Diseazd

As I understand it you can have the flat top of the piston out of the block by .015 with the stock gasket which crushes to .050 inches. The clearance needs to be .035 inch minimum. I believe that the gasket that MSA sells is for a bored out L28 and is 2mm. If anyone knows where I can get a 2mm gasket for a .040 over L24 I sure would appreciate your help. 2mm would be .080 less .035 out of the block would be .045 clearance. Thanks Guy P.S. It's a P30 block

You're right about that! The number on the crank is E3141. I pulled a piston.....both rod and piston were L24 (long rods). I'll pull all pistons and dump this block in the garbage!!! It's beautiful with it's new paint and brass freeze plugs. What a shame! Guy

Which means that the engine block must have been decked before......but .035 of an inch? .......WOW!

That'll help. The reason I ask, is because I'm building an L24 (72). I bought the motor used, so I don't know the history. I put the bottom end together assuming all was original ( it didn't look like it had ever been apart) and when I installed the .040 over 240Z Nissan pistons, they came out of the deck by .035 inches. The machine shop decked the block .008 of an inch and assures me no more, but the piston is out .035 of an inch. I pulled a rod and they are 240Z rods. Is it possible someone had installed (by mistake) an L26-L28 crank?

If you have an L series crankshaft by itself, how do you determine whether it is an L26...L28 or an L24 without measuring the stroke? In other words, are there any marks or numbers to simplify the process?

You don't need it......just use 2 metric wrenches!

Absolutely beautiful!!!!!.....Put some original seat covers along with the steering wheel IMO.

I remember slobbering over those body parts.....Called the guy, but he wouldn't sell separately. I think he shipped it overseas, and if I remember correctly, he wanted $5,000.00.

ZLADY......We're proud of you!!!! Guy

It costs me more in time and gas to drive to the dealer than shipping. :stupid:

MSA has them.

Undoubtably the best bang for the buck that you can install in your Datsun! This thing really does what's it supposed to. The bump stop is the way to go as far as simplicity. Use both the original and the bump stop for best results (damps the unit). Dave ......your product as usual is superb! Guy

Maybe Bruce "screwed up"!

Looking forward to seeing your car Ron ...........I'm sure John Morton will enjoy it too. I was sitting on the back Esses at Road Atlanta when he won the Road Race of Champions back in the 70's!

Got my dinner tix too.....Anyone up for a drink of alchohol? Guy

Thanks for that John......Carlos at Citizens Machine (Highland Springs,Va. ) is the man with Z heads......35 years as a machinist. He owns the shop and does a couple SCCA racers. He'll do a beautiful job for you! PM me and let me know what you're thinking about as far as mods. His number is 804-737-9211. He's a little hard to understand on the phone, but a master machinist! Guy

They just keep coming out of the woodwork.....don't they?

Thanks Arne....much appreciated!

I've got tranny fluid leaking from the area where the front of the driveshaft slides into the rear of the tranny. Anyone have a solution to this problem or know of any previous posts dealing with this? I assume it's probably a seal of some sort. Thanks Guy

Update on my installation of Dave's RT mount into my 70 240z: I changed all the stuff in the back to bring her up to current specs. New 72 driveshaft ,mustache bar, hangers 72 diff mount and went ahead and decided to install the RT mount. I was using the bump stop so Rich(MOTORMAN7) and I were doing the same thing but with different methods. I could see that if I installed the mount as advertised that the bump stop would be rubbing against the moving yoke on the front of the diff.....It wasn't going to be far enough back to contact the top of the front of the diff where it is supposed to hit. I flipped the mount around and drilled a hole symmetrically on the other side but even a little farther toward what is now the back of the reversed bracket to get all the rearward movement I could get (the bump stop actually had the edge hanging off about 3/8 of an inch). No problem......I cut off the 3/4 inch that Arne suggested....bolted the awesome bracket up and when everything went together it worked beautiful (I also used the new stock 72 diff mount for double duty). The car drives like a dream.....no noise no bumps and no vibration with one exception. When I nailed the little monster for all she's worth I got a vibration-grinding noise under my butt.....only when you really nail it though. I brought her back and took a look. Here's the problem...when you reverse the bracket in the early cars the little support metal bar on the bracket now lays 3/8's of an inch above that little spinning yoke on the front of the diff.....So...when you really nail it as I tend to do from time to time, you squeeze the bump stop enough to make slight contact with the spinning metal yoke. I'm going to try to drop the drive shaft and Dremel out the area above the yoke. So if anyone is doing this mount in an early car I would suggest grinding an area out for clearance. Rich...you can take a look at yours and see if that support rail is directly above your yoke. Great job on the mount though Dave....You are the man! Guy

How about putting an E31 head on that combo with L28 valves......a short stroke fun machine!

Sorry,sorry,sorry......You're right it's the rod that is different not the the pin height. The rod on the L28 is 130.2 mm vs. 133.0mm on the L24. Could you indeed build this combo of an L24 crank and rods in an L28 with L28 pistons?

H.P. is built in the head......You can take the P90 head to someone who knows Datsun heads. Shave the head .090, shim the towers and valve springs up .080 , install early longer L28 valves (they are .080 longer) and you will have approximately 10 to 1 C/R. Next, choose your camshaft (going stock is cheaper) but performance is more H.P. If you have a cam reground, you'll have to install the proper springs and lash pads to attain proper valve train geometry. The stock L28 cam will give you 10 degrees more duration than the L24 cam and more lift....plus it's a lot easier than going with the springs, lash pad and retainer route. You should get a nice boost in H.P. by just shaving the head and running the stock L28 camshaft. Remember....you can't use the L24 cam in an L28 P90 head, but you can run an L28 self-oiling cam in the L24.

Boring out the L24 .060 TO .080 over would be a better solution (IMO).

The L28 P79 and P90 head has a larger combustion chamber than the L24 head. The stock compression ratio with the f54 block and P79 or P90 head and flat-tops is just south of 8.5 to 1. The pin height of the L28 is lower which means your piston would come up short of your block deck (5mm?). Your C/R in that engine would seem to me to be awfully low.......It may work with a turbo, but I've never heard of anyone doing it. There must be a reason. All IMO.