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Zedy....I could say the same thing about yours.....especially your engine bay....Wow! The silver car is the original paint believe it or not. Bought that one from Jeff Mader. Guy

Hope these help......

I talked with the Z Doctor in Roanoke yesterday......same question.....how much can you safely shave off of a P79 piston? He wasn't sure, but thought he remembered that you needed a minimum of .250 inches of material on a piston head to be safe. Does anyone have some type of caliper to measure the thickness of the material in a P79 piston, or can they confirm that number?

Great info......Seems like the P79 pistons actually do come out of the late block .020 inches from the factory and if you use Steve's .045 inch compressed gasket, you're running a piston to head clearance of .025 inches......that's interesting. Now if you do run into a situation where the block is milled or clearance is too tight, how much can you mill off of the P79 piston safely. Anyone know what the max material that can be removed from a stock P79 piston?

Steve......I can't remember exactly what Dave said, but I thought he told me .045 inches.....but whatever he said, it seemed like a lot to me at the time. He deals with race engines, so street engines under 7,000 rpm will probably survive less. My questions are these. 1) What is the average gasket crush thickness for the stock Nissan gasket 2) What is the minimum allowable clearance between piston and head for L series engines 3) What is the max material that can safely be removed from the stock P79 and L24 pistons. No guessers please. I'd be interested in what John Williams or Dave Rebello or someone of equal knowledge has to contribute........it's probably already been discussed on Hybrid.

Malibud.....I'm interested to hear what John Williams says is the max that can be removed from P79 (flat top pistons) safely. I've shaved as much as .025 inches from my 73 Nissan 240Z pistons which come out of the block by .030 inches by design, because they were designed for the open head late E88 head. I believe the minimum clearance between piston and head that Rebello recommends is .045 inches, which means a stock crushed gasket is .060 inches meaning your P79 piston would need to be milled .035 to get that clearance. .035 inches seems like a lot, but I'd like to know if John thinks that's OK. Also, I'd like to know what John thinks is an minimum allowable piston to head clearance is for the L series engine. Shaving the pistons is definitely the easiest solution and allows you to stay stock with your gasket. I agree with Madkaw on the front cover. Put some 220 grit on a flat surface and remove enough from the front cover to match the block.

Thanks Arnie.....Just what I was looking for.....Guy

Anyone heard of any new sources for L series lash pads.......... .150's, .160's, .170's and .180's ? Just checking on possible new suppliers.

As cheap as a disc is, why would you ever not just go with a newbie?

Dltalfa.... I installed one in my green Z while the tank was in the car. Remove the two wires from the sending unit, with a short flat head screw driver, tap off the lock ring.......remove the old unit. Coat the (new O ring with grease)so it stays put while you slide in the new unit, then tap on the new lock ring....reattach the wires. One hour job....no problem.

Offer him $500.00.......part it out and use the money you make on parts to buy a car with a less issues......."jack up the radiator cap and put another car under it" .........this car is toast! IMO

Steve's the "go to" person for electrical issues......Vanderbilt E.E. ......give him your info and he'll make it right! He's saved my azz a number of times! :ogre:

ZWolfe......Yes, if you bore.040 over, you won't have to notch the block. Notching the block is not difficult either, as long as you don't go deeper than the ring or back under the head gasket. The late E88 head is probably the worst performance choice you can make for an L series engine IMO. The early E88 and E31 heads used brass valve seats which are incompatible with unleaded gas. If you go that route, you'll need to have hardened valve seats installed. If you do go that route, you can install L28 valve seats and L28 valves and pick up a nice combo for your L24 block. If you do go with the bigger valves, you'll have to notch the cylinders for clearance of the bigger exhaust valve. If you bore .040 over, no notching is necessary.....you'll have enough clearance for the larger exhaust valve.

The bigger exhaust valve ain't going to do that much for performance. If you want performance, buy an early head, install the L28 hardened seats, L28 valves and notch the block......or better still, bore .040 over and you won't need to notch the block. The late E88 heads are just plain poor as far as performance is concerned.

You can eliminate the problem with a simple notching of the block (for the exhaust valve).....a better solution is to get an early E88 or E31 head.....they aren't that hard to find and will give you a better performing engine (higher CR). IMO

Woody Staub's Executive Z built by Greg Ira. Beautiful car.....great color combination.

Olzed is right......your auto Z has a 3.54 diff. A 4 speed will be turning 3,000 rpm at 60 mph with that diff......not fun on a long trip. If you have a late 71 Z with the long driveshaft, there's no difference between installing the 5 speed versus the 4 speed.....both transmissions are exactly the same dimensions.The 5 speed will work much better with the 3.54 diff. If you have an early 71, it could require some mods. If you have a late 71, the 5 speed is a better mousetrap IMO.

The only differences that you'll be able to see (to confirm the update has been done) is the rear control arm hanger is curved (behind the diff) as opposed to the early cars (straight) and if you look close you can tell the mustache bar is flipped 180 degrees. This gives the diff the space to move back when the new diff mount (which moves the diff back) is installed. Great project! PJOE (Brian) can help you with altering your shift lever to clear the console.

Bill.....Doesn't matter whether it is an "A" 4 speed, "B" 4 speed or 280Z or 280ZX 4 or 5 speed tranny (they are all the same dimensions).......If you have a series I that doesn't have the updated conversion (series 2 diff hanger, flipped mustache bar and late diff mount and longer driveshaft) you have to use the short driveshaft. If you add those four items, you'll move the diff back so the half shafts aren't angular.That's why the factory changed that on series II cars....it got rid of the vibration from the half shafts angling forward on the early cars.

I like cork gaskets.....they seal real well with no leaks. I don't use any sealant. The crush of the thick cork gasket compensates for the distortion of the oil pan. Don't torque it too tight though.

Blue ......4 piston Willwoods (no idea what diameter...Arizona Z could tell you). Mitchell...yes I used the stock Datsun M/C and booster....it works perfect. I know people recommend the 15/16 M/C, but stock works great for me.

Mitchell.....Just on the 72 with front and rear Willwoods. I think most of your stopping is done with the front brakes.....If I were you Mitch I'd just go with fronts......see how you like 'em......Heck of a lot easier than the rears. The Willwoods are really nice looking and they work good, but I rebuilt the stock fronts on the 73 and replaced the rotors and they work pretty good too.

Blue....All but one of my Z's run Willwoods with vented rotors on the front. The green 72 runs Willwoods front and rear. I use the stock M/C on all 5.......works perfect. Regards. Guy

If it stops, but feels like you've got to stand on the pedal to lock it up, you've dropped the reaction disc in the booster. Take off the two nuts that hold the MC to the booster and pull it back a couple inches (no need to remove the brake lines ). Pull out the plunger from the booster.......neck down a vacuum hose to a small tube and suck the disc out of the booster. Super glue the disc to the back of the plunger and reinstall......night and day difference.

Did you remove the master cylinder for any reason?