steve91tt

John, Is the back of the firewall tied into the knee bar of the cage on the other side of the strut bars in your photo above?

I run a stock "Brute" brand from rockauto in both my track car and my street car. It comes with a new clutch collar, bearing and bushing all for about $100. My 1971 car has a Rebello L30 with over 2000 hard track miles on it with no sign of slippage. As Wade said above, unless you are drag racing its hard to beat a stock clutch for these cars.

No one better with Datsun suspension. Congrats John.

Great thread. Keep the pictures coming!

I can say that in my case going from 34mm to 37mm was nothing but positive. More power up top and no noticeable difference on the bottom end. I wish I had gone with 39 or 40's.

I have run the 1979-1981 RX7 pump in both my track and street car. I'm using a little different style pump than the one shown above. Great little pumps, quiet and so far very reliable. However, I ended up recently changing to the Carter in my track car as I found that I could out run the pump at WOT in 4th near red line at the end of a long straight. It wasn't a problem until I switched from 34mm to 37mm chokes in my Mikuni's. I don't see this being an issue for a street car and I will continue to run the RX7 pump on the street. I thought I would share my experience for those who run on the track. If you see your AFR's drop off at high RPM's then you might look at installing a fuel pressure gauge in the cockpit. Just sayin'

I've 15000 miles of daily driving in my stock 240Z for a couple of years now. I agree with the posts above. If the car is in great shape it can brake handle and accelerate like a modern car. Safety is an issue however. I'd stay away from a roll cage in a street car. There is not a lot of head room in these cars. Keeping the bars far enough away from your head so that you would not need a helmet to drive it could be an issue. If you get in an accident your head is going to move around quite a bit. If it hits the roll cage very bad things can happen. Google "driving a caged car without a helmet". You might be surprised what you find.

Yes, sorry, no more low AFR's as long as I keep my foot out of it below 4800RPM.

I spoke to Dave before I headed to the track this weekend. He said that an AFR up to 13.5 is acceptable for my engine combination. He also said that with my cam (mild Rebello race cam) he has never been able to tune out the rich condition at mid RPM's that I describe above without going to fuel injection. He told me to simply gear down, let the engine rev and never load the engine below 4800RPM. He said the engine will run at 7200rpm without issue so simply keep the RPMs up. I followed his suggestion, dropped to 2nd in the slow corners and ran the car to 7000RPM with each shift. This resulted in more torque coming out of the corners and the ability to rotate the car with throttle when needed. I guess I was driving it like a V8 in the past rather than letting it rev like it was built to do. Problem solved.

Thanks for the link Blue! I will talk to Rebello about the safe AFR for my engine at WOT. If he confirms that low 13's are ok then I'll give that a try at the track.

Thanks for the heads up on the flooding on hard right turns thing. I'm on the track this weekend so I will check out the AFR's in the right handers and report back. If I go to WOT at 5000RPM in 3rd rather than 3500RPM I don't have nearly as bad a richness issue. I've been working with Todd at Wolfe Creek with the jetting over the past couple of months. We started by switching from 34mm to 37mm chokes. My starting jets were the following... 34mm venturi 150 fuel 200 air 40 pump 55 pilot As you can see we moved up two steps on the fuels and down two steps on the pilots. I think the pilots helped a little as the AFR's used to drop into the 9's and now they stay mostly in the 10's on acceleration in 3rd. I also have a set of 230 air jets that I tried. The air jets seemed to help with the mid RPM richness but the AFR at redline in 4th moved into the low 13's. This seemed a little lean so I went back to the 200's. How lean is too lean at redline? Would a combination of the 230 air's and bigger mains be the next place to look?

I'm running a set of 44mm Mikuni's on my Rebello L30 in my 240Z track car. The car runs great at WOT and never stumbles regardless of throttle transition. I'm 95% happy with my current setup but the engineer in me wants to get that last 5%. The problem I am having is that the car runs very rich on 3000rpm, 3rd gear corner exits. It does not stumble but it feels like its drowning in fuel. AFR's are as follows... 4th gear cruise = 13.0 idle = 12.0 WOT 4th gear at 6500rpm = 12.8 3rd gear roll on from 3000rpm = 10ish The carbs are currently jetted as follows... 37mm venturi 160 fuel 200 air 40 pump 50 pilot When I roll the throttle on in 3rd it stays rich for quite some time before it slowly leans out towards redline. I've tried playing with both the pump rod length and the pump jet to no avail. It seems that if I lean the things out too much with the accelerator system I develop a transition stumble. Is this something that can be tuned out of these carbs or do I just have to live with dropping to 2nd gear on corner exit?

Coop, I have one of those Wink mirrors as well. Mine is mounted much higher on the windshield than yours. I haven't decided on whether to keep it or not so I'm also interested on what you think of yours and how you keep it from vibrating with the mounting arms being so long. Outstanding driving by the way!

When I changed the master cylinder I also added rear disks and a proportioning valve to the rear line directly after the master cylinder to balance the system. This required some minor plumbing changes. If you are just swapping master cylinders I don't think much if any new plumbing would be required.

Very nice driving!

I bought 535245 and it fit nicely with no modification. YMMV. I don't know if the bigger one will fit.

I'm running the wilwood system on my 1971. Yes, the 1973 is bigger.

The stock booster is working great for me. Rock auto seems to still sell them.

I've been very happy with the Wilwood 1" master on a stock booster with Wilwood brakes. http://www.wilwood.com/MasterCylinders/MasterCylinderProd.aspx?itemno=260-8794 I was running the 15/16" until it failed. I couldn't find a rebuild kit for it so I switched to the Wilwood master. It requires a small amount of filing on the base of the master to get it to fit but once installed you can't see the modification and it looks very close to stock. Here is a thread on hybrid Z about it... http://forums.hybridz.org/index.php/topic/102754-a-one-inch-diameter-brake-master-cylinder-for-the-s30-z-cars/

Welcome fellow Texan.

Silly question...is the rotor turning? I had issues with getting my Mallory to couple to my oil pump drive when I first installed it.

I believe the F1 guys only have to keep one tire inside the white lines (although the marshals don't seem to catch all of the violations). Whether you are driving an F1 or a Datsun, in some corners it's faster to clip the apex and/or track out wide. All else being equal, the guy who never drops a wheel will be slower than the guy who runs consistently with two wheels on the curbing. Since the rules allow it, pro drivers have to ride the curbing in order to continue to be pro drivers.

Do you have a wide band to go with that MAP sensor dealy-bob.

As I understand it, the pilot screws adjust the amount of fuel that is added at idle. The pilot jet meters the amount of fuel for idle+progression ports (the progression ports are the little holes that are uncovered directly after throttle tip in. Ideally, these should be covered at idle). Therefore, adjusting the pilot screws changes the air to fuel ratio at idle. However if you adjust the position of the butterfly with the idle adjustment screw enough that you uncover the progression ports then you will start to meter fuel through them and this can cause a rich condition. If you don't have your carbs balanced at idle you can have progression ports on some cylinders open at idle and some closed.

I have been running Mikuni's on a 1971 240Z for the past year or so. Once I got them tuned they have stayed tuned. They fire right up and run smoothly every time. The only issue I have is a fuel smell in my garage if I shut the car down hot without opening the hood. I like triples enough that I'm in the process of refurbishing an old set of Webbers for my 1973 240Z. SU's are great. Very reliable and simple. Triples can be just as reliable but not as simple...just more fun.