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1969honda

Midnight Madness 560z...

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Running a q45 diff in my 240z now. Dyno at 600/600 tq. I was running 3.78 LSD long nose 300zx diff. Held the power just fine.. Ran the heck out of it at Sebring and Daytona. But wanted a 3.54 ratio.. R230 is slightly larger than the ford 9"... Don't need one of those unless your putting down serious power. Your z will be super fun with that kind of power

Edited by redleg

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The advantage of the Ford 8.8 is that it has a very good, and affordable gear selection, and it is also a lot lighter than an R230. I believe it's actually just a few pounds heavier than an R180. Personally I'd go for the Ford diff over any of the Nissan diffs.

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I didn't know it was that light, maybe I'll have to look into Will's setup a little more when I get to that point. I've been going the direction of throwing an s13/j30 subframe in due to how readily available and cheap they are; but if there is a weight savings and power threshold increase I will have to save my pennies and do some additional research.

Edited by 1969honda

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Well still no real progress on the body or engine, did fix some picture links that got messed up though from the first page.  I've also started to think about just rebuilding the engine with stock internals and getting it running and together before I commit any further to a forged rotating assembly and the ITB or supercharger.

 

There's been some interesting ideas brought by VK Nation on facebook using the 06+ fx45 front exit intake manifold that looks really interesting and close enough to stock to use without major changes to the fuel system or anything else.  It's got a designed in dual intake runner profile using a vacuum actuated set of butterflies that opens at higher rpms but closes at low rpms changing the intake tract from long on the low side and short on the higher end.  It's pretty interesting, and I can get a manifold for under 300 with the injectors, actuator and other necessary bolt on bits.

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Well I got some good news yesterday on the crankshaft and then this showed up in my e-mail today, should be shipping out with bearings as I write this!

 

Crankshaft_Polishing_zpsqrsi9mlc.jpg

 

Very excited to get this piece so that I can double check some measurements and make a final decision on rods (most likely Molnar Tech. LS Turbos, possibly Callies) and then decide on the final piston bore.  Need to contact Ray Shake from MA Motorsports and pick his brain on some different parts and the pistons I'm looking at....

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So I've e-mailed Nick at 5523 Motorsports a few times discussing my options on pistons and rods over the past month or so, also spent time double checking my crank journal diameters for peace of mind.  The rod journals are perfect at 2.0999-2.1000 on every journal, the mains appear to be 2.5165 which seems off, need to get a more accurate micrometer/caliper to check these as Nissan is spec'd at .001mm or .0001 in and my current tools only go down to .01mm or .0005in.  

 

On a good note though I spent a considerable amount of time measuring one bank of the engine (RH side, even cylinders) as I couldn't find my paper with previous measurements and along the depth of the bore my biggest variance is .03mm on two of the cylinders, one of which is the #4 hole that had the spun bearing, no surprises there.  As far as out of round my biggest difference has been .02mm for 98.02 to 98.04 so I think at this point it is getting pretty safe to say that somem standard bore forged pistons should work nicely.  Coincidentally ImportPerformanceParts.net is showing and overstock sale on Wiseco VK56DE standard bore 10:1 pistons right now....

 

Just have to decide if having a custom piston made is worth the cost or pay for some BCrower forged rods at about the same price as what pistons to fit off the shelf Chevy LS rod lengths will cost.  I'm either about $750 for the wiseco pistons and another 850 for forged BC rods, or I've had a quote for about $800 for custom pistons to suit the CH of using a longer LS off the shelf rod at $400-600 a set depending on rod bolts and length.  Leaning more towards the custom pistons and a Molnar Technologies 6.125 or 6.200 rod for a little higher rod to stroke ratio at the moment. Guess the wallet and time will only tell.

/bore%20measurements_zpshmbv5wbu.jpg

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I haven't checked JE yet, Racetec was about the same as Wiseco, CP was $1650.

 

Car is currently it side under a tarp, but the engine is in the garage. Did some research and cylinder liners are only 2.6mm thick, so I'm going to try to stay standard 98mm. Very tempted to pick up an m122 as they are around $300 now that TVS are becoming more available. There was a stage 2 ported unit on KSL last week for $250....

 

Whenever you want to come by just let me know, I don't work Fridays and am usually home every night after about 5

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Well progress isn't totally dead, I scored a good deal on a flex plate with the accompanying ring gear and crankshaft spacer.  Other than that I've been out of the country for a little while and just got home so progress was stopped during that time frame.

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Small update, had a deal on a 2015 0 mile take out 8.8" 3.15:1 tracloc fall in my lap last week thanks to JPNDave. So I've order a rear hub assembly to model in solidworks.

 

Dave also was gracious enough to bring over an inside micrometer Friday and let me double check my cylinder bore measurements has I wasn't comfortable with the T Gauge and micrometer I had used previously. Looks like all of my cylinders are 3.8590 - 3.8595" with no hourglassing or Distortion detected in any of the cylinders.

 

Armed with that information I contacted Tom Molnar about pricing for narrowing the big end of some Chevy LS Turbo Tuff rods he has and fitting them with a 22 millimeter wrist pin similar to the Nissan stock pin. I also got the je piston quote put together again for a 3.860 bore and will be sending off a quote to them as will be calling them to discuss options for naturally aspirated and supercharged.

Edited by 1969honda

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It was cool checking out your project. Always great when the parts measure out correct! I have a set of Manley H-Beams here as well as stock Gen 4 rods if you want to check them out.

 

These photos belong over here now...

post-31627-0-52606100-1464622188_thumb.jpg

post-31627-0-99687600-1464622196_thumb.jpg

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Thanks for the photos! Do you know what the offset it for the wheels you want to run yet? Just curious as I know that the z31 front hubs will bolt up to stock 240z spindles but create the need for a more positive offset rim.  Might actually work in my favor by the time the rear end is squared away and the new diff and axles installed.  Just thinking out loud here, double a-arms would be awesome but I'm still mulling over the additional time and expense versus running the front steering and suspension as is for now with coil overs.

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I had a set picked out but after more research may need more offset to really get the KPI/SAI right with zero dynamic scrub. I'll need to get my math closer to finalized before settling on the wheels. I had to do similar on that Jeep and it was a lot less complicated suspension! I'm planning on 18" staggered set hopefully a lightweight 5 spoke or paired 5 spoke. Cost for the wheels needs to stay out of the stratosphere too.

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If we can get the wheel bolt surface to center of KPI down to about 3" those wheels will work. Not sure that even makes sense. The stock strut will be more forgiving with a steeper angle but sacrifices in other places.

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