TimZ

That's some nice work there. I do have a couple of comments... First - you are right - the ITB setups don't pull very much vacuum. However, if you sum the vacuum signals from all of the cylinders together, you will get a much better signal than your current setup does, especially at low rpm. It should be good enough to use a MAP sensor with - several others use this setup with success. Even if you decide to continue using TPS mapping, this setup will still give you much better vacuum to your brake booster. Second - what are you using for a fuel pressure regulator? It doesn't look like you are pressure referencing it (the only vacuum signal I see is going to the brake booster). This is apparently not an issue for you currently, as your system appears to be working. However, not pressure referencing the FPR severely limits the dynamic range of your fuel injectors - you will have the largest pressure drop across the injectors at idle, forcing you to use artifically low injector pulsewidths, and the pressure drop across the injectors will be at it's lowest at WOT, where you need it most. Additionally, not using a pressure reference will tend to give you inconsistent results, as a given injector pulsewidth will deliver different amounts of fuel depending on the engine's load.

Actually, I think it does pretty much the opposite of support - by definition it supplies a twisting moment to the unibody - that's it's job.

Before you start messing with the timing at WOT, do you know what your exhaust temps are? If the timing is to retarded, I would expect to see high EGTs. Also, I seriuously doubt that the 12;1 afr is causing any huge problems, and would recommend trying to lean it out much past that, at least not until you have a better understanding of what is going on. I'd be looking for breathing restrictions - the 2.5" exaust is suspect. Also, what size is the intercooler piping? How about the cam?

Sorry - you don't get to count the sway bar - it's not rigidly attached to the unibody.

Does the Profec have an overboost safety setting? My Hks EVC IV has this - whenever this setting is exceeded, it returns to the stock boost setting. Every time I up the boost setting, I have to make sure that the overboost sfety limit is set accordingly - 22 to 11 psi really feels like falling on your face...

Dyno tuning is generally only good for WOT. I can't remember what features the Mustang dynos have available, but if you were doing power runs (similar to what you would to on a DynoJet), you won't make much of a dent in your driveability problems. If you were able to set the Mustang dyno to maintain a constant load and speed then it's a different story, but most of the driveability stuff just requires some know-how and street tuning. Transient response is hard to get right on a dyno. ...and unless the dyno was in an environmental chamber, it won't do squat for cold start. What sensors are you using? I couldn't tell what you have and what you are doing without. Also, what cam are you running and how is it set up? On the poor gas mileage, what AFR are you running at cruise? Exhaust temps?

Have you tried rotating the tires front to rear?

FWIW, I had that same problem with the AZ Zcar brakes. I ground just enough off the end of the arm to clear the rotor, and have not had a problem since. That was back in, oh... about 1988... I had the problem without the bumpsteer spacers, btw. And its a 280 hub. The part that is ground off is all outboard of the ball joint, so I don't think it's adding much structurally.

I think the biggest issue for most people is that the price/performance ratio is way too low for the CF clutches. For medium-output L-series motors (~250lb-ft for the 220mm, maybe 300lb-ft for the 240mm clutch) they gererally work fine and do have acceptably low pedal efforts. You will have slippage problems if you go much past that. For about the same price as the CD-DF, I got a custom-made sintered iron disk/ACT heavy duty pressure plate that's good for 500lb-ft. The disk is a sprung hub one piece disk (stock style, not a pucked disk), and it works very well - pedal effort is higher than stock, but the release is very stock-like. I was even able to get it made with a Chevy-style WC-T5-splined hub. BTW, I got that setup from Clutch Specialties.

Great Job! This only reinforces my feeling that if I ever decide to replace my L-series with something else, the SR is the way that I would go. Parts readily available, lightweight, excellent power potential, if you go to forged internals you only have to buy FOUR of them, AND LOOK AT ALL THAT ROOM...

Ummm...not quite. Wideband O2 sensors are not simple 0 to 1 volt devices like their narrowband counterparts. They need specific interface circuitry to make them function, which will not be available in you PDA or laptop.

