pparaska

Any 280ZX V8'ers out there want to let us know if the 280ZX chassis is stiffer/stronger than the 280Z? I'd bet that a 400 hp 350 would be o.k. without alot of mods, but an 8 point roll bar, tied in well would be a good idea. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Leonard, First off, the way the board works here means that newly updated topics show up at the top of each forum, so if it's responded to, even months later, everyone is aware that it was. Of course, the new post to the thread will be at teh bottom. I always go to the bottom and see what's been added. I think most people do as well. This is a MUCH better way than the way zcar.com works, as you have to go way back to see if a thread was added to. Some threads even a day or too old on zcar.com don't get looked at and the thread dies before it was finished. This is one of the things I hate about zcar.com (aside from the incredibly childish behavior of many of the yoyos that get on there). Anyway, As far as master cylinders (MCs), you need to be aware of the stroke of them as well as the diameter. If it's 7/8" for your datsun slave and GM "M-21"-ish fork, that may or may not be enough, if the stroke is too short. Realize also that the stroke of the cylinder doesn't have to be much beyond 1" (if any) in the Z, because the pedal ratio: (length of pedal to pivot) ------------------------------- (length of MC clevis to pivot) Is 6.2:1 versus the normal 4:1 for many American cars. If you have 6 inches of pedal throw (I think this is close to what you have in a Z, with the pedal stop and rubber remaining), then you need less than 1 inch of stroke capability in the MC. Most MC's have at least this much throw (including the short ones from AP Racing). The upshot is that if 3/4" diameter is almost enough to disengage the clutch enough (sounds like it is) than 7/8" ought to be enough (1.36 as much fluid being moved by a 7/8" diameter versus a 3/4" diameter MC). Just make sure the 7/8" has enough stroke. My guess is it will. Try to measure how much the clevis moves when the clutch is fully depressed to determine the stroke needed (add a bit more for safety). ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Lone, THANK YOU! I love it. Technical content from someone in the know. PLEASE keep it up! I had no idea DOM was ERW tubing taken over a mandrel. I didn't know how it was done, but supposed it was hot solid bar taken over a mandrel. Duh. Thanks for setting me straight! I think if we ever do get an FAQ going on this site (Hmm.) this post goes in straight away. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

I used brass compression fittings on the 3/8" aluminum tubing, connected to a brass pipe fitting into either a hose nipple (for fuel hose) or a NPT fitting into a Holley regulator. I hope this is a good way to do it. I will be checking for leaks when I get fuel in the tank before the first start of the engine, and pressurize the system. If you do flare it, you should be real careful when flaring the aluminum tubing. Get out the magnifying glass and inspect the flare for cracks. They can only grow. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Yes, I was concerned when I got the bar kit. I was hoping for DOM, but that's usually more expensive, so I wasn't too surprised. I guess I'm curious now about the seam in the tubing. It sure does look like it has a (laser?) welded seam on the wall. I know DOM is preferred, but is the seamed mild tubing in a .134 seamed tube that bad of a thing to make me run from it? I guess a talk with an independent racecar builder is in order - hmm. There are a few in my area that I will call. As far as pictures, there's a decent one of the outside wall of the tube in the area that looks welded at: http://members.home.net/pparaska/image/structuralmods/S&Wtubingouterwall.jpg And a out of focus (sorry) photo of the inside of the wall at: http://members.home.net/pparaska/image/structuralmods/S&Wtubinginnerwall.jpg http://members.home.net/pparaska/image/structuralmods/S&Wtubinginnerwall.jpg On the inner wall, there is a definite raised line along the tube.

Morgan, I'll take a pic of the tubing tonight, inside and out and post a pic of it so you can see. My lame ass mechanical engineering mind only knows of DOM as being the only way to make seamless tubig as well. O.k., I guess you could bore a piece of solid round stock, but that doesn't make any sense (unless you're making a gun barrel, etc.) My experience with tubing is nil. But it sure looks like it has a seam in it to me.

