Zmanco

I added fittings to 5 and 6 this weekend. I decided not to do 4 because it's not clear from this discussion if the trade off of better cooling on 4 has any negative effect on reducing cooling on 5 and 6 which seem to need it more. Also, I noticed that the intake manifold has webbing where 4 would need to be drilled. Did others just remove the little plate and drill a large enough hole to fit the nipple, or is there some other approach that I'm missing? This webbing exists on both the ZX and turbo intakes, not sure on the earlier ones without EGR.

I read the thread all the way from the beginning (again) and decided to only do 5 and 6. I'm guessing that the benefit of including 4 would be offset by reducing the flow from 5 and 6. We have a track day on Sept 12 that I'm hoping to attend and that will be a good test of this mod.

FYI, I too ran with flat top pistons (ITM .030 over) and N42 head and moderate cam for 10.3 CR and had detonation issues on 91 premium (that's the best we have), even at our altitude here in Colorado. I'm running megasquirt so in the end backed off the timing in the 4k - 5k rpm range by almost 10 degrees. Boy could I feel the torque fall off as it passed through that range compared to the cool days when I could run more advance. As Jon and others said, I think running a lower CR and being able to run full advance would be a better combination. And like zeis150, I too am going turbo - power really is addictive

You've confirmed that you have either a 3.36 or 3.54 diff, your tires are pretty close to stock diameter and you have a stock 4 speed. You've measured your speed with a GPS (eliminating the speedo gear from this discussion). I think all that leaves is the tach, no? BTW, just remembered that my dwell meter can also measure rpm up to around 2k rpm IIRC. While that's probably not high enough to do a proper calibration, it would let you get a rough idea if your tach is even close to reading correctly.

Thanks for all the suggestions. I used the electrolysis method to remove the surface rust and then some 0000 wool with WD40 and they cleaned up well. I wish something would go as-planned on this project ...

I'm in the middle of building up my first turbo motor and am planning on adding the nipples to the back cylinders. My question is if I should do just 5 and 6, or 4, 5, and 6? With the head off it's not big deal to do 4 as well, but I figure that will add more flow into the return line (I plan to connect to an unused nipple on the thermostat housing) and could reduce flow to 5 and 6 which seem to need it most. My goal is to have a reliable 275 - 300 whp engine that I can run on the track (road course with 20 minute sessions) hence cooling is going to be key for longevity.

I hear you, but here's the real issue: there is no other source for .160" lash pads, plus I've been waiting for these for almost 4 weeks and am behind on the build. So I'd really prefer to find a way to use them if it can be done reliably. What do you think about soaking with WD40 and then using some really fine steel wool? It looks to be surface rust only.

Believe it or not they came from Nissan Motorsports (via a dealer). I don't think there is any other source for lash pads.

My new lash pads finally came in and there's a lot of surface rust. I really only care about the "channel" where the rocker will slide and am wondering if it's ok to just install as they are? If it was a bolt I'd use the wire wheel to clean it off, but for a machined surface that doesn't seem like a good idea. Suggestions?

If you can find another tach that's known to be accurate, you could do a temporary install and compare the two. I would suggest comparing the two at cruising revs, maybe 3k and 4k rpm. At idle I doubt the error will be large enough to be accurately measured and adjusted. FYI, mine read about 300 rpm high at 3k rpm meaning it was ~10% off. At 900 rpm that's only 90 rpm error which I don't think you'll be able to measure. There is a potentiometer that is adjusted with a small screwdriver through a hole in the back of the tach. Hint: only do this with the ignition off. Otherwise you will damage the tach. Ask me how I know.

Are you sure the tach is accurate? The early 240Z tachs can easily be off a few hundred rpm. They are adjustable. Still, it's not too hard to jack up the rear and count how many times the drive shaft turns for each turn of a wheel. That would get you pretty close on the diff ratio in short order.

The stock 240z tachs are current triggered - 260 and later are voltage triggered. This means that you need a "tach adapter" in order to get the early tach to trigger from an ECU. MSD sells one for about $50. But just an FYI, they're not very durable and somewhat temperature sensitive. Don't mount it in the engine bay or anywhere else that gets warm. Alternatively, you can just wire it to trigger off the coil as the factory did. It's been a while since I looked at the factory wiring diagram, but I'm pretty sure that the tach is wired in series with the coil. Perhaps someone else who's done this more recently can chime in?

Just a quick reminder that the last day to register and take advantage of the special hotel rate of $88 at the Radisson is August 27. More info on the hotel can be found at http://www.zccc.org/radhotel.htm.

Thanks aarang, it seemed too easy. I'll go with the traditional Al tubing and Si hoses.

I got the idea to use this ducting from McMaster from Matt Cramer's blog. http://www.mcmaster.com/#5499k244/=38oy3y What do you think of it? The temp and max pressure seem fine for my application (target 15 psi boost or so). The only thing is the ability to withstand vacuum. It seems that there could be conditions (perhaps transitioning from a high rpm downshift with the throttle closed and then suddenly opening it) where there might be significant vacuum in front of the throttle plate. Should I be concerned about this? I was planning on 2 1/4" if I went with typical Al pipe and silicon hoses, so was thinking of going a size up with this since it's not as smooth inside. Does that make sense, or should I just stay with 2 1/4"?

