steve91tt

The tires are 205-50-15 Nitto NT01's. They make a great, inexpensive track tire. According to the iphone, Harry's lap timer app I was running right around 1.0 g's in the corners all day long. I've used these tires for 8, 25 minute track sessions at Texas World Speedway, another 20 or so sessions at Houston MSR and about 1000 road miles. They still have some life left in them. The car itself has a stock L24 with 44 Mikuni's running on 250/300 F/R coilovers. Stock roll bar in the front and none in the back. Stock R180/4-speed. The Cayman in the video was also running coilovers on NT01's with engine mods. This was only the third run of the day so I'm pretty sure the Cayman wasn't familar with the track. Even so, it sure felt good to park it in his trunk on every lap after being blown away in the straight.

We had tonnes of fun at the Driver's Edge track event this weekend at Houston MSR. I started the day in the blue run group but was given a battlefield promotion to yellow part way through the event. I asked an instructor to take me around the track in my car during the instructor run group. He was able to pick his way through the field, passing some much newer cars. I was pleasantly surprised how my little car kept up. I just need to figure out how to drive it like he does! I got to play with a highly modified Caymen R. I kept right on him for 5 laps until he finally waved me by. I know DE events are not actually racing but it sure feels great to keep up with the much more expensive cars.

I am having electrical problems with my 1971 240z. When I turn the headlights on both signal lights start to dimly glow. The electrical system is fairly stock. I've cleaned up the contacts on both the turn switch and the headlight switch. Has anyone seen this sort of thing before?

I think I figured it out. This is my track car, I was adjusting ride height by playing with the height of the lower perch of my coilovers. I was checking ride height by measuring from the quarter panels to the ground. As it turns out, the bottom of my quarter panels are not aligned well with the suspension, side to side. In other words, setting ride height based on quarter clearance induced a pull. When I redid the height based on suspension hard points the pull went away. My bad. I ran 8 track sessions with the car this weekend and it worked great. No mechanical issues. Thanks for the help guys.

Here is a great utility for mixing and matching L6 bits... http://www.ozdat.com/ozdatonline/enginedesign/ I don't know anything about the pistons that you mention but if you keep the static compression as defined by the tool in the link above at or below 9.5ish then you should be fine with stock cam and ignition timing on 93+ octane fuel. If your static compression goes much above 10 on these engines then detonation becomes an issue without better gas or excessively retarded ignition.

Lots of things to check. Thanks for the great suggestions guys!

My 1971 240Z has developed a pull to the drivers side. It is bad enough that at highway speed the car will switch lanes in about 7 seconds if you let go of the wheel. I have checked the camber, caster and toe on the front end. Everything seems to be fine and balanced left to right. The tire pressures are all within 1psi of each other. The ride height is even side to side and the front is about 0.25" lower than the back. The car corners and brakes normally. I'm scratching my head on this one. Any suggestions?

Very impressive job. I hope that this is not the last of your excellent refurbishment posts until spring!

I use the RX7 pump on both my cars. One with Mikuni tripples a Holley regulator and no return line. The other is a booster pump on a Rebello 3.0 liter with SU's and return line. I can't hear either pump over the other noises in the car and neither as ever let me down.

Bump steer spacers are only of value if you lower the car enough that when you hit a bump in a hard corner it compresses the suspension and the wheel toes out. In a Z this is generally caused by the tie rod and control arm being at different angles. If you want to get technical the bump steer spacers don't actually change the bumpsteer they just make it less noticeable by changing the roll center of the car (some great reading over on Hybrid Z). The good news it that for a street driven car it is almost never an issue. For a track car driven at 10/10 it can be. However, I'm running illuminas and lowered coilovers on my track car without bumpsteer spacers and I have not had any issues with unpredictable steering in corners. If I ran at a lumpier track it may be more of an issue.

The best way to do it also depends on your engine hoist and how much room you have in your garage. I tried to do engine and transmission together but I could not get my hoist high enough to clear the fenders and miss the suspension while not hitting other things in my garage. I got half way out and ended up starting over. For me, removing the transmission while the engine is still in the car is the easiest way to go. A transmission jack adaptor makes pulling the trans a very quick process.

