z-ya

You might be right, but I think the cage is going through the panel that separates the cowel drain area and the passenger compartment, and then stops at the firewall at a plate. Then in the engine compartment a separate section that ties the firewall to the strut towers. It's hart to tell for sure. I know who to ask who would know for sure. Anyway, this was built to mid 70's IMSA rules. Note that this was a new "salt damaged" 260Z that they started with. Bob Sharp convinced Datsun back int the day to sell all salt damaged cars (ones that got damaged by sea water in transit) to racers for $100. The stipulation was that they could only sell it to another racer, or destroy it when they were done. All of the Z31s that Tom Cruise drove (and wrecked) were salt damaged cars. When we gave the Nissan dealer the VIN for this car, they said that this car was destroyed at the factory.

I don't think it actually passes through the firewall. The tubing is welded to the firewall on both sides via a plate.

Though some of you would appreciate these photos. These photos were taken while this car was being fabricated at the Bob Sharp race shop in the mid 70's: Notice that just about every seam is welded, probably using gas. Beautiful work. http://s160.photobucket.com/albums/t177/psanders240/BSR-260Z-IMSA/

Stock N47 head (no porting), .460 lift / 280 deg duration cam, stock springs and valves, cast flat tops: Solid line is dual TB SU manifold. Dotted is stock EFI manifold. 180WHP is easy, streetable, and reliable.

Couldn't be said any better.

I think mine is a 15/16...

Is the ignition coil stock? Does it have the balast resistor installed. I have attached EE and EF sections from the 76' manual. Follow the diagnostic steps in these sections. EE.pdf EF.pdf

I'm running a hefty cam in my 13:1 L28 race motor (580+ lift, 280+ duration), with 50mm Mikunis (opened up 44mm with chokes removed), and 11lb flywheel, and I'm surprised that it is actually somewhat drivable on the street (took a little rip up the street the other day). It doesn't idle well below 1200RPM, and doesn't have much power below 3000RPM, but above 4000RPM, it pulls like hell. I recently picked up an L24 that has never been run, has Arias forged pistons, and supposedly was build as a "race" motor with a "3/4" cam. What the hell does a 3/4 cam mean anyway? 3/4 full race? What is full race? It has an E88 with polished chambers. Ports look stock. I'll post picks when I pick it up. I plan on just going through it and then seeing what it can do on the engine dyno.

Duh, yea, your probably right. You would have to re-torque the head. If you don't want to run the spray bar with the internally oiled cam, MSA sells little block off plates, or you can make your own. But again, it doesn't hurt to use the spray bar. I would suggest converting to solid lifters so you can set the lash correctly, and then confirm the wipe pattern is correct. Get this wrong, and your cam will be junk in a matter of seconds. Also, after breaking in my race motor with it, I suggest using the RedLine break in lube for a new cam. It has a very high ZDDP content, and will ensure that the cam breaks in correctly. That is about what my NA 460 lift cam did, so it should be similar in a turbo application.

Why do you think you need to remove the head to swap cam towers? You can run the new cam (internally oiled?), with a spray bar (I do on my race engine). Are you switching to solid lifter at the same time? I'm not sure how to check the rocker wipe pattern on a hydraulic P90A. I would think that you would need oil pressure to pump up the lifters to get an accurate wipe pattern.

Don't just slap it in there and see what happens. What is the cam lift? What about springs, lash pads etc.? Check all that stuff before putting it in to find out that the springs are weak, and the lash pads are wrong. Then you'll be takin' the head off for sure.

I stand corrected. It makes sense to use a PCV in any boosted application as a check valve to prevent over presurizing the crankcase.

Looks a lot like a Megasquirt relay unit. I personally don't like the screw terminals. Any modified harness should be crimped and soldered for reliability.

Now that is a pile of garbage..... First get the car to run and drive reliably, then worry about longevity. Now as far as the lack of a PCV effecting performance, I've never run one on a race car, and never had problems with performance or crankcase ventilation. PCV is mainly for emissions.

Or, just plug it and not run a PCV.

Joe, Got any pics? This is exactly what I was thinking. Reinforce the rockers and possibly the floor frame rails to minimize the twist in the middle that a stock S30 has. No cage, or roll bar (I'm not all that keen on driving a car with cage without a helmet). Keep it looking stock inside. Maximizing seat travel and interior space while making the chassis a lot more rigid. Front and rear strut tower bracing has been well documented. I'm looking at way to stiffen the middle of the car. Thanks, Pete

I too am interested in how to strengthen the middle of the S30. Stiffening the front and rear sections are pretty straight forward. A street application. No interference with seat or door panels. Just make the chassis stiffer without it looking like a complete cage.

My L28 240Z setup for vintage racing:

Spacers?

Nice cage Mike.

I really like your setup, and those are decent numbers at the wheels. I am assuming that the carbs you are using are motorcycle, correct? Who made the intake manifold, and do you have a thread here on hybrid showing how? Are the pistons flat top? Did they cut the head to get the higher CR? Thanks, Pete

The turbo sounds like mine. It's got that Chris Craft blurble to it (at idle).

Ken, I had the same problem on my RB swap. It was the driveshaft balance. With the RT bracket and poly differential mount (which I also have), it is extremely important to have a very precise balance on the driveshaft. Most driveshaft shops balance good enough for a floating solid axle application, but not good enough where the differential is solid mounted to the body (especially with a poly mount). Gilbert's in Manchester NH made my driveshaft, and did their normal balance. It vibrated at 55MPH like your car. It would smooth out over 70MPH. So I brought it back and they did a more precise balance (they call it their race balance), and it fixed the problem. Pete

Did you check that you have fuel pressure and fuel flow?

It just can't be triggered from the crank, and specifically say distributor. It doesn't say which distributor...