240z SCCA vintage race car, restoration

[rossman]

3 hours ago, AydinZ71 said:

feels like folks aren’t using the forum very much

I still check out quite a few HZ posts and read most of yours here and on Instagram.  A lot of folks moved to Facebook years ago.  I'm old skool, preferring forums over the other social media options.

[AydinZ71]

2 hours ago, rossman said:

I still check out quite a few HZ posts and read most of yours here and on Instagram.  A lot of folks moved to Facebook years ago.  I'm old skool, preferring forums over the other social media options.

me tooo!!! I looked at FB, but I just can’t… it’s too much. Even IG is too much at times. This forum has a rather self-selecting nature to it. Trolls tend to get bored, and frankly the “old school” folks know a heck of a lot more and are experienced. Not interested in a Johnson measuring contest, if you know what I mean 😕 

 

not that FB and IG are all trolls. It just seems like the platform is vying for my attention more than I am comfortable with. 

 

The idea that folks get good (or bad) ideas from me posting is enough motivation. I enjoy having my thoughts challenged by experienced people. Conversely, I would rather not over-share.

 

Thanks for following, Rossman! 

[AydinZ71]

Cut off the little unibody appendage forward of the fender. Mocking the “nose cone” mounts, and contemplating the hood mounts.

 

one fender officially fits and gaps look good (so far). 

 

going to box the nose cone with AL sheet. 

[tube80z]

On 11/25/2021 at 9:45 AM, AydinZ71 said:

Thank you Cary! I must have been channeling your thoughts or something because I finally gave-in and added the critical “inward” facing brace. This late in the game, I am hyper critical about adding weight, but I weighed the 18-gauge 1” tube I am using, and all-in it will only be 3lbs added (including the cabin attachment to and from the firewall/roll-bar.

 You're welcome.  I'm learning lots from your build too.  Every time I build anything I always find a better way to build it and  make it lighter next time.

 

On 11/25/2021 at 9:45 AM, AydinZ71 said:

 

thanks again for or you input Cary! Sometimes feels like folks aren’t using the forum very much, so your comments motivate me to continue posting. 

 

I love watching the progress.  I still come to see what people are doing and what the latest things people have found on newer cars and to keep the Zs going better than ever.  My latest find is the Bosch i-brake system.  Electronic brake booster rather than needing any vacuum.  More later on that.

 

Keep up the good work,

cary

 

[AydinZ71]

1 hour ago, tube80z said:

I'm learning lots from your build too

I’ll take that as a compliment! I probably try 5 things before the 6th one qualifies for a “good idea” 😂

 

1 hour ago, tube80z said:

come to see what people are doing and what the latest things people have found

me too! I learned about the megajolt (EDIS) crank-fire ignition on here. Greg hadn’t heard or it, but who would when you can afford electromotive 😂 I find it difficult to separate the “marketing” from truly value-add components. In many cases, something hand-fabricated is the only way to add adjustable and still meet class rules. 

[AydinZ71]

Rear hood latch complete. Sounds rediculous, but this was HARD. Needed to get under the car with the hood on, center the hood and weld it in place from underneath. Of course I could have oversized the latch hole considerably and just adjusted to fit, but I didn’t want to weaken it. Now into the front mounts, which are a heavier gauge quick-latch (3/8”).

 

OH, and I got my adjustable cam gear. 

[AydinZ71]

front hood attachment points for 12lb fiberglass unit. 
 

Anyone who has mounted a custom hood with new attachment points for the first time knows how hard this is… like, yell loudly from time-to-time, frustrating. Like… 2hr estimate turning into a week, difficult. 
 

Using very thin-wall stainless tube. 4’ of tube is under a pound. Pin is 3/8” quik-latch. Pin mounting surface is 16-gauge CS. 

[jhm]

Nice work, Aydin...impressive as always.

 

This is one of the reasons that I’ve shied away from composite body panels.

[clarkspeed]

That looks damn sturdy. Nice work. Some use 1/4 or 3/8 round steel for supports just so you can adjust a little with a big lever/hammer. Yours looks beautiful and light weight also, AND very exact.

[AydinZ71]

@jhm @clarkspeed thank you both, sincerely. I may be a smidge perfectionist, and I say that equally as a criticism and an asset. I think I have frustrated the heck out of Greg by now LOL. “Dude get that tub on the track” haha

 

I have some serious EP GCR challenges with the tube steel, but if I suck as a driver I doubt the judges/competitors will press the point. I suppose it would be a welcome problem to have. Most of this will be hidden under aluminum cladding. 
 

No better feeling than when you take the hood back off, place it back in the car, and hear that sweet “click” noise without the car putting up a fight.

 

you can see what I did with one of pics. Welded the tube into the general “location”, then welded the pin mounting plate directly to the tube with the hood on, all from underneath. That’s how I ensured there was no lateral load on the pin. The hood flexes quite a bit, so I could not rely on dimensions off-car.

 

i plan to put in two rubber bump-stops mid-way back under the hood, as the hood “sits” flatter than the fenders. Need a little encouragement to sit-up. 

