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I've been running the exact same unit in my car for about 4 years now... Works great as a defrost heater (but mine never had a smell to it, even when new). I was thinking about modifying to save extra weight by removing the large fan and replacing it with a high power cooling fan like those used in desktop computers. It may not flow as much air but I only need it for defrost anyway...

Are you talking about these? If so, I'm pretty sure thats what came with my rota RBRs. They dont fit over the front hubs.

I've definitely been reading a lot about this issue. I've tried a few of the tricks people have used to solve it (corvette o2s, header wrap around o2 sensor) but havent had any luck. I will run through checking the basics - plugs, wires, vacuum leaks, fuel pressure, etc in the next could days just to make sure my bases are covered but I'm starting to accept that I will probably have to swap back to shorty headers, or get a set of LC-1s and run them as narrowband sims...

Bit of a dissapointing update. We tried the wideband spot which was about 8 in farther back. It definitely cleaned up the narrowband waveform. Hoping for the best we moved the other bank's o2 sensor to similarly farther back position. Unfortunately there was no change. While the o2 sensor waveforms looks much smoother the car still exhibits the same symptoms. Some other observations: This problem is not load dependent - happens uphill, downhill, any gear always the same The problem is not throttle position dependent - it can happen at wot or minimal throttle the same The only thing that seems consistent is the rpm range that the problem occurs in - 1000-1800 Weve tried forever to fix it with the tune to the point that i have a hard time believing that this is a tuning issue.... but spark plugs? Wires? Coils? Injectors? Fuel pressure? It seems like if one of these was going wrong I'd feel it at high rpm too right? But the car runs awesome up top and only has issues 1000-18000 rpm so what the heck??

Right now that car has no DTCs. It was giving me the P0133 or P0153 (cant remember which) when I first had the exhaust made, before my tune. I'm not sure if the tuner disabled these codes or the sensors are working better but either way I'm not getting any more trouble codes Moving the sensor back 8" seems really far but I may be able to try it... I have a bung that is about 8-12" further down on one side of the exhaust that the tuner put in for their wideband. I will try putting one o2 sensor in the farther back position and comparing it to the closer positioned sensor on the opposite bank.

^ This. There is no reason to drive a Z car as a daily driver unless you simply want to. Almost any small to mid-size car will get better gas mileage than your truck. Almost any modern car will be safer and more (or at least equally) reliable than a Z. I wouldnt try to sell myself the idea that the Z makes "sense" to drive. Drive it because you want to, or dont, but I wouldnt try to rationalize it.

I'm not sure how far back is too far back. If my o2 sensors were placed any closer they would be placed in the individual cylinder runners... I imagine thats not really desirable either. The car already is tuned on speed density and unplugging the o2s definitely cures the issue that I'm having. However, I really dont like the solution to just remove the o2s and run open loop all the time. Especially given that that the motor is completely stock... I tried the corvette rear o2s last night. No difference. My last attempt will be to install a wideband instead of one of the o2s and have it simulate a narrowband output for my ECU. If I dont get better o2 readings I'm not sure what else to do but force the car to run open loop.

As part of this whole process my car was actually tuned to run on speed density alone. I believe this should ignore the MAF, so the dirtiness shouldnt be an issue. However, I will give this a try tonight just in case. I've been reading about LS1 o2 sensors and it seems like they arent all created equal. I know we tried putting new o2 sensors in the car before but I believe they were just stock replacement front o2s for the F-body. Some people have said that with long tubes you need to switch to Denso or Bosch corvette rear o2 sensors due to their higher sensitivity and higher wattage heating element. I may try switching to these in case it makes a difference...

I guess the picture isnt that great... My car has never had the rear o2 sensors, just the front ones.

The o2 sensors are located right in the middle of the collector. This is drivers side, other side is similar Sorry the photo is so wierd, it was dark in there...

