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Hi Cheef,I think you can see that is a high end drag race car.The suspension on that I would emagine is adjustable for damping and rebound,in other words once the springs have compressed the rebound resists the springs from de-compressing(might have made up a new word there lol)so keeps the weight over the rear wheels.Cheers.
 

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squat is always induced to transfer weight over the rear wheels, done with instant centres and centre of gravity with relation to suspension links and pick up points!!

so there!!

As the old fella says, its high end, so probably using a live axle and 4 bars or ladder bars, which are also desirable to get traction and weight displacement

Independsant rear end cars like skylines, cossies, bmw's etc are very difficult to get traction from, because to get grip you induce squat (soft springs and shocks etc) but as the rear squats, the wheels arc into the arches, which reduces the tyres footprint onto the road and producing more spin!!

ive done a lot of messing with this stuff, and read up a lot about it, but the subject is hugggggeeee, and lots ofphysics etc, but quite interesting really!

sorry i will get out more in the new year!!
 

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Hi convert,good topic this.To get a jap RWD car to run circa 10 secs is not easy and as you say solid axle ford/strange is the way to go with tubbed arches and full slicks(the way project GTST has gone).I think the supra is at the stage before this as GTST was.The suspension set up when it was running 10 secs is owned by an so.com member and I looked at buying it but it was to drag specific for me then.It is as I said adjustable for damping and rebound with a gas or liquid resevoir at each end of the coilover.It cost JB 4k in parts and Gary at GTArt says if they costed the labour to develop would be another 6k.These units are available from Strange but for there own or Ford axles which is why they are used on so many pro cars.Cheers.
 
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Quality info there. :cheers:

So there's a certain margin of error when tuning/setting suspension for optimal traction?
 

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Yep depends on track conditions and the last time it was glued.Most of the HKS drivers hate RWYB running with them as treaded tyres destroy the track prep by balling up the glued surface,they would rather have everyone on full slicks but is never going to happen.I did my best time on a test day at Pod(£60 for day )but the track is stickeyed regularly and most cars are on slicks.Cheers.
 

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it is interesting stuff, i have read more into the live axle stuff for my capri really, its hard to make informed decisions without cenntre of gravity locations and corner weights really, but still interesting

as for the 4x4 stuff, its a whole different ballpark, i know george Gtarrrrrrrrr has run tens, which in my book is unreal really, as its basically a stock layout car, i knw its uprated, but not rechassised etc, so absolutely stunning times, i was very pleased to get mine into the twelves, and think it would see 11's quite easily with a few tweaks, although i couldnt start to work out where to tweak it!! tyres first i suppose, then who knows!
 

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Yes,mine runs 12's best 12.03 and that was 2 years ago.That was with 750lb rear springs and M&H racemaster radials,and at a test day at Pod.Since then have changed to M/T street radials,bee r for launch and 275lb springs and can consistantly do 12.2's.Next is 150lb springs and line lock.From speaking to guys at Shakey if I give the tyres a good burn out it is worth agood .5 sec,we will see.This and with softer springs to improve my 60ft(av 2.2 now) I will do 11's next year.Cheers.
 

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Thanks for the comment wardy but why would I want to use track tyres when I use the best road legal drag tyres available.My problem is my car is a RWD drift/track car on a drag strip which is why I am using softer springs from what they were and am going softer still.When I had the 750lb springs I could spin up for 3/4 of the track.Cheers.
 

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Tried adding 60kg of bagged gravel in the boot on last RWYB of the year(still going cheap Tigger)and although I only got one run in had a couple of the pro guys watching and spun up as usual and av 60ft.Conclusion was softer springs and a good burn out.Cheers.
 

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i did a lot of practice launches that were observed in the capri which is fully stripped out, and i found slipping the clutch at launch cut the wheelspin significantly, as if setting off from a junction and then realising somethings coming, you cant nail it because of spin, so you feed the power in, cut my 60ft's considerably from sidestepping!

i still get substantial spin on each gearchange, on or off gas, and like you im still spinning the rears at 110 in 4th as i cross the line!! ive upped the tyres now though to a 265, and fancy some hoosiers or something thats street legal and semi slick with a soft wall, but im scared if i hook up better it will lunch the transmission or worse prop! once i get some better traction i hope to be able to use the nitrous right off the line and get into the twelves at least

the cars going to be backhalved eventually, but its a long job and i need to start to get some enjoyment instead of work out of it soon!! but it will get nice simple homebuilt ladder bars

as for burnouts git, im told unless you ar running the full slicks its no use, and that it is only to spin the pit crap out yer treads really, as the heat is lost by he time you launch, i certainly found no difference with or without on street tyres, better to start a drop the pressures 2psi at a time until you get the best launch and stop there really
 

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Hi convert,tried slipping the clutch but as its a OS twin plate its pretty much engaged or not.I know my car is never going to be mega quick but really enjoy racing it and have won a 6cyl RWYB (still don't know how lol).I use Miickey Thompson E/T street radials (255/50/16) and two of the guys in PSD have proved to me giving them a good burn works by the 60ft times they have acheived with or without burnout(have been down to 12 psi with tyres).My terminal speeds are 125/126 so I should be doing 11's all advice is welcome.Cheers.
 

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well if you find it works, then i suppose it depends on the tyres, never helped mine that i could see, maybe a few thousandths!! i was on 205 60 13 remoulds in fairness though!

its a good laugh, i cant afford to be competitive, but i will do anything that costs nothing or very little! I know i can back half the car for around £300 if i make the bars, brackets etc, it sounds easy, and it is, but it takes forever!

are you using any nitrous? assume not if you are using bee-r
 

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No Nitrous as until I can get grip sorted not much point.Someone told me Bee R and Nitrous did'nt work together ? Should have said the guys in PSD are using the same tyres as me.I suppose I am doing things on the cheap and looking for the biggest bang for the buck,but get the best advice I can and give it a go.My mate who's got the second quickest MR2 in thw world has told me the only real way to go to maximise the car is to run full slicks but want to keep it road legal.Keep the sugestions comming lol.Cheers.
 

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i really like the bike on the second link but wouldnt like to fall off it though lols
 
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