johnc

Not yet.

I wrote this up a while ago and it was a sticky, but now it seems to have vanished:

The one way check valve is to keep fuel from spilling out of the vent line if the car rolls over. Geenrally you want to allow air into the tank and not let anything out. There are different kinds of check valves with the more expensive ones allowing air and small amounts of fuel to flow both ways but seal up tight when the car is inverted. That's not really an issue. Once the fuel pump starts running or you crack the filler cap the pressure is released. I've never had a problem with it at the track. Park outside or run a tight check valve. You can run to a charcoal cannister but after time it will be saturated and become a fuel saturated bomb. What you're dealing with kinda comes with the territory when you start adding racing parts to a street car. Fuel cells are designed to work best when they vent straight to atmosphere. They don't have the vapor trapping requirements that DOT legal fuel systems do. Sounds like the fuel cell isn't vented properly. Makes me kinda wonder about the rest of the fuel cell installation.

The PC680 comes with two options: A metal case and/or SAE sized terminals. If anyone's interested I sell the basic PC680 for $95.65, the metal jacketted one for $106.65, and the SAE terminals are a $7.32 add-on to the above prices. I also make an aluminum bracket to mount the PC680 upright. I've sold and installed a few of these in 240Zs. http://www.betamotorsports.com/products/OdysseyBatteries.html Unfortunately I can't match the $75 prices you sometimes see on eBay. I pay about $10.00 more then that for my cost. I guess if I started selling hundreds...

Run it to to right rear corner under the car and make sure the end of the vent line points down and is in the air stream. Also, you do have a one way valve in the vent line and you've built a complete, air tight metal cover over the fuel cell and lines separating them from the passenger compartment, right?

Hear it now: tires of that size increase the 240Zs tendency to tramline (follow road imperfections). Replace them, they are bad if cracked. Which part of the tire is pointing in? The top, the fronts? What is too much? 1 to 1.5 degrees negative on a street car is actually a good thing and won't noticeably increase tramlining IF THE REST OF THE SUSPESNION IS UP TO SPEC. No. Offset lower control arm bushings are another option. I think your issue is a worn front suspension and wide tires. I suggest you replace tie rod ends, steering rack bushings, TC rod bushings, LCA bushings, and ball joints then get the car correctly aligned.

If the car never or rarely sees an autocross or a track then yes, I do think adjustable LCAs, camber plates, and coil over kits are overkill. A perfect example is John Williams. He had a 240Z that was 90% an autocross only car and he didn't have camber plates, coil overs, or adjustable LCAs, yet he was very fast in BSP locally. Plus the car was reasonably comfortable and quiet on the street when he was driving it to and from events. You can make a 240Z handle very well on the street without resorting to all the adjustable components. Now, I'm not trying to discourage anyone (remember, this is HybridZ!), I just feel that for a street driven 240Z your handling money is better spent making sure the chassis and suspension is in perfect condition then dropping thousands on coil overs, camber plates, and adjustable LCAs. I know this sounds funny coming from me (I didn't bat an eye spending $8,000 on Penske shocks for my 240Z) but I'm pretty conservative when it comes to street modifications.

Thanks for serving! Glad you made it back OK.

I was really surprised by the price Don is charging for the camber plates ($185 per pair) so I made a couple phone calls. Here's the differences between his plates and the EMI Racing camber plates (at $300 per pair): EMI uses Mil-Spec monoball bearings. EMI uses all stainless mounting hardware and spacers. EMI camber plates are manufactured from 7075 alloy aluminum. EMI camber plates use roll tapped threads (cut threads strip easier). EMI camber plates integrate the upper spring perch with the camber plate. EMI camber plates use Torrington bearings to eliminate spring wind-up. Is all this extra worth the additional $115 per pair? Its up to you to decide. BTW... IMHO camber plates are overkill for a street car and the problems mentioned at the start of this thread have more to do with the wider tires then camber.

Wow! EDIT: Ooops! I guess my Wow confused people. I was Wowing the $185 per pair price of the DP camber plates...

