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Corzette

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Posts posted by Corzette

  1. Hey guys...Sorry. I didnt check the posts. I think it was a 75 or 76 Skyline. They are the exact same configuration as the Z. Its a direct bolt on. I will ask about the year as I saw another one here in Oki with them. I sold that car back before the Saudi War...Im building my new one to resemble it. By the way, any luck on getting a G-Nose anywhere? Got any contacts in Japan? The vents are off a 78 Z28...

     

    CorZette

  2. I just wanted to chime in. If you want to see what bad floor pans look like...go to my site and view the first album. I did a total replacement with Zinc metal. It was a PITA to say the least, but well worth the effort. I paid about $50 in materials and nothing in labor, but it would have cost big bucks Im sure.

     

    Corzette

  3. At anyrate, I have just decided to give these flares away because Grumpy did such a good deed for me. I feel like doing the same for someone. I have a set of front SCCA style flares to give away for free. You pay shipping. It wouldn't be much, maybe $30 or so from here (Okinawa Military Post) Look in your MSA books and they show a pair front and back. They go for $100 plus shipping for fronts and the same for rears.

     

    Corzette

  4. OK everyone heard that right..I tried to pay but Grumpy says no! Thanks Grumpy, you are one in a million for sure. I think I am now motivated to do a good deed for someone on this board as well. I have a set of front over fenders that someone was wanting that I think I will give away. Afterall they are doing me no good!

     

    Thanks Grumpy!!!

  5. Grumpy, just wanted to say thank you very much for your help. I just recieved the rear cap in tact. I will install this weekend. I should have more new pics up next week at my site. Hey do you have a PAYPAL address that I can send you some money on. I feel bad accepting this for free....

     

    CorZette

  6. Hey guys I have a question. I just bought the EAgle H Beam rods with arp wave locks I think. What kind of tool do I need to take these friggen nuts off with. This is frustrating to say the least. I didn’t know I would need special tools to install. Please can some one advise… Grumpy you out there?

     

    If it isn't one thing its another...I thought full floater meant no worries...it would be nice if I could get the FRIGGEN NUTS OFF to install them... :confused:

  7. Grumpy sorry for the late reply...no I haven't got it yet but I am sure it will come soon..usually takes about two weeks. I can't wait..Im going crazy. I still need heads, rockers, rollers, push rods and intake. Well Ill get the heads next month. Since my monthly allowance is $800, I should be able to speed things up after getting the heads. I am still undecided on those damn headers. I am leaning towards the hooker full length because they have a part number for them and they sound better than the sandersons as far as fit and price. Will putting those block huggers on really take away power from me?

     

    TB

  8. The first thing to consider is the size of the primary tubes. Bigger tubes will give better breathing for top-end power, but the low velocity at lower rpm will make for more reversion to contaminate the next charge, so larger tubes will usually cost some low-end power. It is a common mistake to port the heads to match the headers primary pipes, but this does more harm than good. The primary tubes should be larger than the exhaust ports, this makes a reversion dam to limit reverse flow. This is most important on the port floor where velocity is the lowest. If your looking to enhance power in the 1500-3500 rpm range, you'll want 1 1/2"- 1 5/8" primaries on a small-block and 1 3/4"-1 7/8" on bigger cubic inch big blocks. Big tube race headers can help power above 5500 rpm, but may cost some low-end power. If you don't intend to rev the motor much past 5500 rpm, go with a smaller tube header. On a small block Chevy, going bigger than 1 3/4" will require an adapter plate that will need to be ported to the head and you must use a header with a special bolt pattern to bolt up to it.

     

    Primary Tube Length

     

    The shorter the primary tubes are the higher in the rpm range they will help power. Each exhaust pulse causes a high pressure wave to travel toward the collector. When it reaches the collector it is inverted and travels back toward the cylinder as a low pressure wave. It is this low pressure area that helps scavenge exhaust out of the cylinder during the overlap period. This happens when the low pressure area reaches the exhaust valve during the overlap period. The low pressure area helps draw out the exhaust and draw in more fresh intake charge. All the pressure waves travel at the speed of sound (1200-1300 ft/sec in the hot exhaust). With all the pressure waves traveling at a constant speed, you can see that the header can be only be tuned to a narrow rpm range. On a street car that needs low-end, the tubes should be longer, in a high rpm drag car they will need to be much shorter. To get you close to the optimum primary tube length, use this formula:

     

    Length (in inches) = (CID x 1900) ÷ (rpm x pri.OD2)

     

    Equal Length Primaries

     

    Equal length headers can be an advantage on a street car with a full exhaust system, but even more so an open header engine race engine. Whether they are worth it on a street car really depends on price, they are usually much more expensive. That money may get more bang for the buck elsewhere in the engine. As long as the primaries differ no more than 2 inches, they will be fine for a full exhaust system street car. Equal length headers will work the best when the banks of an engine are even firing (and most V8's are not), 180° crankshafts even out the cylinder firing and work the best with equal length headers, but the costs and the fact that they cannot be perfectly balanced makes them impractical for the street.

     

    H-Pipes

     

    Adding an simple connection between the pipes can boost power in a certain rpm range. Most header primaries are tuned to operate on the second set of pressure waves, to tune the crossover to the same rpm range it will need to operate off the 1st set of waves. If your primary tube ends 30 inches. From the back of the valve and is using the second set of pressure waves, putting the crossover 60 inches from the valves will help power at the same rpm range using the 1st set of pressure waves. In order to be effective, the crossover should be at least 90% of the diameter of the pipes.

     

    X-Pipes

     

    This is a more expensive crossover, but works a little better. The X design allows the pressure to go form one pipe to another much easier by eliminating the 90° corner. The gasses have smooth bend to follow. X-pipes take up much more room which makes it harder to place them in the best location when ground clearance is a problem. When figuring the placement of the X pipe, measure the point where the pipes meet.

     

    Thermal Coatings

     

    The biggest performance benefit of coated headers is that they help keep the heat in the exhaust system. As the exhaust gases cool, they also lose velocity. By keeping the exhaust hot, the velocity will be higher and you will get more of a scavenging effect. At low rpm, reverse flow will be reduced also. By keeping the heat in the exhaust system, you also reduce under hood temperatures, which can really be a plus if your carb is breathing under hood air. Thermal coatings (like Jot Hot) also look nice and resist rust to help the headers live longer.

     

    Thermal Wraps

     

    Thermal wrap does a better job at insulating heat and reducing under hood temperatures, but they also tend to hold in moisture and cause rust. If you use wrap on a street car, you should use a coated header to help it last. Headers will not last as long if they are run hotter, and wraps make the header run much hotter. The metal will fatigue much quicker. Gaskets will also fail sooner if the system is hotter, especially the collector gaskets.

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