Zmanco

Does your P90 head have solid or hydraulic lifters?

That's a good suggestion, but only 1 of the hoses is listed, and it's $43. I think it will be easier and cheaper to just use some generic vacuum hose.

Sorry about the messed up link. I thought I had tested it, but it's too late now to go back and edit it. BTW, glad you're coming. We're still working on the drives, but hope to have 2 drives that capture the flavor of Colorado. The Sunday one will likely be for those who opted for the track event on Saturday. BTW2, I had a chance to drive our new track - not at speed -and it's going to be a great one. There are lots of elevation changes including some blind corner entries. And as you'd expect of a brand new track, the pavement is very smooth. There's also a link to some "faster" laps taken in a Z06 by Arie Luyendyk Sr.

This question has been asked and discussed many times. You don't even have to search - just read the stickies at the top of the L6 section. Then search and you'll find a wealth of additional information. That will probably leave you with a few questions, but they'll be intelligent questions and will likely be well-received. Right now it seems like you're not making much of an effort to teach yourself, and that doesn't go over very well here.

This is from MSII/E documentation: http://www.msextra.com/ms2extra/MS2-Extra_Gen_Ignition.htm#ignsets. I believe this was taken straight from MSII. FWIW, I'm running MSII/E driving an MSD Blaster coil on my 73 with the stock tachometer. Today I tweaked the tach adjustment on the back to get it to match the MS display on megatune, and then ran a datalog where I took the tach up to 7k rpm. The datalog shows about the same rpm (there's a bit of noise at that speed). So there doesn't seem to be any problem with the stock tach accurately reading the pulses as they get shorter at higher rpm.

I thought I'd find this searching, but so far can't. I'm going to replace a friends' brake vacuum hose between the intake manifold and the booster and understand that the preformed hoses are NLA for the 240Z (his is a 73). What is the ID of the hose? I figure I can get some generic hose at the local part store.

That's the setup I'm running and I have been very happy with it. But, there is one issue you should know. Even with the prop valve all the way open, the fronts will lock up first if you use the same pad materials front and rear. While that's safer than the opposite, you'd be surprised how much braking performance you're leaving on the table. With advice from this forum, I went with a pad in the rear with a higher coefficient of friction and now I will lock the rear first with the prop valve all the way open, meaning I can tune with the prop valve to get optimum safe braking. I was quite surprised how much of an improvement in deceleration there was at the limit. Also, as was said earlier, while you're focusing on the brake hardware, don't forget about the tires. They have a greater impact on stopping distance than the brakes themselves, at least for the first stop.

500 cc injectors on a NA L6?????

I found that most were best tightened using a deep socket and a universal joint. For a few, you may find it easier to use a closed end wrench due to clearance issues. Also, you may find that you need to be careful with how you position the header against the ports of the head before you tighten it. I have one of MSA's older 6-1 headers and the flange is rather poorly cut. The result is that I have to lift the header up off the studs before tightening to ensure that none of the corners of the port are left exposed and leak. The 2 center exhaust ports are the most sensitive to position as the flange is angled on the sides.

Sounds very nice ... except for the tapping sound. Sounds like a valve out of adjustment, or perhaps an exhaust leak? You didn't say what you thought of the sound and loudness. What's it like at speed? I've read others say there's a drone in the 2500 rpm range.

Since I posted this I've converted to MS directly driving the coil (removed the MSD box). 3.5 ms is fine, if a little on the high side based on my limited experience so far. My car is running fine with 3.0 ms. In any event, I don't think this setting is the cause of your problems.

aziza z, it's obvious that you're becoming frustrated and discouraged, and that's understandable, to a certain extent. And if you decide to give up on MS, that's your choice, and as mobythevan says, it's a shame. But if you're still game, I think a few of us are still willing to coach you through this. But in order for that to work, you'll have to give us more info. For example, in my last post I suggested a few changes to get you on a track that will result in a tune that you can live with. After a week we haven't heard anything back except last night's rather cryptic post. Remember, those of us reading this thread can't see you or your car. We only know what you post. We can sometimes make educated guesses about likely errors based on our own experiences (errors). But we need clues. I expect it will be a new day when you read this, and if you're game to continue, then give us some more info and we'll see what we can do to help.

Do a simple mind experiment: let's assume you put the prop valve in the front brake circuit. Then imagine you're at high speed and need to brake hard. As you press harder on the brake pedal, the pressure in the front and rear circuits begin to rise. Weight transfers forward putting more load on the front tires and less on the rears. But at some point (determined by the setting of the prop valve) the pressure in the front circuit begins to rise more slowly than the rear. Think about what's happening here: you're taking braking AWAY from the front end where there's the most braking capability. This more or less ensures that the rear brakes will lock up first, which is exactly the opposite of what you're trying to accomplish. Like others have said, prop valves only go in the rear brake circuit.

Are you're suggesting using an N42 head for a turbo application? If so, it's probably not a good idea as the N42 is an open chamber design with less quench than the P90 and P79 meaning you can't run as much timing as you will want. I've know people have made it work, but it's not the best choice. But why not go with what you originally suggested to get the head on the turbo motor (assuming it's a P90) checked out and cleaned up if it needs it? Changing a head gasket, especially when the engine is already out, is not a big deal.

