DHale_510

Very true. I even broke a rear trailing arm pivot bolt. Basic problems with these conversions include a small oil pan opening between the steering and firewall, small radiator opening, double the hp needs double the airflow through the radiator, small exhaust provisions and minimum height for intakes. Putting a pretty 510 hat on a fancy tube frame chassis may be the fastest, easiest and cheapest solution. OK nothing is cheap here. The 215 additionally has a rather unfortunate alloy, easy to cast but begins plasticity at upper coolant temps so a fancy crank girdle to resist heat soak. Heat soak keeps it from turning over between autocross runs of 2 minutes for example, so now we really need to do a very extensive build eliminating the weak rods and valve train and the Muncie M22 gearbox fits the rare manual bell housing but the little automatic is totally wrong and on and on. But it does turn 7000 rpm easily and sounds so wonderful...... Dennis

Buick 215 in a 510. Sure its been done. Really expensive and impractical though. Mid engine with 300hp, 10" slicks, 2000# and great on paper. Lots of fun but unpredictable behavior, except it will break something at all times. Cutting the firewall out meant a full race chassis inside, a ship in a bottle if you will. It remains a magnificent garage ornament. Dennis

Several problems to address: I think that the lower mount is not strong enough for a coil over mount, it's too small, and single shear is also not enough. My autocross car loosened the mount every day. The ride height to toe out problem means you need to realign the car for every change in ride height too. Not easy. The wheel rate will be about 10% higher than the spring rate for the same reasons the stock position reduces the spring rate to wheel rate. Dennis

The longer travel is easier to modulate but it feels best on a second pump. Not easy to recommend this to someone I don't know. I also relocated the hole in the pedal lower, the original hole was worn anyway. The stock 240Z master was 11/16, right in the middle and is worth the effort to make work without the booster. The big ZX ones always want the booster that is usually too big in a 510. There were some small boosters on 10s and maybe some pickups that I have used with SUs but not Mikunis.

I rode with Matt around Sears Point for about twenty minutes one time. Seemed like 6000 rpm and 90mph the whole time. I felt no lifting and no fear then either. No overhead planes to worry about there .... Dennis

Lash pads need to be sized to the valve seated height. "Stock" lash pads are usually too thin after a "rebuild". Also "rebuilding" a Datsun head with a pair of stones like a Chevy will make them all different and wrong. The cam needs to run on center of the rocker wear pad. The adjustment screws are long for rocker removal, about twice the range for centering the wear zone. Again, not a Chevy. Worst case the Stellite wear pad is off the edge and is turning into a little lathe tool and cutting into the cam. I suppose that would seem noisy... A good Datsun rebuild of a cylinder head is done with a cutting tool [Neway branded] on a mill table all set up true and parallel and equal depth. It takes tooling and time and costs more. Dennis

The little plate was for reinforcing the flex plate on automatic transmission cars. It also is good to use with an aluminum flywheel to keep the bolts from digging into the aluminum. It goes between the bolts and the flex plate or flywheel, not under. The raised part indexes into the flexplate but would not fit under a flywheel well. It seems to have been jammed into the seal here, likely a big part of the leak and goop fix... Dennis

It's usually a loose half shaft u-joint first. The diffs seldom knock, but they are all old parts now. You can usually just wiggle a loose half shaft joint to check. It ought not wiggle. Dennis

The little white Koni knob in the picture is the adjuster. Easy to use up front, not so much in the back. I found that some early Z struts were skinnier than later ones and maybe that's a problem with ZX struts, I dunno. Since ZX struts are about the same length as early 510 struts maybe you could back convert and just play with hydraulic oil viscosities as we used to do before we could get fancy Konis and such. Dennis

Just as important as the nylok nut is the d hole washer on the pivot side. Dennis

Also remember that every change in rear ride height you will change both toe and camber. Both will make major handling changes without and visual change. Most of those changes are pretty dangerous or tricky. Lots of 510s with smashed rear ends from this. Once mastered though that trailing throttle oversteer is great fun. That's largely why 510s are great autocrossers. The look is the least thing you are chasing. When we first put coilovers on the back of the Pink car the lower mount bolt would loosen every day. We were hillclimbing, maybe 15 minutes a day hard use. This was with spherical bushings too. I ended up reengineering the whole system to use grade 8 through bolts in double shear. They never loosened again, but beware and pay careful attention, there's a lot more stress there than you imagine...... Dennis

If you seal off the drains then the water will come in through the heater. Not better. Dennis

As far as a choke, there really isn't one. The mechanism drops the jet and makes a richer mixture. The SU slides are always a choke. On my ITS spec 240Z I just use a piece of copper electrical. #14 solid, and pull it up, hook it onto the heat shield until warm, then release it and go hammer the old girl for an hour or so. The wire has lasted about 20 years now.... Dennis

Well, sure but.... I have spent many hours on dynos to try and reengineer distributors and ignitions, "Tune them" as Matt calls it. The CB piece looks great, I had Brian Rebello do this sort of thing with a Microsquirt controller some time back on a sweet L20b with Fuel injection and electronic ignition, but it is a costly process. It cost as much as the built engine did. I talked to Electromotive at SEMA a few years ago about my fancy 2 liter Cosworth Ford and they started at about $10K to "tune" it. It is a museum piece now I guess. Peggy calls them rabbit holes. I just get a little enthusiastic when I do things I guess, but without the "tuning" equipment it is kind of a disappointment. Like Matt says, if simple works, do it. Those round holes on the front of the carbs are the things that actually allows the slides to rise and function more or less like throttle plates so you need them open for sure. Dennis

Check for oil in the tops. They use the oil up and will run rich when low. Add oil each oil change. Try to leave the balance alone. More often than not imbalance is from valves needing adjustment. Vacuum advance plates in the distributor will wear quickly. Manifold vacuum is much less than venturi vacuum and will not work well, but then again it may be the same as no vacuum at all. Unfortunately as the advance plates wear, the advance may stick somewhere and totally mess up the advance curve function. I find a carefully set and fresh vacuum advance is only worth about 10% fuel economy and not much worth the effort. Idle advance is much less important than the advance at torque peak and full advance. Ping setting is trouble, first ping happens at torque peak and that will not be audible. Cam changes alter all of this. Larger displacement does too. There is a big difference with 2200ccs instead of 1600cc. Big bores burn slower, high compressions burn faster, big cams fill the chambers slower, and so on. Like Matt says, recurve the distributor for the newly reengineered package. Free advice on the internet isn't of value here. Maybe mine too. "Lumpy" cams are trouble with SU carbs. They are CV designs that work with manifold vacuum more than throttle position. Reduce the manifold vacuum and they will not open as soon, just the opposite of what the cam is trying to get. Leaving the oil out is a poor work around on street cars. It works OK on an IT spec racer but all you want is WFO there. Where angels fear to tread...... 1000rpm idle speed with "lumpy" cams are about right. Stock is about 800rpm. Datsun Roadster choke cables were the original part, they may still be available. Pretty close to MGB parts. 240Z parts can be used if you want the lever by the shift lever. These motors like to run warm, 170 is usually too cool. 38mm carbs on a cammed 2200 seems small, but I have not been happy with 42mm Z carbs there either.... Dennis