vector drawing of the logo around, which he drew up for the Norcal BBQ back in 2008. I'm digging around on my fileserver to see if I have a copy of the file, but I'm not sure he ever sent it to me as he was doing the shirt prints on his own.
  12. This is about as level as I can hope for, measuring several points around the car, I think the car is about 0.5 degrees tail up, so I'm probably within half a degree difference between the engine angle and the chassis. Positioning isn't perfectly square, and I'd like this to go back another 1/2", but it's close: Will definitely clear the hood at this height. Next time I'm out in the garage (hopefully tonight) I'm going to swap the sump support with another scissor jack so I can get a bit more precise on the height. Might weld some extra supports on a jack to give it a larger footprint and be less tippy (will still shim with wood for softness but would like it to not want to lean more than a few degrees. In this position, The shifter would just barely make it into the OEM opening, but definitely sticking up a bit proud. Overall this is definitely close to where it needs to be, but I would prefer being up another half inch or so, and another half inch back, but I think I might already be making contact in the tunnel somewhere. Going to investigate that, along with looking at what exhaust manifold clearance looks like in this spot.
  13. Tim is a legend. I wish I could hand him a 10k check for _all the carbon_ for my car, but sadly I'm just not there yet. Maybe some day. There's quite a few people on the facebook groups with some of his carbon parts. Seems to be a much better parts distributor/manufacture experience than some others have dealt with in the Z community.
  14. Oh, also potentially of interest, I don't see my having mentioned it before. I did this weight almost a dozen times, and this was the heaviest reading. If I had to guess, I think on an accurate crane setup (easier to omit balancing issues), I think actual weight would come in around 123lbs. Considering what a T56 weighs, and that these are "generally" okay up to 500whp, and still shift decently up to around 7k, it's not a bad "little" transmission. A pretty good weight-conscious way to get into a 6 speed transmission. In a perfect world, I'd love to have a TKX 5 speed, as they shift great at high RPM, and are fairly bullet proof, and have some really great ratio options. But for what I paid, and that this thing was less than 2 years old with less than 30k miles on it... I'm not upset.
  15. It looks like the pictures died... again. No idea what's going on. Here's the bushing I'm using (attached). I probably could have gone with smaller bushings for the transmission mount but it seemed to make sense to just make four of the same due to challenges finding the appropriate interference fit. These seem to work out nicely, so I figured I'll continue with them, despite being oversized for the trans,
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