When I converted to FI on my 73 I had to add a 3/8" return line. I bought a "roll" of metal line and roughly laid it out following along the factory metal fuel line. I used high quality (NOT HF!) nylon cable ties to tie the new line to the old. At first I thought this was only going to be a temporary solution and I'd switch to some metal mounts with rubber isolators later, but it's been almost 2 years now and every time I've check the fuel line and cable ties they're all in great shape and not showing any signs of rubbing wear etc. The hardest part was bending the metal line and not kinking it, but the advantage is that it's all one piece from just in front of the fuel tank all the way up into the engine compartment. I figured that in the event of an accident/collision, having routed it along side the factory line would be the safest. And it's reasonably well tucked up out of the way of rocks etc that might be kicked up while driving. Again, it's no worse than the factory line.

Going back to Grim's original questions, for the world in which we live, classical Newtonian physics works just fine. It's only when one goes really fast, or goes really small, that the effects of things such as Relativity begin to matter. Read more at: http://en.wikipedia.org/wiki/Classical_mechanics and scroll down to Limits of Validity. For more on Gravity, read http://en.wikipedia.org/wiki/Gravity and scroll down to "Earth's gravity". I have that History Channel show recorded but haven't watched it yet. But based on other History Channel shows I've seen, it's a good idea to question what they "teach". There are much better sources, even for non-scientists. For example, I'll second the suggestion to read Stephen Hawking's "A Brief History of Time". He's a very smart guy who does a pretty good job of explaining complex subjects in reasonable terms. If nothing else, it will get you thinking!

Regarding his friend RJ who speaks Japanese: "He's intelliger than you ..." What language is that: Ebonics?

I think the issue comes from the fact that the STOCK valve train (along with the rest of the L engine) is quite robust and one can pretty much throw any combination of STOCK parts together and expect it to live for a long time. However, as people leave stock behind they don't always realize they need to do their homework, and then find out the hard way about things like wipe patterns, ZDDP, etc. I was nearly one of them myself.

They are 16x7 zero offset.

Here are a few shots where I tried to show how the tire is in relation to the top of the fender. As for your question if it will rub with flares, I obviously don't have flares, but I did have to cut the inside lip of the fender. FYI, with the ES100s, they rubbed so rarely that I left the fenders alone. It was when I went with the wider Kumho MX that I had to cut.

225/50-16 fits very well and is pretty close to the stock diameter so you won't have to change the speedo gear. I wouldn't go wider with a 7" rim. I have the 16x7 panasports with that size tire and only had mild rubbing with the rear fenders. Fronts were fine. I have noticed that the width of the tire will vary a little between the various manufacturers. For example, I had Yokohama ES100s in that size with only an occasional rub when hitting a big bump. Then I tried Kumho MX and it rubbed more often. Now I have the Dunlop Direzza Sport Z1 Star Spec and they're just a little wider than the Kumho. Side note: you didn't ask, but of the 3, the Dunlops are by far the best track tire, followed closely by the Kumho. But if you need to drive in the wet, the Yok ES100 was the safest of the 3.

I'll chime in that 4 years ago I went the machining route to get down to 16.5 lbs and have been very happy with it. I have no issues with stalling etc. That said, when I did it, the Fidenzas were going for over $400 and I spent around $150 and several hours driving between machine shop and balancing shop. If I was to do it again today, I'd keep an eye out for a deal on a Fidenza (I've seen them several times in the $250 range).

I've seen a few on this site, but they all require skills and tools that most of us don't have. Lonewolf is the only solutions I've seen available for purchase and they're not cheap, although they are beautifully done. http://www.lonewolfperformance.com/nissan.htm Get's me started on "bang for the buck" thinking and LS1s ... But we digress from the OP's question - SEARCH is your friend.

You should be able to come pretty close to your HP and TQ goals with either carbs or FI and once set up, both can be reliable. I'd recommend you spend some time searching as this has been discussed countless times and there are plenty of threads where people have documented their builds and the issues they had to overcome.

A few things: - You have the cranking RPM set too low. Raise it to 350 rpm. - You have Priming Pulsewidth set at 2.0 for all temperatures. It should rise as the temp goes down. Here's a screen shot of what I use - I set it once and since I don't have any issues with starting I haven't tweaked it further, but it's a starting point for you. - It appears that you're not using PWM Current Limiting for the injectors, so set the PWM Time Threshold (ms) to 25.4 - Required Fuel is way off at 20.0 ms with 440cc injectors. As a point of reference, I'm using stock turbo injectors (270cc) and Required fuel of 5.5 ms for 2 squirts (equivalent to 11.0 with one squirt). This gives me VE values in the idle range in the upper 20s. Calculate the required fuel, set it, and only come back and change it if the VE values are too large (>255) or too small (<5) at the extremes of the VE table. You should not be using it to tune idle. - I'm using an MSD box so my More Ignition Options are different than yours, but I wonder if Maximum Dwell Duration of 3.5 ms is ok. Perhaps someone who has MS driving the coil can comment?