I spoke with APT Turbo to get an RMA and he asked me if I was seeing boost creep. Since the car isn't on the road I said I don't know yet. We talked about their 3" V-band solution: http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=ATP-WGT-023&Category_Code=WGT1 which I had been leaning towards anyway as I think I'll eventually go with a 3" exhaust. http://forums.hybridz.org/showthread.php?t=148513 Long story short, I ordered it along with a 3"-2.5" adapter to go between the v-band flange and my existing 2.5" downpipe. I'm getting to that point in this project where I need to get it done and I'm beginning to throw money at it. Not my preferred method, but the summer is going to be gone soon...

So the wastegate arrived and these guys must be brain-dead. I called to ask what the ID of the flange was and after waiting a few minutes, the guy came back and said 2.5". I asked if a 2.5" exhaust pipe would fit inside and the answer was again yes. So I ordered it. Turns out it's closer to 2.1". How is it possible to so misread a ruler? So now I'm looking at this one: http://cgi.ebay.com/ebaymotors/t3-t3-t4-5bolt-downpipe-flange-to-2-5-v-band-adaptor_W0QQcmdZViewItemQQ_trksidZp4634Q2ec0Q2em14Q2el1262QQhashZitem2ea70a6691QQitemZ200370972305QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories But I'm new to V-Bands so I have a noobie question: is the ID of a 2.5" V-band flange actually 2.5"? In other words, will a 2.5" exhaust pipe fit into the flange? I don't want to go through this again.

Yasin, you have a difficult but fun choice to make: bring the white ZX with monster motor, or the pristine stock Roadster. Either one would be a huge hit at the show! Nice to have choices Ryan, that doesn't sound good. I'm in the middle of the turbo-ectomy, but have enough travel outside CO in the next few weeks that getting it on the road and safely tuned is going to be a push. Still, hope you can come by one of the events, perhaps the Shine n Show on Friday?

Planning is well on its way for the MZF 2009. People will be arriving on Thursday September 10th at the hotel for a Meet and Greet. Friday we'll have a Shine n Show at Tynan's Nissan and an open dinner (plenty of fun places to go downtown Denver). Saturday will have 2 options: spend a day on the new High Plains Raceway track, or take a drive down to Garden of the Gods. At the end of the day we'll have a banquet with auctions and awards. For those staying over on Sunday, we'll have a mountain drive up into Idaho Springs. All together it will be nearly 4 days to enjoy your Z and meet and get to know other fellow Z owners in beautiful Colorado. And keep in mind that if you have an Infinit G35/37 or even early Roadsters, you're invited too. I do have to bring up a little reality check given these tough economic times: Events like these are notorious for people signing up at the last minute. The problem for the club hosting it is that financial commitments for things such as rooms and banquets have to be made much farther in advance. Usually it's safe to "build it and they will come" but with the economy remaining weak, this is probably not the year to take those kinds of risks. What this all means is that if you are planning on coming, please sign up in the next 2 weeks to ensure that we'll be able to make the event happen. Visit the website at www.midwestzfest.com to learn more. You can register online, or print out the form and mail it if you prefer. We at the Z Car Club of Colorado hope you can join us!

Thanks for the suggestion, and I think it would. However I just ordered a new unit from ATP Turbo this morning. http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=ATP-WGT-026&Category_Code=WGT1 I'll grind off the weld for the MSA 4 bolt bracket and replace it with this one instead. Not exactly "bolt-in", but like with most other upgrades, it rarely is.

I have the 240sx rear calipers with 300zx rotors in the rear. Once I had the rears properly balanced with the fronts I was pleasantly surprised how much of a difference it made. On the track I was able to brake noticeably later than I had before without front lockup. But on the street where it's rare to threshold brake, I don't think it would matter as much.

The outlet for the turbine is 2.25", but it's a stage III wheel. Can I just use the wastegate cover? I don't want to change the housing or turbine at this time.

I ordered my Garrett T3/T4OE with the 5 bolt exhaust side thinking I'd be able to swap the internal wastegate from my existing stock turbo. But while they're close, they clearly are not interchangeable. I already have the MSA down pipe with 4 bolt flange. I've found a few sources online for just the T3 wastegate, but they are either V-band or 3 bolt. I did find a 4 bolt, but the holes for the studs are not evenly spaced as they are on the MSA down pipe. So I'm looking for suggestions. Anyone know of a source for the wastegate that will fit the factory 4 bolt exhaust flange? Or perhaps has someone converted to an external wastegate for a T3 and not need their old internal one anymore?

Bump. Anyone?

For your intended use (street and autocross) as others have said, I would NOT recommend the Toyota 4x4 upgrade as it will give you too much front brake bias. You will find that even with the prop valve all the way open that your fronts will lock first. The rears will not be doing their fair share of braking. I solved it by going to a rear pad with a higher coefficient of friction, but it's expensive and time consuming to work it out trial and error. If you do the upgrade anyway, I would suggest you go with the vented calipers that have the same size pistons. That way you can buy pads for the early 300zx which gives a better choice of performance pad materials. The truck obviously doesn't have the same variety of choices. Note: you do have to cut off a tab on the backing plate, but it's trivial with a dremel and cutoff wheel.