jeromio

Background: rear susp. totally rebuilt, disc brakes, custom front diff mount, 280ZXT CV axles, 4.11 R200 (85 200SXT). Changed diff lube about 2k miles ago. This is a recent problem, first noticed it last week while driving in the rain. Acceleration even while moving causes the car to lurch to the side a bit. But decceleration makes it really step out in the rear - this is in a straight line, not cornering. If I push in the clutch, no lurch. If I hit the brakes, no lurch. If I ease off the throttle, no noticeable lurch. But if I am on the gas, and then let off quickly, the car does a little skip to the side in the rear. So, I thought at first that it was just b/c the roads were wet and I hadn't driven in the rain in awhile. But the next day the roads were dry and it still does this. I jacked up the car and the suspension is tight - nothing is amiss or askew. I have 0 degrees of toe and everything is good with the suspension. I can spin both rear wheels by hand. So then I turned on the motor and put it in gear. Only the right rear wheel spins. If I gun the throttle, the driver's side will spin a bit, but only a bit and then coasts to a stop. If I block the pass. side from turning, the driver's side will spin. Un-blocked, the right rear (pass. side) is the only wheel that will turn in every gear. While in gear, the pass. side is spinning, I can turn the driver's side wheel, but it's as if it has no connection to the drivetrain. This seems to be consistent with the issue I have. If I have one wheel drive, then engine deccel would act like braking on just one wheel and that could certainly cause the car to wig out. Unfortunately I am daily driving this car to work every day now. Pulling the diff is not an evening job. But assuming I can get it out this weekend, what should I look for? I am presuming it won't be obvious. I have another gearset (3.54), but it's been sitting out (really rusty). Plus, I doubt I have all the right shims, etc. Anybody have any experience with shops - what's the typical turn-around and cost? As to what would've caused this, I dunno. No drag racing, occasional stomping on the gas and burning tires. But I have 4K miles on the LS1. My wife has been driving the car lately - I suppose she could be maniacking it....? It seems to be a random onset problem, not an "oh ****, I just did something that broke something" kind of thing.

That was me - "old guy"? Ouch. There are some random pictures here: http://240z.jeromio.com/ac.html The 280 system doesn't bolt up as quick and easy as you might think. And the 240 dash is not super compatible. Most of the bolt holes line up - but not all. But it is a very compact system and it will fit. If I had it to do over again, and I may anyway, I would use an aftermarket system. I'm currently in the process of hooking up the LS1 compressor. And I bought an aftermarket condenser (the one that I got from the bone yard leaked like a s'ombee-ahtch).

What about this tool: You just drill a small dia. pilot hole and then attach the tool. It makes the bigger hole and flares it in one step. I would presume the cutting action would last longer than a holesaw. Worth the more than doubling in price? Also, as to the strength discussion, here's my (novice) take: there are many areas of the unibody where the sheet is merely acting as a cross piece. In other words, you could cut out the metal entirely and replace it with an X. Think tube frame. The flanging adds strength by stabilizing the material along its weak axes. Like putting a crease in a piece of paper: No crease, it flops; with crease, it can hold its own weight and more. You should check out the Grape software package for doing your cage layouts.

I think the track he plans to go to will have turns in it - NHRA rules not helpful there....

I have turned my front cross-member into a k-member. I have stock manifolds that exit to the rear of the block - no interference with the K's arms. I did the K to solve the LS1 mounting and accessory problems - chassis stiffening was just an added bonus.

No, I mean the condenser. I have a compressor. I bought the LS1 unit with bracket in hopes that it would fit - doesn't. So i am making a bracket, but the compressor will be located in the "stock" LS1 FBody location, passenger side low. BTW, there's plenty of room for the alternator down low - many inches to spare. I also bought an LS1 condenser, but of course it is too wide to fit. As I said, I could buy a new condenser that would fit, but with so many $20 used condensers to choose from, it just seems silly to spend $150.

So, I can buy a brand new condenser for between $100 and $200 that will fit. But it would be so much nicer to pay $10 or $20 for a used unit from some other car that meets the dimensional requirements. Has anyone dug around the salvage yard for condensers and found one that would fit an S30?

I have been daily driving my car for the past 8 weeks. I think I have already suffered some permanent hearing loss. The problem is that 65-70MPH (6th gear) translates to 1700-2000RPM. This is the magical sweet spot for my setup that produces brain scrambling drone. It's diving me crazy. My wife and co-workers are having to tell me to stop yelling - I don't realize I'm doing it. I have an LS1 (of course) with stock manifolds (sheet metal) to 2.5 inch tubes. These meet at a fat Y (slow transitions) 3 inch. this immediately feeds a 3 inch Dynomax Race Magnum Bullet Muffler. From there it stays at 3 inches all the way to a Mac Performance 3 inch offset to 3 inch center out muffler. Everything is mandrel bent. The addition of the bullet reduced the noise at idle slightly and seems to have taken some slight edge off the drone, but did not eliminate it. The Mac muffler is supposed to flow well. Perhaps it's just a crappy muffler (it's very pretty though - solid stainless - very heavy). It fills up the spot back there - of course it is small. I also have a 3 inch by 9 inch exhaust tip which is packed and perforated - though I doubt that is doing anything to the sound. My car sets off other car's alarms. And not just in parking decks - out in the open too. Wife drove the car the other day - I could hear her arriving home many many blocks before she pulled up. I've read pretty much every post here on the subject of noise. My next try will be car chemistry inserts. They're expensive though. If they don't work, I will cry, but no one will be able to hear me.