I finally got my long tubes installed and had a shop weld up a full stainless exhaust. It all looks and sounds great but the car has seemed to develop a weird problem. Ever since installing the long tubes the car will stutter and lean pop. It only happens below 2000 rpm just at throttle tip in. Basically if youre cruising on the highway 55-70 mph and want to go a little bit faster the car will stumble. I've taken the car to a tuner and they have tried to tune it extensively both on MAF and speed density. We've also tried new o2 sensors. The problem is still there. The only time we can get it to go away is when we disconnect the o2 sensors entirely and dont allow it to go closed loop. I'm starting to run out of ideas as to what else to try. Is anyone else having any problems with their long tube headers? My best guess is that something is preventing the o2 sensors from getting accurate readings at low rpm, which can cause them to overcompensate and overly richen or lean out the car. At higher rpm this problem goes away. I've considered just tuning the car to run open loop but it seems like a poor solution, especially given the motor is completely stock. I've also wondered if switching to a more accurate wideband o2 sensor and using a simulated narrowband output will allow me to get more accurate afr readings to the ECU. Any one have any ideas?

The 370z had Yokohama Advan Neovas, one of the highest performance tires short of a racing slick. The 240z had Michelin pilot sport, an all season tire. Not really a comparison IMO. Still, cool video. Fun watching the driver drifting the Z around the 180 degree turn.

Street tires are 245/45-17 on 17x9.5s Race tires are 275/35-15 or 23.5x11-15 on 15x10s The clubs here also make you work half the time, thats pretty normal. I work and drive half the morning session, then work and drive half the afternoon session (pay twice too ). Its a lot of standing around watching cones but it gets me more seat time. Normally with just 3-5 runs (only the first 3 of which actually count toward your time according to SCCA) you are still learning the course and squeezing out the best lap you can. I'm not a nationally competitive driver so I have a hard time getting the best out of myself with only 3-5 runs (I'm working on improving this aspect of my driving). 5+ runs really lets me get familiar with the course layout, find the fastest line around the course, make any minor adjustments to the car, and put it all together for a good run.

Try watching some of the videos in this series. Your results may be different but the basic idea is covered pretty well. https://www.youtube.com/watch?v=pRhTUf9iaG4&list=FL1u1fCozi1Pde7abywz4zMA&index=23 Try to get lots of seat time. Most clubs have a "morning" and "afternoon" sessions. I dont run my car in a class or for points so I'm allowed to go drive both sessions to maximize my time in the car. This usually gets me 6-10 runs instead of just 3-5. Initially, when you try different things try to make them VERY different. For example instead of bleeding 2 lbs from your tires, bleed 5. Or dont turn the shocks down 1 click, try 2 or more. You might not be attuned enough to what the car is doing to notice the small differences. A large difference will be immediately noticable and will give you immediate positive or negative feedback.

I've been taking my car to a good local shop for alignments for several seasons now. They have good reputation with local racers and are cheap. I've always trusted their readings without much hesitation. Maybe this isnt the thread to have this discussion but I've always wondered why people DONT trust the measurements they get out of an alignment shop? I've seen the alignment machines and they dont look so complicated that it'd take a scientist to get good readings. I'm sure, as with anything else, if its possible to get things wrong people WILL get it wrong. It seems like a reputable shop that knows how to work their equipment will be preferable to having to take measurements with bubble levels/strings/plumb-bobs/whatever else people use to get their alignment right. Is this job that difficult to get right that we go through all this headache to ensure we get what we want? Where does the error factor in? I wouldnt much like to do my own alignments but will change my ways if shop computers/alignment machines are really that much prone to error.

As Cary mentioned there is a bit more to spring rates than just the weight of the car. Ideally you want to calculate the spring rate on a car based on a variety of factors - unsprung weight, motion ratio, target wheel rate, etc. The motion ratio of the rear multi-link suspension on a s13 is very different from the Mac-struts on a S30. I think this alone makes comparing spring rates of different cars relatively meaningless. Regarding the Mckinney kit, I've been running this kit on my car for a while now. Ride on the street is reasonable (for a car with all heim jointed suspension) and I've had several autox TTODs and usually finish in the top few cars against some stiff competition. The Megan shocks are far from the best and if youre building a perfect or nationally competitive car are probably not what you want, but they can be made to work well enough.

