tonycharger72

What is the factory Zed scrub radius?

Thanks mate, Touch wood, should have the finished completely by the end of tomorrow, might paint them, but i wanna get into the gearbox crossmember asap, so i might wait, should have some more pics of the front of the engine and the clearances in the bay by the end of tomorrow,

http://album.hybridz.org/showgallery.php?cat=500&ppuser=12400 Ive almost finsihed the engine mounts for the 2JZGE into my 260z, they need a bit of cleaning up, but are almost done, there are some pics of the engine in the bay and pics of the engine mounts, What yall think?

JohnC thanks for that explanation mate, Just to clarify, are you saying that increasing the track both front and rear, but increasing the fronts by a larger proportion is what will give you the benefits listed from 1 to 4? It seems to me that it would be better to actually increase the factory track as basically i will end up with a better handling car, So why on earth is this bloke, who seems to know alot about Zeds, so deadset against changing the track in any way shape or form??? I still havent been able to 100% confirm exactly what the original offsets of the Zed wheels where, im pretty certain they started at 15+ for all the wheels on the 1970-78 zed's, JohnC you used 10" rims with a 5.5" backspace, so a 0 offset, so that is not a huge change in track from factory really, only 15mm (of course you used spacers which changed it further, not massively though) - even by law i can change my track some 27mm, you would imagine that the good folk at the RTA would set this 27mm limited because on a street driving car the cars steering characterics wouldnt be effected that dramatically by a 27mm increase/decrease in track??? This is the only real first hand experience ive had, 3 different sets of tyres & wheels on my Zed with stock steering and suspension components, 1 - 14 by 5.5 rims with 195/70-14 tyres (15+ offset rim) 2 - 14 by 7 rims with 195/65-14 tyres (15+) 3 - 17 by 7 rims with 205/40-17 tyres (20+) Options 1 & 2 pretty feel the same, but option3 was much different, low speed cornering was much easier, high speed turns felt like i was going to lose it alot sooner, under heavy braking i had to really hold the steering wheel tight to keep the car going in a straight line and in the wet she was slippery as hell - at 160-170kms/hr i didnt notice much of difference between any of them though

So using smaller width tyres so you can keep the track the same as factory, like use 8" rimms instead of going to 10-11" rims so as to not increase srub radius? Ive been looking at the 240zg a bit (nice looking car) and even if only 8" rimms were used, there is no way in hell that the ZG used factory offset rimms (ie....the same as the stock 240-260-280z's at 15+) they look like they have small negative offsets, which would cause quite a large change in track, and from what i know the 240zg is a factory car right? So if the good folk at Nissan do it to there zeds, assuming nothing eles has changed suspension and steering wise - does changing the track from say a 15+ offset to a -5 to 10 offset really alter the cars handling ability, or does it just change it, change it like - Just for an example (not what would actually happen) "now it handles better around corners, but doesnt have the same straight line stability as it did before" Or when doing the ZG with its large wheels and different track did Nissan also alter other suspension and steering characteristics of the car?

Was wondering if anyone is keen on getting there hands on a 280YZ kit, as show here, http://www.reactionresearch.com/280yzgallery.html Just if its bought in bulk there would be savings on shipping the stuff all the way to Australia, the more who buy, the less overall it will cost in Shipping, Anyone interested in Australia of getting one of these body kits with me?

I think the Rb25DET is the way to go just because its soooo much cheaper than the Rb26DET but can still get alot of power, Buy the Rb25DET Engine/Gearbox which goes for about $4000AUD approx, whereas RB26DETT's cost like $6000-$7000AUD for just the engine, and im almost certain that in this price range you would only be getting R32 Rb26's - not R33 & R34's (but i could be wrong), These engine/box prices are all import/wrecker's prices Then Just buy a Z31 Jap Spec Rear Rb20 sump and pickup, i got quoted about $520AUD for them from my local Nissan Dealer brand new, they were available, just had to wait a few weeks, as they were ordered from Japan and not on the shelf, then install on your Rb25DET and you now you got the sump in the right position, Im pretty certain that this sump will not fit on the RB26 and requires some modification, but it fits perfectly on the RB25 & 30, Then get engine mounts and gearbox crossmember from, http://www.rodshop.com.au/mounts.htm Down the bottom of the page, I was quoted about $250-$300AUD for the engine mounts and the Gearbox Crossmember, Only slight problem with this is that the gearbox crossmember they sell is used for a Rb20/30DET gearbox, not the monster Rb25DET gearbox (its alot thicker/wider), However, Ive been told by a Zed bloke in Melbourne that the crossmember still works, but to fit the Rb25DET gearbox in the Zed you have to remove the original Zed L6 transmission mounts inside the transmission tunnel for clearance, But on this, Im sure lots of folks out there have used Rb20DET/RB30ET 5-speeds and managed to get a healthy amount of power before they have broken the gearbox,

