L28 Stroker Build - I need your advice :-)

[german240]

So the Delta grind is somewhat milder than advertised.. here is an actual cam sheet (actual grind): 

 

The good: I won't need performance retainers / springs, 0.160" lash pads should work. According to "how to modify your Datsun engine" this is about the max thickness allowed with stock retainers. The stock springs are fine up to 0.460" lift, too. 

The bad: I wanted a more agressive grind (we talked about 235deg@0.05"). I got 229/222 deg in/ex. 

Let's see how it is going to perform!

Edited February 23, 2017 by german240

[Diseazd]

Spent the morning with my good friend Eiji Hosomi (Datsun Spirit) today. I'm going to get his help building my new stroker motor , since I'm plowing new territory and want to make sure everything is right.....and no one knows right better than Eiji when it comes to L motors!  Here are the specs he gave me: 89mm bore, 83mm stroke (diesel crank), 90.5 mm x 1.29 mm gasket, .4mm above deck, 44cc head volume (I'm using my shaved P79 head) and 4cc piston volume....this should give approximately 10.6 to 1 compression ratio. He's using light forged pistons and rods and my head will have my Isky .490 lift Stage III camshaft. He wanted to go .560 lift, but if this doesn't float the boat, we can always throw on one of his famous N42 modified chamber wonder heads.....I'll think this will be enough juice for me though. Here's some pics I took at Eiji's shop.

Guy

Edited February 28, 2017 by Diseazd

[siteunseen]

Are SUs able to keep up with your cam?  I have a similar profile I'm going to put on an E31 and just today asked what my Webers would be worth.  I really like the SUs simplicity.

Thanks again Guy, you're help is invaluable. 

[Diseazd]

Yes Cliff....SU's will do fine....I only use SU's on all my L28's with Stage III Isky cams. I'm going to break in the stroker with SU's, see how they do, and if they work, I'll run em....if not, I may want to buy your carbs.  

[siteunseen]

Sounds great!  Those triples are intimidating sitting on my bookshelf.

[SteveJ]

2 hours ago, Diseazd said:

Yes Cliff....SU's will do fine....I only use SU's on all my L28's with Stage III Isky cams. I'm going to break in the stroker with SU's, see how they do, and if they work, I'll run em....if not, I may want to buy your carbs.  

I had to open up my SUs to 3.5 turns on the L28 that was swapped into my 260Z. I need to install a pressure gauge to see if the stock electric fuel pump delivers enough pressure.

Cliff's carbs are tempting, but my Z budget isn't that big this year.

[Patcon]

Those are some cool looking little pistons. Will be interesting to see how fast that spins up compared to some of your other engine builds...

Is Eiji doing the build or is he helping you gather parts and you're doing assembly?

[Diseazd]

I'm going to have Eiji build the bottom end. A stroker motor is something totally new for me. He knows which rods and piston heights to use with my Z Doc head. Also, with a stroker motor, there are mods that must be performed on the block. I want to put the rest together.....I just enjoy the build and want to feel like it's my engine. I'm thankful to have Eiji as a friend that will work with me and give me advice on building this motor......he's amazing!

Edited March 1, 2017 by Diseazd

[madkaw]

I'm going a similar route but will have Rebello just prep block for assembly. I'll buy his kit that works for his prep and just do the assembly.  

[german240]

Sooo.. I received my huuuge order from RockAuto Lots of parts! 240mm clutch/flywheel, brake/clutch cylinders, gaskets, water pump, fan clutch, OEM turbo oil pump, 280zx dizzy.. and much more. 

I also got my Delta cam and rockers back, it looks quite nice. Let's see how the cam performs. The cam lobes look slightly asymmetric. 

I am going to measure the combustion chamber volume of my N42 head as soon as I get it back from the engine shop. Then I'll decide which head gasket I'll order from Japan. Is there a source for 90mm gaskets? The only ones I've seen are 90.5mm (Kameari). 

 

 

 

Aaah, and a I received a picture of my F54 block ready to take the 89mm bore! 

 

Open topics right now:

1. Which damper should I buy? Is the $89 Professional Products damper acceptable? 
2. Should I remove/plug the oil bypass valve at the oil filter?

 

 

Edited March 15, 2017 by german240

[madkaw]

My buddy got one of those dampers and had to send it back- hole was undersized and couldn't mount it. Sent it back


Sent from my iPhone using Classic Zcar Club mobile

[german240]

My buddy got one of those dampers and had to send it back- hole was undersized and couldn't mount it. Sent it back


Sent from my iPhone using Classic Zcar Club mobile

I've read similar reviews.. Maybe it has to be taken to a machine shop in order to make it fit.