pparaska

Evan I like those wheels alot better as well. The paint on your car is SO SWEET, that putting a really shiny funky rim on it takes away from it, IMO. Those wheels really look great on there. What are you doing for an engine these days?

O.K. call me fickle, I'm lining up with Terry more now. Yeah, the drag could be a slight effect (due to higher speeds for the last 1/8th mile), but the issue of more torque being TRANSMITTED to the wheels with the gearing, tire size, etc. taken into account as well as how much torque is available at the flywheel during that last 1/8th mile seems to clinch it. I think (I shouldn't do that). If you use the rule of thumb from the page that Terry posted about "It's better to make torque at high rpm than at low rpm because you can take advantage of gearing" seems to hold true for the L28T during the last 1/8th mile. I think, just a feeling right now, I haven't really bought into it yet . So I guess my question is, if Scottie went to a 3.9:1 diff, he'd be turning 6200 rpm at 122.5 mph. I don't know what the torque curve looks like for his setup, but I'd be surprised if it's down too much at that rpm. In other words, would it make sense to use more gear (higher numerical diff ratio) if the engine is still pulling (not down on torque) at 6200? Seems like there'd be more torque available under the time curve from 1/8th mile to 1/4 mile this way, and that's what would accelerate the car more (and offset the drag a bit ). Probably just another brain fart. ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

Pretty cool! A recent Hot Rod or Chevy High Performance had a section with V8 Corvairs in it. What blew me away is that they were quoting weight numbers like 2500 lbs for the car with V8! I had no idea they were that light!

Mike, those wheels and brakes look GREAT! Does that bracket by any chance have the same function as the old Z-Quip Bracket? Used late 280ZX disc and rotor (I think)? Or was it early 280ZX? Anyway, it looks like the same dimensions, roughly. I wonder if Z-QUip is still around and making them. They were like $130 a pair or something, 5 years ago.

John, you crack me up. Yeah, the "jerk" put out by the L28T was higher, that's why it "jerked" more in the last 18th mile. Yeah, that's it .

I'm thinking along the same lines as Drax. The total drag is proportional to what, the cube of the speed? That ~10 mph difference at the 8th between the two drive trains/tires might be all in that aero factor. I know Aero Drag = 1/2 (density)*Cd*Area*Vel^2 But doesn't road and drivetrain friction account for another power of Vel. proportional drag, making the effect of vehicle velocity on drag somewhat more like a cube power dependence? Inquiring minds want to know. Pete (I ain't no aerodynamicist) Paraska [This message has been edited by pparaska (edited February 12, 2001).]

Scottie, no hurry on either set. I just wanted to get in on this one time kind of thing, as I doubt I could duplicate it for the $$. I have one set promised to a friend, and the other is "just to have", or in case I build another hi-po Z (doubtful - 1 toy for me ).

Jeromio, you're probably still in good shape. The stubs aren't really matched to the struts or anything. There's some variance in them, for sure, but probably smaller than would matter. The issue is to use the correct spacer or distance piece between the bearings in the strut. The only ones I've ever seen are the "B" ones, the middle of the tolerance range. Check to see what is stamped on the strut housing (I can't remember where it is stamped, but it's on the outside of the casting I believe), and make sure the letter on the spacer matches the strut. BTW, the spacer marked B usually looks like an E, since it's hard to make a letter from a flat letter punch imprint well on a small curved surface. Anyway, an A or C wouldn't be confused with a B that looks like an E. When I put stubs in, I install the inner bearing first to get the stub going in straight (at least I can eyeball the end of the stub in the center of the inner race). Of course, this is after packing the strut housing with grease. Put the spacer and any copper washers that were there on the stub axle, grease the outer bearing, and start tapping it in, using the inner race as a guide to keeing it going in straight. If it's not going in easy, then find out why. You don't want to be hitting that stuff very hard, as it will ruin the outer bearing. The stub will end up pushing the bearing back out. Go slow and tap it back in around the inner race with a brass drift, being careful not to mar the threads or splines. This way, you will get around the problem of installing the inner bearing after the fact when the stub and the strut housing are both resisting you. Also, when reseating the inner bearing while and after the stub is in, tap around both the inner and outer race with a brass drift. This way you are tapping on the inner race and outer race alternately to keep from loading the ball bearings against the sides of the races too much.

You guys are confusing me. The bearings on the stub axles are ball bearings with the outer race as a non-removable part of the bearing. The outer bearing is sealed on one side, the one that goes toward the lug stud flange. The other side is open. The inner bearing is open on both sides. When you have a machine shop swap the bearings, you might want to point out taht one side is sealed and goes against the flange. They know that, but it's good to just be sure. They should have a bearing splitter plate to go in behind the bearing to press it off. And seriously, if you're going this far, have them shot peened and magnafluxed to check for problems at the flange/axle weld and at the splines. The peening will close up stress risers as well. I believe this is what the NISMO parts had done to them to make them stronger than the stock ones. [This message has been edited by pparaska (edited February 11, 2001).]

