whats gonna break at 300km/hr

[C.A.R.]

I see 300kph a held and maintained speed for a long distance not a blatt on a short straight once

 

[MyEnquiringMind]

I was a bit bored tonight, (OK really bored...) so I did some ROUGH calculations which suggest that it will take 287kW at the wheels to overcome the drag in air at 300km/h... i.e. to reach terminal velocity... will post working if you are interested...

 

Cheers, J

[pauly_adams]

to be honest too scared, also its a little floaty at that speed going faster with out a new front spoiler and lower and better suspension would be just madness, it was happy to keep going and had plenty of pull left in her.

[imackz]

Lol i think that has more to do with driver than hp...

 

3 words that come to mind.... High speed stability look at what happens at Le Mans when the car looses it, it becomes airborne, aero has to be number one.

[620Z]

If you want to hit those speeds then you will need to wack a G-Nose on really. Firm suspension, good quality tyres and a rear spoiler that will keep the rear down but not act as a parrachute. As for breakage if you put in a powerful engine then your drive line needs to be beefed up to the point you simply know nothing will break.

[NZeder]

If you want to hit those speeds then you will need to wack a G-Nose on really.

But that is for a S30 - right at the start he stated 280zx which is 40% better in aero than our brick based S30. The S30 is not flash out of the box but a S130 is much much better.

 

This thread has gone a bit off to the left field...Here is the original post again. I have highlighted the what I see is the real questions in this first post.

 

So I've decided to pull out the rb25 neo out of the 280zx and go for a rb34 setup.. I know this gonna be big power and I'm aiming to hit 300km/hr (not gonna say where I'm gonna try this ) the series 1 rear drivetrain doesn't look too strong to hold that much speed and loooking to do a r32 gtr rear cradle conversion if need be. Is there a shop that can make new drive shafts that strong enough for this kind of abuse? Ive search high and low but there's just not much info or enough people doing this. If anyone has done a rear cradle conversion in aus, for 280, what would be the best place to go?

 

Also this thread is posted in the "Brakes/Drivetrain Components" section so the real questions are related to a rear end conversion to provide a better solution than the stock Series I 280zx setup - assume brakes, strength and handling.

 

So does anyone know of info on these conversions in the S130 chassis or shops that might help this man out?

[luvemfast]

What rear end is Iain using?

He'd have the highest powered 280ZX here.

As someone else pointed out, an R200 can handle quite a bit of powah!

[pauly_adams]

well a r180lsd holds up to the torque from my engine, what you will need is a stronger gbox, much better clutch, better engine mounts, trans mounts etc I have broken all these at least once, clutch and gbox I have shattered twice. better areo will help with downforce and new suspension. all in all everything new or upgraded is needed

[NZeder]

The diff is not the only thing in the rear end. We know the R200 are strong and the ones with the later/large input spline aka GTR R200 can take a lot of torque and powah. R180 are strong too most give them a miss as finding CLSD can be hard.

 

A 240z that used to race here in NZ (divorce = sold and split up by the new owner) with an Alloy 383 V8 (Donovan??) kept breaking R200's and 300zx CV setups as has the TargaZ (LS1 supercharged power 240z) each breaking stub axles, CV axles and plug-in into the diff, but never the diff it self. I think the TargaZ is sorted now with custom stub axles, axles/cv and custom diff input plug-ins. The other 240z installed a Speedway Engineering IRS diff and the largest U-J I have ever seen on IRS - no CV's.

 

So I guess that is what he is looking for - what is the setup that is needed to not break.

 

A few things he has not made clear is as follows.

 

1. IRS is a must?

2. Does the car need to corner?

3. Does he need squat control?

4. Will the car be road legal - ie engineering for ADR etc

 

There have a few drag 240z and 280zx here in NZ with big big HP/torque and they all have solid/live rear ends aka Ford 9" units.

 

All of the above are given I would have thought, gearbox (we know the 71B can be weak, and the 71C too once the torque goes past X, X is well published on the interweb), and engine mounts - make that drivetrain mounts - even without big HP and Torque these fail.

[d3c0y]

Finding CLSD R180s isn't that hard you just have to know what cars to get them from.

I'm just putting one in my car and i agree that 80% of people here wouldn't be able to brake one in good condition.

