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johnc

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Everything posted by johnc

  1. Tim, If you don't mind rebuilding one, I'm probably going to sell the N42/N42 long block that was in my BSP 240Z. Static compression test after we rented a track to test the Penske's came back 185/120/185/180/120/165 so I pulled the motor planning to rebuild it. There's .010 room left for a rebore (if needed) but I was hoping that honing would fix the problem - otherwise its time for new pistons. The head needs refreshing too - 25,000 autocross and track miles kinda wears things out. The head and block have all the trick stuff from JG Engine Dynamics for IT/BSP and the engine had 9.6 to 1 compression even with dished pistons. Johnson Machine in Monrovia did all the work on it for Javier back in 1996 and they still know what they are doing. Figure about $500 for block machine work and $150 for pistons if you need them. The head would be about $400 also assuming the rockers and cam are still good - they still look fine. I was going to ask $1,200 without the rebuild and $2,500 to $3,500 with depending on what else I throw in (header, exhaust, SUs, intake, ignition, etc.). Just an option if you decided on a L28...
  2. Sigmund Freud? I second the Sunbelt recommendation. BTW... don't post a message with all capital letters. Its bad manners.
  3. The fat lady be signing! Giants are on the bus home lookin' for someone to replace Dusty and his Romper Room dugout! Whooooo Hooooo!
  4. There are hoods that look like carbon fiber and then there are real carbon fiber hoods. Hiten Patel (little.simba@cox.net) has been making real carbon fiber hoods, doors, and rear hatches for a few EP 240Zs. The hoods weight under 5 lbs including attachment hardware. They also cost about $1,000. If you want the street racer look then you can get something around $500 or less, but it ain't real.
  5. Made 10 and recieved 6 phone calls last night to friends in the Bay Area making up for simlar calls a few days ago. If these guys win it I might be a season ticket holder again.
  6. Its really tough for a man who's provided for his family 40+ years to suddenly face the possibility that he can't anymore. Help him keep his pride - its what's holding him together right now. You've made your offer of assistance but start working on ideas and ways he can still be the provider. And be glad you've had the time to tell him you love him. That will help him more then you can possibly imagine.
  7. > So John, the important question is have you > gotten to drive yours yet?! No, and that's the dirty, nasty little secret. With being in welding school for 7 weeks and Erik going through splitter/wing hell on the Schley Viper. The Z goes in tomorrow though and I should be ready by Christmas.
  8. > Maybe we should all take up a collection and > send a P90 and an N42 to Sunbelt, have them > port them equally, and mill the P90 to where it > has equal CC's on the combustion chamber that > the N42 has. Figure about $2,000 per head plus dyno time.
  9. Sometime next year (or maybe 2004) I'll get Sunbelt to build a P90 for my NA 3.0L. Then we should have a viable comparison of a heavily modified N42 vs. a heavily modified P90. Kinda like comparing genetically altered apples and oranges. $10 says we end up with an orange the looks and tastes like an apple and an apple that looks and tastes like an orange.
  10. You can TIG or MIG weld 6061 with 4043 filler and be pretty much assured of no cracking. But the weld area will lose at least 30% of its treated strength. For example, T6 will fall back to at least T4 in the heat affected zone.
  11. > A large combustion chamber (low CR) boosted to > the same pressure as a small combustion chamber > (high CR) contains more fuel/air and hence more > power. That would be true if you were measuring cylinder pressures just before combustion. In my post earlier I was implicitly referring to max cylinder pressures after combustion (usually about 30 degrees ATDC) which, if they are equal, then you will be producing identical power (assuming identical rpms.) But, that's one of those "all things being equal" arguments that has no basis in reality.
  12. > John, while reading your post, I was wondering - > does the pressurization of the intake charge > aid in fuel/air mixing? Don't know.
  13. Pistons are also cooled by oil. Exhaust gas temps are generally 1,300+ degrees in the header primary pipes but drop considerably by the end of the collector unless the header is coated or stainless. Try thin wall 304 stainless. You can also try to find some aluminum alloy tubing (5356 or 6061). I assumed you were talking about 1100 (pure) series aluminum.
  14. Since aluminum melts at ~1,200F and noticeably softens/elongates at ~800F I would think the exhaust system would have problems staying together.
  15. Heat, heat, heat. If you can cool the intake charge and the combustion chamber down then running boost on a high cr engine is subject to the same cylinder pressure limitations as running boost on a low cr engine. Ideally you should be able to hit the same cylinder pressure numbers with either setup. Unfortunately, this cooling is done mostly with fuel so, as said above, precise fuel management and high octane fuels are key. In addition you can add oil jets to the undersides of the piston, intercoolers, piston and combustion chamber coatings, etc. I tend to look at engines as either pressuruzed or unpressurized. Some auto manufacturers have built very successful high cr pressurized engines, but none of us have those kinds of resources.
  16. Actually, the Invertec 205 can go 110 or 230 with an automatic internal switch. On 110 volts you get the following duty cycles (AC or DC): 150Amps, 40% duty cycle, 34.0 amp draw. 120Amps, 60% duty cycle, 24.5 amp draw. 100Amps, 100% duty cycle, 18.9 amp draw. At 230 volts you get the following (AC or DC): 200Amps, 40% duty cycle, 28.8 amp draw. 170Amps, 60% duty cycle, 17.8 amp draw. 140Amps, 100% duty cycle, 14.2 amp draw. And the whole unit weighs 33lbs and comes with a carrying strap. The Plasma cutter is a 230 volt machine with a 50% duty cycle at its max 55 amps and drawing 30 amps.
  17. Just bought a Lincoln Invertec V205-T TIG and a Pro-Cut 55 Plasma cutter. Already have a Miller 135 MIG. Somehow I need to convince the wife that she needs to park her Miata in the driveway from now on. BTW... if all you're using a gas torch for is cutting, then use a Propane bottle, cutting torch and tip with your Oxygen bottle. It cuts as well as Acy and is cheaper and much safer.
  18. No such thing as a 1968 Datsun Z. Regarding the swap into an early Z... I'm not an expert on the Datsun Roadsters but aren't the early Roadster 4 cylinders pushrod engines? Those engines tend to be worth more as replacements for Roadster restoration projects.
  19. C&R makes really nice ones. Figure about $1,000 for an aluminum double pass with a 4 plate heat exchanger.
  20. Sorry LJ, Jeffp and 240Z Turbo are in charge of the cam threads.
  21. They are interchangeable if you use the corresponding companion flange.
  22. FWIW... all the instructors at the Lincoln Welding School use standard lens helmets. All of them can get any Lincoln welding helmet they want for free and all prefer not to use the auto darkening ones. Their reason - too heavy and they tend to flash with extended use and heat.
  23. > 320 flywheel hp (correct me if I'm wrong here, > somebody) Dan, If this refers to my engine, its 305hp at the flywheel. If its someone else's motor, I'd like to hear more.
  24. It depends on what you're doing with the car. Although I tend to hang with the road racing crowd and that might limit my experience, the most common stub axle failure is flange separation from the axle. This is caused by fatigue failure starting from a stress riser at the fusion weld. The fatigue load is the lateral loads imposed on the flange from racing wheels and sticky track tires. If you are doing a lot of track or autocross stuff then you'll benefit from the 280Z sub axles (27 spline). I also assume that you'll benefit if you drag race frequently and do hard launches. For a street car, there's probably no benefit to the change.
  25. JE Pistons in Huntington Beach. About $900 a set with all the additional work Sunbelt did.
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