Thanks beandip, now that you've mentioned it I think ive seen a scan of that page on the net somewhere. Did it have a drawing of the Zed over a grid ?

Steven

Originally posted by RB30-ZED

Id go with the brake ducts, as they look better, but if you dont need them block them of from behind to stop air getting under the car.

Steven

My 240Z that I owned in the late 70's through mid 80's had a Airdam without brake ducts (see my Gallery), and my current 240Z has one with brake ducts. I believe that I'll be going back to one without brake ducts before she gets to a paint shop. I thought my tastes had changed, but they really haven't. I like it without ducts.

bkiller I dident ask about the air dam but thanks for the info. rb-30-ZED , no it is different I dont have a scanner or I would send a page . This is a report on three different cars and as a compairson the '70 240Z , OPEL GT , MGB GT one and a third pages of results of testing of the three cars. as far as down force vs lift. the Opel GT front 130 lbs of LIFT and rear 155 lbs of LIFT and 230 lbs of drag. The MGB GT , front 70 lbs. LIFT and rear, 130 lbs LIFT and 285 lbs of drag. I don't know if any of this is of interest but I just thought I would pass it on I found it interesting because these were the cars of the era that were in compitition. All were priced at or near $3500.00 .

Steven, your proposed test sounds interesting, let us know the results if you can. On air flow over the hatch, the difference may be that over the bonnet the air is physically forced to speed up and hence lose pressure, while over the hatch air merely moves in to fill a lower pressure area. The bonnet being the forcing physical object therefore is subject to lift, the hatch is passive in that regard. But there is a fair dose of conjecture in this.

Beandip, good stuff but are you sure that the Z had pressure on the bonnet? The usually accepted situation is that there is lift there, eg see Steven's and my posts.

Originally posted by 260DET

On air flow over the hatch, the difference may be that over the bonnet the air is physically forced to speed up and hence lose pressure,

I would disagree with that. If you lose pressure over the hood, than ram-air systems wouldn't work. Same with the cowl-induction hood scoop, which uses the high-pressure air from the front of the windsheild.

Originally posted by 260DET

while over the hatch air merely moves in to fill a lower pressure area.

Move in to fill a low pressure area ( how did it get there?):classic: or was it that it was accelerating down the hatch to fill a increasing area that the low pressure formed in the first place ?:classic:

Steven

down force is what the tests show no kidding. I will look further and see how many other tests include this sort of data. The test I am quoteing also shows the G-forces and degree of lean on turn at speed , compaired to other cars. The Z showed 1.03 hp per cu Inch. but I think that was at the flywheel. I dont think the early Z had 150 HP at the rear wheels.

Oh yeah?

TheL28 engine has175? cubes and 175 Hp, according ther the plate on the fenderwall.

And I still can't spin the tires unless the road is wet. :disappoin

What, is it auto?

Originally posted by TomoHawk

Oh yeah?

TheL28 engine has175? cubes and 175 Hp, according ther the plate on the fenderwall.

And I still can't spin the tires unless the road is wet. :disappoin

If it's not an auto, you need a tune-up, or new clutch, I would think.

Yup. 3 speed auto,rebuilt, with the low first gear and 3.54 diff. Definitely need tuning (runs rich). Pickup off the line is not bad tho.

Tomahawk what we are talking of here is the 240 shape Z and the tests that were done were on the first of the Zcar . The facts that I have been refering to are for this car . Namely the '70 240 which were less than 2800ccs. Dont believe what you read on the plate. There is no way the engine ever made that HP at the wheels. Yes at the crankshaft on an engine stand with out a alternater or water pump or any other add ons. Figure about 135 HP on a good day at the wheels.