JMortensen

You know we had a guy from NZ the other day say that they can get ARB lockers for the R200. This would be THE KICK ASS DIFF for drag racers, in my opinion. You drive to the track with an open diff. Push a button and its a spool. Do your runs completely locked, then push the button again and drive home. These things are VERY popular with the rock crawling crowd, so I'm sure they'd handle a high hp drag launch. I'd love to see one of you guys try it. I'm guessing it might even be cheaper than a Quaife, you'd probably have to have one ordered from Oz if they're not stocked anywhere in the US.

There is something known as pad "knockback" which is described in detail here: http://www.stoptech.com/tech_info/wp_knockback.shtml but to be honest I've never heard of anyone complain about it on a street car.

I think it is possible to do most of the expensive stuff at home. The work that I had done at the machinist was: 1. Hone the block 2. Balance the bottom end. 3. Valve job. 4. Install 280 valves in the E31 and port the bowls to match. That was it. The rest I did myself. You might not get all 10/10ths of the potential power out of the head, but you can easily get 8/10ths, and maybe more if you take your time with what you're doing. The engine I built in my garage is a 2.8, I had larger valves installed in the E31 and the machinist smoothed out the bowls when they installed the larger seats. I did all the rest of the headwork, unshrouding the valves, cc'ing the chambers, mildly reshaping and polishing the chambers. I did a little work on the short side radius and cleaned up the casting marks in the ports, but the ports are basically stock diameter. I also port matched my Cannon manifold to the head and tuned my Mikunis with a narrowband O2 sensor. I did some work to the block polishing and notching it so that the unshrouded area of the head matched the block, giving a nice area for flow around the cylinder wall side of the valve at higher lifts. I chose a cam that is really too small at .490/280. This engine makes about 240whp. I didn't bother with a flowbench although I did find DIY plans to make your own, that was just too much work for me to justify. It is also necessary to keep in mind that Dennis is talking bhp when he says 350 hp, and most people will put hp in terms of whp around here. So if you take my 240whp for example and add 15% for drivetrain losses (I know that's not accurate, might be high or low, but this is just an estimate) you get 276hp, and then size the engine up to 3.2 (+12.5%) you get 310.5 hp. Maybe not the whole 350 that Dennis got, but I spent about $2500 total and got roughly 88.7% of the power per liter that he did. Just out of curiosity Dennis, how much power do you think Larry Butler's L18 is making? I know it's not making what Pinky makes, but he ported his own head and built his own bottom end too, and it's not slow. I think Cary built his motor too. DIY doesn't necessarily mean crap. On the other hand, we had a member zredbaron, who built a stroker and put down 157whp: http://forums.hybridz.org/showthread.php?p=458664 and then he had Sunbelt build him a head with all the cool stuff for $3K and he put down 197whp afterwards. My impression of his problem is that his 40mm carbs are holding that motor back, maybe his flowmaster muffler too, but those are just guesses really. His example does prove that you can have a VERY nice head and crankfire ignition and and still not make power if the induction is not optimal. There is no magic bullet, other than sending an engine to Rebello or Sunbelt with a blank check and asking them to make it the most powerful engine on the block. Dennis can do that but most of us can't. That doesn't mean that we have to suffer with no hp though. You just have to be creative and willing to put some man hours and elbow grease into it.

So long as you can still get the grease seal in and out and it doesn't rub anything I think you're good to go.

I don't think that part of the hub is that tough. I've seen enough of them bent that I'm pretty sure of it. You could grind it out, but then you'd really have to clean the crap out of the hub because you don't want metal shavings in there.

That's what I thought you meant. That area where the grease seal gets inserted is fairly thin. I don't know about filing it down, don't think I'd want to be filing right next to the bearings, but I wouldn't hesitate to bend it back the other way with a ball peen hammer.

Once again, very nice work. It might not be SCCA legal, but I wouldn't hesitate to drive 10/10ths with that cage in a Z.

I agree with Richard here that "near zero" droop might not be such a bad thing, and I think that is what Cary has always talked about. If you look at any "real" racecar, they just don't have 5 or 6 inches of droop like a lowered Z does. Why you need all that droop is beyond me, especially with really stiff springs, and I think that Cary is right that all it really does is let the car roll further in turns than it would otherwise. He can speak for himself, but that's the way I've always read his posts. I suspect that having a bunch of aero downforce like the open wheeler might make zero droop a more attractive prospect because you'd have some functional droop at speed that way.

Welcome back Afshin! I remember we PM'd fairly soon after your accident and then I hadn't seen any posts from you since that time. I'm glad to hear the recovery was complete. Congrats on the article too. I guess that is a little belated, but I never had a subscription to that magazine. They really did the car justice.

I believe the STi has the clutch LSD R180 and the WRX has the R160. This is something of a thread jack so whoever wants to pursue the R180 thing ought to start a new thread, but the R180 has a different output spline count on the side gears, so the Z CV's don't plug in. John Coffey has tried this if I remember correctly, so he could probably help fill in the blanks for anyone interested.

