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Jesse OBrien

Driven Daily Hillclimb 2016 Build

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I wish I could remember the source - but it was a very credible one, that told me the Z32 suspension is actually one of the best ones out there - as far as geometry, etc.. I'll see if I can fish it up, Found it! 

 The guys name is Jim and he worked for Roush for a number of years on their Trans-Am cars and IMSA cars - here was the post:

http://corner-carvers.com/forums/showpost.php?p=25165&postcount=46

 And I asked him here,(his post was at the end of the thread - he didn't give me any more info as by the time I reached back out, I had decided on the FD suspension).

http://forums.corner-carvers.com/showthread.php?t=4809&highlight=z32+suspension+fd

 

Jim doesn't roll out his credentials very often - but he was working on suspension design well over 30 years ago.  That was the basis for my Z32 thoughts.  In the end, where the upper arm mounted wasn't much of an option for me.  You'll notice the Z33 is not a whole lot different beyond some aluminum parts.  

Sounds like you've got it worked out - I hope it works out great and you can finish before the season!

Edited by Bob_H

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This weekend was a lot of math. I already knew that the g35/350z front subframe would be wider than the stock 280z subframe. I also know that the 240sx rear subframe is wider than the stock 280z rear subframe.

 

The stock front and rear subframes are designed to be the same width.

21846530656_669404b6bc_b.jpg

 

After math-ing, I came up with the following:

* Original hub-to-hub distance: 53"

* g35 hub-to-hub distance: 60.8"

 

That's 3.4" wider on each side

But wait! There's more!

 

The original Datsun wheels were 14x5 (15" diameter by 5" wide), and I'm bumping up to 17x8" (8" wide) for street wheels. I need to accommodate 17x10" race wheels, and my math suggests that I'll have around 6" of those wheels outside of the hub (per side). That's 5" more 'wheel' outside of the hub than stock.

 

At the end, this all means I'm going from a fender width requirement of 55" to 72", which is 17" wider, or 8.5" wider than stock, per side. This car-shaped thing is starting to show how ridiculous it really is.

 

My fender plugs just keep growing and growing. It's starting to get ridiculous.

25499927923_2b27c3af7c_b.jpg

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I suppose it's time to start talking about what's going under the hood. The current engine is a test mule, something I picked up off Craigslist that may or may not run. A friend of my fabricator happened to have a 13b that had been sitting on a shelf for a little while. I made an offer on it, and just **barely** squeezed it into my budget ... but this solves my "will it run reliably?" problem pretty completely. It's a ported 2rotor running on VEMS that's already been tuned, and is ready for whatever I want to throw at it ... as long as I'm throwing lots of fuel and oil at it.

 

26131549206_8467ce2434_b.jpg

25554844963_f9077660bd_b.jpg

 

According to the dyno results on this engine, it should be good for better than 350whp. Sometimes, you get lucky and the right deal comes along at the right time. This was my time.

 

It's going to take some time to get it in the car, get the harness wired in, and build the body harness for it, but I'm in full-on thrash mode now. 14 weekend-days left before the first event.

Edited by Jesse OBrien

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...After math-ing, I came up with the following:

* Original hub-to-hub distance: 53"

* g35 hub-to-hub distance: 60.8"

 

That's 3.4" wider on each side

...

 

The original Datsun wheels were 14x5 (15" diameter by 5" wide), and I'm bumping up to 17x8" (8" wide) for street wheels. I need to accommodate 17x10" race wheels, and my math suggests that I'll have around 6" of those wheels outside of the hub (per side). That's 5" more 'wheel' outside of the hub than stock.

 

At the end, this all means I'm going from a fender width requirement of 55" to 72", which is 17" wider, or 8.5" wider than stock, per side. This car-shaped thing is starting to show how ridiculous it really is.

 

My fender plugs just keep growing and growing. It's starting to get ridiculous.

 

 

 

I think you don't need to go as wide as you are thinking.   I would throw out the stock/OEM rim side of the equation because it assumes the stock rim was the largest you could fit under a stock fender which is not the case.  You can fit a 7-8" wide rim under a stock fender on stock hubs.  As such, I would stick with a 4" width increase.  I have a 10 and 11" wide rims up front on my "Super Datsun" and it still has some room on the IMSA flares, (granted, not much).  With just ZG flares, people are approaching 9-9.5" wide rims and the "wide ZG" flares accommodate out to 10 or slightly more with perfect offset.     

 Here are some threads with those discussions:

 

http://forums.hybridz.org/topic/41406-4-sets-of-rs-watanabe-in-stock/?hl=%2Bwidest+%2Bunder+%2Bstock+%2Bfenders&do=findComment&comment=340575

 

http://forums.hybridz.org/topic/112168-what-size-aftermarket-rimstires-for-240z/page-2?hl=+widest%20+under%20+stock%20+fenders

 

In short - the flare size you have in that pic would likely accommodate a 12" wide rim! 

