EF Ian

Nice photos, shes a great looking car. Looks like you took those photos in bright sunlight, its always hard to get good shots in midday sun, best time is late afternoon and sometimes in the morning.

Thats a good weight for that setup, gives me hope.

I am with a specialist insurance company due to the mods. I actually had to renew it the other day (nearly £800 ) so I took the opportunity to check if it would be an issue, for them it was't and wouldn't cost any more since my car is already super heavily modified. I don't see it like that, you are connecting the two suspension towers, connecting the towers to the rocker panels which provide a lot of the strength for the car and also providing a fairy rigid bar connecting the two rockers together and then theres a bar coming off the top of the towers whihc must help somewhat to provide some vertical stiffness for the towers upward against upwards forces. I would consider connecting it to the roof as I can use some plate in the middle and still run the trim as I would just need to trim a section out the plastic to allow it to fit. My front is as reinforced as I can make a road car so I'm no longer worried there. Honestly my front end feels solid and no creaking or any visible flex no matter where I jack it up. Heres the cage I have in mind (just imagine all the lines are where they should be as I couldn't get it perfect in paint) I plan to have the main hoop uprights part recessed into the well. With this design I reckon I can still run my stock belts. The bars in yellow are optional if they are thought to be needed. I do realise that without a diagonal in the main hoop I am loosing strength but I don't want to sacrifice the room and its not like I am racing in any competitions plus I'm sure even without I'm still going to be much safer than with no cage. Correct in both cases. But I think the cage above will be solid and still let me run my stock belts. Of course I am not a cage designer so it could be deeply flawed. I guess modern belts mounted to a small floor reel with the upper mount mounted to the cage would work. Other ideas for fun, tell me what you think. With no cage what is better, x on its own, bar on its own or both like below or is both not adding much other than weight?

My seatbelts mount on the top so I'd rather have them just in front of the top on the vertical. Just looked it up, thanks, got some ideas from that. Totally wouldn't want a full cage with door bars, but with the design I have in mind for my half cage I can't see it getting in the way at all. My frame rails are good and I will be extending them to the rear subframe so its good to hear this proves worthwhile. Thanks. I actually read that thread before I even bought my Z. I have or will have 1, 2, 4, 7, 8, 11, 12, 13 and possibly 3 as we are discussing here. With my design that I have in mind I do not believe I will loose any seat travel, at least not any of the adjustment I would need for driving. I may make a removable harness bar as I would only be using harness on track, drag strip or runway.

Such a great looking Z. Hard luck on the AC, I hope you get it sorted soon without too much more hassle. I'm lucky that I do'n't require AC where I live so I don't have that headache, although sometimes I do wish the weather was warm enough often enough that i did require it.

Not sure on exact brand, but they both came from MSA and I am happy with both of them if you are thinking about them. Thank-you very much fellow RB-Z brother. Hope to get this thread updated this week.

I have full interior, radio with 2 small speakers, 10kg's of sound deadening, lightweight carpet throughout and thats it for the comforts. But I do have 225/50/16's all round and will soon run 245/45/16's on the rear. I have big brakes all round, but the front setup weighs no more than the stock did and the rear didn't add much either over stock. Other than that its only what the RB added over the L26. Plus beetween removing unused parts, lightweight battery, coil-overs being lighter and some light weight body parts I've removed over 50kg from what it was stock. I would now be happy with anything under 1200kg with a small half cage. With 490HP and 490LBFT it still makes for a decent power to weight. I dream of upgrading to a titanium exhaust system at some point down the line.

Interesting thread, These S30's are a lot heavier than I thought an hoped for. I was hoping for 1100'kgs for my RB-Z. Thats with Carbon bonnet, FRP wings, lighter coilovers, alloy hubs and thats about it for the weight saving. Its looking like I'd be lucky to hit 1200 once my half cage goes in (estimating 25-30kg) Bit disappointing. Next car project needs to be lighter. Will weigh mine once current work is complete.

Thanks. I wasn't sure on the wing at first, but now I wouldn't be without it. I have a build thread, its long overdue an update which I'll try and do soon, some major works coming up soon. http://forums.hybridz.org/topic/113907-78-rb26-260z/

Nice work, thats great, I am only aiming for 245's on 16's so that will be easy compared to this. I may be very wrong here but I make them more like +16.5?

Love your work so far, fabulous fab work. Think you are correct regarding the cage, a bar between the rear strut towers will add some more strength, but its barely going to be noticeable over the cross brace you already have so better not to add the extra weight.

