260DET

Yeh, plus they would be heavier, bulkier and more prone to jamming. For what benefit?

Be interesting to see the lower plenum/manifold used to mount the Webers, the stock one is a messy design and hard to do anything with, looks like he made a new one. That could be a Holinger gearbox, I know they made Nissan rally ratio gearsets but have never seen one.

Looks like you are going to be the forum pioneer on this Frank Recall hearing that the Z31 had a modified sweep angle, never seen anything specific on that though.

Having got my lent copy of Competition Car Aerodynamics back, finally, there is a mention of using a diffuser design in the front undertray, will have to study that more to see if its a practical design for the Z.

If they come up to temp doing autocross then that should be no problem doing circuit laps, thanks B.

So did they get up to temperature B? And what would the air temp be about? They have a wear rate of 100 and I'm wondering if they are soft enough for five or so circuit laps, which would be more that what you do I guess.

That would be good D, the only thing that concerns me is that Nitto = Toyo and Toyo R888's are rubbish, different compound to the RA1 for some reason. RA1 is a second choice but they would have to be buffed.

We don't get these in AU so I'm looking for feedback on their circuit track performance. Not expecting them to be as fast as a Hoosier or Kumho, my Z is already faster than me so consistent performance over the life of the tyre is what's important. Looking at importing a set to replace the present Bridgestone RE55's which will cost ~ US$1900.00 for new ones

My speedo goes up to 300 KPH so obviously my Z is the fastest of the fast NB 300 KPH is somewhere around 185 MPH for the Imperialists

Aaaah MTC, you were around a few years ago when I was asking questions on this subject I'll be using a VG30DETT sump pan and oil pump pickup on my 33.

Ah that info fills in a blank, have seen them and wondered what they were for, they often incorporate strakes.

I understand how a diffuser works, the final drawing concerns the rear of a car where air flows out the back. If it couldn't the diffuser would not work. With a diffuser under the front of and in the middle of the car the air has no clear exit path like it does at the back, which is why I'm wondering how your undertray section works, the splitter part looks fine. Can't find any VR SC info on the www, did you personally see one and copy it to make yours? I'm just trying to square aero principles with your design to satisfy myself that it should do whats required if I use the concept to make one for my Z.

23zed, the sketch below, taken from the link I posted, appears to recommend a high front, low rear floor. It may be just the way he has done the sketch but I think he is illustrating a narrowing volume for the air as it moves rearwards. Which would speed up the air and lower its pressure. If that is right yours would still work but the effect would be limited to the area where the air comes under the splitter in a high speed/low pressure state.

Good to see some more posts on this topic, my car has developed a high speed understeer problem so I've been looking for some aero answers. Perhaps some dive plates on the front but they do not look like they would do much. This linked site has some basic aero info http://www.superhachi.com/theory/downforce/ For those who trailer their race cars and are worried about low front clearance, I have seen removeable splitters/air dams used. They can eg slide on to a couple of solid pin mounts and be retained with a few Dzus fasteners. 23zed, whats the theory behind your recessed undertray design? I'm thinking of doing something like that but with the recess immediately behind the splitter. Am not sure which way the floor should slope though. I was thinking from high at the front to low at the back but yours is the other way around.

I visited the AGP a few years ago but am not from around there so I have no local knowledge. Unless you want to sit in a stand all day, boring, be prepared to do a lot of walking to get around, so comfortable footware is a must.

Here is a S130 half cage, designed to be suitable for street use, no head high bars to beat your brains out in a crash. The only parts forward of the hoop are the two low side bars that angle down to the bottom of the floor just behind the A pillar. Car has been in use for a while now, no problems.

You would love that Lakeside circuit I go to Frank, its all about momentum and big balls, I'm a better builder than driver though. Yeh there is no reason at all why your suspension should not work great, just got to find the right man to valve those dampers. Keep us informed of how you go, Nurburgring, scarey fast

Hehe, my S130 came with one of those. $50? Noooo, its mine, all miiine

To save some weight my front ARB is a hollow one off a Cima, about 34mm in diameter. I almost wish I'd kept the stock rear suspension, just to play around with and get it right, I'm sure that doable with the S130. A good semi trailing rear end is fun on corner exit, the more you stick your boot into it the more it grips into power oversteer The M3 tarmac video is great for showing that, black lines on corner exit, whoo

1150 KG without me in it. Yeh I should have said 300 pounds rear wheel rate, instead of saying 'equivalent'. Car drives great on the circuit, there is nothing to change, its perfect. And I am a fussy bugger Will say it again - dampers,dampers,dampers............ EDIT: Mine has semi slicks for circuit laps, slicks require a different setup according to the guru who did my suspension. Euros do seem to generally use a relatively stiff suspension setup from what I've heard and seen, my (amateur) preference is to get the car sitting nicely without much body roll, pitch etc, using the lightest springs/ARBs that will do the job. And use no anti dive or anti squat.

Satisfied 680 user here, it has been good, cranks the engine fine, several times if necessary, even if the car has not been used for a month or two. Car does have a good size alternator and no after switch off drain sources, such as a fuel gauge though. Any constant drain even if small is not good for these types of batteries.

ARB = anti roll bar, check out the stickies at the Suspension section for general info. My car has 400 pound front springs and the equivalent of 300 at the rear, weighs 1240 KG with driver, BFG Gforce street tyres. As I said, its all in the dampers, can't emphasise that enough. Ride is firm but it does not jolt or bounce or shake my teeth loose See my signature video and

Remember the M3 BMW tarmac rally video, plenty of rear suspension movement there but, yes, it does have to be controlled movement. The rear needs to be a bit compliant to put the power down and grip, I'd look at a big front ARB and none on the rear, I hate rear ARB's for race purposes, different for drift cars. On spring rates, mine has 400's on the front and it rides quite well on the road. How come? Body has been seam welded and stiffened up, plus the dampers are valved correctly. It really pays to have top class dampers, valved by someone who knows what they are doing.

Yeh flow wise they look the same. The 33 one is a big expensive lump of a thing, plus the difference in lengths gives another option for pulley alignment if needed. Put it this way, I'll be using the Z32 one if possible.

While I think of it, a Z32 coolant pump bolts straight up to the 33 block, coolant passages align too. But the nose of the Z32 pump does not stick out as far forward as the 33 one's does, maybe the pulleys are dished differently or something. This of course is relevant to aligning the fan belt drive.