pparaska

James Thagard (the astronaut's son of Zcar.com fame has finally let teh cat out of the bag and told us the parts needed to put together a set of CV halfshafts that will mate the Viscous LSD diff of the SS 300ZX to the 280ZXT companion flange. The info doesn't look entirely complete, but his site is: http://www.eng.fsu.edu/~jthagard/ Look for the VLSD note in the lower left of the page. I just don't know what the reference to a spacer is all about. I don't know if the AMC shaft needs to be shortened either. Pretty inventive swap though. Still uses the smaller 240Z stub axles also.

I'd find out what Mike kZ has since that's a better more integrted system. The evaopator core/box and thermostat was $250 from Curtesy Nissan (ouch!) The compressor I got used, so I don't know. I'd figure $100 ought to get you there. The hose kit was around $50 I believe. The condensor was about $120. You'll have to come up with mounts for everything but the condensor which comes with them. I used the old mount for the evap box I had. Courtesy could probably get you one of those also. I'm too old to do without A/C. The D.C. area is so hot and sticky in the Summer.

I put AC in my 73. I have an old 327, but the only difference that might make is the compressor and brackets (simple to make). Here's the specs on my system: Sanden 508 compressor with custom brackets Vintage Air P/N 03250-VUC Horizontal Super Flow condenser, 12"tall x 23.9"wide x .83" thick (supposedly 40% more cooling capacity that an similarly sized run-of-the-mill condensor without the micro tube dual pass setup) This fits in the recess of the radiator support that surrounds the radiato opening. Vintage Air R134a hose/drier kit ARA under dash evaporator & box from bought from Courtesy Nissan. This is the same box the Z's came with when they had dealer installed air (I had an old one to compare it to), but it came with a R134 evaporator and expansion valve and a thermostat. I have a GT Mustang cooling fan to help pull through the condensor I also sealed the radiator to the core support and the condensor to it as well. All air entering the condensor must go through the radiator core, and all air pulled through the radiator core must enter through the condensor. The most important part of this setup is the Ford 1985 Full Size LTD blower fan and motor I cobbled into the 240Z fan box. I also sealed the connection between the fan box and the evaporator box well since it is a suck through evaporator setup. This fan pulls about three times as much air as the 240Z fan, by my sloppy experiments. I don't know how well it works since I haven't driven the car yet (paint jail right now - June 2001), but I'll have it done this Summer and report on it. [ May 31, 2001: Message edited by: pparaska ]

The 280ZX version nut, PN 43262-W1202, is a clinch type lock nut that does not require the peening the 240/260/280Z nut requires.

Scottie, put the URL between the following: {url} http://url.here.com/index.htm {/url} Except change the curly brackets to square brackets.

Just so you know, the 280ZXT's did not have LSD R200s. But the CV shafts and companion flanges are worth keeping...

Fast frog, a PCV or scavangeing pump can actually help ring seal and power, since it creates a vacuum to help pull the rings down on the ring lands, reducing flutter, etc. Granted, a PCV won't do much at WOT since there isn't much vacuum to the PCV to pull vacuum into the case, but a scavenging pump doesn't have that problem. Plus, a PCV robs no power, and it helps get the "bad" gases out of the crank case to help keep the oil clean. [This message has been edited by pparaska (edited June 23, 2000).]

jeromio, Sorry I missed your post. The bolt circle (4 bolts) of the 280Z (or 240Z) companion flange is less than 3.5 inches in diameter. The bolt circle (6 bolts) on the CV shafts is more like 5 inches. Ain't no way they can mate without an adapter or a plate welded to the 280Z companion flange to make it's diameter larger to accept the 6 bolts of the CV shaft. I guess you're confusing the bolt circles with one another. Hey, I'm a mechanical engineer, and I had trouble picturing the actual part from those drawings the first time I saw them! ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@tidalwave.net">pparaska@tidalwave.net -

