bigblock96

Can both of you send me a couple good pics of them please. To big_block_96@yahoo.com thanks

For my 75 280z in good shape please I am in Florida

Jhm yes that's it cool thanks yes it had ac but is in bad shape so I am removing it so thanks

AT&T sent you a pm thanks

Only have iPhone and can't add pic

Help me out if you know what this is two little round things with hose and two wires attached to passenger strut tower under the hood

that would suck,the only other reason I can see is that the rack may have been used in other applications which might of had a adjusting collar on it maybe?

thanks guys thats what I was thinking but I was trying to get things together before I get back to the car as I am aways from where the car is,sorry Jon!

wow you guys thanks that is for a 77 280 thanks again

please is it 12mm or 14mm or what sorry

and best after going down to bare metal spray staying with the same company of products to keep from lifting cracking and such -just my .02

:rockon:sweet must have seen Tokyo drift

true X will sound a little bit off as a H will give you that deeper tone but as for performance it's so so.and don't we all wish we had a dyno in the garage too!!

hahaha and more- The Evolution of the X-Pipe To understand the importance of the X-pipe in relation to improved performance and power, you have to know about its roots. The X-pipe is really the offspring of the H-pipe design, which was first conceived in the 1960s by the major American car manufacturing companies at the time. Duel exhaust pipes for V-8-powered vehicles are very noisy, as there is no sound wave cancellation between the 2 separate four-cylinder engines and unconnected exhaust systems. Engineers were looking for a way to cut down on interior noise levels and improve the engine's power. They realized that running a balance tube between the two branches of exhaust pipe would work to broaden the torque curve (thus improving engine performance) and dissipate sound resonance in the exhaust system. In the 1990s improved technological advancements made it possible to construct an exhaust pipe that, instead of connecting by means of a balance pipe at a severe 90-degree angle, could unify the two branches of pipe to create a flow of exhaust in one direction. Now X-pipes are being manufactured for popular performance cars, usually off-road versions minus catalytic converters, but you can also find them in legal models fully equipped with proper emissions equipment. Performing an X-pipe mod is an option that you should consider. Why X over H? It has been proven time and again that the X-pipe design is more efficient than the H-pipe. Various tests have shown that for multiple cylinder engines the X-pipe outperforms H-pipe exhaust systems, especially as rpm increases, providing both better torque and power. Unified exhaust pipes work most efficiently with multiple cylinders because of the scavenging effect. With exhaust X-pipes the almost seamless connection between the two exhaust pipes allows sequential firing cylinders to salvage any spent exhaust gases from the combustion chamber more efficiently and creates more room in the cylinder for a fresh intake of undiluted fuel and air. When you have two exhaust pipes, as the velocity in one header tube increases, the pressure in the adjacent tube is lowered causing the exhaust to be sucked out of that cylinder. X-pipes are simply better at doing the job, especially at higher speeds. Installing Exhaust X-Pipes This is a simple mod that almost anyone can perform successfully. Most companies produce exhaust X-pipes that are simple bolt-ons that can be installed in less than an hour using the usual hand tools. If you own a vehicle that doesn't have an X-pipe available, it is possible to have a custom X-pipe assembled for you. A muffler shop can construct it by taking an X-pipe union and bending up some exhaust tubing until it fits. If you decide to make your own exhaust X-pipe from scratch, so-to-speak, remember to place the X-pipe union as close to the rear of the vehicle as you can to increase the power. A Brief How-To To install exhaust X-pipes, first begin by positioning the passenger-side header pipe in place and tightening it before moving on to the next step. Make sure it is secure. Now, fit in the actual X-pipe along with the driver's side header pipe. Remember that the long leg of the X must go toward the front driver's side of the car. Now it's time to fit the pipes of the X into position and loosely attach them to the after-cat system. You might have to adjust how the after-cat is hanging for proper tailpipe positioning and tuck up the X-pipe square. On some vehicles the tranny crossmember has an exhaust hangar - if this is the case you can tack the hardware onto the pipes. Tighten the bolts and tack-weld the junctions at the X. Check everything one more time before removing the X-pipe and welding the full length of the junctions. The assembled unit now needs to be bolted back into position - simple as that. All in all, with exhaust X-pipes torque and power will increase resulting in fast acceleration, improved fuel economy and a nice quiet ride. The difference is noticeable with the installation of X-pipes on a V-8 engine - interior noise is reduced considerably because you don't hear the firing impulses of 2 four-cylinder engines, but instead hear the noise of all 8 cylinders blasting out of both pipes at once.