There is this Zed bloke in Aus ive spoken to a few times and hes just nuts about not changing the track on cars, says i will increase my srub radius which will cause the car, when it hits bumps, to track in the direction of the bumps, He gave 2 examples, Driving down a potholed road, right front tyre hits the pothole and the car veers rightward, & Driving down a straight at high speeds and the car can become unstable, wheels arent doing what the steering wheel is telling them to do, He just put the fear of god into me about making any changes in track from factory, JohnC, you only use the spacers to effect the cars steering characterisitics and not because of clearance issues? Just id be pretty keen to avoid spacers for clearance issues, because i want to get my car road registered and the local RTA folk frown upon them, Also curious, How much fun would it be driving around town with 10" wide wheels? would i need arms like the hulk???

Thanks for that RP95, i'd already removed my L6 and put the 2jzge into the zed, but i've got it sorted so all is well Tell you what though, was not the funnest way in the world to spend a few days of my life, Ive got the engine mounts made, now just got to do the gearbox crossmember, Also, that engine is a cool swap mate, looks really awesome, thats the later nissan V6 isnt it? the one that is a 90deg V6 which makes its narrower and easier to fit into the zed, unlike the VG30DET,

Wondering if anyone can help me with centering my engine & gearbox properly, Im in the process of installing a 2jzge into my zed and im having a bugger of a time figuring out whether or not the engine/gearbox are centred, The Chassis rails are 638mm when they narrow at the front and ive got a piece of wood in front of the engine, marked centre, which tells me that ive got the centre point at the front of the engine, But, How do i do the rear? Ive got under the car and tried to do the same with a piece of wood at the back of the gearbox, but the chassis rails have these bits of crud of them which makes it really difficult to get the 638mm piece of wood in place and centred correctly, Then - even when i manage this, it is really difficult to measure whether the exit point of the gearbox (where the tailshaft goes in) is in the centre of my piece of wood, as the gearbox is higher than my piece of wood by about 10cm's, doing it by eyesight just seems kinda dodgy, Anyone know any tricks or processes to make sure im getting the right alignment with my engine/box???

Ive seen folks that have 10" wide wheels on their Zeds who have to been running a large negative offset on the wheels for them to fit, ie........clear the spring perch, For example, You have a 10" wheel (=11" approx) with coilovers you can fit about 125mm (5") of the wheel underneath the car, the rest of it is poking out past the fender, So you end up running a large negative offset - like (-15), for the wheel to clear the spring perch, So the wheel offset would change from 15+(stock Zed) to -15 approx, This is a fairly large change in track, Im curious as to what kinds of effects this has on steering, suspension etc.....etc when you change the track this much, Does it have a different effect front and rear when you change the track???

Just curious, but i was thinking of using these calipers for my handbrake, http://www.wilwood.com/Products/001%2DCalipers/023-SFM/index.asp Do you think that these calipers could be spaced out to 25.4mm??? the site says they suit 3mm-9.6mm thick rotors, Anyone know anyone who has spaced them out to except a 1" thick rotor??? It looks like these are designed for it, but im not 100% certain, Also - was speaking to a local engineer and he said that instead of using a spot caliper i might think about using an internal type of handbrake setup - he was a bit sketchy on the details but he said it sits inside the rotor hat, Holden Commodores use something like this for their handbrake............. Also - Ive takin measurements on the rear brake assembly, from where the backing plate used to mount at the rear to the hub face and this worked out to be about 55mm, i just wanted to cross reference this with other folk to make sure this is what they got when they measured this distance

Hehehehe, Nah just tastes better

"If you know the diameter of the old springs and the diameter of the coilover springs, subtract the difference and divide by two" Dont you mean divide by 4??? Because - the spring is a circle, and when you increase/decrease diameter you would do it proportionally from all sides, For example, if you increased the spring diameter by 20mm - its not 10mm at the top and at the bottom, its 5mm top & bottom and 5mm left and right???