I have used both walbro and bosch, they both work fine. If you want to get technical, the bosch 044 pump flows much better, especially at these higher pressures. For fuel, I removed the factory fuel rail and used it as a guide for bending a new 3/8" hardline. Took like 10 minutes to bend the line and it mounted back into the stock mounts without an issues. I used rubber fuel injection rubber hose and fuel injection hose clamps and hose barb fittings as needed in places where I needed flexibility. The components were pretty cheap and can be replaced easily or re-routed if I choose to change the fuel system. It doesnt look fancy but its very functional.

Yakima

Trailer? Who needs a trailer? 4 15x10 wheels/tires, modest toolbox with essential tools and fluids, jack, and still room for a friend!

If you have adjustable LCAs I'd do what you said - set the camber plate at -2.5 and adjust out the LCA to get to -3.0. -3.0 front -2.5 rear is probably a pretty good place to start. -3.5 front -2.5 rear may be too large of a difference. Hopefully your tie rods do not end up too short... Regarding tire temps, I've never used infrared pyrometers on tires. The infared units only capture surface temps, which can change a lot as your car drives back to the pits and sits around. Pyrometers with a probe are typically used because it gets underneath the surface of the tire where the temps are more accurate and stable. Regardless of which gauge you use it may be good practice to measure the tire that has experience the highest load first, then do the others. After youre done measure the first tire again, this may give you a reading on how accurate your measurements really are based on how the tires are cooling.

What is your suspension setup? Do you have adjustable control arms? If not I would run the -3.5 setting in the front and the -2.5 setting in the rear (if you have radial tires, bias-ply take a lot less). Then use tire pressure to fine tune based on what the tires like and how the car's handling feels to you. Even with the LS motor my car would have a bit of steady state understeer, I would previously run a bit more pressure in the rear to correct this. This year I'm running 275 hoosier A6s I plan to start at -2.5 front, -2 rear camber and hope to correct this issue. I hear Hoosiers like a lot of camber (3+ degrees) but I drive my car on the street so I dont want to get too crazy.

I can definitely agree. The exclusivity is probably the sole reason I choose to keep my Z. I like having an older/different car from everyone else at the track. I also like that I can beat most cars with my older/different/beat up looking car. It makes it fun. It is all about what you want to do with the car. There are a few racers (talking autocross) local to me that drive all stock, or nearly stock, cars (something like a vette, miata, or an evo usually). They show up at the track, no trailer, no tools, nothing at all, and proceed to smoke all the guys with the trailers, the huge tires, the highly modified cars around the course and then go home before the "other" guys have had time to drive the car onto the trailer. It might be a different approach than a lot of people on this forum (myself included) might take but its pretty cool in its own way.

The Z06 completely stock (with the right tire) they can run low 11s, get top 5 TTOD regularly autocrossing, run with the fastest guys around the road course, and still be comfortable/reliable/affordable to drive on the street. You can pick one up for 20-30k... and they have power steering and real crash protection... My Z is fun but if I had to do it all over again (or if I wreck my Z) I'd just buy a z06. That or an EVO...

My only experience with hydroboost was with a local autocrosser that installed a hydroboost setup on his 600+ hp C4 vette. The first event pretty much every corner he came up to he would lock up the brakes, he complained about how difficult it was to modulate the brakes. It took him a long time to finally get used to the new brakes to where he was competitive again. Not trying to discourage you just saying it might take some re-learning to get back up to speed again Overall, this is a pretty neat project, I'll be very curious to see how it turns out. I've personally have never quite been happy with how little assist our brakes seem to give, at least compared to power brakes on newer cars.

Yes, it is hooked up and seems to work well enough to hold the car on a hill. Its not that great but if I adjusted the parking brake right I may be able to get it to lock the rears. To be honest I've never tried to use the parking brake to lock up the rears. I've never needed to use this method to make the rear come around...