The struts (actually the springs) hold up the car, and the frame rails at a set height (with the car not moving). If you put in the crosmember spacers, it lowers the crossmember and the engine. There's a thread or two on this. I know others have had a hard time seeing this (I thought it worked the way you said at first glance also), but this is how it works. Draw a free body diagram of the car and you'll see what I mean. The tires, wheels, strut tubes, springs, and strut towers hold the car above the ground. For a set tire size, wheel size, strut tube length (whether it's been cut to shorten it), spring perch height, spring stiffness and free length, top perch/isolator height, the height of the strut tower sheet metal off the ground is fixed (if the car is not moving). Therefore, the frame rail is also at a fixed height. Having or not having the JTR crossmember spacer block between the frame rail and the crossmember dictates teh crossmember and engine mount height for a fixed tire/wheel/strut/spring/etc. assembly. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Andrew Bayley wrote up his experiences about putting his S&W 8 point cage in at: http://24.4.88.29/ubb/Forum6/HTML/000120.html But this 8-point doesn't have A-pillar tubes, just door bars forward of the main hoop.

Mikelly has somewhere between 500-550 flywheel horsepower, according to Desktop Dyno, his builder, the performance of the care, etc. Just my opinion, but I think you really ought to consider building an engine from the ground up or going with a builder's crate motor. It doesn't have to be expensive, but you get to spec stuff like forged pistons, H-beam rods, steel crank, splayed 4-bolt mains, the right roller cam, etc. to get that 550 hp from a normally aspirated, pump gas motor. If you ever do juice a motor like that, you could do it knowing that it'd hold up, not have to worry about hyper cast pistons, etc., that the ZZ4, ZZ430, have. Great engines, but if you want more power, I'd upgrade the bottom end now to handle it. Built SBC, done right, are not that expensive to build. $5000 should set you up pretty good. If you really wanted more power, you could add a blower (ATI, whipple, etc.) later to get it. I've been real impressed with what I've read about several of the crate motor companies. Beck Racing engines has a 550? hp 383 they sell that looks sweet. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Ross, I had the 1/2" spacer in at first, but in trying to get the driveshaft u-joint angles below 4 degrees and equal, I found I had to raise the front of the engine, so I yanked the spacers. BTW, my buddy with a JTR'd 240Z with the spacers installed and a stock pan and the car lowered about an inch hit a 3-1/2" high man hole cover (road was ground down being readied to be repaved) and took out part of his pan just last month. Yikes! ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Morgan, I have the kit (not installed yet). It doesn't fit very tight to the sides (the main hoop), and it's not easy to find a good way to put it in if you want to keep the stock seatbelt retractors. Search the Chassis forum, and others, as this has had alot of discussion. I seem to remember there was another kit that was better, but I don't remember the particulars. I think the S&W is better than the Autopower rollbar though, as that thing bolts to the thin inner fenders, which doesn't do much for stiffening the car.

I got mine from Mcleod, through DarkHorse, where I got my Tremec, etc. It's a standard piece for a GM T-5, etc. About $259 though!

Man, that'd be a tough one for me. I'd be really prone to wanting that engine back all the way too. Something cleaner about that install - no crossover at the firewall, no u-joint in the steering, the CG. would be farther back, etc. But practicality might win me over - add a u-joint and just bolt the engine in with the OE manifolds and crossover. I'm no help, I know. Sorry ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

With a J pipe, you get a 180 degree bend and a 15" and 6" leg on each end, hence the J (for Hooker pipes anyway, from Jegs, Summit, etc.) I probably bought 8 of these, I could probably get by with 5 or 6 to do it again. I have 10 flanges in the system, not counting the headers. 2 at the headers, 2 at the ends of the head pipes, 2 at the front of the X-pipe, 2 at the ends of that assembly, 2 more at the short pipes to the mufflers. These things add up in cost also, I can't remember how much, but they weren't cheap either. BTW, cutting the system into 50" long pieces allowed me to get it coated, as the coaters have a length restriction of about 54" (Baxter Comp. Engineering does anyway). I would guestimate/measure how much of a turn I needed (sometimes using a piece of cardboard, protractor, etc.) After a while I got pretty good at eyeballing it (something like 25 separate bend pieces in the entire system!) and I'd cut off a piece with a little more of the bend than I'd need, use a hose clamp around the pipe to get a straight line around the pipe, cut it with a hacksaw. If it was too much of a bend, I'd redo the line around the pipe, and use tin snips to trim it back. BTW, where I had several bends butt ended up to each other and I was fitting things together, I'd use hose clamps to hold the ends of the pipes together while I measured, etc. This system took probably 80 hours total to build. I work very slow and meticulously at stuff like this. After that kind of investment in time, I decided to stainless/ceramic coat the entire thing (except the mufflers and the short pipes going to them) to save it from rust and to keep the heat in the pipes (hopefully). I spent several hours leak testing all the pieces before sending it to the coaters (BCE). ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Mike, Yes, butt welds. Lots o' Fun. I probably spent $150 on a bunch of steel mandrel bend J pipes, maybe $30 on the straight stuff. I don't know how much of noise attenuation you'd be able to get with a tunnel mounted muffler under the driveshaft, as the tunnel's so narrow. It ought to act like a crossover though. Maybe several small ones end to end?

