LeonV

At the very least, it should be vented to atmosphere. It would be better to devise a PCV system on the triples, as others have before (e.g. stonehenge from Zcar).

Did you check the differential strap which goes over the top of the diff nose? Make sure it's in good shape and not stretched out. Put in an RT mount for extra insurance.

That's exactly what I did on my 260Z. I'm using poly in front and the old rubber in back for the TC rods. I also don't have rubbing issues, but I have a lower air dam and not the factory valence. I was pleasantly surprised that I had zero rubbing with my setup, which is similar to your car: 16X7 Panasports with 225/50-16 rubber and Eibach springs. The ride is stiff and harsh, but that is mostly due to the very small amount of bump travel available before hitting the progressive bump stops and also the valving of the Tokico HP dampers. Some NVH analysis would be cool, I haven't seen that done with a Z!

Okay, that makes sense, regarding the subframe bushings. As far as putting in the rubber TC bushings, you'll notice a reduction in harshness which would be proportional to the spring rate change. You'll get a bit less noise, but I don't think the change in actual ride harshness will be drastic. I would try to devise a way to measure harshness and do back-to-back tests (accelerometer(s) perhaps).

Exactly. If the manual recommended 91 RON then 87 at the pump (AKI) will be fine. All the octane rating is, is a measure of knock resistance, meaning resistance to self-ignition under high temperature and pressure. It has nothing to do with burn rate, energy, etc.

So I take it that the engine always cranks over when you turn the key, but doesn't always start? My triple Weber start routine is this: Cold: pump pedal 3-4 times, crank over and hold at high idle for a bit (start enrichment not hooked up) Hot: ever so slightly hold the throttle open when cranking over, it starts in one crank when I do this You may have other issues, but try the simple stuff first.

Agreed!

I'll agree that stiff TC rod bushings add to ride harshness, but it's more to do with the fact that they limit vertical movement (adding to spring rate). This effect is exacerbated as TC bushings get stiffer. However, I disagree that all cars are designed to have the wheel move backwards much in bump. If this were true, all cars would have terrible bump-steer as rearward movement of a steered wheel leads to an effective change in tie-rod length. It is true, and I agree that passenger cars have some "compliance" built into them and if that's the give you speak of then I'll alter your analogy a bit. It is akin to catching a baseball with a stiff arm, with a glove on. If the glove has "give" or "compliance", then it will deflect more when catching that ball. When using a stiffer glove, you will "feel" the ball more, since there is less deflection in the glove (less force absorbed at impact). Maybe I'm just rephrasing what you meant, but I just wanted to be more clear on what I wanted to convey.

Don't bother, unless a head port is blocking off an intake port (opposite of your situation). Unless you plan to hog out the rest of your intake to match, you're not gaining anything.

I changed all of the bushings on my 260Z to polyurethane. Install was not bad in retrospect, but a big PITA while you're in the moment. Blue's Tech Tips has a nice guide on bushing replacement. As far as ride, I'm fine with it. The spring and damper choice has much more to do with harshness than putting in slightly stiffer bushings then stock. It's not like you're using metal bushings or heim joints. You'll probably get a bit more noise, but ride harshness shouldn't change much when compared to new rubber bushings. You are a lucky guy! I was looking to buy an M Coupe for months before finally going with an S2000 (my other top choice) recently. Those Coupes are awesome cars, but don't expect that a Z will corner and ride like one. A Z that corners flat will feel harsher, louder and more raw than an Coupe, even if it has coilovers.

Not a problem. I'm pretty busy these days, but I could probably manage to stop by sometime if you're having trouble. Feel free to PM me, or give me a call if you still have my number.

Syncronization should be done at idle, with all linkage disconnected. Once all throats are breathing equally, make sure all linkage bars are parallel to one another and install them one-by-one on the carbs, making sure at each step that airflow remains unaffected. Once all linkage is installed, check all throats again after giving some blips of the throttle. Airflow should be even. The very last part of syncronization is bringing up the engine to a high-idle (get a helper or hold the linkage by hand, Weber STE makes this process simpler) and checking sync. If it's off, then you have a linkage problem. Sorry for the aside, but I thought it would be a worthy tidbit.

Point well illustrated. I've been noticing the trend as well, but did not realize the scope. US Zs coming into the world market will definitely make their value go up if more and more Zs get shipped overeseas. Interesting...

Yes, it'll work just fine.

I'll just stick my head through the door and add that it's funny when the "rev-happiness" of the L24 is mentioned and compared to the less rev-happy L28. The reason for this is the cam, not the bottom end! Put in a bigger cam in an L28 and it will love to rev. That is all, back to my cave I go.

Nice, post some pics (Porsche and Z)!

Yoshi, this is Leon, the guy that sold you the carbs. I ran these on my first 240Z with the emissions stuff plugged off. The emissions hoses were cracked and old, and there was no AIR pump to be found on that car, so I decided to plug them off as to alleviate some vacuum leaks. The PCV valve should still be in the balance tube, all you have to do is connect your block breather tube, located underneath the distributor to the PCV valve. The flow guide valve hoses should be easy to hook up as well, reference the manual. [EDIT: I think one hose goes to the block breather and the other to the air cleaner, but I'm not 100% on that.] The throttle opener is currently not hooked up, but you could if you wanted to. I rarely drove the car and didn't see a need to make it work, but you could if you wanted to, again the manual will show how it goes (remember to reference '72 and older manuals). If you don't have an AIR pump, and your AIR gallery is not functional or present, then you obviously will not be using the AIR system. There are no provisions for EGR with these carbs, although I suppose you can make that work if you wanted to by using the flat-top balance tube. Good luck and let me know if you run into any problems!

You had trouble keeping engine speed consistent at idle, or were you doing a higher-speed syncronization?

Have you taken off the filters to see if you can spot the culprit? Loose venturis will demonstrate these symptoms. If the venturis all check out, run the car with the filters off and observe. I always keep an extinguisher nearby when doing any sort of fuel-related work.

Interesting, let us know how this turns out.

If you can comfortably put your hand on the carbs after hard driving, you don't have a heak-soak problem. I'd be surprised if your carbs got very hot with header wrap and a heat shield. Do you have rubber isolators between the carbs and manifold?

...here comes Idiocracy! The turbo has electrolytes. It's what cars crave.

Why would you do only the front? You will have a terrible ride and handling if you have a stiffer, lowering spring in front and a soft, stock spring in the back. That's a lose-lose in my book. All else you seek can be found with a quick search, perhaps with key words such as "Tokico", "springs", "lowering", etc.

So you're saying that if I were to fully restore a Z and decide to sell it, I should sell it for $6k just to keep prices reasonable? That's pretty unreasonable. Supply and demand is exactly it. I can put my 260Z on ebay right now with a starting bid of $50,000. This does not mean that anyone will buy it, nor does it mean that it automatically raises the prices of other cars. If you're not willing to pay $5,500 for an automatic 240Z with a locked up engine, and nobody else is, then the price of that Z will drop because it is not in line with the value of the car. Value is determined by the buyers (market), not the sellers. If you want to keep the prices of Z-cars down, then don't buy expensive ones. However, don't be surprised when somebody else scoops up a nice Z for more than you thought it was worth.

Obligatory question: have you checked plugs/wires/cap/rotor?