[tube80z]

On 12/9/2021 at 12:10 PM, AydinZ71 said:

front hood attachment points for 12lb fiberglass unit. 
 

Anyone who has mounted a custom hood with new attachment points for the first time knows how hard this is… like, yell loudly from time-to-time, frustrating. Like… 2hr estimate turning into a week, difficult. 
 

Using very thin-wall stainless tube. 4’ of tube is under a pound. Pin is 3/8” quik-latch. Pin mounting surface is 16-gauge CS. 

 

 

 

The one thing I would add is a pin in the middle.  Unless you are doing a lot of work to close up the front end and exhaust the pressure.  I have may pictures taken over the years with various Zs that have the center of the hood bulged up looking like a guppy.  

 

Love watching the progress,

Cary

[AydinZ71]

1 minute ago, tube80z said:

 

The one thing I would add is a pin in the middle.  Unless you are doing a lot of work to close up the front end and exhaust the pressure.  I have may pictures taken over the years with various Zs that have the center of the hood bulged up looking like a guppy.  

 

Love watching the progress,

Cary

gosh darn… ok that’s two folks now 😂

Greg told me the same thing… he recommended a third, middle pin. I was postponing it, but it clearly seems like an important step. Damn, more tube work LOL.

 

thanks Cary! Il get working on that. You can see from the pic below that the ram air will be forced through my engine intake (right side funnel), the fresh air intakes, most will go through the rad, and the rest will be struggling to go over the rad support or under the lower cross support. I plan to add aluminum cladding on the bottom (restrict airflow from diving under the rad support) and and top (restricting air from going between the upper rad support and hood). 
 

as you said, if FG hood bulges in the middle, that aluminum cladding won’t go with it and the air will get by anyways. Once that happens, the hood will bulge even more so no Bueno. One thought would be to pin the cladding to the hood, but I can’t see how that will seal reasonably well, and simultaneously not make removing the hood a PITA. 
 

 

[AydinZ71]

PS: the one-piece fender nose cones will also be boxed out with AL cladding. So will the headlight orifice. Anything to reduce/eliminate the massive turbulent Eddie currents experienced at speed. 

[AydinZ71]

Added a support for the leading edge of the air dam, and a single fastener to keep the dam to resist torsion. Used the thin wall SS tube again so kept it pretty light 

[rossman]

Looks good! I need to do something similar to mine. I have a Xenon dam made from ABS, it is actually bent downwards from, what Im guessing is airflow pushing on it, probably warping from heat too. When I got the car, it didn't have any support so the dam would fold under a highway speeds. To prevent that, I closed out the bottom with a large sheet of aluminum that screws to the lip and made brackets to attach the back to the sway bar mounting locations.

Edited January 7, 2022 by rossman

[AydinZ71]

10 hours ago, rossman said:

Looks good! I need to do something similar to mine. I have a Xenon dam made from ABS, it is actually bent downwards from, what Im guessing is airflow pushing on it, probably warping from heat too. When I got the car, it didn't have any support so the dam would fold under a highway speeds. To prevent that, I closed out the bottom with a large sheet of aluminum that screws to the lip and made brackets to attach the back to the sway bar mounting locations.

yep yep. That’s exactly what this is for  fiberglass probably does a bit better on rigidity than ABS or Urethane (my street Z has a urethane one). 
 

I am allowed to fit a splitter from the leading-edge back to the front-most opening of the wheel well (so basically the whole width of the air-dam).That will keep the air-dam “nose” from “flattening”, but I needed this piece to apply pressure to the nose so all the force doesn’t land on the fenders/nose-cones. Also keeps the leading edge from “plowing” downward as you described. 

[rossman]

It's probably polyurethane since it's so flexible, it's been a while so I don't really remember.  I put an MSA type 1 fiberglass dam on my first daily driver '76 s30.  It had no bracing and as far as I know it never had a problem with it folding under the car.

[AydinZ71]

Yeah I don't think the fiberglass one moves all that much, you are right about that. Still, I much experience driving 100+ mph in an S30. I calculate a completely flat surface would have 36lbs/square foot of force on it at 120mph. Kind of an extreme example, but if I push that hard on the fiberglass unit, it does definitely "plunge" without something fastening the leading edge. 

 

[JMortensen]

I agree with you guys and think it's the pushing back that makes the urethane ones sag in the middle, not any pushing down. Likewise I had a fiberglass airdam with a rubber piece about 3" tall on it, called a Flex-dam. Made in CA in the 70s and 80s. Anyway a friend of mine snapped a pic on the front straight at Buttonwillow, which is not that fast, and the rubber was flapping up and letting a good amount of air under the car. Replaced with plastic lawn edging to fix. Whatever you do, test to make sure it works after you've done it.
 

 

Edited January 10, 2022 by JMortensen

[AydinZ71]

Indeed! Thanks for the comment! I am curious to see how Much of this fiberglass is going to rattle at speed. 
 

started in the tow-eye today. Decided to go with just one, and might as well use the air-dam mount to save weight. Need to reinforce it a bit with a gusset or two and I’m done. Hope it fits under the fiberglass bumper in the future.