http://tinyurl.com/32m9mb this gives a lil about header design. a lil more-from SCM To get the best breathing and to help pull as much fresh fuel/air mixture into the cylinder as possible during the overlap period, it is best if a low-level vacuum or rarefaction can be created and maintained past the initial low-pressure wave in the primary pipe. A well-designed header can use acoustic energy to maintain low pressure near the exhaust valve during the overlap period. Four-into-one headers typically work best over a relatively narrow powerband. Like anything, there are exceptions, and this particular AEBS header had excellent low-rpm performance as well. The way a header is tuned is much like how an organ pipe is tuned. The optimal length used is the one needed for the primary pipe to have a fundamental note corresponding to the time when the exhaust valve opens. When the exhaust valve opens, a high-pressure pulse of hot, expanding exhaust gas travels down the exhaust port at approximately 300 feet per second. This wave of hot, moving, high pressure gas has mass and inertia of its own which pulls a suction or a low pressure rarefaction behind the pulse. Depending on the engine, the pulse can have a positive pressure of anywhere from 5 to 15 psi with the low pressure rarefaction behind the pulse being anywhere from 1 to 5 psi of negative pressure. As this low-pressure rarefaction is several milliseconds behind the initial high pressure pulse, it can be exploited to help suck residual exhaust gases out of the cylinder toward the end of the exhaust stroke as the piston approaches TDC. The build up of this negative pressure and its timing in the exhaust stroke is closely associated with the primary pipe's length and diameter, just like an organ or other musical instrument. A standard, low-cost collector like this one can still be effective, but ultimately does not flow as well as a true merge collector. This type of collector can be extremely restrictive if carelessly designed and constructed. As the exhaust valve starts to close and the intake valve starts to open, the engine enters the overlap period. During the overlap period the piston is starting to slow down as it approaches TDC and gets ready to reverse directions. To maintain good scavenging, a negative pressure must be maintained near the exhaust valve to help continue to suck stale exhaust gas out of the cylinder to make room for fresh fuel and air. As the main column of high pressure gas is almost out of the end of the header's primary tube, the pressure near the exhaust valve starts to rise again. All is not lost, however. As the pulse of high-pressure, high-energy gas leaves the end of the primary tube and is diffused in the larger diameter header collector, a reflected pulse of sound energy just like a musical note is generated, much like that of a organ. This reflected sonic pulse travels down the exhaust pipe at the speed of sound, which is usually around 1100 to 1900 feet per second in thin, hot exhaust gas, causing a slight rise in pressure at the valve. The wave is then reflected back toward the open end of the primary pipe. Just like the initial exhaust pulse, the reflected sound pulse has an area of rarefaction, or low pressure, behind it. If the pipe is of proper length and diameter, this reflected wave can be exploited to lengthen the amount of time the condition of low pressure exists around the exhaust valve. These phenomena are harnessed by the smart header designer to tune the pipe to help get the maximum amount of burnt gas out and to help pull the most fresh fuel in. Of course, because a header is tuned like a musical instrument, a header can only be optimized to produce the greatest scavenge-improving vacuum in a band of several hundred rpm. Without going into a lot of math, there are some general guidelines you can use for selecting a header. Shorter primary runners and/or larger-diameter primary runners are better for top-end power. This has to do with the tuning of the pipe's fundamental note for reflected wave tuning and the travel time of the main initial exhaust gas pulse. Just like a piccolo is a higher-pitched instrument than a clarinet, a shorter, fatter primary pipe is better for higher rpm. Conversely, a longer and/or smaller diameter primary tube is better for lower rpm for the same reasons as above. Camshaft design and the duration of the exhaust cam are a large factor in header design. Generally, the later the closing point of the exhaust valve, the shorter the header primary pipes must be. The way the primary pipes gather together is important also. This area of convergence, called the collector, is critical for proper header function. It must be of larger diameter than the primary tubes because it must be large enough to acoustically represent the end of the pipe (this is necessary to get the reflected sound wave to help scavenge the exhaust), and it must be big enough to support the flow from all the cylinders without creating excessive backpressure. Usually the collector is just a junction where all of the pipes are stuffed and welded into a larger pipe that may or may not neck down into the final size of the exhaust pipe. A well-designed collector, pairs cylinders opposite in the firing order with each other so an exiting pulse from one cylinder will not hamper the evacuation of the next cylinder. Adjacent cylinders in the firing order are kept separate so the exiting pulse of one cylinder cannot contaminate the next cylinder that may be on the overlap part of the power stroke. In a typical inline four cylinder, that would mean paring cylinders 1 and 4 and 2 and 3. The best collectors are called merged collectors. This is a collector where the two opposite cylinders are paired together in a smooth taper before being introduced to the flows of the other cylinders. Merged collectors usually produce a wider powerband