Ok ok you may have all seen my last post about trying to make my car handle better than your 4wd turbos in my new quest for getting the most out of my cars dynamics and handeling...the concensus is that its just not possible, it may not be but I am sure as hell not going down without a fight. I jumped into a MX5 yesterday such a tight car, chassis feel fantastic I have been in one before but this was a newer one and got me thinking about improving the rigidity of mine. I have looked at some old posts and some Chewy fellow tried to prove that foam filling chassis rails down not work with a experiment, whilst it was not a bad experiment it had alot of flaws. I have done some pretty thorough research on this last night and it looks like it may be a step forward for me and not to expensive either. Alot of the Jap race cars do it, some of the newer cars from factory have it and also some of the drift boys have done it all very happy with results..... Here is some info one is where they did it to a 300zx as well with good results http://www.modified.com/projectcars/0006scc_project_nissan_300zx_part_5/index.html What I am finding is cars with very good rigidity out of the box that try it dont get a huge difference and why would they, however wet noodles like ours seem to benefit a huge amount from this. Has anyone done this yet?? Maybe a group buy on the foam if anyone is interested? Thoughts on this subject anyone?
My TT is a targa and I can hear the targas creaking when you take one of those killer speed bumps at an angle. My old NA slicktop was tight as, I even have a pic of it with tein flex springs lifting a tyre as it was going down my old driveway If you were chasing rigidity, then filling in your targas with formed steel section, and welding on a slicktop roof skin would be your best bet. Hot rodders / custom speed shops do this sort of stuff all the time, as would some panelbeaters (those who have less of an insurance workload, that is).
A slicktop with A full cage is about as stiff as a Z will be . Adding Foam filling is another thing you can do but cant see it doing too much more. With a targa and foam filling ? the weak point is always up top with pillars twisting /flexing ..only a cage will fix that.
It can still be streetable with the targa top holes filled in, maybe see if some carbon filler panels can be bonded in.
a MX5 is a completely different car. it's light and compact of course it's going to be tighter than your 2+2 which is huge and heavy by comparison. if you want a stiff setup get a slicktop. driving a 2+0 targa is already a improvement and feels tighter than a 2+2. the only way you're going to significantly improve a 2+2 is to cage it. also the zed's chassis and suspension technology is old hat. R32 GTRs don't even handle that well by modern standards. for a street car i can't see the point of all this. if you want the best driving experience just buy something lighter.
Anyone tried rail cross braces? more weight gain than foam but its down low anyway so probably not too bad. I know they're a must have for old charades that put down over 120kW or the chassis fractures
Wet noodles? You serious M8??????................... A zed???? Wet Noodles????? Caaaarrrrmon.....! Even a Z with clapped out dampers and sacked out springs will out rigid (and grip) most comprable weight/size cars For a start, comparing to an MX5 is like comparing apples to oranges as MikeZ32 correctly points out. The 4 seat targa tt zed is a heavy 6 cylinjder car V's a lightweight 4 cyl zip wagon. You might as well compare a go-kart to a Volkwagen. The kinds of funky chassis mods listed above are really only useful at all when chasing possibly only incremental advantages as the very, VERY pointy end of the race car field, ON a race track and advantages that you and I are unlikely to EVER realise in ANY way shape or form. You clearly state you are looking for a NON race street setup. Where in gods name would you EVER explore the chassis stiffness limits of a Kia Rio, let alone a Zed on ANY stretch of public roads where the stiffness is insufficient???? I suggest you might investigate your existing suspension and tyres more closely rather than looking towards the heavens for a rigidity fix....... In fact, I can guarantee you that simple addition of some uprated shocks, springs, swaybars and low profile rubber will satisfy you beyond your wildest expectations in terms of percieved rigidity ON THE ROAD! Perhaps pay a little less attention to car racing forums and their never ending creative pursuit of some kind of edge over the competition and look back towards the real world of intersections, roundabouts, kerbs/guttering and eroded pavement edges rather than worrying about something that an F1 engineer might concern himself with.... sheesh! From a long time bike/superkart/car builder/racers perspective, if even a mildly tricked up (suspension) Zed cant satisfy the desire for a nimble and predictable sports car then perhaps a little less grip and stroke on the manhood may be in order.......! L8r E
the foam would have to do something the convertible comes factory with a foam filled double floor , it also has a big bar welded at the front between the chassis rails and a bolt on brace under the back across the transmission tunnel which i left off once and realised it made a big difference , i also added another brace across between the 2 rails under the gearbox and i made up some under fender braces which am certain make a difference as i have seen zeds cracked in the area they brace . i might try filling my sills with foam when i finally finish the car or maybe just a small cage of some sort
can we get pics of this under gearbox brace, as a vert owner im keen for any improvements to chassis strength. fender barces ive seen come up for sale now and them, i always though they where a bit wanky? reckon they work, and how?
'Verts are a different scenario altogether as they have to be heavily modified in the first place due to no turret fitted. So you have basically a front and rear end attached by a length of floorpan with no rigidity whatsoever! Every vert ever made is more or less a compromise usually has much strengthened sills and whatever to combat chassis flexing and associated handling horrors such as scuttle shake! Caging the vert would solve most of its dramas but look pretty average! L8r E
in my experience so far (stock vert, no mods at all, just 18' rims and tyres) the handling on the vert is pretty good, does scuttle shake a little when cornering hard on bumpier corners, but overall, pretty good...... has good turn in, maybe thats just because its based on the 2 seater though, and its very grippy overall, but when the tail comes out during oversteer, the snap back too straight is pretty ruthless and doesnt feel nice at all, feels very "loose" overall impressions as oposed to my 4 seater, is i think the vert is still very tight, but not as tight as the slicktop or targa top versions, not miles behind the 4 seaters though....
Erm, I've driven a lot of cars and I'd say the 'wet noodle' assessment isn't that far from the mark. A current-shape Mitsubishi Lancer has a more rigid chassis than the Z32, for example. I'd disagree that the MX-5 is more rigid than a targa top Z32, though. Even the NC MX-5 has some very noticeable scuttle shake. It only feels tighter because it's lighter and has a more neutral chassis balance than the Zed.
no pics at the moment and my cars still in 1000 pieces but just as the chassis rails kick up at the front near your feet to go up for the engine crossmemeber i welded some nuts on each side with a bar across between them , also needed some grinding of the bellhousing for clearance as i really didnt want to loose ground clearance , it would have been nice to get some more bracing under there but there wasnt much i could do with out losing ground clearance . im certain the fender braces work , i just did a simple one with bit of box steel .
The doors also take some of the load with those locating pins they have in them and im pretty sure they have a reo in the door from factory which i dont think they normal zeds have . The rigidity probably isnt much if any worse than a targa , that top bit on the targa is pretty flimsy.
your zed mus tbe rooted, my 300zx is one of the best handling cars ive driven, and others have said the same. And i have driven alot of cars, believe me.