Well, I guess everything is trade-offs. Removing the Datsun towers allows way more room for accessories. At any rate, do you have any pics of the headers installed?

Did you bend it yourself? If so, what tool did you use?

Mine is run just like Dale's. You do need to clearance that bolt near the 11 o'clock position on the new idler though. The alternative is to replace that bolt with an allen head bolt, but I couldn't find one. The idler can be bought at a regular parts shop. My extra idler is just black plastic - not fancy billet like Dale's...

I'll have to double check with my shop manual, but I don't recall there being a different pump for the V6. The black doodad is a pressure sensor. In fact, I think it's identical to the MAP sensor on the LS1. For your number 6, If you don't want to just use hose clamps, it is possible to buy those funky fittings from the "regular" (as in, open nights and weekend, autozone) type parts stores. They're a bit pricey, but very easy to use - quick disconnect. $150 seems really high - I got my tank for $75. Actually, they cut the wires which gave me the plugs. But I didn't need them (I have the whole LS1 harness), so I threw them away . Which is odd, b/c I am normally a packrat. I do recommend replacing the hose that runs from pump to sender top. It's the funky bubbly tubing. I've had that burst on me - twice. First time I replaced the whole pump unit (ebay). Second time I used stainless braided line.

On my car (high hp LS1), I must be very careful of throttle application when cornering. I want to be able to apply some throttle post-apex, but too much (measured in like 1% increments) or too early and the back squirrels right out. When it's wet, this is all magnified. As it is now, this would make a fantastic drift car (not my intention btw). I have no rear bar. I'm using 150lb/in front, 175 lb/in rear. (BTW, I can't fathom what it's like to ride in a car with stiffer springs - mine's like a freakin' skateboard). I have the stock front bar and no rear bar. I have added front camber (lost my sheet - I think it's like 1.5*) due to relocated pivots (13/16" up and 1/4" out). I have 0 toe in back and about 0.5* toe in up front. Turn in is sharp. It also follows every road irregularity like a hound (235/45/17 Dunlops). It does not (to me) push. the tendency (again, butt dyno) is to oversteer. Overall, the handling is okay, but a bit twitchy. It's not an easy car to drive - requires effort. I'm wondering about this rear sway bar issue. I had a bar and was all set to fab up mounts, but read (on here and elsewhere) at the time some things that seemed to point to no bar as the way to go. Now I'm having second thoughts. I'm a total novice, so stability is the preference over speed. Ease of use is more important to me than corner-exit accel. I'm looking to upgrade the h/w up front, but for the rear, I'm really just trying to figure out the rear sway bar. The outsized power aspect of my car is a big issue. Would adding a rear bar make the situation worse? Adding the mounts will be no small task.

$500? Seems like it was cheaper when it was Tunercat....?

I suppose re-installing the datsun expansion tank up there would also help. This is partly why I wanted to put the filler up as high as possible. I think it would be ideal to have it even up as high as the little hole that has the Z emblem in it. But of course, that would mean routing tubing all thru the cabin to clear the well house.

Yes, except I want to use one of the flush mount type.

That filler cap looks sharp. I wish there was another way to route the filler hose to the FBody inlet. I used a 2nd gen Maxima filler since its angles seemed to line up well with the S30 openings. But it's still less than ideal. The "old" S30 filler was big and wide and you could easily get the filler nozzle in it, despite the fact that the filler is almost horizontal and has body-work right above it. With the modern, narrow filler, it's tough to get the filler nozzle in there - especially since most have that big shroud that's supposed to cover your filler and block excess fumes. And then the filler tube has to make this immediate harsh 90* bend, such that the tube is almost horizontal. Then there's another sharp bend into the tank inlet. I have to slow the flow to keep the auto-off of the gaspump from triggering. I think running vent lines from the filler neck back to the tank would help with that. But with the wheel house right there, I don't see many alternatives for routing. For instance, I'd like to seal up the stock filler door and create a new one up higher and forward more - but where would the tube route?