If the auto manufacturers have a product you can source, I'd feel safe - as long as you can be sure it will bond to what you are filling. If it doesn't bond well, first, you get no structural benefit because it won't carry shear from one side to there, and second, it will leave a place for water to sit against the steel. But if you've had the rockers replaced and know the surface to be a good bonding surface (like an epoxy primer), I'd say using the OE sourced stuff is fine. If you're concerned there might be something (like rust, cheap primer, oil or wax based weatherproofing) to keep a good bond from happening, I'd leave it out, as it wouldn't help the stiffness. Cored structures usually use the core to transfer shear from one side of the filled member (the bottom of the rocker box for example) to the opposite side (the top or the rocker box). Bad bond = no shear transfer = no stiffening. (Of course, there are varying degrees of bond, and therefore stiffness). The cored structures I have experience with are sandwich panels, and things built out of sandwich panel techniques. That stuff was built from premade foam sheets and woven fiberglass and carbon / resin skins. Very stiff indeed, for the weight. As for why the golf club works better, is exactly as you thought, Dennis. The club head is closed and loaded normal to the club face. You filled it with foam which created pressure inside to counter the outer pressure, but you also put something with some structural stiffness in compression behind it also. The difference is that the rocker box needs stiffness in bending and depends on the foam for shear transfer to be effective, and the club head sees normal forces. (shear is easily understood if you take a piece of tape , stick it to a table on one end, and pull on it sideways on the other end - the adhesive is transfering shear from the tape's backing to the table.) Totally different application, in terms of the loading conditions. Oops, sorry for the engineering lesson. That was worth 3 CREs, if you are still awake . [This message has been edited by pparaska (edited June 22, 2000).]

Hi Jordan, welcome! The 300ZXT LSD R200 from the 87.5-89? will work if you swap the finned rear cover for the 280Z rear cover, and use the usual R200 mustache bar. And you need to take the driveshaft flange from a 280Z R200 and swap it for the one on the front of the 300ZXT R200. The 280ZXT CV shafts will work one of two ways: 1) use the modified 280ZXT companion flanges (as I outlined on my site and this site's tech articles) and the 240Z stub axles you have in your 73. 2) Swap to 280Z stub axles and companion flanges and either have the adapter I show on my page, or do the plate-welded-to-the-280Z-companion-flange mod that Scottie did. The 300ZXT shafts are too long. The brakes you use have nothing to do with the rear, halfshafts, or stub axles you use, as they interface with the strut housing and the lugs of the stub axle the same way, independent of which stub axles you use. It also non-LSD and LSD makes no difference whether you are using the CV or U-joint halfshafts. All these parts swap around. [This message has been edited by pparaska (edited June 23, 2000).]

Chris, I've checked them both out. Most agree both are far better than the Tremec supplied shifter, but some feel the Pro 5.0 is better. Most have the Pro 5.0 also. Thanks for the input! You can bet when this puppy hits the road I will let you know how it shifts!

Sounds like your rings are doing a hell of a job! Congrats! Are you sure you are getting vacuum to it? Does the baffle TOTALLY block it from the inside of the valve cover?

BLKMGK, it's in the car ready to go as I type this. I plan on getting the Pro 5.0 shifter (want to sell yours?) and use the Tremec-recommended GM Synchromesh fluid. Michael (HP Tech on these forums) has experience with the Tremec's and has said that breaking them in easily for 1000 miles and then changing the fluid, as well as again at 2000 miles makes them shift better. Yeah, I'll try it, but I'll be scanning for a good T-56 also. The Sallee T-56 for 85-96 T-5 Camaros looks interesting. They have an adapter plate in front of the transmission to use it on a Camaro T-5 or straight up Muncie type bellhousing. Unfortunately, the adapter is not available separately for putting it on your separately sourced T-56. But the picture in the August Chevy High Performance shows a simple flat plate adapter with holes. Something you could easily have made, once you had the two bolt patterns centered. They want $2295 for the T-56 and adapter - that would be an easy retro-fit for me, but the money is kind of steep. You do get the Viper tail housing on it for use with a mechanical speedo cable. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@tidalwave.net">pparaska@tidalwave.net -