I think if you rough up the stainless and hit it with some self-etching primer, then use the SEM brand blackout paint for this purpose, it works pretty good. Then again, powder coating would probably be best. I was considering powdercoating the window frames in the doors and those emblems and just leaving out windshield and rear window trim, possibly cutting the lips off the gasket that hold in the trim. My bumpers and door handles are going to be body color. I think you'll need some cement or sealer on the windshield and rear glass gaskets or you'll have leaks for sure. How about that messy black windshield sealer that doesn't cure? It's no fun to clean up but at least it comes off with mineral spirits. The Gorilla snot stuff breaks down well with Naptha though. As far as the vent cover emblems, I've actually had them just fall of on a exit ramp before . I think the only other way to get them off would be to put a wire through the center and yank on it. The wooden stick (paint stirrer, etc.) worked for me though. They have a spring clip on the studs that stick into the car.

Drip rails: Put a wooden stick between the body and the rear end of the drip rail moulding and pull out and up. Once it starts, slowly work forward. Windshield and Rear window trim: That's really best done after you take the window out of the car, if that's what you are going to do ultimately. That way, you can flex the rubber and the trim comes out. If you aren't taking the glass/gasket out, then you have to dig with a screwdriver. Start by taking the corners out. Then SLOWLY and EASILY pry the straightish parts from the ends. This stuff bends (permanently) very easily and if it does, it's very hard to get the dent out of it. Thinking of painting it black or something? Badges on sail panels: Wooden stick under the edge of the emblem. Go in diamentrically opposed places, and where the posts are that hold it in (not sure where they are, left and right I think.

I put alot of thought and effort (and $) into my exhaust. Check it out at http://members.home.net/pparaska/exhaust.htm I'm not saying this is the best way to do it, but that's my method. No, I haven't started the car to hear it yet . ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Please note that I don't have a resevoir for that 1" MC anymore, and a new one is $50 from Truechoice Motorsport in their 2000 catalog. That English race stuff is expensive.

If anyone needs a 1" clutch master cylinder, I have a short AP Racing one that was only used for 20 pedal pushes until I determined I needed less diameter (I'm using a hydraulic throwout bearing). It's a pricey piece - $168 for the master cylinder without the resevoir. (I don't have a resevoir for it anymore - but they are $50.) The nice thing about the unit is that it's a bolt in (after you rethread the clevis on the pedal) and allows the WW bottle to stay in place. I'll let it go for $75 plus shipping. I'll throw in a rebuilt kit I have for it also. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Just a half inch on the left shaft would be plenty. Actually, that and use the "stick" and outer joint from another left CV shaft and the inner joint from a right shaft in the right side of the car and you'd gain 1/2" of endplay there as well. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

In the latest (DEC 2000) Grassroots Motorsports magazine, Corky Bell has an article on turbo hop ups where he says: "The lowering of the engine's compression ration can remove heat, too. This is a last resort, as it tends to produce an unresponsive slug if done to excess. Never, but never, consider anything under 8:1." BTW, it's a good article (definitely too short) and a good magazine with lots of tech stuff every month. This month they did an article on engine swaps in general. Very interesting. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Mike Kelly probably knows for sure, but that 350 is probably a 4 bolt main. Yes, is a Chevy small block. Welcome! ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

Cool, I remember seeing those a while ago. Scottie, did you through bolt the CV shaft to the modified companion flange, or is that big hunk of steel threaded? Seems like there is no room to through bolt and you'd have to thread into it. ------------------ Pete Paraska - 73 540Z - Marathon Z Project - pparaska@home.com">pparaska@home.com -

WOW! That RX is sweet! Talk about a crammed engine compartment. I love how sleeper it looks. Man that must be fun to play with on the street!