pparaska

Scott, I agree on the over square thing. The area of the piston multilpies the instantaneous cylinder pressure. And going from a 350 to a 400 means 6.3% more area. Nothing to sneeze at. Add to that better valve unshrouding and you see more gains in the pressure. Multiply those gains together (Force = pressure * area) and you get a bigger push on the connecting rod. The above has to do with instantaneous and average con rod downward force. Rod/stroke ratio will play here too. Grumpyvette has explained this here before. Rod length affects the angle at which the rod's downward force is imparted to the crank pin, and it's relation to the pressure history above the piston. The actual reciprocating and rotating mass is not insignificant to how fast and engine will rev under load, but it can pale in comparison to the force imparted by combustion. Going to a short stroke to gain some kind of rev-ability is noble for F1, but in drag racing with a low rpm stall converter and certainly on the street, it can be a losing proposition. Yes, I'm planning a 406 at the moment. For many of the reasons stated above. Maybe I'm all wet.

I'd stick the Tremec TKO right after the T-56 for strength, and the Tremec TR-3550 right after that. Both Tremec's are stronger than a WCT-5.

Some like the CVs from the 280ZXT (and at least some 2+2s) to swap into the 240-280Z with an R200 installed. There are a few ways to do that swap. Check the right side of the menu on my site's opening page.

GAZRNR, that would probably be a bit of a fangle. Just an FYI, my spreadsheet uses functions that are in the "Analysis Toolpak". That isn't loaded with a standard install of Excel, so you'll have to add it. I think the easiest way is to go to "Tools", "Add-ins...", and select the "Analysis ToolPak". MSOffice will then ask you to put the Office CD in the machine to load the toolpak.

Mike, sounds like you missed your Prozac too I lost my bottle recently . Heck, give me Scottie-GNZ's car and I'd be tickled pink! Mike, glad to hear you DON'T want to sell you Z projects. You need to drive mine to revive your interest. Of course, it's about 150hp shy of what yours was. I'm working on that though (406 SBC in the planning stages)!

CVs (280ZXT). The slop is noticable between the halfshaft and the driveshaft. I know there's a bit more slop in the driver's side CV inner joint than the passenger's side, but you can see that the CV "socket" on the driver's side (that's attached to the splined axle) moves a good bit relative to the driveshaft. Not hateful, but I'd love to have less slop there - it takes away from the driving experience.

CVs (280ZXT). The slop is noticable between the halfshaft and the driveshaft. I know there's a bit more slop in the driver's side CV inner joint than the passenger's side, but you can see that the CV "socket" on the driver's side (that's attached to the splined axle) moves a good bit relative to the driveshaft. Not hateful, but I'd love to have less slop there - it takes away from the driving experience.

Mike, sorry I didn't get back to this thread. My Z has one of those hen's teeth 300ZX 3.7 LSD diffs. It's not really bad, and I'd be afraid if I messed with the gear lash it'd whine. I might try it if it gets to be annoying. I also wonder where the slop really is. Since it's a clutch type LSD, I'd think the spider gear preload would be taken care of. Maybe it is slop in the axle splines inside the diff or the spider gears to the case shafts.

Mike, sorry I didn't get back to this thread. My Z has one of those hen's teeth 300ZX 3.7 LSD diffs. It's not really bad, and I'd be afraid if I messed with the gear lash it'd whine. I might try it if it gets to be annoying. I also wonder where the slop really is. Since it's a clutch type LSD, I'd think the spider gear preload would be taken care of. Maybe it is slop in the axle splines inside the diff or the spider gears to the case shafts.

Perry, I drive a turbo car as a daily driver (92 Eclipse GSX). It's a great daily driver. But I absolutely hate the Jekyll/Hyde personality. Turn on the A/C, sit in traffic, and if the compressor's running, ITS A DOG. I know a trubo doesn't HAVE to be like that, but I wanted instant, full time (independent of ambient temps, etc., etc.) low end torque. I don't know of a cheaper more trouble free way to do that besides normally aspirated cubic inches. No slam to the turbo guys (I drive one!). I just wanted my torque served the very simple way, NA lots of cubes, for my Z! Thanks for sharing your story.

Let me just say that having an electric fan is not a sufficient condition for having cooling problems, although it may well be a necessary one, if a wimpy fan like the Black Magic 150 fan is used. Go OE. Ford Taurus 2spd, Mustang 2 spd. And I agree - get the air out of the system. Air next to the temp sensor for the gage will tend to make it read high - 20 degrees in my case. Once I got the air out of the system, it stays at 195 (same as my thermostat).

That sounds like how others have made their own design. I like the sound of it. I had the JTR mount for many years after making it in a press. I decided to go ahead and use it. Of course, I couldn't leave well enough alone. I used 3/16" plate on the top of the floor, some 1"x1/8" bar in front and behind it to create part of a "box" and connected it to the tunnel and my subframe connectors. I used 7/16" bolts through the plates and the mount, that are a snug fit, so it helps tie the car together a bit more: (Click for larger version) (Click for larger version)

Tim, I'd agree that even a 327 can be plenty. But mine's a bit on the high strung side. I've got plans in the works to just do a 406 SBC that will have more low speed response. Don't get me wrong, the 327 I have has good power, enough to impress most people, but I'm looking for stump pulling torque from below 2000 rpm, and I'll gladly let it top out at 5500 to get that. I guess I don't see a 383 being much more expensive to build than a 350 these days. We're talking maybe a few hundred bucks if that, and that's chump change by the time you get done doing the swap, and going through the brakes and suspension and wheels/tires.

