Anyone ever Stroke a 1500 Motor??

Ldino21 · Post by **Ldino21** » Sat Dec 18, 2004 7:21 pm

I am looking for options on what to do with my 1500, I am wondering if anyone out there has stroked one, either to 1600 or more?

Also what was entailed in stroking it, can I just swap in a 1600 Crankshaft?? Or is more involved.

I'd like to make the engine more powerful than stock but keep the stock look.

Lou Smaldino
66-1600
67-2000
65-1500

SLOroadster · Post by **SLOroadster** » Sat Dec 18, 2004 8:25 pm

Lou,
I'm not sure but with the 3 main motors you would need the U20 rods. I beleve inorder to to stroke a 3 main R16 you need the 1500 crank and the U20 rods, I'm not positive, but it could be a cool upgrade.

Will

DELETED · Post by **DELETED** » Sat Dec 18, 2004 8:27 pm

DELETED

ambradley · Post by **ambradley** » Sat Dec 18, 2004 8:37 pm

Putting a three-main R16 crankshaft in a G15 would actually de-stroke it, as the 1500 throw is longer but the bore much smaller. Doing the opposite (G15 crankshaft in an early R16) produces about 1800cc, I believe. This is one reason the R16 was considered a major improvement over the G15; shorter stroke meant faster and higher revving, while greater displacement means more horsepower. Not to say the G15 is a bad or unreliable engine, but there aren't stroking options for it that I'm aware of.

ambradley · Post by **ambradley** » Sat Dec 18, 2004 8:38 pm

I failed to mention that G15 and R16 blocks look identical, I believe, except for the ID tag. Swapping in an R16 but keeping the G15 valve cover will look stock until someone peers in deeper.

Post by **spl310** » Sat Dec 18, 2004 10:06 pm

They look pretty close, but not identical. Other than the stamp of G or R, the obvious give away is that the 1500 has, well 1500, cast into the side of the block in numbers that are about 2" or so tall. It is located right below the area where the G/R stamp would go. Now, rumor has it that some service blocks did not have the 1500 cast into them, but they are pretty scarce. Of course, 1500 parts aren't exactly falling from the trees...

Daryl Smith · Post by **Daryl Smith** » Sat Dec 18, 2004 10:56 pm

I have not heard of it being done, but it is possible. You would probably be looking at custom pistons though.
Ross @ Sports Imports offered me a 3 main H crankshaft (rare item) for a R16 project which would fit. He may still have it.
With the 80mm bore and 83mm stroke you would end up with about 1670cc. With a 1mm overbore 1710cc.
I had'nt thought about that combo before.....

ambradley · Post by **ambradley** » Sat Dec 18, 2004 11:53 pm

66wip,

Would that be for the H19? I believe that was 3-main whereas the H20 was (at least mostly) 5-main. Then again I'm not an engine expert...

Daryl Smith · Post by **Daryl Smith** » Sun Dec 19, 2004 12:38 am

Adam,
You could call it an H19. Just going from memory I'm not sure it had a # designation. I just remember H and 1883 cc's I believe. 85mm bore? I think it is on the "Early Datsun" website?

Daryl

DatsunBucky · Post by **DatsunBucky** » Fri Dec 24, 2004 3:30 pm

To the best of my knowledge, anytime the stroke is increased, the rod length has to be shortened, or the piston will stick out of the bore at TDC. Not sure, but shortening the rod 1/2 the stroke increase makes sense, all other factors remaining the same.

Daryl Smith · Post by **Daryl Smith** » Sat Dec 25, 2004 5:10 am

Given a certain "block deck height" you need a combination of parts which will equal that height.
The formula is "1/2 stroke + rod center to center length + piston pin height = ~block deck height"
For a stock 1500, 1/2 stroke = 37mm
rod c to c = 144mm
pin height = ~44mm
total = ~225mm
(I say ABOUT 225mm because the factory should make it close to the top of, but generally not even or over the top of, the block. Also these engines are OLD and have likely been rebuilt and the block "decked" to make it flat again, taking ~0.010"+ off. You MUST measure YOUR block to get it right.)

So, any combimation of parts you swap in should be close to 225 mm.
With the 83mm crank stroke you have a choice of custom rods or custom pistons. 1/2 stroke = 41.5mm
225mm minus 41.5mm = 183.5mm to share between rod & piston.

if you use the H20 or g15 rod (both are 144mm), 183.5 minus 144mm leaves 39.5mm for pin height for a custom piston.

If you use an R16 rod (152.45mm), 183.5 minus 152.45 leaves 31.05mm for pin height for a custom piston.

If you were to use the stock piston @ ~44mm, then, 183.5 minus 44mm leaves 139.5mm for your rod. That is 4.5mm shorter than the stock rod and the same as 1/2 of the stroke INCREASE.

Generally I believe it is cheaper to get custom pistons than custom rods, but you can check for yourself.

An option to the custom parts is to find parts from other engines that can fit with a little work. IE: Sometimes a piston can be found with the correct pin diameter, workable but non-standard bore, and a pin height that is close. See < http://home.att.net/~jason510/Motorspecs.htm > for some examples of how this can work.

Above ALL check with your Machinist BEFORE you embark on a project like this to discuss your options. AND make sure you get ACCURATE measurements - measure TWICE (three times?) and order once!! A custom part that doesn't fit is expensive.

Merry Christmas!!
Daryl

Datsun Roadster Forum-311s.org

Anyone ever Stroke a 1500 Motor??

Anyone ever Stroke a 1500 Motor??

Anyone ever stroke a 1500?

Anyone ever stroke a 1500?