DATSANITI - '80 210 Wagon VQ35 Swap

[]2eDeYe]

43 minutes ago, thisismatt said:

Yep. That's just a fuel damper. A good reason to also get the stock pump when you get the VQ.  Get the o-ring with it also, they're like $20+ from Nissan.  There are aftermarket kits/rails if you want to change to a traditional fuel return system. 

 

 

I will be taking the entire tank :)

 

[Maschinenbau]

Good idea, that's what I did too. A few pages back you will find the tank I custom built around the stock VQ pump/sender unit. It's all packaged in one piece. Just don't break the plastic barb fitting for the fuel supply, or you'll have to replace the whole thing again. Luckily this stuff is plentiful in junkyards right now and easy to access under the rear seat.

[metalmonkey47]

On 7/23/2019 at 8:59 PM, Maschinenbau said:

How many hose clamps in your fuel system is too many hose clamps in your fuel system? No leaks after tightening everything down and the engine still runs like normal. 

 

*ahem* we actually make a part for that. Can I donate one to you so you can get rid of that super sketch fuel tap?

https://www.z1motorsports.com/z1-products/z1-motorsports/z1-motorsports-vq-fuel-port-p-9160.html

 

Edited July 25, 2019 by metalmonkey47

[thisismatt]

1 hour ago, metalmonkey47 said:

*ahem* we actually make a part for that. Can I donate one to you so you can get rid of that super sketch fuel tap?

https://www.z1motorsports.com/z1-products/z1-motorsports/z1-motorsports-vq-fuel-port-p-9160.html

 

 That, with the gauge, is on my list of fuel related parts 😁 Ratsun discount?

[]2eDeYe]

On 7/24/2019 at 11:18 AM, Maschinenbau said:

Good idea, that's what I did too. A few pages back you will find the tank I custom built around the stock VQ pump/sender unit. It's all packaged in one piece. Just don't break the plastic barb fitting for the fuel supply, or you'll have to replace the whole thing again. Luckily this stuff is plentiful in junkyards right now and easy to access under the rear seat.

 

This thread is a treasure trove for me right now :)

Anything else you recommend keeping or just throwing away?

 

 

 

2 hours ago, metalmonkey47 said:

*ahem* we actually make a part for that. Can I donate one to you so you can get rid of that super sketch fuel tap?

https://www.z1motorsports.com/z1-products/z1-motorsports/z1-motorsports-vq-fuel-port-p-9160.html

 

 

 

How much is that bit? 

[Maschinenbau]

2 hours ago, metalmonkey47 said:

*ahem* we actually make a part for that. Can I donate one to you so you can get rid of that super sketch fuel tap?

https://www.z1motorsports.com/z1-products/z1-motorsports/z1-motorsports-vq-fuel-port-p-9160.html

 

 

I would love to be able to accept it, but the $2000 Challenge budget rules forbid gifts and other "free" parts. After the Challenge though, I will definitely be buying one if I continue to race and spray this car. I think it has 11s in it.

[Maschinenbau]

Sketchy $200 nitrous kit is installed and working. I'm going to the big boy drag strip tonight, which will be Datsaniti's furthest drive to date at 150 miles round trip. Coming home with either time slips, a list of ways to not fail tech, or a towing bill. One of the first two, preferably.

 

Feels good working with metal again. 

 

 

 

 

[Maschinenbau]

16 hours ago, ]2eDeYe said:

 

This thread is a treasure trove for me right now 🙂

Anything else you recommend keeping or just throwing away?

 

 

Try to get the entire wire harness and all computers from roughly front seats forward. Especially the ignition tumbler/antennae and key because it's all paired to the ECM for anti-theft. You can  get the ECM flashed (ahem Z1 ahem) to get rid of the antitheft, but better to have it all and not use it. Gauge cluster I think also needs to be connected to CAN. Basically open a G35 FSM and grab everything connected to the CAN network or it may not start. You can splice in the rest for the fuel system. 

[metalmonkey47]

17 hours ago, Maschinenbau said:

 

I would love to be able to accept it, but the $2000 Challenge budget rules forbid gifts and other "free" parts. After the Challenge though, I will definitely be buying one if I continue to race and spray this car. I think it has 11s in it.

Ahhh forgot about that. Let me know when you get to that point, I may be able to help you a little bit there.

 

17 hours ago, ]2eDeYe said:

How much is that bit? 

A whole $58 😂

 

18 hours ago, thisismatt said:

 That, with the gauge, is on my list of fuel related parts 😁 Ratsun discount?

