Got Tips? 15hrs at Road Atlanta in a Z31

[Trap Star]

Alright fellow Zilvia folks. Looking for people that have experience with Z31's. My friends and I picked up an 86 N/A that we'll be running in a Lemons race at Road Atlanta in December. If you don't know about Lemons, the main thing to know is the budget is tight. $500 is the max spending limit for the car and anything we do to it that isn't safety related. The car will run, has 250k+ miles, and is a 5spd.

Basically we'd like input on two things as of now:

1) What should we expect to break?
2) What would you be sure to do to your Z31 before hitting the track

Open to any and all input, even if its just to call us morons for attempting this (we are).

[NukeKS14]

You're going to have a blast regardless. Ran RA in 15'. One rainy session and a couple of days worth of dry. Not a lot of help with the chassis here but best of luck. I'll see if I can't turn up some info for you. What room do you have left in the budget if you don't mind sharing. Are you pretty much tapped out already? I'm ignorant of class rules but what can you do with wheels/tires?

https://z31performance.com/forum/z31-performance-upgrade-forums/suspension-chassis-and-brakes/71-n-a-z31-for-road-racing

Slotting the strut towers for negative camber seems like a worthwhile mod.

http://xenonzcar.com/z31/issues.html

Found that as well. Hopefully someone with firsthand experience will chime in.

*edit* Ok so we're working with These? (https://24hoursoflemons.com/prices-rules/)

4.1: Total Investment in Vehicle Can Not Exceed $500: Except for items described in Rules 4.2 and 4.3, the total spent to purchase and prepare any car may not exceed $500.

4.1.1: Lame-Ass Rationalizations: Cars that ?should be? worth $500 don?t count; cars that ?were worth $500? before you spent another $2000 to fix them don?t count; cars you?ve owned for 20 years and spent more than $500 on during that time don?t count; ?it would have been worth $500 if it didn?t already have a cage? doesn?t count. Five hundred dollars means five hundred frickin? dollars.
4.1.2: Lame-Ass Rationalizations About Parts: Same deal. ?Free? parts, parts given to you by your buddies, parts left lying around the shop?that crap doesn?t impress us. It?s worth whatever the last real guy paid in the last real purchase. Don?t think you?re clever.

4.2: Safety Equipment DOES NOT Count Toward $500 Total: Safety equipment described in Section 3 DOES NOT count toward the $500 total. ?Safety? refers to things that can save the driver?not things that can save the car.

4.2.1: Beside the items and processes listed in Section 3, the following are considered safety-related and therefore exempt:
Wheels, tires, wheel bearings, balljoints, and brake components
Exhaust systems downstream of the header/exhaust manifold (NOTE: Turbos and related components are NOT exempt from the $500 limit. Nice try.)
Windshields and wipers.
Driver comfort & information (steering wheel, shifter, gauges, pedals, cool suits, vents, heaters, radio)
All fuel hoses, fuel fittings, fuel filters, and related mounts
All fuel-system components upstream of the fuel pump, including tanks/cells, mounts, fillers, vents, etc. (NOTE: Fuel pumps, carburetors, injection pumps, computers, and individual injectors are NOT exempt from the $500 limit.)

4.3: Registration, Insurance, and License DO NOT Count Toward $500 Total: Registration, insurance, or license charges?assuming for some reason you bothered?DO NOT count toward the $500 total.
4.4: BS Factor: To prevent cheating, all cars will be inspected by a panel appointed by the Organizers. At that time, all teams will be given an opportunity to describe the car?s purchase and prep. If the panel believes the limit set out in Rule 4.1 has been exceeded, it will assign a Bullshit Factor (BSF) equal to one BSF per $10 above the limit. The entry will be docked one lap for each BSF assigned. (Ten dollars = one BSF = one lap.) Entrants are very, very, exceedingly strongly encouraged to bring pre-race-prep photographs, verifiable receipts, notarized testimonials, plus any and all other supporting evidence to Tech/BS Inspection. Or at least make up plausible-sounding stories in advance.

:rofl: Nice.

I'd recommend;

- New wheel bearings since 1), they're exempt from your $500 cap and 2) Guessing the car is in unknown condition. Reduction in rolling resistance as well as reducing hub temps around your brakes which are going to be getting warmed over already Rock Auto has them CHEAP (https://www.rockauto.com/en/catalog/nissan,1986,300zx,3.0l+v6,1209563,brake+&+wheel+hub,wheel+bearing,1672)

- Slotting strut towers to gain some negative camber. It's free grip.

- Whatever you can do to take some slop out of the suspension and steering. Balljoints are exempt so sweet. If it were me I'd grab some liquid urethane similar to this (https://www.amazon.com/Polytek-75-60-Liquid-Polyurethane-Rubber/dp/B075TJ2BPN) for $50 and pull the suspension components and make some new bushings. Could maybe get some motor and tranny mounts out of the deal too.

- Cut the dust shields off of the rear brakes. Either grab some cheap ducting and incorporate it into the shields on the front brakes or remove their dust shields too. New pads all around (exempt) and brake flush with ATE Typ 200 or above.

- clean/adjust MAF/AFM (http://xenonzcar.com/z31/AFMCalibration.html)

- Verify timing/advance a few degrees perhaps? what fuel are you running. Engine is robust. should hold up if you're running above 87. if 87... not sure long-term.

