JMortensen

If you have a cammed L6, try to find a ZX 5 speed. The ratio thing is the same for the trans as for the diff as Phantom stated before. The ZX 5 speed has closer ratios so it won't drop you out of the powerband. The 280Z 5 speed is particularly bad in the 2-3 ratios if you have a narrow, higher rpm powerband. For turbos and probably V8's too that have lots of low end, a wider ratio tranny will do better. For the diff the best thing to do is figure out your tire size and work backwards from there figuring your top speed, highway rpms when cruising along, etc. Jon

The only people I personally know that run the button or puck clutches are the people who were told that it was cool (not meant to be an insult to you or anyone else, but that's a true statement). I'm SURE that there are those on this list that would fry my setup in a day. There are people here that NEED the button disks, but I'm also sure that they are just a handful of people. John Coffey always says that people overbuild their brakes. I disagree with him on that, but I do think people tend to overbuild their clutch. I had a Nissan master tech and 510 and Z guy as a roommate for a couple of years and he helped me put my car together the first time. I kept saying I wanted a badass clutch, and he convinced me to drive it stock until I had a problem, then upgrade as necessary. As far as upgrading, he always said to get a heavy pp and a stock disk (Paraut disk was what he always recommended). He was also the one that rebuilt my other friend's 200SXT that had the CF DF that ruined the thrust bearings, and he showed me the damaged caused by it. That turbo engine did not make enough power to slip the stock clutch after being rebuilt. All that damage for no gain whatsoever, and a hellacious chatter to boot. Not all of the advice that my ex-roommate gave me was that good, but I think that particular piece of advice is very good, and I think you're right that MOST people that have them don't need them. Oh, and the weakness of a stock clutch disk is the springs. If you've got big power and you're shifting hard but the clutch isn't slipping, the springs will give out first. If you have the disc out and the springs rattle, replace the disk. I can only imagine that the puck disks with springs must go bad in about a week, but I've never run one so I can't say for sure. Jon

I know that my retainers hit my valve stem seals with an aftermarket cam, springs, and retainers (490 lift cam and Schneider springs and retainers in my case). Do a search and you'll find a fairly recent post where options for this were discussed. You can use a Datsun A series seal, or a Ford 2.9L V6 seal. The Ford seal looked like the way to go IMO. Barring some kind of contact I can't think of a reason why this would happen. Since it has, you should probably replace them all, and these lower profile seals would be a good way to ensure that it doesn't happen again. You might want to take a close look at the valve stems and make sure they aren't all scratched up before you install the new seals. Jon

I think they just have a taller ride height.

Probably 100K if you're nice to a street clutch on a street car that is driven like a street car Bastaad. I had 50+ on my original clutch when it just wouldn't hold the power anymore because I switched to Mikunis. The clutch disk looked almost new (I switched about a week after putting on the triples). You can probably expect 1/2 that life or less if you are slipping the clutch to spool the turbo all the time. Occasionally won't hurt it too bad. BTW--I just looked up the Nissan Comp clutch and found it rated at 750 kg or 1650 lb. The stock 280 clutch is supposedly 550 lbs. The 50% stronger than stock ACT clutch which holds down my motor would be 775lbs. The "extreme" ACT is 85% stronger, so 1017 lb. So that means the Nissan Comp unit is over twice the clamping force of mine and 60% stronger than the ACT. Couple that with the comp bronze button clutch disk, WOW. That sucker would hold down 550 hp I bet... All of my 510 buddies run the Roadster comp pressure plate. Their pedals are STIFF and they all carry spare throwout forks, and I've seen the forks split on several occasions where the pivot ball is. I'm sure John is right that the Nissan Comp stuff works great on the track, but I sure as hell wouldn't want that in a street car. I wonder if it comes with a left leg only version of the ThighMaster... Jon

You can't shim the hat out. You could shim it in, but that would be a bad idea IMO and isn't what you want anyway. Same deal with the rotor. Sounds to me like you need to a. do what Dave says, b. mill the hats down .1" (sketchy and then they might not be true afterwards, and you'd have to have them anodized again), c. run the 280 hubs and make a new caliper bracket... EDIT--d. remove the bump steer spacer if that is what causes the interference. Bummer.

I was just thinking this thru and you'd probably need to shim the caliper out if you changed the hubs too. Not sure what the difference in the hubs is, but it might be more shimming than would be good/safe/preferable.

I thought John had already ground off the end of the control arm for clearance. Am I mistaken? I'd seriously consider the 280 hubs. They are slightly heavier, but if I'm right and they do have the offset needed, then that would be a preferable solution IMO. I just hesitate when you're talking about removing structure from the control arm. I don't honestly know how extraneous that material is, but it just seems like a bad idea to this non-engineer.

I think that is why Juan says to switch to 280 hubs. More offset. Jon

Can't wait to bolt them up and try not to flat spot my tires!!!

So what's the plan Amir? You gonna take up John's spot in the OTC? Looks like a screamer...