[Zedman240®]

I don't think strength is so important; he's not going to accelerate like in a drag race... rev to 5K then dump a clutch. It will be a steady go (depending on how long the runway is) so I t think balancing would be a greater issue. Make sure everything is well balanced like from flywheel, clutch, prop shaft and wheels! Then clean up the aero then take out life insurance.

[imackz]

What rear end is Iain using?

He'd have the highest powered 280ZX here.

As someone else pointed out, an R200 can handle quite a bit of powah!

 

Mine is a Kazz competition LSD in the original housing rated to 1000hp.

My chassis has also been completely redone with heavier guage steel, and full length of car, with additional bracing.

[pauly_adams]

I have not once dropped my clutch and yet I have shattered 2 gearbox's, and blown 2 clutches to pieces, I now have truck gears in my gbox and a stage 4 brass button clutch rated to 600kw and 600 ft/lb

[benny]

I have not once dropped my clutch and yet I have shattered 2 gearbox's, and blown 2 clutches to pieces, I now have truck gears in my gbox and a stage 4 brass button clutch rated to 600kw and 600 ft/lb

 

 

wow that seems like an awfull lot of carnage.... is everything balanced properly?

[luvemfast]

wow that seems like an awfull lot of carnage.... is everything balanced properly?

I think its the driver that's unbalanced 

[d3c0y]

I killed my stock gearbox in 4 drives with similar levels of power and talk to Pauly, so not at all. He is making triple the output of the stock engine, stuffs gonna break.

[pauly_adams]

yeh everything was balanced, no vibrations or anything, the worst clutch I used was in fact a exedy HD button clutch it shattered and stripped the material off the clutch plate. as for the driver being we all know I am a bit unbalanced simon

 

[benny]

I think its the driver that's unbalanced 

 

 

love it....

 

 

yeh everything was balanced, no vibrations or anything, the worst clutch I used was in fact a exedy HD button clutch it shattered and stripped the material off the clutch plate. as for the driver being we all know I am a bit unbalanced simon

 

 

 

i see... we all also forget that these parts are up to 40 years old and are at there limit now.

[260DET]

Standard suspension in good condition will be OK for a S130, just need a R200 diff to be sure, suitable tailshaft etc. Lowering it would be good but that will result in too much negative camber at the rear unless some mods are done there. Good spoiler, front splitter, undertray, rear wing or S30 type rear spoiler, rear diffuser.

 

S130 has good basic aero and as set up as above would be fine at 300kph.

[OZ001]

so ive tried 300km/hr but diff started making noises at 285km/hr slowed down and bang the diff blew... running a diff ratio of 4.11, towed the car home stripped it and it didnt look too pretty

[imackz]

so ive tried 300km/hr but diff started making noises at 285km/hr slowed down and bang the diff blew... running a diff ratio of 4.11, towed the car home stripped it and it didnt look too pretty

 

impressive @ 285 though, if you had a 3.7 diff you would be there..

[Riceburner]

This doesn't make sense to me, I really can't see the point of trying to get to a speed that you'll only ever see a few times. Where is this happening? From your first post it sounds like its on public roads.

 

For your sake and those other road users I hope your doing it in a controlled environment closed to the public or on a race track.

[OZ001]

This doesn't make sense to me, I really can't see the point of trying to get to a speed that you'll only ever see a few times. Where is this happening? From your first post it sounds like its on public roads.

 

For your sake and those other road users I hope your doing it in a controlled environment closed to the public or on a race track.

 

It's all good gareth, I had to have permission and a strict timings to use this area, wasn't easy and won't be using it constantly. Also not open to the public for any reason.

 

impressive @ 285 though, if you had a 3.7 diff you would be there..

 

Can't find anyone selling one at this stage, won't need it until another month till I can retest it. Back to the drawing board with the aero though, I had some lift going at about 240-250km. The steering became abit out of control towards 280km. Tyres were advan ad07 the last of many as i can't source out anymore. Anymore faster I don't think the tyres were gonna hold up.

[Patch]

You could always try a 9''or something other and do it like this.

[PeterAllen]

Like I stated back in reply #7, fit a GM (or Ford) diff.

 

Plenty of ratios to choose from, e.g. 3.07, 3.46. 3.73 or 3.91. All cheap as chips with CVs.