I used the stock upper strut isolator. That forced me to 8" springs to keep the perch enough above the tire sidewall to just miss it. (This was all engineered by Jim Biondo, who I bought the wheels from and used his coilover ideas.) As soon as I find some round tuit's I'll try the 225 lb/in springs in the rear. The fear is that they'll coil bind on sharp bumps and dips. I have urethane bumpstops, so that should help. The 300 lb/in springs back there are too stiff for my tastes. I'd think you could use a camber plate or other top strut mount that was shorter than the stock strut isolator and use a 10" spring that would keep the bottom spring perch on the coilover high enough for the 255/45-17s I have on there. The difference between 255s and 275s isn't a ton. Use a sticky tire like a Potenza S03 in the 255 and you'd be far ahead of a 275 hi performance tire, as far as traction.

It's hiding elsewhere. Double layers of metal without perfect sealing is a big problem. So is the fact that the e-coat from the factory was very thin. So is the fact that there are many places water collets, including under the tar mats on the interior floors. What you are seeing is most likely fatigue enhanced rusting. The metal flexes the paint cracks, the e-coat is lost to corrosion, and the flexing opens new metal to rust. The weakened areas continue to fatigue crack and new rust develops. Vicous cycle, huh?

Agreed. Check out Pat Kelley's Dynamic CR page/tool: http://cochise.uia.net/pkelley2/DynamicCR.html

Mike, I thought for sure the LSD was only in the 87.5 through 88 300ZXT. Be careful!

TimZ, Yeah, I seem to remember hearing about using grade 5 instead of grade 8 for shear as well. Then I read Carroll Smith's books and I now use only AN or NAS bolts for REALLY critical shear bolting. I tend to use Stainless Steel elsewhere, or grade 5. I agree that the Nissan driveshaft/halfshaft bolts are great for this application as well, if they have enough unthreaded length. BTW, I used the 2.00" pilot R200 flange (couldn't find the 2.25" pilot one that the NEAPCO/SPICER flange mates to). I had a custom flange yoke made from a GM tranny slip yoke and a steel plate. The think I like about this setup is that the bolts are 10mm, not 8. I used some shim stock curled into a cylinder to take up the slack between the 10mm hole in the R200 flange and the 3/8" bolts I used (NAS 16 series). The holes in the flange yoke are right at 3/8". Miniscule slop, even when the bolts are loose.

Congrats! Got any sound clips?

Dan, sorry to hear your baby got bent, but it sound like a 6-Million Dollar Man rebuild project is in the works - "We can make it better, stronger, faster" I'll check my car and see where the X-member mount hole is relative to the firewall vertical plane. BTW, you might want to think about moving the crossmember and maybe the T/C rod bracket forward relative to the strut top mount to gain some caster.

The all aluminum big block from the factory in the 69 was the the ZL1 (427 blg block): Here's a bit of history: I stole that from: http://www.musclecarclub.com/musclecars/chevrolet-camaro/chevrolet-camaro-history-1.shtml It made way more than the 430 hp it was rated at.

Forget the Black Magic fan. The Taurus one is much better. If you have to stay aftermarket, get a big Spal fan. Also, make darn sure you have no air in the system. Before I got all the air out of the coolings system, my Z would register 20 degrees too high. After cycling the heater core valve open and closed about 20 times while cruising, and keeping the recirculating overflow bottle topped off, I got all the air out. I would be cruising down the road (had lots of time - going from DC to Atlanta a month ago ) and saw the temperature creep up to 220 or so. It seemed to do this as the car was going up and down small hills. So I began to visualize the temp sender getting uncovered as the car's pitch changed. I knew that sometimes cycling the heater valve opened and closed could move air bubbles around, so I tried it. As soon as I opened the valve (moved the dash lever from cold to hot) the temperature plummeted 20 degrees or more. Then I'd close it again (put it on cold). A short time later the gage would read high again, so I repeated the process. This went on for an hour. After shutting down for one of my many gas stops, I guess the system purged the air and sucked some coolant from the recirculating bottle. After that, it never read above 195, which is the temp of my thermostat. The moral is : if the sending unit for the gage is not in the water/coolant, it'll read higher than the water/coolant actually is.

Congrats, Perry! I love hearing startup stories! BTW, you're the only person I can ever remember doing a turbo L6 and then going to the V8. Care to elaborate on why?

No MSD box yet, John. Thanks for asking. I have one of those low resistance non-carbon center rods in the cap - came with the Brute Thunder coil.

Good point about the threaded part being in the hole. On some bolts though, the shank is a bit bigger than the outer diameter of the threaded part, so it may not be a problem. I used Aircraft Shear bolts - NAS bolts. Yeah, expensive at $3+ a piece, but big deal. They are MADE for shear loading and are stronger than grade 8 and AN bolts in shear. I got mine at Aircraft Spruce and Specialty, but McMaster Carr or any aircraft hardware supplier can get them. I used milspec nylock nuts AND red loctite.