- If there's money in the budget, generic cone filter on the intake maybe? something like this if you can swing it for a few bucks.
:rofl:
https://i41.photobucket.com/albums/e295/mrdudex5/MikesZ31/enginebay/Sept012008/SANY0793.jpg

kidding on that last one.


Sweet! found a downloadable FSM for your car too. Could come in handy.
http://xenonzcar.com/z31/FSM/1984fsm.php

[Trap Star]

Oh I'm definitely looking forward to it. So long as none of us catch on fire its gonna be fun hahaha.

So we definitely have some room in the budget. At the moment we have maybe $100 non-bs dollars or so but we were able to salvage a lot of parts to resell and have some "plausible stories". As far as the motor goes, its definitely high miles but it was a 1 owner car and from what we found inside it we think he was an aircraft mechanic. Hopefully that means its been maintained. Almost every bushing on the suspension is shot so we are definitely planning on addressing that. As for fuel we can run whatever is going to work best for us.

Intake we were honestly just going to do a PVC pipe with a filter and some nipples for vacuum lines. Also going to find some cheap E-Fans to run. Definitely going to look into wheel bearings and check out the strut tower slotting, hadn't considered that yet. Also planning to do some things you can't readily see as well, like a new oe type clutch, spark plugs, stuff like that.

On the subject of brakes, we were probably going to just do upgraded rotors and pads. Tires have to be shit basically. I think minimum treadwear is like 190. As for wheels we were just going to pick up some Z32 wheels for it and run those.

[NukeKS14]

Sounds like a good start. You're most likely not going to see jack diddly from the intake, my dry humor gets lost on forums. Removing the cat on the other hand would make it a bit more free-breathing. Guessing since that's exempt you were going to just toss a straight pipe on it.

If you stuck to mid grade or above fuel I think you could advance the distributor enough to see some gains and still be safe.

Since you'll have the tranny off already, had you considered a lightweight flywheel?

Some more info (https://z31performance.com/forum/z31-performance-upgrade-forums/driveline-aa/1465-interesting-flywheel-clutch-pressure-plate-interchangability) on what flywheel and clutch combos are interchangeable between the VG30E(T), KA24DE, and RB20/25DE(T). Be careful here. the VG30DE(TT) looks like it's got a different bolt pattern\count (8 over our 6) and wouldn't work.


You can source the RB20 flywheels for less than $150 on eBay (https://www.ebay.com/itm/XTR-RACING-LIGHT-CLUTCH-FLYWHEEL-fit-NISSAN-SKYLINE-RB20DET-RB25DET-RB26DETT/133403188186?_trkparms=ispr%3D1&hash=item1f0f731bda:g:VFUAAOSwFe5Xzz~B&enc=AQAEAAACcIQvEcHUrT7nmUC3yY5qbPyaBN1nJEDYW8Myyp sJPgXKMrJ5ZnoiL5k7zr%2FQKfBqza4qadgghli8YCIqbBwQqS gGFFF9hJ6wkEpjpHS8FotFIarEJNEKeHTmqhQ%2BHXJR8wR7CO %2FmRWNKhea8ytsg33f7iRz9w2A3neMTkmqFrUNIl7v01KsYyz fwrUP%2FzVWF0gTTQLNTRrrz8fGFm5MgLO1VAcCStX7YYvwq9m FBozESYPG2X99bUrilm71I5B7Sbj9pm0uL0Ri1VaaRxmE37vLJ wKkIH9aVCBdOljbUbFlYe%2B6gUmUzcpnYyKf9ECT3hKe1bvdm zR1oUXQKUiUaqpNYDg%2FzoYgFBUFR1WwaoMa5UKEtc43RkcVF 58HJekhkmCPCejm6%2BdOzc3g3u%2BoSprpFo7UiDghAQwit8p lHCbowalb%2Bm4wgVw6q2cXUQ86eTY%2Fy7cXOKQfxkUaGht2X QqoXMLStF%2B%2BmZV0wYRDlS2p0LleqboHbvCcK2JJzAb%2FD qkiamqSi392BPO0dsQLB9AgK8hwm0FcSQhwpBoBTxQpGEPLKr5 h2YuOxIqies%2F7N%2FGEeGVj5QKjutEAbB1X41lIo6P5aKD8E 0AP5Hkw6aAw3R1V6ywV8RndepanUtkgn0JzyaZn4Pil%2FYaoz Gvn5rpGGmOEE6aUtW2w131VYpb2u%2B8Y9QJQb%2Fj3xR2I0ZN yEqMNqPU4nAoIOPTio4S5grvBqmVcHUaGKkp9W92a9VAaxQ2MO i%2BJ0smH6H6Ok8%2FiWwafmVSPf3QlxJIYJMm%2Fj62avE%2F 1F4EdoVVAtQ94TiVdqYuqUwv%2BXlT2hJpx0zsD05w%3D%3D&checksum=133403188186eaca7dd110934896bac3a035fb6ae 1cf) all day long. They call it a white bunny setup for the KA engines. I'm running one myself. I've never heard of anyone putting it on a VG30E though. Seems plausable. I can grab pictures and take some measurements if you're interested.

Stock ignition system seems pretty stout to 300/400 whp (just an aside.) Might do to toss a new rotor in there and clean off the points on the cap though with some good ol' 80 grit.

As for the electric fan, I have a used OEM electrical fan out of an S14 240sx if you want it. You probably need something that's going to pull more air like out of an old Taurus or something similar though.