cygnusx1

If I never saw and loved the S30 original shape, then OK. But looking at it now, it just looks strange.

I always considered Saturns to be a derivative of this..

Yeah it was fun, one of the Porsche guys asked about the car because it was outrunning him on the straight. I waved most of them by because it was my first time in the solo run group and I didn't want to get in the way. I figures I could try to catch them or at least keep them in sight to learn their lines. Yeah Joe caught me with the LS1 Z, but he didn't pass me, so we could let some Porsches by. Then the motor popped and he went by me as I pulled over for pit lane. Clive, I didn't see you all day! On a 1.5 mile track we must have been equally slow! Motor is coming out and full rebuild will occur. Nothing fancy, just a clean stock rebuild, maybe a hotter turbo cam or a 280Z cam, turn the boost back to 16psi, and FINALLY get a real dyno tune. I should also say that if you are using my tune, rest assured that it has survived and evolved fairly heavy street use for about 3 years. 30 minute track sessions do not compare to street use. The engine is used in a MUCH different way.

Are you running 18psi? It could have been sloshing fuel that caused a lean out, who knows.

The NYZCC went out to run with the Porsche Club at Lime Rock Park today. I was pushing 18psi and running a tune that was somewhat un-tested over 6000rpms. Well, playing with the P cars, I had to reach into the 6k's a few times and eventually she popped. Flooded a cylinder or two with coolant. I got right off the track and rolled it to the paddock. Trailered it home. Time for a fixer upper. It was running so fast, handling great, all it needed was a fast driver....and a proper dyno tune. Ah well, what do you expect from a 160k+ mile junkyard motor running 18psi with a shady tune at the top.

You need to practice using the Vernier. You measurements are off, most likely due to your technique. I don't have the time to explain right now but I will try to find a tutorial and post it later. Meanwhile practice measuring stuff, at least until you can get consistent numbers from the same part.

I need to do the same thing. Mine are intermittent in the 280Z, and with the EDIS-6 ignition, the tachometer bounces in time with the blinkers!

+1 on the R134 conversion. I put in a new dryer bottle, and changed all the o-rings in the unions to compatible ones. I also drained as much oil from the system as i could. Then I squirted in the R134a compatible oil, and pumped the R134a in after doing a system integrity test. It has been working for 10 years with light use here in NY. Not sure if this helps but here...

I don't doubt that Bruce knows how to use calipers, but when you read the OP, you get some doubts about their proper use, and some questions about the context in which they were used. No? They were probably used wrong here, so we try to point him in the right direction. I guess he left. Maybe that was the right direction. I think I am going to UN-subscribe to this post myself. I speak from experience, my experience. Here are others. Bear in mind the OP is using a pair of $10 calipers for his first time and wondering why the numbers are off. http://mikes-models.com/blog/index.php/2008/09/how-acurate-is-acurate-digital-calipers-versus-old-micrometers/ http://www.homemodelenginemachinist.com/index.php?topic=4430.10;wap2 http://forums.pelicanparts.com/porsche-911-technical-forum/33917-micrometer-vs-caliper.html http://www.practicalmachinist.com/vb/general-archive/micrometers-vs-dial-calipers-92101/index2.html enough.

Haha, I just came back to this thread to ask if your float floats...and you already figured it out. Good catch.

Most of the error, when measuring ID with calipers comes from the user. It's a bit tricky to get the caliper directly across the diameter. Any skewing and the reading comes in short or long. When measuring OD, you have much less room for user error. That's also the advantage of using bore gauges or expanders. I agree, for a quick estimate to 2 decimal places, with a competent user, they work fine. You are rolling the dice when you go for that third decimal. The fourth decimal, using the ID side, is a bit of a joke, when doing true precision work. Measure it three or four times and see what you get.

But when you measure the expanders with a caliper, you are using the same side of the caliper that you used to measure the piston. The "ID" side of cheap calipers is highly suspect.

Is the needle valve shutting off when the floats push it up? Stuck needle valve is common. Also check your fuel pressure.