This is a drivetrain related post. Moving...

Good point Pop. I changed the title to reflect what is actually in the thread. By the way bodie, I think that is Hybrid Z Rule #3; make the title easy to understand so that the post doesn't have to be opened to know what is inside. Makes it easier for the next guy searching through the database.

You can just run a short stack inside the filter you already have as well. Either way works. You have a longer manifold with the Cannon, so you could probably get away with a short stack and have a total runner length about the same as a Mikuni manifold with a longer stack. From what I've read over the years, the sock type filters are really restrictive. Can't say that the Ramflo looks much better to be honest. I'm also running the ITG, and I think it is a really good one to use, with free flow and the air can hit the stack from almost any angle.

I have driven a Z with 185s in the front and 205s in the rear, but that car was a hodgepodge of different parts and more than anything else what I remember from driving it was the ultra loud dual exhaust. So I really don't have much experience with a staggered setup, but with my years of experience trying to get my car to turn I can say that I have never thought of it as a good option for my own car. I never got rid of the understeer in my car when I was autoxing and until I do I won't go with a wider rear tire than front tire. I think that eventually I will get to that point so that's not to say that I think it's never a good idea. I figure probably after a V8 conversion I'll need more meat in the back. As it is when I started work on the car there was one turn on one racetrack that required some tact with the gas pedal. On every other turn on every other track I could apex and floor it. By the way according to math that is .8" wider, not 1.25" wider. I know that the tires vary by manufacturer, but 1.25 really doesn't make sense mathematically, it's 20mm wider.

Search and you'll find lots of info. Search "MN47" and read all the turbo stickies in the Turbo/Supercharger forum and FAQs related to the subject of turbos as well. Once you have all of that under your belt you'll be back asking some more detailed questions. I'll say this right off the bat; the MN47 head has a very small combustion chamber. If I were building a turbo motor I'd want a larger chamber so that I could up the boost more without detonating on pump gas. I'd shoot for a compression ratio around 8:1 or so. That's my take, but there is a debate to be had there and if you read you'll get all the angles on that topic as well as many others (fuel pump, injector size, turbo size, intercooler and plumbing, fuel management, etc etc).

Looks good to me! Nice work.

Done.

Maybe so. When I hear "stagger" I think of tire stagger, which I think is what John was doing too. While this wasn't addressed to me, the answer is definitely yes. It's hard to convince some people to run a larger tire in front than rear, but there is no real reason not to and sometimes like in a stock class where you can't change wheel sizes you can run a slightly fatter tire up front to change the balance. In the local autox I used to attend there used to be a lot of VW's and Fiestas in E Prepared running 8" slicks up front and 6" slicks in back.

A friend of mine had a Thule rack on her 240Z. It attached to the drip rails with no problems, but she had to cut the aluminum tracks down because they stuck out too far behind the hatch and wouldn't allow it to open all the way.

Tire stagger in racing terms is the diameter of the tire. In fact you'll find that some teams will measure all of their tires and find one that is taller and stick it on the outside front in circle track racing, or even sometimes in road racing if all the important turns are lefts or rights. http://www.circletrack.com/techarticles/managing_front_rear_stagger/ In layman's terms I've heard of the skinnier wheels in front and wider in back also referred to as stagger.

There was a very similar video or two (same track I think) with a bunch of old Japanese cars. I remember one in particular had the OS Giken head, was NA, and ran pretty damn fast. Bunch of older RX7's and lots of Toyotas too. This was probably a couple years ago, but if you're interested you might dig around on the net and find them.

This came up a couple years ago, there was a part that you could buy that extended the tie rods so that you could get more steer angle out of the rack. The issue with the Z is that there isn't room in the wheel wells for more steer angle. Z's with wider tires commonly rub on the frame rail in the front or on the TC rod in the back or both. Plus I think I remember that the spacer deals really affected the bumpsteer, which is also not ideal in a stock Z. I'd just run a buttload of toe out when you're drifting (but not on the street) and worry about other things.

One of the posts grumpy linked to did specifically use the TBI with the carb manifold and also found more power. I don't know that there has been a back to back comparison with the TBI vs the carb, but yes to answer your question that can be done and it does seem to make more power than the TPI, but one could still argue whether it is the manifold or the atomization, because I think both the TBI and the carb share those attributes...

3.90 gears are pretty common in 280ZX's. I'd find another diff with those gears, as setting those gears up in another housing will be a lot more difficult. That failure is discussed in my diff FAQ post, it is also fairly common, especially with drag raced R200s. Welding is going to make it about as strong as you can get, an LSD would help too. More info on other options, LSDs, etc in that diff FAQ post here: http://forums.hybridz.org/showthread.php?t=116207

Nothing should grind when the hub is installed. The inside of the hub where the grease seal goes is fairly thin metal and I think it would be pretty easy to distort it until it rubbed on the strut. I would guess that this is what is happening. You might put a dial indicator on the rotor just to make sure the hub isn't bent, and if it isn't then pull it back off and tweak the inside so that it doesn't rub.