Hardware store foam in a can has no structural benefit. The shear strength of that stuff is like cotton candy. Find out what the car manufactures use and use that if you are interested. Also, the bond to the steel of the car needs to be strong as well, or you aren't helping stiffness at all. Not to be snotty, but this is the educated opinion of an mechanical engineer that has designed things with foam core. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@tidalwave.net">pparaska@tidalwave.net -

What's really kick *** is that you can get the Fast burn heads on it and add the Hot Cam anc crank out 430 hp (I think?) The Fast Burn engine (ZZ4 woth the fast burn heads) is $3795 and puts out 385 hp at 5600 and 385 ft-lbs at 4000. Add the Hot Cam Kit ($175) and the power and torque go up. Granted, with boost on the V6, these number can be exceeded, but to get the low speed drivability with the turbo, alot of fancy stuff is needed, no? I have one turbo car (92 Eclipse GSX), and yes it's stock-ish. But it's real finnicky about combustion chamber cleanliness, heat soak of the intercooler, high octane fuel, low ambient temps, etc. I know all this is correctable with a complicated and expensive aftermarket set of boost controller, intercooler, etc., but I chose not to have that hassle in my Z. Maybe I've got it all wrong here and the GN stages are forgiving for these factors. Scottie, can you educate me? ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@tidalwave.net">pparaska@tidalwave.net -

You guys seen the new (July?) Chevy High Performance with the article on a custom bellhousing and an adapter to bolt a non-LS1 T56 to an early SBC with the pre-T56 flywheel/clutch/etc.? Hey, I guess I could get that adapter and bolt a T56 to my blow proof (straight up) bellhousing? Hmm. That Tremec may have to come out sooner or later so I'm thinking. Anyway, thought you guys might be interested. BTW, Chevy High Performance has better tech article content that HotRod, Car Craft, etc., I think. I subscribe to HotRod and Chevy High Performance, and I like the tech content in CHP much better.

Mike, Tom(?), please excuse me while I wimper looking at the Tremec (yet untested) in my car. Pete "whipping boy" Paraska

Scottie - I love the black car and wheel centers! Beautiful ride! SuperDan, How about we put up a car of the month, with Scottie's as the first one?

Somebody calling themself "Max" on Zcar.com asked this question the same way, so I think I answered them there. Here's the response I posted there: I bought the wheels that are in most of the magazine pictures of Jim Biondo's car from Jim himself. (Jim has converted to 5 lug front and rear since then and now runs SSR Integral wheels.) He did all the research on how to get the wides 17 inch wheel and tire under the stock 240/260/280Z rear fender. Here are the numbers: Rear: and 17x9 with 149mm, 255/45-17 Michelin Pilot SX MXX3 tires. Note that on the rear, I have Jim's old brake setup that he had these wheel's custom made to fit. The brakes are Arizona Z Car's old rear racing kit with drilled solid discs on aluminum hats. The key is that the hat is 1/2" thick at the stub axle mating flange. So this 149 mm backspacing will be too large if using the stock brake drum by the difference of the thicknesses of the stock drum and the 1/2" thick hat on the Arizona Z car discs. With this setup there is just barely 3/16" clearance between the wheel and the coilover spring collar. I had to use an 8" free length spring with the coilover located at the top of the strut housing so that the tire would not rub the sidewall. The fender needs to be rolled about 1/4" (on my stock replacement 1/4 panels) to clear the tire. Also, be aware that if you go to another tire manufacturer or model, the tire sizes for a given designation (i.e., 255/45-17) change enough that the tires could be smaller or larger than desired. I think these tires are no longer being made. Front: 17x8.5 with 142mm backspacing, 235/45-17 Michelin Pilot SX MXX3 tires. 1/8" wheel spacer is used to get the tire away from a 2.5" coilover spring (Carerra). (and now to add a bit more content for the hybridz.org site BTW, I'm using Jim's old 280Z stub axles with 1/2-20 ARP long lug studs in the rear and 240Z hubs in the front with 7/16"-20 ARP long lug studs in the front. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@tidalwave.net">pparaska@tidalwave.net -

Andy, thanks for that post. I read it and picked up the phone and called Chad back at S&W to order my 8-point! Where did the rear bars meet the back of the car? I guess I need to pull teh gas tank? Any room to put the interior panels back after adding padding to the roll bar? Very surprised that you felt no difference with the door bar. Great war story!