 

Here was me asking similar questions way back when...  This was me gathering the info on my FD suspension swap:

 

http://forums.hybridz.org/topic/5922-what-is-your-track-width-front-and-rear-scottie-pete/?hl=%2Bwidest+%2Bunder+%2Bstock+%2Bfenders

 

In it shows some good info for your purpose.  In particular, look at what Pete Paraska fit under stock fenders and with what offsets - that shows about the max under a stock fender,(I think rolled), with coil-overs. 

Edited by Bob_H

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Because the new engine is going in, I now have the 'leftovers' of stuff that isn't going into the car in my shop. That means cleaning, organizing, and storing needs to happen (before the car shows up). This is unacceptable:

26167986422_c4ea50c059_b.jpg

 

 

I started by shuffling some parts around, and making room in the 'engine room'. Because I know I won't using OEM EFI on this car, I decided to tear all the extras off of the assembled-spare 13b.

 

I started with this and a beer:

26218978145_b3945d14ef_b.jpg

 

And ended with less clutter, and no beer. Here's the mockup housing assembly next to the 'assembled spare' block.

26289512761_f1749582ac_b.jpg

 

The turbo goes on the 'spare turbos' shelf. If there's any kind of market for it, I'll happily sell the harness/ecu/manifold/turbo/lines off to whoever is interested enough to make it worth putting them in a box. I have no idea what it takes to convert n/a to turbo, or if any of this is worth anything.

26289506351_6b68ce1093_b.jpg

 

One interesting discovery I came up with is that these two engines apparently have different rotor housings. Otherwise, they appear to be identical.

 

One with no markings on top

25752998303_b9fc9a169f_b.jpg

 

The other with licensing markings on top.

26289515661_ddee18d06e_b.jpg

 

As for accessories, here's one of the spare transmissions (I now have three turbo2 transmissions), and two of the intake manifolds (again, I have a total of three right now).

26082877710_8e6e5108cd_b.jpg

 

That emissions block-off kit is really disappointing. It's so thin that I can't use the stock studs. I can either draw up a DXF (just put these on a flat-bed scanner and scan them 1:1) and have Big Blue Saw cut out some proper plates, or pull those studs and use bolts instead. Generally speaking, I find that steel studs in aluminum don't come out as easily as I'd like. I'm leaning toward slightly girthier blockoff plates.

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Most of tonight was spent simply cleaning/organizing. I still don't have a clean floor, but I did get to dig the dashboard out of the basement and start prepping it for molding.

 

For those who don't know, s30 dashboards were made of vinyl-wrapped foam that was susceptible to cracking if exposed to sunlight for more than a few years. It's pretty close to impossible to find an original, un-cracked dash these days, and most people just toss a plastic cap on top and call it good. Generally speaking, that works great. It looks good, and the dashboard doesn't need to be structurally sound.

 

However, the stock dash is pretty heavy. I really can't justify trying to use those old original gauges either, especially with a standalone ECU where I can drive any gauges I want. I do love the design of the s30 dash though, so I decided to repair the surface and pull a mold from it. Fiberglass should work just fine for this.

 

The first step is to fill the large voids left by the cracks. I used some 2lb expanding urethane foam, because it's so easy to work, is fairly rigid, and is stronger than body filler when filling large gaps. I think it took around 15 minutes to go from a badly cracked dash to a mostly-smooth one.

 


 

A quick rasping, and I had this

26128713400_c8d39a1572_b.jpg

 

After that, I mixed up some fiberglass reinforced body filler and because it's chilly out, decided to call it a night. I'll get to sanding it down and finishing the surface after work tomorrow.

26375657966_6a231fc2c2_b.jpg

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I just found out that the g35 front suspension has a twisted crossmember. That means my suspension pickup points are skewed, and I need to get measurements off another car. It's a big favor to ask, but I need someone in New England who's willing to come up to the shop so I can pull the arms off your suspension and measure the pickup points, then put it all back together.

25824568913_ed22b65698_b.jpg

If you want to replace your front control arm bushings, this could be just the right time to go for it. Shoot me a PM here, email me at jesse[email protected], or call/text me at 413-931-1486.

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This is an awesome project. Can't wait to see more progress on this build over the next few months.

 
This next bit is going to hurt then, I'm afraid.
 
I'm pretty disappointed to admit that there's no way I'll be able to race the Datsun-shaped-car for the beginning of this season. I won't even have it back from the chassis fabricator's until after the first event. The only reason for going for quick, expensive solutions to problems (BBS wheels, shiny new engine, etc) was to get the car on the hill for Ascutney 1, and now that all feels like a waste. What's more: The car won't be at the events my few sponsors were expecting, so now I need to refund them for their support.
 
I'm absolutely gutted.
 