Here is a video that might help explain caster. It doesn't get into toe, camber, and ackerman, and how they are effected by caster, but maybe it will help to illustrate caster. http://www.ehow.co.uk/video_2327628_caster-car-steering-system_.html

Really cool. Love it.

It is difficult to get an accurate measurement of a bore directly, with a basic $10 caliper. Yes, it can work but it's not the proper tool for measuring bores accurately. Especially if it was purchased cheap, and probably not properly calibrated or built to any tight standards. The ID and OD sides of the tool might not even jive with each other, I am willing to bet. Digital does not equate to precise. He should not go spewing the numbers he is reading to a machine shop, based on what he has measured with his calipers. Or should we tell him to just go with those numbers, they're fine. bore measuring tools http://www.google.co...i=g-m1&aql=&oq= At a minimum, use these: http://rover.ebay.co..._categ_id=12576

I suppose that the S30 engineers kept caster angle shallow to keep steering effort down?

Some people call pistons, cylinders. Might have something to do with the cylindrical shape? Get over it. His calipers are out of whack, and he shouldn't be using them for what he's doing anyhow. My engine has 6 cylinders, or does it have six bores...or does it really matter.

Yes, and no.

Haha, never thought about that before. Follow the women, I always say! My neighbor just got a Z32, Red TT, manual, with 62k miles on it for $8k. It has a few problems, most of which were listed above. The car is gorgeous, stock, and drives like a dream. After a few little fixes, it's going to be an awesome car.

Not yours anymore but the emotion is still there.

Run NGK's and get the factory spec plug that matches the motor in your car. There is probably a chart at the NGK website that gives you the differences between each model plug.

Bores need to be measured with a micrometer and/or expansion gauges, while using proper technique. Most calipers cant do a good job of measuring ID. There can also be discrepancies between the ID and OD calibration of the caliper. Definitely need to be validated, and use a micrometer for critical measurements. Also check for roundness of the bores and pistons. http://www.youtube.com/watch?v=jFeCpDbOpjQ

So I finished the install and did a rough alignment with some strings from the rear wheels to the front wheels, and a tape measure. I drove it, and it still felt muddy but the ratio was definitely better. Obviously, I hadn't really improved the situation much. So I read up on Ackerman and Z alignments again. I decided my tires might just have soft walls, and could be the cause of the muddy feeling. An easy test was to bring them up to 40psi and test drive. This helped a little but not as much as I thought it should. So I decided to take out the 1/8" of toe-in I had. With zero toe and 40psi it was much closer to what I wanted. I decided to go even further. Since I have about -1.5 deg of camber, I thought I could get away with some additional toe-out without getting too "wander-ish" up front. I had gotten the steering wheel on dead center, with the rack on dead center, with zero toe. All I did now was turn the tie rods out equal amounts on each side to get about 1/8" of toe out, and that really woke up the car. Now the steering is much lighter on turn entry, and holds it's course with a linear feel to the steering wheel. Course corrections are quick and easy in mid corner. I may try a tad bit more toe out just to explore the ranges. In conclusion, the 240Z rack does feel really good in the 280Z once you get the front end dialed in. I don't think the improvement is worth spending the money on a new rack, but since my red 240Z came with a spare one, it was worth throwing into the 280Z for a nice quick steering mod. If you haven't tried toe-out in your Z...go do it! It's still not as snappy as the 240Z but I think the 300-400 pounds of the 280Z makes that difference.

Let me summarize/clarify/ask some things about what I read here in this looong thread> 1)When the car leans to the side in a corner, the inside (fronts) wheel toe's-in and the outside wheel toe's-out (bump steer?) I see this when I jack up the car. 2)Negative camber causes the tires to "steer" inwards toward the cars centerline, as a result you can run more static toe out to make them go straight ahead..so to speak. 3)Parallel steer means that the wheels follow the same X radius around a curve? or do they follow each others (left and right radius) radii? 4)On a basic Z, static toe-in adds anti-Ackerman characteristics in corner, and static toe out adds pro-Ackerman. 5)Lengthening the TC rods increases caster angle and does what to the handling and Ackerman?