Cool! Thanks.

When I bought my 1971 240Z it came with an extra wiring harness. The previous owner told me that his mechanic told him to buy it back in the mid 80's but he never got around to installing it before he put the car away. The tag on the harness says "24012E4602". It looks to be brand new and never installed. Does anyone know if this is indeed the dash harness for 1971 and does anyone know of someone that might need such a part for their restoration?

The 15" wrench and vice grip worked great! Thanks for the nut buster suggestion John. I'll save that for the next one.

My friend has a 15" adjustable that I will try with your vice grip suggestion. Thanks for the input!

I am trying to adjust the toe on the front end of my 1971 240Z but I am having no luck loosening the jam nuts that keep the tension between the tie rod ends and the steering rack. I have tried penetrating oil and a propane torch. I can't seem to get either side to budge. I'm pretty sure the driver's side has reverse thread and passenger side is normal. Other than that is there anything I am missing that is keeping me from getting this nut loose? Here is a picture of my problem nut from the passenger side...

I'm confused about how many miles are on the car. They say the car has 22K, the rebuilt transmission has 45K and the rebuilt engine has 70k. I guess they used older rebuilt parts but it would be good to ask lots of questions.

As you point out, you've added more resistance to flow through the radiator when you went to electric fans. This can cause air to take the path of least resistance and go around the rad rather than through it at highway speeds. How does your fan support look? I noticed in your photos that the air duct on the carb side of the engine is missing. This is a great path for air to go around the rad. As a quick and easy test, you might try temporarily taping up any holes you have on the rad support and see if the problem improves. You are trying to get every little bit of air that comes in the grill to go through the rad rather than around it.

If that was taking it easy I'd like to see a video of you with your foot in it! I don't know if you have done it yet but I found that plugging up the holes on the radiator support helped me keep things cooler on the track. You basically want every bit of air that enters the grill to exit through the radiator rather than taking the path of least resistance and going around the rad. That means plugging the holes on the rad support as well as sealing the lower valance to the bottom of the rad support. This maximizes the air pressure drop through the rad and thus flow through the rad. With this small modificatio, even on a +100F track day in Texas my car runs cool. You also get the added benefit of lower drag coefficient. Lots of information in the wind tunnel section of hybrid Z on this. Sorry if this is old news to you but I thought I would add my $0.02 as I have fought the track overheat thing for a while.

Nice driving! That twin turbo didn't stand a chance.

The problem went away when I rerouted my vent line for the tank. I believe there was a low spot in the vent line that was filling with gas which made it harder for the tank to vent and thus stressed the pump (pumping against a partial vacuum and thus the carbs were starved. Just a theory but moving the vent line made the issue go away. Good luck!

I don't know much about BSFC (Brake Specific Fuel Consumption?). I did a quick google search but did not fully understand what I was reading. Is this the fuel consumption per horsepower at WOT?

Wow. I had no idea. If my flywheel nuts are bottomed out would that cause the extra long engage point I am experiencing?

I hadn't thought of that but unfortunately I don't think thats the issue as the clutch peddle and pivot look good.

The paint code is 901. Update... I replaced the master. The engage point became nicely consistent but I still had the issue of intermittent gear grinding. I replaced the clutch with a "Brute" brand (recommended by Dave Rebello as being the best value stockish clutch out there). The Brute kit came with a new clutch collar, bearing and bushing so now everything is matched and new (at least with the mechanical part of the clutch). The car shifts much better now. No more grinding into gear but the engage point is on the floor even with the upper and lower stops removed. If I adjust the clutch peddle to move the engage point off of the floor the master does not fully release and I get the inconsistent peddle again. I bench bled the master three times and still no change. I'm getting about 1" of throw at the slave as it stands. The car is drivable but the clutch peddle has a HUGE throw. Feels like driving a tractor. At this point I believe that my problem is something to do with the geometry of the flywheel. I am running an aluminium, Forenza unit. I could pull the trans again and put the stock flywheel back but I love the responsive nature of the lightweight aluminium. Any suggestions?