ianz

Hello All, Thanks to everyone for the great posts! I am currently doing an LT1 T56 swap into a 78 280Z. I am using the JTR kit and have a question. Did you all use the offset engine mount spacers and if so, did you go by the manual and put the thick (2" spacer) on the driver side? Clarification would be appreciated as doing this seams to move the engine over to the passenger side so far that the exhaust header will not clear

Hey Mike Never thought Nasty car would come in handy, but this is AWSOME!! I've been away for a while but Tony D gave me the heads up about this and hear I am!! If you go for the second day, count me in for a donation cheers, Ian

Again, They don't call aero a black art for nothing...... There are two concepts that address under body aero..... 1. Block as much air as you can from going under the car to minimize lift caused by the air being slowed down by obstructions (suspension transmission, exhaust, etc.... 2. Guide airflow purposely under the car through smooth ducts which create downforce Option 1 is much more common, but option 2 is what is used on professional race cars..... For the Z car, well, probably option 1 since not everyone has computation fluid dynamics capability on his or her PC a splitter is nothing more than a horizontal surface below the stagnant high pressure air right in front of the car.. this increases front downforce, which could make the car tail happy at high speeds........ for street cars, the general rule of thumb for the minimum speed the aero is effective is 60mph and above, although I designed an aero package for a specialized race car that needed downforce at speeds as low 25mph (it's top speed was about 70mph, so it's a different animal as far as how low is too low, full bodied race cars have between .5 to 1 inch of ground clearance and computer generated aero packages specifically designed for the car. for a street car, I would not run less than 3 inches

ZROSSA, Aero improved Z for the street... There in lines the conflict!! if you said Z for the track, well that’s different, but for the street, you must have sufficient ground clearance for driveways and speed bumps, not to mention sufficient airflow through the radiator in stop and go traffic. I think for a streetcar, the G-nose setup Tony-D spoke of is the best compromise, just add a vented hood BUT make sure the vents are at least 18 inches or more away from the windshield, otherwise you force more air into the hood due to the hi pressure region in front of the windshield (otherwise known as cowl induction)

Hey Guys, man this was a BAAAAD thread to come across while your at work!!! A couple things you need to address here. Aerodynamics are NOT an intuitive science!! so what looks good won't necessarily work well!!! There a too many interdependent variables and NOTHING IS FREE!!!! We are merely trying to minimize the losses created by a body moving through the viscous fluid known as "air" and harness some of its energy to our benefit if possible So first of all, some clarifications: 1. The concept of two air molecules starting at the same point traveling around opposite sides of a smooth body and meeting again at the back of the body is known as the "Kuta Condition." This is used in inviscid flow theory along with Bernoulli's methods as a way of "characterizing" the function and flow of air that we cannot explain directly. The other concepts mentioned pertain to "downwash" which is a more Newtonian concept of redirecting the air that is used in conjunction with inviscid flow theory to estimate aerodynamic loads. Because we are not able to measure EXACTLY how air functions all the time, we deal in generalities that allow us to approximate what is going on...it is a very artistic science as a result..... 2. Given the concepts of #1, an automobile is inherently lifting off the ground due to it's shape being like a wing. The top of the car is longer and smoother causing the air to move faster over it than under the bottom of it. Add to this all of the obstructions and heat transfer from the engine to the air passing under the car which further increases its pressure, thus further contributing to lifting the car as well as increasing the drag resistance on the car. OK so if you can minimize the obstructions to the air passing under the car and better yet, speed up the air in the process, you reduce both the drag and the lift acting on the car...... So think of the underside of the car and the ground below it as a wind tunnel.....the air running under the car goes from a large area in front of the car to a small area under the car which (if it doesn't contact any obstructions) will speed the air up and lower its static pressure. This is the function of a smooth belly pan under the car, but nothing is free, so now the air under the car is moving much faster than the air around the car and specifically behind the car so if this fast air runs into the slower air, you "choke" the air flow which will greatly reduce the effectiveness of your belly pan. You must then find a way to slow the fast moving air down back towards the rear of the car increasing its pressure back to the rest of the air around the car without effecting the air behind it still moving through the "neck" of the tunnel under the car. Hence the need for the diffuser which allows the air to smoothly expand and slow down to the speed of the air behind the car, which if done correctly can even help to "suck" the air out the back of the car..... The Diffuser DOES NOT create downforce, it increases the effectiveness of belly pan.... This is the baseline to start with.....a continuous smooth surface that runs from a large space at the front of the car, necks down smoothly to a small space at the middle of the car, and expands smoothly to the back of the car. If you add skirts to the sides of the car, you box in the tunnel, further increasing it’s efficiency…. The arrangement that ZR8TED has is beautiful, and I dig it, but it is more of a rear wing than a diffuser, thus he will get rear down force benefits, but not see the drag reductions thus will need more power!!! This explanation is the benefit of an aerospace engineering degree... The detriment....action movies seem really stupid and borring to me!! Cheers, Ian