Something else to consider - most people that run 8" rear springs are running higher spring rates than that - higher rates generally limit the amount of suspension travel. Assuming you have Eibachs (the specs will be similar even if it's a different brand - the dimensions are dictated by physics), your rear springs have 5.33" of travel before they bind. For a ballpark number, let's assume your car weighs 2600lbs with you in it, and has 50/50 weight distribution. This would put 650lbs of force on each spring. which would compress your rears by (650lb)/(200lb/in) = 3.25 inches. This means that at your nominal ride height, you have 5.33 - 3.25 = 2.08 inches of suspension travel before your rear coils bind. If you've sectioned the struts by 1.5" and lowered it by the same amount, you should have ~3" of compression travel available from the suspension. So, it's very possible that your coils are binding before the suspension bottoms, which would explain why your aren't seeing marks on your bump stops.

F15 = my favorite aircraft - I was at the rollout ceremony for the first F15E (used to work at McDonnell-Douglas). Never got a ride though... As I recall, whenever the flight recorders show that that switch has been thrown, standard prcedure is to pull the engines and tear them down. That's a pretty expensive switch throw . Most likely worth every penny if you really needed it though.

What makes you think that adjustable coilovers have to have a bad ride?

Very impressive use of physics. A couple of observations, though... First, this only holds true if your injectors had gone static (i.e. 100% duty cycle and/or the MAF was pegged and no longer having an effect) to begin with at 10psi and remained so at 9psi. If the injectors are not static, then the ECU would probably decrease the fuel with the decreased airflow, and you'd be in the same place AFR-wise. The ECU might ignore the MAF above some boost level or throttle position (not sure on this) - if so, then the assumptions should hold. Second - it was nice to see such a thorough representation of the airflow, etc., but I think you made this a bit too hard. If you assume the injector duty cycle is the same in both cases, then you don't really need to know what the actual mass flow was - you just need to decrease it by ~4%. Since we are assuming that nothing else changed, the flow into the motor will be directly proportional to the manifold absolute pressure. So... (10 + 14.7)* (12.5/13) = 23.75 ...subtracting out 14.7psi for atmospheric pressure, you get 9.05psi. Now, neither of us take into account the fact that the compressor will be running a bit more efficiently at the lower boost level and the compressor outlet temp will be lower due to the lower boost pressure, so the actual airflow won't decrease by the full 4%. You could probably get a good idea of the extent of this effect with the with the above equations, although you'd need a compressor efficiency map to get that part. The math does get kind of ugly, though, since now you'd be solving for two equations and two unknowns (final boost, given outlet temp and airflow reduction required). I think it's safe to say that this effect won't be that big since we are only talking about a 4% change. Maybe go to 8.5psi just to be safe...

Before you try tapping that hole again, you need to go out and get a "bottoming" tap. This type of tap is not tapered on the end like a regular tap, and will cut threads all the way to the bottom of the hole.

Interestingly, my boss was one of the judges for this event. I was just talking with him about it last night. This was a monumental task, and it was not at all surprising that nobody made it that far. The level of sophistication required to make a vehicle that could navigate it's own way from Las Vegas to Los Angeles is orders of magnitude higher than any automated mass transit system currently in use. The contestants were not given the route until 2 hours before the race, and it consisted of about 2500 GPS waypoint coordinates that they had pass within some distance of to stay in the race. The vehicles are required to figure out how to get around whatever obstacles they might encounter on their own. The only external control allowed was for a kill switch so that is could be disabled if something went awry. While it doesn't surprise me that people with no exposure to this technology might underestimate the magnitude of the problem at hand, I did find it pretty amazing that several of the teams chose to make custom vehicles, instead of adding hardware to an already proven propulsion package. One team chose to add a special propane powertrain to their vehicle(I think it was a sand rail of some sort), and at the last minute figured out that they would not have enough range to make it on one tank. So they tore out the passenger seat and added a second propane tank. Apparently, this changed the suspension loading enough that their steering linkage started binding, and they couldn't even start the race. I just don't get it - why would you choose to add completely unneeded complexity to an already nearly impossible task? Then there was the guy that decided it would be cool to use an autonomously guided motorcycle. He spent pretty much all of his time f-ing around trying to get the thing to not fall over after 10 or 15 feet. It sounded like he didn't even start on the navigation stuff.