Your car looks so similar to mine:

I still know which I'd pick. It is amazing how small they always look compared to just about any other car though.

Thanks for your response and your advice/opinions, its appreciated. Well, thankfully my car is actually quite stiff, but that doesn't mean it shouldn't be improved. Theres no visible drooping no matter where I jack it up and even jacked up my doors still open and close without issue (not like in my Civic) Theres also no creaking to speak of from the interior panels. Shes a solid girl so perhaps I'm doing work for nothing, but I can't help thinking I'll have problems eventually with running 490ftlbs and 245 semi slicks. Actually one of my biggest surprises after buying the car originally was just how stiff she felt, I was expecting an old classic like her to be sloppy, but there wasn't a bit of that even with her stock. Perhaps that how she puts the power to the ground better than most S30's I've seen. I actually have already done this, the chassis rails in the bay are strengthened and seam welded along with several other seams on the front area and I have bars going from the door hinge area to the inner upper frame rails and across the the traction rod mounting area. My front end is solid as I had it back to bare metal pre engine swap and carried all this work out then. Lucky because I can't run a strut brace as the twin turbo pipe on the RB sits too high to fit a strut brace over.

Not cost, but weight and primarily a road and I don't want the hassle of having a cage in the front, plus its not the look I'm going for, trying to keep the style minimal, clean and close to original, a full cage just doesn't fit with the rest of the car. If it was mainly a track car thats a really good idea. Bulkhead isn't really strong enough, you need a full to do that effectively, as then you can link the bars from the strut towers up to the rest of the cage. Unfortunately I can't run strut bars in the front as my engine sits too high.

Thats fantastic, it looks great, a true work of engineering art. Plus the passion and patience to keep the build going for ten years. Make sure to take plenty of videos when you get her out on track.

Nice work, enjoying your videos. Keep it up. Might it be worthwhile extending the frame rails to connect up to the rear sub frame while you are at it? And possibly adding some bars at the front. I will also be adding another bar going from around the same location on the bottom where that bar is over to near the traction rod mounting area.

Thats a valid reason for not doing it, I didn't actually think of that as you tend assume body panels wouldn't flex much, but for sure there is a lot of flexing goes on with S30 at the rear quarter panels as they lead up to the roof. That should be an area for concern, however while there is side protection in the stock doors, its still very poor so you might not be loosing too much protection.

Fair enough. Don't take this as me criticising you, its not, just asking a question. I assume you've jut had the car painted, and therefore you chose the blue? How come you went with blue instead of going for a dark grey to match the carbon fibre, from far back it would look all one colour but up close you would notice the lovely carbon fibre parts. For me the main part that stands out too much is the blue under the doors.

How about getting the rest of the car skinned in carbon fibre so it looks like the whole car is carbon fibre?

Well, I guess the main reason most people fit a cage is for safety however I'm mainly wanting it to increase the strength of the chassis so I was hoping to get some responses as to how much difference those running a cage felt it made to the rigidity of the chassis. Response so far from anywhere I've asked is very positive that they notice a big increase in how stiff their chassis feels. This is what I was hoping for as to add a half cage will mean adding nearly 30kg of weight and given how hard I've tried to save weight in my Z I had to know that this extra weight would be worthwhile. At least with the weight I've saved recently the overall gain won't be massive as I've saved over 10kg with carbon bonnet, over 4kg with fibreglass wings, a couple of kg with alloy hubs so it might only end up 10kg heavier than previously. Considering going to a fibreglass front bumper and getting that chromed, will look original but should save me a fair amount of weight. Just that its expensive as I was Quoted over 700 to chrome it, and that is Pounds sterling, not dollars. Cost I'm not so concerned about as I've allowed up to £1000 for the work, I think this should see it done. I'm going to be going with a design similar to this.

I had no luck finding anything useful with the search.

Its more expensive than it is to chrome a metal one due the process taking more time as before the nickel and chrome go on it needs 3 or 4 coats of conductive copper paint applied with sanding smooth in beetween each coat. Good choice staying chrome, you need it to break up the carbon fibre and to help make the carbon stand out. This bumper here is an FRP one that has been chromed, as you can see, you couldn't tell it wasn't a metal one.

You can still get FRP bumpers if you want, they can be chromed exactly like the metal ones can. Doing this on mine to save weight.

I'll never run more than 225's on the front, don't need more, no power steering and don't want it, more would make the steering heavier, bigger wheels are heavier and don't often feel or handle as well despite more rubber. For me a 16x8 with offset of 5 or 10 is perfect for the front.