I believe that MSA is working on distributing the hoods for the manufacturer so keep an eye out for them.... cheers, Ian

There are several guys on the west coast that currently sell carbon hoods and deck lids for 70-78. I have seen a carbon hood on a 240 (my friends) it looks great, all be it a bit ricer, and cut almost 30lbs out of the car. All the race guys out here are scrambling for these things the hoods are going for 300 to 600 bucks just FYI cheers Ian

Just go find more valves for the N42 (I think the N47 uses the same valves but do yourself a favor and check out the Geocities site) Even if you have to buy new valves, they are still available and not too terribly expensive..... that is DEFINITELY or best bet!! good luck, Ian

yank the 240 motor and drop in the 280.... take the distributor, intake, exhaust and fuel pump off the 240 motor and bolt them on to the 280 motor.....they will bolt right up that is the easiest way to get going cheap and it should run real strong..... if you could get the FI setup installed you would get better gas milage, but I have a stock 280 with SU carbs, header and a 280ZX distributer on my car and it runs great!! just my 2cents good luck Ian

Hey Pipelayer, I'f your only using the SUs for now, Why do you need an early balace tube?? Just cap/plug off all the smog stuff and your good to go!! If your in So Cal there are those of us that can help you out..... Cheers, Ian

I knew there was a 1/2 in there somewhere....

As john mentioned, bigger bar in the front makes the car understeer or "push", bigger bar in the rear makes the car oversteer. Suspension setup is about the most subjective thing on a car, especially a street car with an inexperienced driver (speaking for myself) If you are happy with the car's handling without sway bars, no one says you have to use them, there a pain!! you are running really stiff springs for the street (stock rate is 140 lb/in front and rear I think) but if the car is not too twitchy, and you like the way it feels, leave it!! If the car still has more body lean than you want, try using the stock front and rear bars off the 280Z. The motorsport and Sus Tech sway bar kits are HUGE in my opinion and designed to work best with soft springs, so they may be excessive in your case given the spring rates your running..... just my 2 bits...... good luck!!

not to step on Zline's toes here, but I think the 280 springs are the same diameter as the 240, the rears are just longer. I have seen people use the 280 springs on the 240 to give it a nose down rake rather than the standard rear squat....... Also, I don't think the 280 suspension is interchangable with the 240 given that the 280 has taller rear strut towers, but I may be wrong... either way, if you plan to throw new stiff springs on, I HIGHLY recommend doing urethane bushings and tokico struts while your in there otherwise you just wind up with a stiffer riding unresponsive Z.... good luck with it either way....

Are you using the stock springs?? If so, most guys switch to an adjustable coilover setup with 3.5" springs instead of the stock 6" diameter (not shure about the exact coil diameters by the way) so you gain an 1 to 2 inches in tire width without adding fender flares Or am I understanding what your trying to acomplish??

By the way, if you are using CV half shafts, using this diff mount accentuates the tolerance issues between the rear swaybar, swing arms, body and half shafts by limiting the swaybar travel (hits the diff before droop)...so be aware!!!