This was kind of my original point - I don't think it's possible to build a front cage in a Z that you couldn't hit your head on while seated. There isn't that much room there to begin with. Agreed. My intent in harping on this has always been to try to get people to think about what they are doing and whether it matches up with how they will actually use their car. Just because it works in a race car on a track doesn't automatically make it suitable for the street. Man - I've got to say that it is refreshing to see people able to carry on a debate logically and state thier opinions clearly without resorting to name-calling, etc. I participate in a couple of other forums, and this type of discourse seems to be pretty rare. Kudos to us

-10 here - I would not run anything smaller. I was actually considering running -12 lines.

I generally don't like water injection - too many things can go wrong, leaving you with way too much boost without the water. However, if you must run water injection, the aquamist is the only way to go. It's microprocessor controlled, 3D mapped, and has extensive failsafes capable of detecting an empty water tank, failed pump or clogged nozzle, and also capable of shutting down an electronic boost controller if something goes wrong. I've seen this run on a friend's car and was impressed.

Man - it's really nice to see that I'm not the only one that is concerned about the street cage issue. Regardless of where you fall on the issue, it's good to see that people are thinking about it. Several people have commented along the lines that it doesn't matter whether you hit your head on the steel cage or the steel door frame - metal is metal, right. I'd contend that this is dead wrong. It's not the material, but the shape of the material, it's proximity to your head, and how it's going to effect the motion of your head when it hits it. Shouldn't take a rocket scientist to see that there is a huge difference here. First off - the shape of the cage will most likely be a round bar. The convex shape if the bar will concentrate the energy that is transferred to your head to a very small area, and WILL do much more damage to an unprotected head than the more convex shape of the door frame/roof interface. Think about it - would you rather get hit in the head by a baseball bat or a tennis racquet (the flat side, not the edge )? Yes, at some point either one will kill you, but that point comes up much sooner with the bat. The idea of using square tubing will most likely be a better approach in this area, but I'd be very careful about the construction of such a cage. It has already been mentioned that such tubing isn't as strong as round tubing, and it will be even less so when you start trying to make it follow a curve, instead of using a straight piece. It would take some serious consideration to make sure that if the cage deforms it does so away from the occupants. The issue of proximity to the head should be pretty clear - as has already been pointed out, there isn't too much room in the Z's cockpit to begin with, and I have yet to see a solution that keeps the 'halo' section of the cage without encroaching into your head's normal range of motion. Just to add some anecdotal 'evidence' here - one of my development vehicles at work is a Lincoln Navigator. We anticipated having to do some limit handling work with the vehicle, so we outfitted it with a full cage, custom designed and installed by a VERY respected local fab/prototyping shop. Pretty much EVERY time this car gets driven on the street (it's about an hour's drive to get to the proving grounds), somebody inadvertently hits their head on the damned cage - often hard enough for the pain to be a major distraction to the driving tasks at hand. This is in a Lincoln Navigator being driven normally in normal city traffic, folks. If you think you have more headroom than that in your Z, you should really consider putting down that crack pipe. The other thing that makes me very nervous about the 'halo' section is that the section that goes across the headliner is often in a very bad location. I have seen many that are located such that during hard longitudinal decel a loosely belted (i.e., not using a racing harness) occupant's head will naturally contact the bar at right around the forehead area. The effect of this will most likely be to snap your head back severely and compress your spine. I won't sit here and argue that there aren't any situations where a full cage wouldn't help. However, it's patently clear (to me, at least) that there are many more situations where having a full cage on the street (where you almost certainly will not be using a full harness and helmet) is a liability.

What SpeedRacer said. Small detail on the bleeding order - because of the way the brake lines are routed, the left rear is actually the farthest from the MC, line length-wise. So, LR, RR, RF, LF