John, I was wondering if you had other options as well. Here are my ideas (without knowing what your setup really looks like): 1) Larger diameter pulleys on the crank and blower? This would help increase the belt surface area. Of course, you'd want to keep the same diameter ratio as you have if you like it. Maybe there's not enough room for this. 2) Larger wrap angle on the pulley that is slipping? I'd imagine there might be an idler pulley, or maybe the blower is adjustable on it's mounts for belt tension. Again, just an idea, but if you could configure it for more belt contact angle, you'd increase the surface are of contact. 3) Custom Toothed belt setup (like the Roots blower guys run)? Bucks, I'm sure. Maybe something halfway affordable from another application might fit? Just a few brain farts, hope they helped [This message has been edited by pparaska (edited June 19, 2000).]

Frank, as you noted I don't have them in. They are used by JTR to add clearance above the transmission at the top of the tunnel. They will also affect the clearance under the hood latch bracket and the distributor. I think using them might aggrevate the clearance at the motor mount in way of the steering shaft, as it causes the shaft to be at more of an angle to the ground than stock, when you lower the crossmember with the spacers.

Actually, if the total offset with the adapters is kept to around stock, the wheel bearings see the same load. In other words, if a large offset wheel is used with a wheel spacer or hub adapter to get the effective offset to around zero on the early Zs, than the wheel bearings see the same apportionment of load. But that's a moot point. The issue is the adapter and wheel studs in the adapter have a higher bending load. It would take a very good billet adapter with very high quality wheel bolts in it to make it safe. Again, the lug studs on the car would see the same kind of loads as with a proper offset wheel, so that's not a issue. I've always felt that the adapters are an unwanted point of failure.

See my response to the thread "TKO???" at http://24.4.88.44/ubb/Forum7/HTML/000066.html in this forum. I have the TR-3550, also made by Tremec (before they bought BW transmissions). It is the little sister, torque-wise to the TKO. It bolts up the same though. It is a T-5 replacement, and a few make it in a GM form factor, if you need that. See my site for details on how I did the install. http://members.home.net/pparaska/TremecInfo.htm . Not a lot of detail on how to do it, but note that the Tremec TR-3550 and TKO are "straight-up" trannies, that is, they don't have the 17 degree slant of the rear trans mount pad. In other words they bolt up like a Muncie or T-10. I used a straight up blow proof bellhousing and the JTR crossmember with a spacer to raise the rear of the trans for the Ford rubber mount I used. One thing to note is that the stock shifter is known to be not so hot. A Pro 5.0 shifter is supposedly much better. [This message has been edited by pparaska (edited October 21, 2000).]

SpencZ, I'm surprised Mikelly hasn't chimed in. The TKO is the sister to the Tremec TR-3550 that came in the original mid 90s Cobra R Mustangs. It handles more torque than the TR-3550, due to larger input, main, and output shafts (i'm pretty sure that's how). Mikelly has told me that he has a buddy with a Tremec in a Stang (lots of mustang people put them in to upgrade strength from the WCT-5) and he says it's notchy as hell. I've heard this from others, although Mike at HP Tech says a good break in will have it shifting fine. I have a TR-3550 that was converted to GM use by http://www.darkhorseperformance.com . Forte's also offers this for the GM crowd. I haven't driven mine with the Tremec yet, so I'm crossing my fingers and I will change the GM Synchromesh at 1000 and 2000 miles as Mike at HP Tech has advised me. But seriously, I wished I had gone the T-56 route for the legendary shift feel and robustness of it's design. Afterall, even an extra 50 pounds isn't huge, and it's low at the center of the car, the best place. I appreciate the quest for light weight though. You are going farther in that respect than me.