Just a quick question about coilovers, When you go to smaller OD adjustable coilovers, how much more space do you gain between the wheel and the spring perch??? Jags that run book says you get about 9.5mm - is that right??? or do you get more/less???

http://www.wilwood.com/Products/001-Calipers/012-FSL/index.asp Are these calipers Radial or Lug mount, dosent specifiy that i can see???

Ive done some more measuring, i spoke to SimmonsWheels Australia and they said i should measure from the rim and not the tyre for clearances, this is what i got at the fronts, Fender - 44mm to Rim (5" rim (152.4mm) from rim 25mm -Spring perch, Therefore have an overall space of 221.4mm, which means you run out of space to fit an 8" rim by 3.6mm, you need approx 225mm, There just aint enough room at the front for 8" rimms, unless you change offset and lip the guards, BUT................i have another question in regards to coilovers, If you run smaller OD coilovers - the JTR book says that you only increase you allowed space by 9.525mm approx (1/4" to 5/8"), and people have said that with 5" of backspacing on an 8" will fit within the guards and miss the spring perch, so according to my calculations......... 5" of BS = 225/2 = 112.5 + 15 = 127.5 = 5" of BS, Therefore an 8" rim with a 15+ positive offset would pretty much have 5" of BS, And the stock 5" rim has a 15+ positive offset, so the track does not change at all, the outside width increases directly proportional to the inside width of the larger 8" rim, So lets put in on the car with coilovers, Stock - 44mm clearance to fender 25mm clearance to Spring Perch 5" rim with 15+ offset means 91mm BS & 61mm FS, 8" - 91mm BS increases to 127.5mm (36.5mm) 61mm FS increases to 97.5mm (36.5mm) Clearance to fender (44 - 36.5 = 7.5mm) Clearance to Spring Perch (25-36.5 = -11.5mm) 8" & Coilovers - Clearance to fender (44 - 36.5 = 7.5mm), 10mm more clearance because of the reduced Outer diameter of the springs, therefore, Clearance to Spring Perch (35-36.5 = -1.5mm), Which means that if you kept the stock offset and went to 8" rims even with coilovers you would run out of space, from my calculations you would need to go to a slightly different offset - something like a 10+ positive offset for clearance, which means changing the track (although very minor change) This also means that you cant really put more than 125mm (which i guess is close enough to 5" of back spacing) under a Zed that has smaller OD coilovers, therefore if you run 9", 10" or 11" rimms you would need to increase the outside of the rim in a greater proportion than you would the inside of the rim, thus changing the track of the car - which ive been told is a bad thing, but lots of people seem to do this and drive some really really fast zeds...............

mmmmmmmm - im certainly no expert on this, but if you look at a stock 260z, the lower control arms arent horizontal, they go down towards the struts, i would imagine your best bet would be keeping this same relationship, This is what ive come across - the lower control arms travel in an arch, say for instance 15deg angle downwards and 15deg upwards (that might not be right, im just guessing), if you have the LCA horizontal you eliminate half of its allowed travel, which i dont think is a great thing, But if you lower the car as much as shown in the picture i dont think that would be possible to retain the same LCA angle as stock - but i could be wrong, If you do a search on this you will find alot of info on this site, alot of complex in-dept info If you buy the JRG V8 Conversion manual it has a step-by-step process of how to modify the cross-member and has pictures!!!

Check the last thread mate http://forums.hybridz.org/showthread.php?t=101841

Jsquared - thanks for that mate, Also a local 200sx guy told me that there was no difference between the s13 & s14 rear calipers,

I havent been able to track down a listing for the s14's - the DBA website only has listings for the S13 & S15, Ill have a look at some US sites, im sure they have a listing of the s14 rear rotors