However, I can't just lie down and feel sorry for myself. I still have hillclimbs to race. I had to make a decision as to what to drive, and just accepted a deposit on the rx7 (this is the third deposit I've taken on it ... I'm almost making a profit just on deposits now).
 
That leaves me with two options: Rent a car from someone else, or do a quick prep on my CRX. If I had more time to put into it, I'd toss a rwd subframe in it and one of the spare turboII powertrains ... but I have less than a month until Ascutney 1.
 
My best-case scenario is to:
 
1. Swap out the 325k-mile d15b2 (which was a sad design from day 1) for the high-compression d16z6 engine (sohc 1.6) sitting on a shelf.
2. Toss the 225-series RA1's left over from the Miata on it
3. Tune the suspension as best I can in a short time-period
4. TRY to have a cage installed in it (I have one option for this, and he's pretty busy)
 
Budget is going to be an issue. Time is an issue that's even more difficult to solve, so I'll probably have to rent a car for the first event, then drive the CRX for a few events. If everything goes great (which is unlikely, when we're talking about race car prep) I might get to drive the Datsun for the second half of the season.
 
It's going to be a struggle, but I have great friends that I can call in for reinforcements when necessary.
 
25743461596_f6507e6033_b.jpg

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Well, here are some photos of the CRX, then. I can't really do anything with the Datsun until I get it back, and haven't even seen it in months. I started by making a small antenna hole plug, so water doesn't get in.

 

26234347744_2a1726daa2_b.jpg

 

Cut&fit for the fuel cell

26297223773_18f8b57794_b.jpg

 

Pulled the old exhaust, laid out the new exhaust

26294716104_bd56d5eaa9_b.jpg

 

And found a couple cracks in the steering rack subframe. These won't be difficult to repair when I have it out.

26294498104_6ffdfe90c5_b.jpg

 

The engine is ready to come out, I'm just waiting for a second set of hands to do it.

 

26729243882_c87138858a_b.jpg

Edited by Jesse OBrien

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It's not the headroom that's the problem. It's the X in the main hoop. Even if you put a bent shoulder bar in like I did, the bottom part of that X will preclude the base of the seat from sliding back far enough.

You definitely nailed it. It looks like I'm buying a tubing bender, and starting this chassis prep over. It's really disappointing to miss the 2016 race season, but that's how it goes sometimes. I don't expect to do anything but let it rust in the driveway for the next month, then I'll bring it down to the Makerspace.

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Moving the main hoop renders everything else that was done worthless, as I can't make tube longer to fit. It all needs to be re-done.

 

This puts me in a tough spot. I'm getting the car back far later than expected (it was at the shop for 7 months now), and it's in a worse state than it left. On top of that, all the money from selling my trusty old Miata went into getting this ready for the 2016 season. Realistically, I don't have any hope of getting this ready to drive this season, and I may miss Climb to the Clouds 2017 because of it.

 

Still, it's better to light a candle than complain about the dark. I have a year-long membership at the Manchester Makerspace and I may be able to rent a 'large project plot' there for 3-4 months. I'll definitely have to pay for it, but that beats the hell out of trying to make my tiny shop work.

 

I'll need to buy a tubing bender (likely the JD2 model 3) and some dies (likely a 1.75" and 1.25"), and a respectable amount of DOM tubing.*

 

All told, being able to do the chassis work myself is going to cost around $3,000 plus my time. I won't have that set aside 'till August (at best) so it looks like it's just going to sit in the driveway for a bit, while I jig the subframes and finish the CRX.

Edited by Jesse OBrien

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I've been sketching out plans a bit lately, trying to strike a balance between strength/safety and weight. Right now, I'm planning to make the primary safety features are going to be 1.75" x .095" DOM, and rigidity reinforcements will be 1.25" x .060".

 

28827465496_a80c1ceae4_b.jpg

 

I'm drawing a lot of inspiration from Nigel's ETS Ute. I've been through that build a lot, and can only come up with minor complaints (square tube floor, I don't love the trans tunnel design, and I don't like the door bars).

IMG_7520-900x599.jpg

 

Overall, this design estimates out to around 160ft of tubing, and 32 bends. With the combination of tubing, it'll be around 200lb for the chassis structure, including the suspension pickups.

I'm waiting for approval to rent a project plot for 12 weeks at Manchester Makerspace. That gets me a dedicated workarea, and hopefully extra sets of hands to help out from time to time. It's an added expense, but I'd say it's well worth it. My home shop is small enough that I can either fabricate things, or assemble them. This project demands that I do both.

Really, this is what I'm working with right now. I just need to connect it all so that a Datsun body mostly fits on top of it, and a tiny rotary engine fits in front of the firewall.

27939372222_bb26f41533_b.jpg

 

Also, I've been considering a change in tire selection. Maybe overkill ... but maybe "just enough kill".

 

27803913583_47c320e029_b.jpg

 

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