Datsun Roadster Forum-311s.org

This question doesn't really add much to this thread ,so I apologize.As an owner of both the 1600 and 2 litre U20 , I have to wonder if is worth the trouble and expense to stroke a 1600 , when you could start out with a U20 instead ? Again , please excuse the dumb question . Thanks .
Steve

IMHO, that's not a dumb question at all. If I could have obtained a U20 engine in the first place and replaced every moving part in it along with the machine work to rebuild it for under $1900, I would have....
When I look back on the whole idea, (and I DO, ...every time I drive it!) I've never regretted it. It's MUCH more of a HOOT to drive, than my stock 1600 motor, even though I had already rebuilt that one (the 1600 motor) several decades ago, but still only had a little over 200 miles on it. I don't race but I love the torque it has driving around town and the occassional "happy hour" on the highway...

I have often wondered where most of the bang-for-the-buck went though,...increasing the stroke or regrinding the stock cam to a 266 duration...

YMMV

I ran into some interesting piston website that shows the VG30DE pistons
are the ones to suit the R16 stroker with H20 using R16 conrods.
N8704
VG30DE
A2010-96E00
V6
Bore - 87mm
comp height - 32mm
Rings - 2 x 1.5, 1 x 2.8
Pin - 22mm x 67

This will allow on a 227mm tall r16 block 1.05 mm left from deck height

deck height 227mm - (Piston comp height 32mm + 41.5mm stroke + 152.45 r16 rod)
http://www.totopiston.co.jp/cat/piston/pist-ni.html

If the H25 crankshaft could be used then you can have a 2.2 litre H20 with good rod stroke ratio.
The H20 cranked R16 block gives 1.8367 rod stroke ratio.

Id be interested to see how Steve Heimsoth`s beast went with the big SS valves?

Can someone explain the difference between R16 rods and H20 rods? Is there that big of a difference or is it all in the pistons? It's my understanding you can build an r20 with the H20 crank and rods but with R16 pistons if you clearance the skirts for the longer stroke.

bump

anyone know it the r16 block is as tall as the H20? the R16 is 227mm supposedly

"anyone know it the r16 block is as tall as the H20? the R16 is 227mm supposedly"
Parts assemblies are interchangable, so it stands to reason it should be.


"Can someone explain the difference between R16 rods and H20 rods? Is there that big of a difference or is it all in the pistons? It's my understanding you can build an r20 with the H20 crank and rods but with R16 pistons if you clearance the skirts for the longer stroke."

R16 rod = 152.45 mm , U20/H20 rod = 144 mm, Pistons for all three engines have a pin height of about 41mm.

Yes you can use the R16 piston with the H20 crank and rods, it would put your compression up somehwere around 11:1 or higher if I remember correctly..........

EDIT: Just playing with some calculations which indicate it should be around 10:1 compression with R16 domed pistons.......Which is very workable with a performance cam.......

Daryl Smith wrote:Yes you can use the R16 piston with the H20 crank and rods, it would put your compression up somehwere around 11:1 or higher if I remember correctly..........

EDIT: Just playing with some calculations which indicate it should be around 10:1 compression with R16 domed pistons.......Which is very workable with a performance cam.......

These must be domed pistons then correct? Or will flat tops give the 10:1 and the domed higher? And if you use the dished forklift pistons, it will be lower, correct?



Also as an FYI to anyone interested.....

And not all U20 rods are created equal as well.

I have 10 U20 rods in a box at home plus (four more that will be used in my stroker) that have all been wieghed by my machinist. I don't have the numbers here at work, but, I can tell you that we ended up with something like six or seven different weights between the 14 rods. None appear to have been lightened.

tim

tputland wrote:

Daryl Smith wrote:Yes you can use the R16 piston with the H20 crank and rods, it would put your compression up somehwere around 11:1 or higher if I remember correctly..........

EDIT: Just playing with some calculations which indicate it should be around 10:1 compression with R16 domed pistons.......Which is very workable with a performance cam.......

These must be domed pistons then correct? Or will flat tops give the 10:1 and the domed higher? And if you use the dished forklift pistons, it will be lower, correct?



Also as an FYI to anyone interested.....

And not all U20 rods are created equal as well.

I have 10 U20 rods in a box at home plus (four more that will be used in my stroker) that have all been wieghed by my machinist. I don't have the numbers here at work, but, I can tell you that we ended up with something like six or seven different weights between the 14 rods. None appear to have been lightened.

tim

Agreed! That why balancing a motor is important. It is getting harder to find shops that offer balancing these days. The one good guy I knew is gone.

These must be domed pistons then correct? Or will flat tops give the 10:1 and the domed higher? And if you use the dished forklift pistons, it will be lower, correct?
Correct, by punching in the #'s on an online calculator, by changing the stroke length only, to 83 mm from 66.8, the static compression goes up to a hair over 10:1.
Flat top pistons would be in the low 9s unless you skim the head and/or deck the block.
Dished forklift pistons would be below 9:1 compression, I believe.

Anyone know the dish volume on the forklift pistons?

Is it evil to use the H20 block for a stroker ?

Steve

Is there a write up on what needs to be done to the R16 domed piston to work in a stroker motor? What exactly does 'trim the skirt' entail?

Thanks!
tim

Not evil at all to use an H20 block. Of course, that would mean it is not a stroker...

It would be just a beast then?

Steve

No, just an h20...

Darn!! I guess it will be an R16 then.

Steve