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Jay's 72 S30

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I was able to get some more work done today. Removed the vavles and cleaned everything up a little bit more. Turbo blanket came in, checked fitment. 



The seats arent too bad but I'm glad I decided to lap them. 


You can definitely see where the room for improvement is in the bowls. 


Nice and clean, ready to port though my bits arent here yet so thats going to have to wait I guess... 


I have the alum retainers from the bre cam kit and a brand new set of nismo ones. I am torn on which to use, seems like a waste to use the brand new nismo ones lol. 


So tomorrow I'm going to do some parts cleaning, painting, wrapping and if I find local bits I'll start porting. 

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WHOAH ! That old school turbo setup looks REALLY neat , and +5 points for unique/sweetness !

Big grin on my face...... followed by a steady grin for at least the last few minutes while updating myself to your thread !!!


The head inspection , cleanup , and work looks great to me man :thumbup:.... (nice valve spring compressor !!)


... and also lucky you on the what looks to be the ...solid state....  of your latest engine picked up .... great cross-hatching :cool:


Keep up the great work Jay :cool: ... always have enjoyed this thread being bumped as stuff gets done !!! (unlike my threads lol)

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Thanks Blue :-)

Tons of stuff gets done on your threads you just have more of them lol. Matter of fact your thread is what motivated me to actually do head work. My original plan was to just try and slap this together before I leave for Japan in April. 

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Got some more work done before I leave again for work. 
Broke down the whole kit because after finding some sketch stuff I just didnt trust it. 

Right off the bad found some home owner nonsense. Using cork/rubber/permatex and smooshing it in really hurts flow so this is pretty bad.

This is what prompted me to break everything down and really check it all


Which after some prodding turned into this

The metal is so thin it was really hard to weld, I blew through in multiple areas and had to build it up and grind it down. This is the kind of exhaust that wrapping will destroy asap. I was planning on wrapping this area but after seeing this no way. Its a really shitty design too once I get the set up running the 1st order of business is to fab my own spool piece from the exhaust mani to the turbo. It will be easier once I fab a down pipe because I can unbolt just it and have everything else stay in place, then I wont have to make a jig. 

The oil return must have been leaking for a while judging by the staining. There was also a leak in the top left corner of the exhaust inlet. 

This is the ghetto way they had the throttle rigged up. I will fab something less obnoxious. 

I painted everything but didnt take a pic because I was pissed at all this stuff lol. Welding the exhaust was really a pain in the ass. 

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  • 2 weeks later...

:-) oh I will, I leave this coming Thursday, then back end of April. 

I finished up on the intake manifold. Painted, made gaskets, replaced the bolts with proper sized ones, Heat reflective tape and fabbed up black off plates for the cross over tube. Think its a drastic difference vs how I got it haha. 


Cleaned and painted the exhaust mani and extension. Added a thread sealant to the plugs. I dont know what it was about the previous owners of this set up, they really liked exhaust leaks...

Alum radiator came in, cant really complain about anything given how cheap they sell these things. Although my new stant cap sits at a 45 degree angle? Not sure why... 

Also started porting the head but am at a dead end waiting for the flexible extension I need to get deeper. I'll port pics once I make real progress on it. 
So I guess thats it for being able to work on the Z for a while. When I get back from Japan I'm going to be swamped at work for a while too :-/. When I do get the time I plan to get this in the Z ASAP. 

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Thanks Christine, so you will have your turbo done by the time I get back right? :-)

You coming out to Jersey again this year? 

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Thanks Christine, so you will have your turbo done by the time I get back right? :-)


You coming out to Jersey again this year?

Haha I doubt I'll be finished. You'll probably be back, finish up yours and drive 10,000 miles before I finish mine.


If my car isn't ready I'll still go, but as a passenger in the 370z. :(


We'll see how things work out, lol

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  • 4 weeks later...

Back from Japan I been trying to work through the jet lag and get shit done since once I go back to work it will be weeks until I can do anything. I'm hoping to get everything 100% ready to install so I can tear into the Z in 2 weeks when I'm back from work. 

I got the head ported finally after fixing my HF die grinder like 3 times lol. 

The ports are matched to the gasket but not manifold since I didnt port the manifold. This whole set up is just for fun and once I get the fever I figure I will prob fab my own manifold or do triple brow through or w/e so no sense taking the time to work the manifold and or match it. 
Lifted the ports and reduced the radii, deburred and smoothed the ports and transitions. Opened the ports up a good deal especially the cheeks but kept the throats moderate so port velocity stays up.

Did a lot of work in the bowls where the some of the biggest improvements are to be had on the L series heads. 

So intake manifold and exhaust manifold are back together and ready to do, turbo carb and adapter are ready to go. Head is assembled besides the cam, towers and spray bar which are still in the car. New valves and seals, low mile springs and alum retainers. 

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  • 1 month later...

Been a while with no update. I have been traveling for work and working to finish this swap with literally all my free time. 

A couple weeks ago I spent some time to fab a down pipe. What a Pita it is to fab when the car is in my garage and my power and welder is up the block at my apt. That means I have to fit a piece then go tack it then go back and check fitment then go back and weld it etc... for 6 welds lol. I came out pretty good though. Because of the turbos top mount placement there isnt much room to use 45s like a l28et.

