H20 Questions..

67 1/2 1600 · Post by **67 1/2 1600** » Tue Aug 16, 2005 3:23 am

I found a H20 core. Its frozen and looks exactly like a R16. I am confused on the head. Do you have to match ports on the H20 head or the 1600 head?? I plan on rebuilding it anyway so any ideas,perfomance compared to R15 etc or info in it would be nice... Where are you Dan?

Joaquin

DELETED · Post by **DELETED** » Tue Aug 16, 2005 7:12 am

DELETED

Daryl Smith · Post by **Daryl Smith** » Fri Aug 19, 2005 3:36 pm

I saw an H20 head once that I couldn't tell the difference between it and an R16 head. Although the H20 was cast Iron. Also read somewhere that Someone used the H20 head on their stroker.

Here: http://www.311s.org/phpBB2/viewtopic.ph ... hlight=h20

The standard H20 head uses the same size valves, and the ports looked the same on the head I saw, so you likely could bolt up the R intake and exhaust manifolds.

Whatever head you use, I would recommend port matching, and at least some porting of the head to increase the flow.

mikew · Post by **mikew** » Mon Aug 22, 2005 9:41 am

All of the H20 heads that I have seen have the same valves/ports as the R16 head. I have read in various forums however people who swear that the ports are much smaller. Maybe some of the forklift model H20's had a different head?

Only real difference between H20 and R16 head:
- H20 is Cast Iron
- Except for very early ones, they have a 2-bolt thermostat housing making them incompatible with the R16 filler neck. You need to have a cap on your radiator.
- H20 has single valve springs, which will limit it's ability to rev if you improve the breathing. Easy fixed.

Note also, if you use the R16 but retain the H20 pistons you will have a horribly low compression ratio. Some people have bolted the 1500 head to the H20 bottom end as a simple way to raise the compression.

Since you are rebuilding the H20, I'd suggest you use an R16 head with the R16 pistons, or use the H20 head and U20 pistons.

Lars · Post by **Lars** » Fri Apr 14, 2006 11:32 am

mikew wrote:Note also, if you use the R16 but retain the H20 pistons you will have a horribly low compression ratio.

Just to verify that I have understood this correctly:
If I replace the head of a H20 car engine with an R16 head, the compression ratio will drop? According to the H20 engine manual the compression ratio is 8.2:1 with the H20 head.

steve68 · Post by **steve68** » Fri Apr 14, 2006 12:39 pm

The h20 pistons are dished..5ccs i believe, you would need a shaved r16 head to have good compression with those pistons..and i have one!!! with the r16 pistons it pressured checked at over 200!! stock is 170 i think. but it woul dbe perfect for an h20. (im moving to a u20.) ill trade ya the head for the solexs

steve

Daryl Smith · Post by **Daryl Smith** » Fri Apr 14, 2006 1:36 pm

The best way to determine that would be to measure the volume of the combustion chamber.

I measured a couple of aluminum R16 heads and both ranged from ~47cc to almost 49.5cc.

I don't know what the H20 combustion chamber looks like or if it has the same portion "scallopped" out to allow clearance of the R domed piston.

Without that "scalloped" out portion you would have the "potential" of a larger "squish" area and possibly a more efficient combustion chamber (ie:more power).

I am trying to find out the volume and shape of the H20 combustion chamber.......Anyone have some pictures/volume measurements?

Victor_laury · Post by **Victor_laury** » Fri Apr 14, 2006 2:44 pm

The problem is - there is more than one H20 head - There was the forklift/emergency generator/yard tug industrial motor - this one is not suitable and you will be swaping this out for an R16. Great for running a Ag pump but not a car

There's the Medium truck head - like the one Dan had

There's the Cedric car - which I thick is the same has the medium truck
either of these are pretty usable as is, but a cam change will only help.

Just like the "J" motors - They had lots of varents for indus. uses

Lars · Post by **Lars** » Thu Jun 22, 2006 12:25 pm

mikew wrote:Since you are rebuilding the H20, I'd suggest you use an R16 head with the R16 pistons, or use the H20 head and U20 pistons.

Is it possible to use the R16 head with U20 pistons in the H20 engine?

If this is possible, what compression ration can be expected with this setup compared to R16 head and R16 pistons in a H20?

mikew · Post by **mikew** » Sun Jun 25, 2006 6:36 am

Actually, I'm not sure about using dome top R16 pistons in the H20 with R16 head. You might have clearance issues.... but I don't know for sure.

You can definitely use the U20 pistons in the H20 - this is what I run in mine, with an H20 head for a compression ratio around 9.8:1.

mike