Can probably manage something 😃

[Maschinenbau]

2 hours ago, metalmonkey47 said:

Ahhh forgot about that. Let me know when you get to that point, I may be able to help you a little bit there.

 

 

I'll put a big Z1 sticker on my car, if that helps. Though you probably don't want your name on such a junker LOL

[metalmonkey47]

4 hours ago, Maschinenbau said:

 

I'll put a big Z1 sticker on my car, if that helps. Though you probably don't want your name on such a junker LOL

 

psh that junker is badass 😂 seems like an even trade.

[Maschinenbau]

Summary of the night: Nitrous. Is. AWESOME.

 

Loaded up for the big road trip to the Atlanta Dragway. It took over 2 hours to go 75 miles thanks to Friday afternoon Atlanta traffic. This car sucks to drive in traffic. No A/C, not even a fan, no floor insulation, feet are hot, everything is hot, seat too stiff, loud raspy exhaust (ear plugs the whole way), fingers crossed that pot hole doesn't hit the oil pan, and a constant high-stress state of "what's THAT new sound??" But it did it. Coming back home around midnight was a much nicer drive, maybe even enjoyable.

 

 

Tech was pretty lax. Actually too relaxed, honestly. I was hoping to come home with a list of things I should do. They didn't even look under the hood at the sketchy fuel tee situation. They only had quibbles over the battery box, which I really should replace with a plastic sealed container instead of my crappy filing cabinet drawer. I'll fix the fuel situation anyway and read the NHRA rulebook again.

 

Forgot about an incident on the drive up. Right as I was getting off the interstate, the hood suddenly started "floating" up a couple inches. Uh oh. Part of the hood latch piece was expoxied back on after the hood gutting, and I guess that bond broke. The other half of the latch was welded from the factory, so it probably wouldn't have detached, but it's not a good look. Luckily another racer had a rivet kit. 

 

 

 

 

 

I'm honestly a little disappointed in the times. I was hoping for 13's all motor. According to some calculators, the motor is down compared to the advertised 260hp crank. For these ET's, MPH, and weight, that's roughly 175hp at the wheel and I'm not sure how much better I can get the 60' since the tires are hooking pretty well. Try to stall higher? Spray down low and cross my fingers?

 

...But a pig-rich 35?40? shot really cut that time down! I have bigger jets I'm itching to try, but I knew this would be a safe first-time spray. My goal from the start of this build has been 11's, but I'm not as optimistic after last night. Still, that was a ton of fun and I'm overall happy with how the car did tonight both on and off the track.

Fastest run crappy dashboard view

 

[]2eDeYe]

The autotragics in these really suck a bit of power I've noticed. 

[afracer]

I've seen nothing but overestimation on quarter mile times on guy's builds. Easiest way to run 11s is to build it to run 10s and accept that it'll probably never run 10s without thousands more in chassis, suspension, and tires and lots of tuning. My Datsun should be able to run 10s based on power to weight ratio but will never get there as it is. I'd be happy with low 12s honestly but there's no 1/4 mile tracks near me either. 

[Maschinenbau]

So true. There's always a lot of "bench racing" online but reality has too many variables to account for. Possibly overrated power of the VQ35DE (especially early sedan versions like mine), worn internals at over 150,000 miles, not stalling high enough at the tree, car could weigh more than expected, hot humid weather, maybe dragging a rear brake after the burnout? wheel, hub, and rotor were hot AF after each run, but cool on the drive home. You just never know. 

 

But I'm not here to make excuses. I'm here to go as fast as possible for under $2,000, have fun doing it, and share the experience and knowledge with you all as I go.

[bilzbobaggins]

This is awesome.  All this speed and style for under 2k.  Compare that to a buddy of mine who bought a cadillac ctsv, has dumped money into the supercharger and a e85 tune, and is not a whole lot faster than that in the quarter mile with much less style.

[metalmonkey47]

Even a tired autotragic on our dyno is usually around 220whp stock, if you're feeling that underpowered you have a problem somewhere. What's your exhaust situation? 2.5'' dual? Are you using the stock MAF housing?

I'd check for vacuum leaks between the upper and lower plenum as well, pretty common place to see a leak if the plenums have been separated.

Edited July 29, 2019 by metalmonkey47

[Maschinenbau]

Exhaust is stock manifolds to dual 2", Y-pipe into 2.5" through some no-name muffler. Possible leaks in the flexpipes from scraping (lowlife lol) but that's well downstream of the O2 sensors.

 

MAF and housing is stock, but the tube between MAF and throttle elbow is straight 3" PVC.

 

Any advice on the vacuum leak check? Follow the smoke? I don't think this intake has ever been off. 