I bought a set of Matco taps and dies. Then I went to my machinist to do my last rebuild, and he said they were crap. Then again, he pays about $40 per tap. I paid $110 for the whole set on sale, and I'm not a machinist... Jon

Lemme just say what I've been able to glean so far, and say that I have no firsthand experience, because I've always dealt with the 240 suspension. The 280 sat higher than the 240 stock, but I couldn't say how much. The 240 rear struts that you get from Tokico are the same as the 240 front struts with a 2" spacer on them. So if Juan had the rears with a 3" spacer, then the difference in the tube is 1". If you take a regular 240 and drop it more than 2" then common practice is to section the strut tube. Likewise if you were to put that same tube in a 240 with a 240 hat (also shorter) then you'd be equally well off sectioning the strut if you went lower than 1" below stock 240 height. So IF the 240 hat is an inch shorter, and the tube is an inch shorter, you could drop the rear 2" by swapping in 240 stuff. But then you'd lose your stronger stub axles, and if you're going to section them, the process is the same so you'd be better off sectioning the 280 stuff and not having to swap stubs. Take that FWIW, Jon

Agreed. I have no doubt that my Z with triples is faster in the 1/4 than my old SU's were. And I'm sure that you are correct that you could choke off the trips to perform better than the SU's at low rpms. That's just not what they're good for. They're good for screaming at high rpms and scaring children with the giant sucking sound, I think you'd agree. I'd still love to see what Norm's car would do with properly set up triples. I bet he'd be a convert too. The real decision maker is racing or street driving IMO. EDIT--Norm, I'm not a 1/4 mile guy, but I did a Gtech test once with a badly slipping clutch and it said 108 trap speed with my buddy in the car (still not sure I believe that thing, that seems pretty high, but that's what it said). Did I mention I get 20 mpg on the highway...

The 280 tubes are longer.

If you're talking about slow corners where you come out of the corner at 2000 rpm, you would be the FIRST person who I've ever heard talk about getting a triple carb to do that better than an SU. This would include Rebello, Malvern Racing, Nissan Comp, and others I've talked to about making that situation better. ALL of them said that is the give and take with triples. You pay on the low end to get the top end. Maybe you're just that good, or maybe you haven't driven a Z with a properly setup set of SU's. Not sure. If you can tune them to be stronger there, that should be your business. SU's have an infinite number of jettings if you make your own needles and nozzles (every slightest bit of the taper change is a "jetting change" on an SU. Even the factory ones have 8 or more stages on the needles IIRC, so they still have more variation than the trips. WOT is WOT. Both the Mikunis and the SU's have a setting for it, and I don't think ANYONE would doubt that triples are going to kill SU's at WOT. Jon

Here's another potentially controversial statement about why SU's make better low end power. The oil dampened action of the pistons means that the holes that then engine sucks air through get larger slower. On triples, you've got 6 of the equivalent size holes to the SU's instead of 2, and when you slap the hammer down, all 6 butterflies open almost instantly. Intake velocity goes to 0 (or close) until the rpms come up enough to suck enough air for them to start working again. So at low end port velocity is bad and fuel atomization is bad, even if you have relatively small chokes in them. On the high end, no problems. This is why the SU's work better on the low end IMO. On the SU's the velocity is much higher at any engine speed but especially at low rpms, so the atomization of the fuel is much better at low rpms. The triples are more adjustable unless you grind needles and nozzles for your SU's, and IME once you get them set up they don't need a lot of tuning once they are on and set correctly unless you change altitude drastically or move from Florida to Wisonsin or something like that. I've heard differently about Webers, but this is in reference to Mikunis. Ed says that most people don't know how to tune their triples. This is exactly correct. That's why I said previously that if you know how to tune them great, but if not, then you'll either have to learn or pay someone who tells you that they know big bucks to do it, then hope that they have as much expertise as they said they did. I LOVE my triples, and I'd can't forsee any change in the SU's that would make me want to go back. It was a HUGE top end power increase on my car. But the SU's would be a better street carb IMO. Jon

So what's the solution? Getting ready to stitch weld the rear subframe and living in Seattle makes me interested... Jon

Gotta love silver

John, do you think the Blacks are too aggresive for autox? I'm looking for a pad that I can use for both. I know the Blacks need to heat up a little, but according to Hawk they only require 100* to start working. Sorry for the thread jack...

He's got net toe in on the back. So the car would crab very very slightly, and he won't get wear on the left rear from the toe IME. The rears are going to want to drive to the left, and the fronts are going to want to drive straight. I think he's got the tire wear problem down correctly. When he punches the gas, the rear squats and he's got more neg camber, then he's trying to put down 300+ hp to the inside edge of the tire.

Well you could use camber bushings to get more positive camber, but that's gonna suck around turns. How about leaving the camber alone and taking corners harder...

If you don't want to mess with the strut tops, then Tim is right. Camber bushings would be the cheapest way to do it. Adjustable control arms would also work, but I get a little nervous adjusting a lot of negative camber in with a threaded rod bearing the load. You probably wouldn't have to worry too much since you'd only adjust .3 degrees. You're actually within spec on the rear toe (total), but it is pointed off to the left a little. You can move it back to the center by slotting the holes in the uprights and sliding the transverse link to the left like Rick Johnson did, but that won't fix your camber. Camber is pretty damn close, I don't know that I would worry about it if this is a street car. .3* is not really very far off. HTH Jon

Man I HATE those adjustable bushings, in fact I'm going to great lengths to get rid of them. Have you considered trying to loosen the front and rear crossmembers in the back and retighten? I know John Coffey has also talked about putting shims in the bushing cups to move toe. The camber would be easily adjustable by slotting the holes in the strut towers. Just another option.

Poor man's camber plate (slot the holes). Jon