I am certain that my car could benefit from some professional suspension tuning. However, it does have stiff springs (coilovers), new shocks (Tokico), is lowered and rides on performance tires (235/45/17 SP5000). Before the dam (but after all susp. mods), the car was, IMO, not very stable above 80MPH. 100MPH was scary. With the dam, 80 is cake. With this mod - whatever function it is serving (air direction or dam stability) - it is even more stable at speed. Interestingly, my rear susp. used to be a total mess. There was a severe toe-in condition, I suspect a mis-aligned spindle pin bore from the factory. This condition didn't really bother me in the dry. But a little bit of water on the road and the car was completely un-driveable above 30MPH. I've since fixed it and it's fine in the rain, but I really am hard-pressed to find a difference in the dry. However, this dam, in both of its "stages", has produced very noticeable results.

Yes, it is a Poly dam - and it certainly flexes at speed. I hadn't thought of this mod helping to stiffen the dam. In my case, it's just a temporary deal - very thin sheet and it's only attached to the dam, not the car. I suppose it could be helping to stabilize the dam - but certainly not by much. I think the permanent mod would look like what bjhines has done with a piece of Al. BTW, my car is lowered and the flexibility of the poly dam has saved it (and me) several times when I inevitably and inadvertently get too close to a parking lot curb. And actually, when jacking the car I have to deform the dam to get the jack under the car (even though I paid extra for a low profile jack). So, a nice splitter is just not in my future.

Holly Springs. Just one 260Z and a 280Z 2+2. Couple of ZXs too. He has an ad on craigslist.

I will be starting the same project shortly. Or else I may punt and take it to the body shop. I got a complete rear quarter (passenger side) from a "junkyard" last weekend. In quotes b/c it was just some dude's yard with lots of crap cars in it. Paid $50 - panel has some rust spots. Took me 4 hours to pull. And I dented it in the process - minor though, I'm pretty sure I can push it back out. Anyway, as I was in the woods, I couldn't use my plasma - just the sawzall and grinder. Still, even with the plasma, I am worried about pulling the panel off my car. Any pointers? Job one is to clean up the donor part. I went wide and deep - took quite a bit of the car along with the panel. I'm going to wire wheel and blast it, then plasma off the extra bits. I'm especially curious about the wheel well area. Since I have part of this still attached to the donor panel, I will get to learn more about how best to remove panel from well. But does anyone, and MTennez in particular, have any insight into this? Didja just drill out the spot welds? The special irony of all this is that phase 2 of the body work project will be to flare the fenders, thus cutting up the freshly installed fender.....

I don't know about the rest of you, but before I put a front spoiler on my car, it would float at speeds over 80mph - terrifying. With the air dam, I can cruise comfortably at 80 and go as high as 110 before noticing any significant float. This weekend, I tried an experiment. There is a gap between the body work (the bottom of the radiator support) and the back lip of the dam (the back edge). Obviously air can flow back underneath the car via this large gap. So I took some plain thin sheet metal, trimmed it and screwed it down along this gap to cover it up. Now there is a sort of shelf. Pictures would help I'm sure, but if you're having a hard time visualizing: pre-mod, hood open, if I dropped something a few inches in front of the radiator, it would go straight to the ground. Post mod, there is metal from the front top edge of the airdam all the way to the radiator, so dropping something in front of the radiator will result in a clanging noise as it bounces off this sheet metal. Mine looks rather ugly currently - need to actually go back and actually make something permanent. However, the difference is noticeable. The car feels much more stable at 80MPH. I had it up to 100 this AM and it still felt very stable. It makes sense intuitively, and though I have no actual measurable proof, it does feel much better.

This has been discussed before, in particular the fact that bumpsteer is not always bad. In other words, that geometry is there on purpose, for a reason. But in terms of eliminating it, due to the nature of the problem, the spacers are not able to fully "fix" it - they affect a different aspect of the geometry, the bumpsteer curve is altered, not eliminated. Moving the pivot directly addresses the issue by moving those 2 lines closer to parallel. I modded my car with the xmember in place, but yeah, it would be easier with it out. I recommend spot/tack welding the washer to the hole(s), so you'd need a welder. Also, careful with moving the pivot out to increase camber. I did mine 1/4" out and camber changed quite a bit. I was also motivated by a desire to not hack up the LCA as much. As you move the pivot upwars, there is less room for the end of the arm to move, so moving it out helps (while also changing the suspension geometry).

Whoa! I disagree. Those are tiny little nuts welded to ~20ga sheet. It's also a spot that's prone to rust. My car's pass. side sway bar mount was quite corroded. True, you're closer to the center of mass and also you're into the actually boxed frame, but I would only use that spot if you first completely re-enforced that area.

That's not necessarily true. In theory, Ujoints will operate better if there is an angle b/c the bearings will roll (back and forth) and lubrication flow will be improved. But this is, as far as I can find, merely theory, subject to debate. For example, if the ujoint was truly mounted in a perfectly straight orientation, then it's not being "used" at all. Therefore, the bearings wouldn't roll and would not wear at all. Regardless, it's nice to see an update from Terry. He's like an engineering "found object" artist, making use of various junk-yard parts to achieve state of the art results.