Once together it started right up and with some adjustments idled fine. The car would fall on its face if you tried to do anything though. It would not boost at all and would flat out stall if you kept trying. With a friends help the dp was removed and we could see the turbo wasnt spinning at idle. Sometimes that normal but we also found there was no oil feed orifice and was afraid maybe the full pressure was locking the turbo up. To solve the problem I ordered a street 90 and taped the street side for a 1/16 plug. I then drilled the plug with a 2mm hole which seems to be the most common size for a turbo of this type. Not to pat myself on the back ut I thought it was a good solution lol. It also gave the soft line more slack, it was really tight without the L. 
So that didnt solve the problem. its good that its done though so whatever. 
In replicating the issue over and over I could see on the wide band it was leaning out off the charts. 1st I tried going from 145 to 230 jets and the problem was alomost the same. This time though when forcing the car to bog and kick it boosted just slightly for a moment then fall on its face again. No change on the gauge however. 
Here is a pic just to break up all this bs typing lol

Those were the biggest jet I had, so I drilled out to 350. Thats so big I would have never guessed to try and go there but you know what it improved. Again it would still fall flat if you dropped the throttle but it boosted to 7lbs and pulled well. Then I noticed the emulsion tubes were f16s, kind of in the middle as far as rich or lean. I was using F2's on my triples which are 2nd from the richest so I swapped those in along with larger air correctors and holy shit the car ran hard. It boosted to 11lb and slammed into 2nd like it was begging to break something. I also gave it some timing, 25 advance at idle. I also enriched the idle to 12:1. Those 2 things really helped the throttle response. It STILL wants to bog when you slam the gas pedal but you know triples do that too. Its just slight now and if you even rev it up slightly and dump the clutch to take off it doesnt do it. I will keep fine tuning more but I feel like that issue will never fully go away because both of those plates opening fully I cant imagine the fuel being sprayed and making it through the turbo with out some kind of initial lag. 
Another pic for fun 


So now it seems to be at least streetable. I need to get the hood on, do a good check and seal the fan tot he radiator because the car is overheating very easily. Once on the road I can fine tune and maybe start leaning out the top end a bit. Right now it goes rich as hell (10-11:1) but that could be either the jets too large or the fact I only have 230 air correctors in there and with 350 jets they should be more like 360 air correctors lol. Rich is safe though so I am going to take my time on tuning that aspect. 

I'm going to try and keep up to date on the tuning aspect because I have spent hours and hours researching and found little to nothing on this set up. No tuning advice, no baselines not shit. So let the next glutton for punishment find this when they search and at least gain and idea of where to be when tuning. Two of the biggest finds for help were actually corvair sites and Beat sites because both of them seem to love draw through set ups. The corvairs even have a guy modifying dcoes so that one throttle shaft will open like normal and the other will open with an actuator as needed by a vac/boost reference. That may be what they do to eliminate the initial bog when gunning the throttle. I may start researching that modification to see if I can do it myself. 

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Looking great Jay !!!

That last pic of your s30 looks killer man congrats !!! :hyper:

I'm impressed you got it all together , and working for you as soon as you did with work , travels , etc and the unique setup none the less.

Very cool on you man ! :cool:

Although..... I have an urge to take your carb , and push it in at 90-degrees ... back where it should be .... I'm just not use to seeing it like this kind of a setup... lol.


lol... I love those little harbor freight die grinder/carver flex shaft motor thingy's , and they can be used on quite a few things suprisingly which is cool !


I think trying to jet/tune your setup (in my thoughts) would have me on a nervous edge , but it's very apparent right off the bat you're more capable then I am or have been for some time .... lol ! :cool:

It's amazing to me (not suprisinging entirely.. if that's a better way to say ?) that you had to bump up the jets (drill) that far to get it within a closer operating safe rich parameter with your wide-band , and still working with the setup to where you feel it needs to be ! . Holy crap....11lbs of boost in an s30...... hory sheettt lololol .... you gonna need new tires man ???.... lololol  .... THAT'S AWESOME !!!! :hyper: :hyper: :hyper: ..... I'm just excited to hear/see this being done. It's not a project I would have taken on myself as I've been typically afraid of in the past of screwing up my engine whilst trying to dial/tune it in lolololol . Now that I see your workup......... it's more of an expression of "wow.................... :blink: :cool:"


That's an awesome piece of reference on the corvair guys research.

I wouldn't have thought about that at all without someone telling me for years ... lol :cool:.


I'm sure someone will thank you down the line for at least getting a beat or baseline of what's up to chew on at the VERY LEAST !!! :D



Always enjoy reading this thread you've spent a some well spent hours ,sweat , and blood getting this all to this point :cool:

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Yep really, I got my asking from a young guy down in NC. I have been doing nothing but Nissan/Datsun for a decade, its time for a change. 

I have to say though the NSX is the best car I have ever owned. The level of engineering and enjoyment is ridiculous. 

This weekend I rebadged it and converted to jdm tails I brought back with me my last time there. Also installed a Pride v2 exhaust. 


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