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Subject Twin to Single turbo conversion, FMIC coming soon!
     
Posted by ZLover4Life on November 23, 2009 at 1:31 AM
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Message Back in April or May, I fired up the TT for the first time of the year with the intent of prepping it for the first Z meet of the year. Started on five cylinders, which isn't uncommon for a car that sits (especially one still with early style injectors, which would've ruined my weekend on its own). In the hopes that I could get the sixth cylinder firing, I goosed the throttle. What I heard next could only be described as the sound that an unevenly mounted fan (or one mounted to a dead water pump) makes when it impacts the crank pulley... which was exactly what I thought happened. After inspecting the front end of the engine, I found no impact, so I tried goosing the throttle again. Same sound, then the car died. Tried cranking it, but the engine was apparently seized. I knew then that the head gasket had blown.

Rewind two years. Cylinder number two spun a bearing, badly. I pulled the engine, stripped it down, replaced the rod and bearings, and proceeded with reassembly. Upon torquing the driver's side cylinder head, I stripped the rear outer-most bolt hole. Ran a tap through it to clean out the threads, then a magnet through it to get the shards out, and tried again... same result. I could get the first torque sequence (10 ft-lbs or so) down, but any time I tried going to 80 ft-lbs (or whatever the spec is), it'd strip.

After 3 or 4 times putting the cylinder head on the engine, I was becoming concerned for the integrity of the head gasket, but I didn't have the means to source a new one, so I stuck with what I had. After ultimately using a helicoil because the threads were damaged beyond use, I realized the problem - I was trying to use the one shorter bolt on the wrong hole. After correcting that mistake and retorquing through the first and second sequence, I deemed it too risky to retorque that particular bolt the final time. I knew there'd be long term risk, but oh well. Two years later, the risk is realized (after dynoing 469rwhp the previous summer, I might add).

Back to the present year. The engine needs to be pulled, regardless of anything else, so I decided it was time to re-evaluate my plans with the car. The chassis was rusting, the rear subframe bushings were shot, the interior wasn't to my standards, and now the engine was in need of major work. I decided it was time to pull the engine and sell the chassis, figuring I'll eventually buy another Z32 to swap my mods into and the value of a non-running modded Z32 is crap anyway.

Within a couple days of posting the chassis, I'm offered a trade + cash, which brings me to my conversion... here's a couple pics of the conversion process...

But those educated in the car will say "you said single turbo conversion... that's not turbo!" to which I reply, it's been converted.

The trade I'm offered is a 1973 Datsun 240Z (83k on the chassis - it has sat in a garage for approximately the past two decades, untouched) with an incomplete L28ET swap (L28ET <- 280ZX). It "needs wiring and rear brakes," I'm told. Due to horrible scheduling conflicts (I live 250 miles from the car at the time), I take his word. July 12, 2009, the trade is completed.

And so it began... and was followed by a call to a friend familiar with the 280ZX turbo conversion. The harness went in smoothly, but we began noticing other problems... components of the harness that were seemingly cut for no reason, pieces that were missing... an ENTIRE carb fuel system that could not supply enough fuel for the hungry FI system... even little things like locks that didn't work. But surprisingly, when connected to power, EVERYTHING electronic worked just fine. Headlights, tail lights, interior lights, fans, etc.

It took a lot of reading and a lot of orders through Jegs and select other parts suppliers and various forum members to get the parts I needed. 3/8" high-pressure hardline, -8AN and -6AN fuel cell bulkhead fittings, fuel pump, fuel tank restoration kit, 1984 300ZX NA rear rotors, 1989 240SX rear calipers, intake filter, intake hardpipe, clamps and hoses galore, a strip of 1/4" aluminum to custom fabricate tank straps that are apparently impossible to find, a 2.5" downpipe, 1984 300ZX NA wheels, 1983 280ZX Turbo/Manual ECU, fluids, etc etc etc (I could make this list make the list of that eBay 300ZX that included things like "helicoils" as mods look typical). And it's still not road-worthy yet... that'll take front brakes, tires, and possibly suspension work. That's all ignoring the cosmetic work it desperately needs. But here it is... the car that has kept me as a Z owner since I got rid of the Z32 on July 12, 2009.

The road has been long... swapping out and fabricating an ENTIRE fuel system is not an easy task. Repairing and modifying a fuel tank, a 4-5 day process, is not for the impatient. Drilling and tapping almost every bolt hole because they are all seized is not for someone who is willing to punch a door panel in frustration. Sawzalling drum brake backing plates and modifying calipers for ~10" rotors to accept ~11.4" rotors, only to find out that now the stock wheels don't fit isn't for someone who gives up easily (hell, it even needed special lug nuts for the wheels I purchased). Fortunately, this car came under my ownership, and I have the love for Z's that this car required. And the knowledge I have gained from the experience has given me such a vastly different outlook on automotive modification. I once feared pulling a Z32 engine... I've done that at least six times, now. And after this, I feel there is no automotive task I could not tackle. Except my damn Blazer's 4WD system.

Video of the car running for the first day in about two decades

Excuse the harshness of the exhaust - not only has it sat for such a long time, but that's currently an open downpipe. Enjoy the turbo spool, though.

Thanks to:
Brad (bstyleZ), his father, and annonymous (for the car itself)
Eric (for his invaluable assistance)
Ron (for his insight into how to plumb the fuel tank)
Andy and Dave (for the spare parts)
and my father (for his incredible attention to detail and his willingness to help even without always understanding what needed to be done, as well as his ability to answer questions pertaining to how to use 1973 seat belts, 1973 vent controls, etc lol)

"When you say this, will you be surprised if your arguments seem to move about instead of staying put? And will you accuse me of being Daedalus who makes them move, though you are yourself much more skillful than Daedalus and make them go around in a circle? Or do you not realize that our argument has moved around and come again to the same place? [...] Or do you not remember?" - Socrates

     
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