 

Something stupid I realized yesterday may be the throttle pedal-stop keeping it from 100% WOT. I put the pedal-stop in to keep me from over-extending the pedal sensor after all the issues I had with the sensor (which now I think were just cleanliness related - dousing in contact cleaner seemed to fix it?). I'm going to borrow an OBD reader to verify if I'm even getting 100% WOT. 

 

If you're curious about calculating WHP from my times/speeds, weight should be 2550 +-50  with me in it. I have been keeping a weight budget of EVERYTHING that goes in or out since last year when it was corner weighed.

[metalmonkey47]

Is the muffler chambered or glass-packed? 

As long as MAF housing diameter is stock you should be good. If you were to ever change MAF diameter, you have to tune to re-scale the MAF.

 

You can probably get away with doing the 'ol brake parts cleaner trick to find vacuum leaks, spray it around the surfaces and listen for changes to idle.

[Maschinenbau]

I think it's a chamber muffler, but no markings so I have no idea what's inside. 

 

I'm going to check pedal potentiometer range on and off car to see if my pedal stop is holding it up. If it never goes fully WOT, then it may have never gone into power enrichment / open loop mode and left power on the table. How embarrassing would that be lol.

[Maschinenbau]

Well I might have found something here. Take a look at my pedal stop. I put this in back when I was having the Accelerator Pedal Position (APP) sensor issue. I thought maybe I was over-flexing the pedal when going WOT, causing the sensor to short/open and put the car in limp mode. I also doused the thing in contact cleaner, since the sensor getting dirty/dusty from bodywork and paint was the more likely problem. 

Maybe it's limiting the total sensor range, possibly keeping the ECM out of WOT? Let's find out for sure.

The APP has potentiometers inside, which are basically resistors that change based on movement. The ECM reads this in as pedal position and does stuff to the engine accordingly. 

 

Sensor 1: 

• Idle position: 2.83 kOhm
• "Floored": 0.41 kOhm, 0.35 if you push really hard
• Actual WOT: 0.13 kOhm

Sensor 2:

• Idle position: 0.28 kOhm
• "Floored": 2.71 kOhm. 2.76 if you push really hard
• Actual WOT: 2.91 kOhm

I don't know what exact TPS% this all translates too, but looks like I never went WOT at the drag strip, or at the most recent autocross. D'oh! This is potentially very important because this car, like many other modern EFI cars, goes into an open-loop "power enrichment" mode at WOT. How much power difference can that make? I guess I won't know until the next time I go drag racing, but I adjusted the pedal so I get the full sensor travel and my hopes are definitely back up.

[metalmonkey47]

Yep, that sounds like it had great potential to limit you on power. 

Consider ditching that chambered muffler in the future for a packed muffler or resonator. There's a reason literally every aftermarket exhaust for VQ cars uses packed muffler over chambered, they love to breathe. 

[Maschinenbau]

Mild update. Went to Caffeine and Octane two weekends ago. Datsaniti got a LOT of attention! Dad doesn't quite get it, but was surprised by how many people recognized the engine and appreciated what was done.

 

This whole I've still been unsatisfied with the brake pedal feel. I have also never been able to fully bleed the LR caliper because the bleeder screw broke off forever ago, so I've just been loosening the hose connection. Turns out that caliper has also been sticking. I noticed it last time I went drag racing. Brake smell and a HOT hub means I was dragging a brake each run. I'm guessing the burnout got the caliper hot and it seized while pulling up to the line. Luckily it loosened up on the highway. So I went ahead and replaced both calipers and pads. Also the parking brake was in standard Midwestern shape, rusted to oblivion and missing half the friction surfaces, so I cleaned that up and put new shoes in. Everything feels so much better and more confident.

 

This past weekend I went autocrossing. The car felt amazing and I drove pretty well! 30th out of 146 overall. Nowhere near FTD, but right up there with some very quick cars. Check out this E-Mod Jeep!

 

And I finally got around to de-sketchifying the nitrous fuel tap situation, now with minimal hose connections. This is actually cheaper than the original solution, and now NHRA legal.

 

 

Oh and the accelerator pedal sensor issue popped up again on the highway once. I can't risk this happening during a drag run so I put a different junkyard unit in.

[Maschinenbau]

 Here's some more autocross pictures from Sunday

 

 

 

[Maschinenbau]

Last time I went drag racing, tech inspection didn't like my filing cabinet drawer battery box. It wasn't sealed enough since I only tacked the seams together. This tub of kitty litter and a strap oughta do the trick.

 

 

 

 

I also bevel cut the hater pipe