A tip I got out of the "How to Restore your 240Z" or whatever from Wick Humble was to use Naptha on a rag to de-stick adhesive. Works most of the time, and is alot nicer on things than carb cleaner. I do use carb cleaner spray as a nice solvent though . You can get Naptha in any hardware store in the paint section.

Terry, I believe that what you are saying is true IF the same lettered strut housing and spacer are used. Like you said, if you haven't swapped housings or spacers around, I think you'll be fine.

FYI, I got email back from Dave Williams dave.williams@chaos.lrk.ar.us His site is FULL of interesting stuff, especially for the FORD guys. I haven't gone through it all yet, but looks like several hours of browsing!

Mike, I'm pretty sure the brake caliper won't fit in back of the stub axle, and you'll need to put the brackets on with the caliper in front of (LEADING) the stub. Try mocking it up to see if the caliper will hit the strut tube with it trailing. The other issue is hose length. Try that both ways as well. I'm 99% sure any disc setup on the rear will have to be put on LEADING.

If you are using the same spacer between the bearings and the same strut housing, that both have a letter (A, B, or C) stamped on them, and the letters are the same, you'll likely have not problem with preload. The letters are used to handle the slight manufacturing variation in the strut housing and the spacer is used to match to 3 different ranges of measurements in the race-to-race distance in the housings. I usually just give the stub a whirl with my hand after torquing to see if I think it's binding or really loose. A spring scale is just like a spring type fish scale that you hang a fish on. It measures the force that is needed to rotate the stub at a constant speed, and therefore, a preload drag torque. I suppose with a little bit of calculation and using a small torque wrench at the right angle on the stud, you could duplicate this test. There's an excuse to buy a tiny torque wrench! Hope that helps, ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

Wow, this is getting away from the original topic a bit, but no biggie. Tom, the car in the CHP mag went quicker and faster through the quarter but was less consistent with the manual (0.032 sec spread versus 0.007 with the auto). I was kind of expecting the auto to be quicker. I don't have the numbers off the top of my head, but it was around a mph faster, on average with the manual, and around a tenth? quicker? Of course, if you're racing brackets, it'd seem the auto is the definite winner since you'd have much less chance of breaking out. The crowd at the test enjoyed the manual car more than the autos. I guess the rev limiter at the tree bouncing at 6000 rpm, then dropping the cluthc, and the 7200 rpm between power shifts helped make it more interesting to them .

I've heard that the best shifter (not sure if this is the best for dragging, road racing, or street) is the Pro 5.0 shifter. They're made for the T-5 (not sure about the ZXT one, but it ought to be the same?), the Tremec TR-3550 and TKO, and a few others, maybe even the T-56. I know that I've heard that the B&M one rattles alot, if that matters. [This message has been edited by pparaska (edited February 10, 2001).]

Jim, you're talking about Dave Williams, I'll bet. What did he call it? Tyranosaurus RX-7? Dave's a really sharp DIY guy that definitely doesn't care if his stuff is unpopular. He used to post on the racefab and defunct hotrod email list of yore also. Last email address I have for him is: dave.williams@chaos.lrk.ar.us The address I have for his old web site is NG anymore.

Norm, good point Tom, there's an interesting comparo in the latest Chevy High Performance wher they raced the same car first with a drag built light-weight rotating component TH 350 automatic, and also a racing 4 spd Jerico. Very interesting. The stall converter took about 30 hp away at top end (7400 rpm) due to converter slip. The guy also had to rev to 7400 with the auto versus 7200 with the manual to get teh same trap speed.

Tim, thanks. I sent $120 using his email address as in his profile here.

Jason, thanks! I knew the answer you gave (the in-depth engineering answer for suspension dynamics) but was hoping racers used some sort of rule of thumb with less inputs and calculation.

Scottie, I want a pair. So are you still doing PayPal? What name do I use to get in on this? Or should I send a money order? Address? Thanks for doing this! Pete

Morgan, are we so feeble that you just can't stand us?

Lone, I don't think subframe connectors are part of the debate here, just kinked (and supported at the kink) door bars.

I was around a V8Z (actually it's the 377 ci Gnose Black w/ White striped one that's been seen here) at the Atlanta Convention in 1995. Mr. K. (Z car "creator") saw it, loved it, and signed his name to the dash, I heard later. That's what gets me. If Mr. K sees no problem with a V8 Z, why should anyone else? ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages

Ditto. You'll see that much less than 250 lb/in on the 8" coil and you'll probably bind. But Mike, can you use a longer coil since you're using camber plates? How about using a really short spring perch as well? Anybody know how to figure dynamic compression of a coil spring if you know the weight on the spring? I mean, I know how to calculate how much the spring will compress from free length to ride height if I know the corner weight, but how do you calculate how much the spring will compress past that if you hit a bump and are going around a corner. In other words, how do you figure the compression from all the rest of the dynamic and cornering loads? [This message has been edited by pparaska (edited February 08, 2001).]