260DET

The engine is presently stock except for a hi-flow turbo, intercooler, 15psi boost, bigger injectors and MoTec engine management system. 220 RWHP and lots of low/mid range torque. Seeing that the spare engine is going to rebuilt, I was thinking about doing some modest mods. Maybe a 65mm throttle body and a stroker crank. Have heard that a crank from a Nissan Z24 engine will fit. Would that require different rods, pistons, sump? Any other tips or leads appreciated.

Fortuna Engineering Works P/L, 859 Beaudesert Road, Coopers Plains, Q. Phone 3277 5699.

If you want adjustable camber on the front, consider using weld in eccentric adjusters, particularly if you are going to relocate the pivot points anyway. Fortuna make such adjusters specifically for your car, they weld into the Xmember, cost around A$80 pair. On suspension travel as dictated by the length of the strut inserts, your proposed setup sound OK to me, although once again it depends on proposed use. I guess if the inserts are too short you may end up with insufficient droop, causing the inserts to top out when the wheel drops into a hole, etc. Loss of some bump travel can be compensated for by using firmer springs, which you apparently intend to do.

My last pair of linear type King springs cost around A$180 (US$95), progressives are more but imho are not required. Whiteline for one make custom sway bars, my front is 28mm dia, but adjustable. You can get aftermarket brackets and poly bushes to suit. Super Pro brand? But you will have to make heavier mounts to suit the new bracket holes spacing. Stock mounts are weak anyway.

Koni Sports are a good choice. Length would depend on your proposed ride height but perhaps a rule of thumb would be to use shocks shorter by the same amount as the ride height will be reduced. King springs are good and come in a big range. May be cheaper than Eicbachs. Agree that no rear sway bar with a big front bar is the way to go, particularly if you are going for more power. Spring rates depend on what you are going to do and how much suspension travel you end up with. For my road/track car I use 250 fronts, 300 rears which gives a firm ride but not excessively so imho.

According to DBA, their slotted rotors improve stopping power over their non-slotted in actual tests. About 5-10% from memory. The downside is that the pads will not last as long. DBA are a reputable company to my knowledge.

Just to add some more fear apparently rally zeds tend to crack the rear hub forging, across the two 'legs' that join the hub part to the strut housing. The crack usually starts where the handbrake cable bracket bolts on, the two holes tapped into the forging. Later models have a stronger forging though. Never heard of this problem with circuit racing cars.

Hmmm, mass confusion, lets try and settle this. Proposition: if springs are installed pre-loaded ie compressed on the strut removed from the car, then the effective spring rate is increased. Because, actual spring rate is determined by starting with the sring at its free length and then compressing it. The amount of load that a free length spring will bear before the spring compresses by a certain amount determines its rate. And, the more the spring is compressed the higher the amount of load it will bear. Ride height is determined by spring rate, and, the position of the spring on the strut. The higher up the strut the spring's bottom platform is, the higher the ride height. Of course it would be possible to use a spring of such a high rate that it would not compress at all under static load. In that case, any further increase in spring rate would not increase ride height. Now, is all the above correct, or...........?

Koni yellows (Sports?), adjustable rebound only, are a great value shock, for road or track. Can't get them for the first series Z here but others(?) will fit. May have to get the bump revalved. There was a big discussion on this topic a while ago.

Yep, all in the name of parity, Ford have been getting upset because they mostly lose. On the big camber, it works for them, they all have power steering and braking does not suffer unduly. Because the racing is so close, suspension setup is crucial on those cars.

DOT approved tyres have a numerical wear rating stamped onto the sidewall. Basically, the lower the number the stickier the tyre. From memory the Toyo RA1 is around 40 and they are quite a soft/sticky tyre. On the road, I found the RA1 ok except for some very occasional 'tramlining' or darting, although that could have been caused by having 2.5 negative front camber. But, for road use only, I would go for a road type tyre. There are some sticky ones out there, check the wear rating number.

Later models have heavier strut tubes. My guesstimation is that any suspension flex is more likely to occur around the wheel bearings, strut (shock) internal shaft and the suspension pivot points.

Going the hi-po 2WD route will keep you busy and broke enough as it is. Big brakes, stiffen up the body, R200 LSD, suspension mods....... Power? How much do you want to spend?

Have heard of someone using the entire Skline floorpan with running gear grafted onto a non 4WD Nissan. An enormous amount of work and cost, obviously. I'd guess that your starting point for such a job would be to compare the track and wheelbase of a Skyline with the recipient car.

These are a grooved slick type of racing tyre, street legal in Europe and Australia but not the US I believe. Anyway, has anyone tried them on the road/track? Opinions, compared with ?? Check them out at www.stuckey.com.au or at www.dunlop.co.nz

kalium99, call me on 3354 3204 if you want to have a look at the Zed. It is up on stands with the wheels off at present.

My guess is that they are breaking because for some reason their freedom to pivot up and down sufficiently at the front is being severely restricted. Check that all is right with their rear mounting setup.

My bet is on the IRS factor. Which may be another reason why no rear sway bar can be made to work well ie that setup allows each rear wheel to work fully independantly irrespective of the spring rates, whereas a sway bar ties them together to some degree.

Let me know if you ever are coming to Brisbane. But future changes are possible, there is a Haynes book by Simon McBeath, Competition Car Downforce, which looks interesting. It may be described on www.haynes.co.uk

Interesting. My mate's RB30ET engined car runs 300F/250R progressives, with a large front bar and NO rear bar. Ridden in it but not driven it, firm but comfortable on the road and it seems ok on a circuit track, not much body roll looking from the rear.

Circuit track timed laps mostly, although the car is driven to and from. It FELT better with a rear sway bar, but now it can be driven harder/faster through corners, particularly long sweepers, even though there is a bit more body roll.

Any particular reason for recommending toe OUT for the front, John? As you would know, the rule is that toe out tends to cause frontal instability. I believe that some toe out however may help reduce turn in understeer.

Running without a rear swaybar reduces any power on oversteer tendancy dramatically. Believe me, my rear bar has recently been consigned to the junk bin. Of course then you have to look at the spring rates, 250pound front, 300 rear are what mine are at present. But there are no absolute rules in the suspension game.

The stock 240 body/chassis is not particularly rigid so the more you improve the suspension the more that rigidity aspect becomes relevant as to further improvement.

With that sort of power I'd be looking at a fairly heavy, strongly mounted front swaybar on the front, and NO swaybar on the rear. A swaybar on the rear will help it ride flatter, but be prepared for the rear end to let go bigtime when you give it a bootful.