And that's a common misconception. The air in the plenum and in the ITBs is never at a dead stop, there's always velocity in any intake. Proper runner design can keep the velocity up even at part throttle. Again, its MOI, not the fuel or intake system that mostly determines throttle response. The limiting factor on throttle response when the throttle is snapped open is not accelerating the air mass in the intake (and the exhaust, don't forget that part). The limiting factor is accelerating the valvetrain, pistons, rods, crank, flywheel, pressure plate, clutch, transmission, driveshaft, differential, halfshafts, stub axles, wheels, tires, sprung, and unsprung weight. As Keith said above, a race track is very different from blipping the throttle in neutral.

Sunbelt built it custom. I can make one and I do have the dimensions/specs. Probably be about $1,500 for the manifold itself. Here's a picture of it on the L6: FYI... throttle response has more to do with MOI then fuel delivery.

Careful about broad generalizations like that. My race car did just fine with a tuned plenum and a single 65mm TB. 320hp and at least 200 ft. lbs. of torque from 4,000 to 7,200 rpm (Max of 275 ft. lbs at 5,600). My engine budget was basically unlimited and the engine builder chose a singe TB over individual TBs.

I'm sure it can be done. I'm not sure the effort will be any better then a custom intake manifold with tapered runners, a properly sized plenum, and a single throttle body. Both will probably cost about the same.

In general, when building a track car (and a street car for that matter) you focus on these main items in order: 1. Safety 2. Reliability (can't race if it doesn't run) 3. Repeatability (engine has good driveability, suspension, brakes, and steering are good so the car turns and stops the saem way every time) 4. Speed (the last thing to work on) Safety Items 1. Good FIA approved race seat for both driver and passenger. Must be properly and securely mounted. 2. Approved 5 or 6 point racing harness for both driver and passenger. Must be properly mounted. 3. Snell 2000 or 2005 full face helmet. 4. SFI rated driving gloves. 5. 5lb metal fire extinguisher securely mounted and within easy reach of the driver while the driver is belted in. 6. SFI rated racing suit and Nomex underwear. If you don't want to wear the suit, wear a cotton long sleave shirt and cotton long pants. Maybe buy the Nomex underwear and wear it under your regular clothes. 7. SCCA approved roll bar or roll cage. 8. Window net. 9. Kill switch both inside and outside the car.

You are getting somewhere with the car! You're finding problems and fixing them.

You've got all you need already on the car. As many have said, track time, track, time, track time. Any additional money spent on your car (other then for safety and reliability) is not going to make you any faster. Sorry to be an additional bearer of bad news, but your car is slow because you are driving it Luckily, that's something that can be fixed and once its fixed, you'll be able to drive ANY car much faster. Good luck and remember, you're doing this because its fun!

Maybe the test results you're reading are more indicative of the shoddy testing practices of various magazines? The vast majority of tests done by magazines are sponsored by the product manufacturers themselves. Unless things really go wrong (as in the Magnacharger test) the sponsoring manufacturer is going to come out of the test looking pretty good.

The first hood is getting laid up today. Hopefully its in my hands by Wednesday next week.

Think about it, you've got an intake tract that has some level of vacum and an exhaust tract that is slightly pressurized. You open a connection between the two and what do you think is going to happen?

Not a good idea.

OK, since I don't own a Z at the moment that would help me out. I'll even build you the little front brackets for the hood pins.

Most camber plates DO put spring loads into the monoball which can be a bad thing. The EMI Plates put the spring loads from the upper spring perch into the camber plate itself. The front plates have a Torington bearing between the spring perch and the plate while the rears just have direct contact. The upper spring perches slide onto the bottom of the camber plate and are held in place by a c-clip.

Not very. Most of the time the anti-roll bars will act as droop limiters.

And I think that's where some confusion comes in when reading Race Car Vehicle Dynamics and some of Carroll Smith's books. All of those experts are used to working with "real" race cars like Formula Fords. Many of the suspension topics ARE about Formula Ford suspensions. In those kinds of cars you don't want any roll at all and you're working with fully adjustable and optimized suspension geometry. Sometimes its very difficult to translate the expert's recomendations onto a strut equipped, cost limited, 30 year old chassis. Occaisionally its down right impossible without rebuilding the chassis into something that looks like a mutant Lola/Van Dieman/VW Bug.