kyle

Sumbitch! Took it for a nice romp yesterday, filled it with gas, all was well. Weather's decent today, figured I'd take it to work. About 2.5 miles into the 3 mile commute, #2 quit on me. That's why I thought I should replace all six! Grrr....

Hi again, hope everyone is happily sleeping off a turkey hangover. Checked the plugs, 19/13/13/14/15/16 K Ohm 1-6 respectively. Cleaned the cap terminals, pretty corroded, regapped the plugs to 39 from 45 or 50, and still has a miss. Then inspiration struck! Miss is most noticeable under a load... and sadly lacking a dyno in my garage, how to put a load on the old thing? OOH! How about this York AC, that sucker is a load and a half. With that figured out, the #6 cylinder, though firing about as well as the others, wasn't pulling its weight. Swapped the wires, still #6. Swapped plugs, now #5 is out. So, once again, I have a plug that looks good, doesn't carbon up, appears to fire, but just isn't. Whattya make of that?

As far as electronics go, I have the hall sensor and the HEI module, and a CD player, never listen to the AM/FM radio. Resistor or no? I had one plug that would foul and just not fire, no matter how often I cleaned and gapped it. After much tearing of hair, I replaced the plug, and it was fine. That suggested that the plug could be bad internally, and not have an external fault I could fix. Buy that? Before that one plug, the plugs did not foul at all... and the set I have now aren't fouled at all. I think the fuel is pretty close, other than a minor seasonal tweak and adjustment. The wires "were" new, and have very little use on them; can I just check resistance with a DVOM and see if they're all about the same resistance? Put it back together and run it in the dark, see if one's arcing? Prior to pulling the plugs, I pulled the wires one at a time at the cap, and had a very large spark from each. No notable difference in the engine's running on the removal of any of them. But it's still got a miss! Hard to tell at idle with the cam, it's fairly lumpy sounding. But once the throttle is opened, it's pretty obvious. Maybe the thing to do is to hold the throttle open so the miss is obvious, then check for power balance. Haven't monkeyed with the carbs in a bit, I guess something could be up with them balance or adjustment wise, but my money's on the ignition. Thanks for any clues or pointers, guys!

Thank you for the reassurance!

Hi all - You know the phrase, "I've forgotten more about "X" than you'll ever know"? Well, I don't know about the second part, but I do know about the first. I've feel like I've forgotten what sort of spark plugs to put in my engine. CRAZY! Since restoring/rebuilding eight years ago, I've put all of about 3000 miles on my Z. It's on the same set of plugs, and it seems that beadblasting them clean when they foul isn't a viable long term choice. (Don't worry, I clean them off before reinstalling, I'm crazy, but not that crazy.) Anyway, the plugs aren't fouled to look at now, but it's got a miss. 72 SUs/SM needles GM HEI ignition in 76 dist NGK wires N42/mild port/polish Cam is a 2002 (.480/274) IIRC L28 +1mm Flat top pistons/2mm head gasket, should be 9.0 or 9.5:1, can't remember. MSA 6->2 header/2.5" exhaust. Balanced internals and AL flywheel Went to Kragen for a set of NGK BPR6ES, or maybe '7's, and they didn't have'm. Then it turns out they have different specs for L24 and L28E engines. Any suggestions? Don't want to change to a different plug just because some outdated computer tells the underqualified counterperson what I should use. Car sits a lot, gets driven spiritedly when it does though, but OTOH, lots of short little trips as well.

The angle between the LCA and TC rod will change slightly with the adjustment of those parts. Having bolts there allows a small range of attachment. Really, though, why make them one piece anyway? What does it help?

The springs are black... heh, by now, everything under the car is black. Agreed, John, that the ride harshness comes from the struts; pretty sure the carts are only rebound adjustable (isn't that SOP for inexpensive adjustables?) But if I back them off, the car bounces like a ricer on the bumpstops... Heck, though, it's easy enough to try. Thanks for the input, guys.

Anyone know what the ST spring rates are? I bought them from Marc Sayer (if anyone remembers him) about 14 years ago +/-. I've searched about from time to time, but never found anything. I ask because this thing beats me the hell up. Took it out for a drive yesterday, and good golly, I was sore after a forty minute spirited drive on some nasty chewed up roads. FWIW, the car has 215/60R15 Michelins, full PU bushings. My struts are KYB 4-way adjustables, which were NLA when I bought them 14 years ago. To prevent riceboy oscillation, I have them set at full stiff front, 3/4 on the rear. I continually debate with myself the wisdom of investing in coilovers/camber plates (biscuits)/struts for a car whose brakes are borderline anyway.... seems like I'm looking at $1000 for suspension and $1500 for brakes. $2500 buys a lot of go fast parts for my Miata. At any rate, turn-in sucks, overall balance is not too bad, a touch understeery, overall grip is excellent considering the crappy tires, but the ride is miserable. Thanks for any input, guys!

Hi John- looks like you're suggesting -.25 to -.5 more camber in the front. I lack adjustability, but do not lack a drill; planning to relocate the lca pivot for the camber. What sway bars are you factoring in to those camber numbers?

You can get Porterfield R4 and R4s too.

fixed, sorry about the error. Agreed that the IT guys know their biz - frightening to read about having stacks of rotors, drums, shoes, pads, and three ducts per wheel.

I run FSBCs with HP+/ATE200/SS lines/ducts on my 240Z. I've had some issues with the rears (common), but the fronts have served very very well. You have to run the ducting up pretty high to keep from squishing it between the tire and frame rail. When I began improving the brakes, it was pointed out that ducting with non-vented rotors wouldn't do much good, unless "steps" were taken - like preith says, hats for the calipers or rotors, or the FSBCs.

And just to keep bumping my own thread, it looks like the front vented set can be done for $350 F and $450 rear, or $300 for the ZX rears. Before I go nuts and start buying things - has anyone done the vented fronts with 15" Panasports?

Well shiver me timbers. Those IT nuts use the Ebrake to take slop out of the rears during a race. That's so crazy it just might work. Maybe I'll run it up to Reno Fernely in October and see if I can make it behave...

Really appreciate the feedback, guys. My car is somewhere between garage queen and neglected completed project car. It's found a niche as an track day car. I have a BLAST with it, which is interesting given its non-sexy suspension and tires. It's too fast and too fun to drive on the street... gets to 90mph WAY too easily; short version is the lack of an Ebrake is a non-issue. The sticking point is that good ole slippery slope. $300 for a JY ZX swap. Easy enough to rationalize the upgrade to the $500 SX setup. Hell, then I'm pretty close to $750 for the Wilwood for the rears. Dunno what the vented 4x4 setup costs, but I'd guess $300 with new pads. Again, a smallish step to the $750 Wilwoods. But now, the $300 upgrade winds up being $1500. Sure, but now I've got the brakes to support a turbo ($3000). And hell, that's $4500 into a $12000 restored car. $4500 could go a long way toward building a turbo Miata or other dedicated track beater. Sigh... Short short version is I'm not limited by class rules, just limited by $$$-restraint, mostly spousal-imposed. But since she runs our stock Miata on track days, I can't beat her up too badly, can I? //edit, I should add that with full interior, sound deadening, piston-style AC, and stereo, I'm not super worried about weight. I just don't want to spend $800 for vented/ZX setup and wish I'd ponied up the money for the Wilwoods.