Honda D Series Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
901 Posts
Discussion Starter · #1 ·
ok ive done some research on 87-88 teg d16a1 flat top pistons, and 88-89 teg d16a1 dome top pistons. ive been told that they put down the same compression and hp numbers.
then..... what would be the difference between the 2? like ,is one actually better than the other? :slap:
 

·
Registered
Joined
·
1,303 Posts
with dome pistons(p29) you have no problems with piton to valve clearance. With the other I dont know.

In theorie flat pistons are better for boost, high dome are better for n/a.

But it doesnt metter, because both are cast pistons
 

·
Brokedick Millionaire
Joined
·
40,796 Posts
dig up the old d-series piston info page, you'll see the difference.

Both had domes :)
 

·
Registered
Joined
·
901 Posts
Discussion Starter · #4 ·
well the reason that i wanted to know is because i have a set of flat tops and the dood that wanted to buy them wanted to know that if they put out the same power , but had different designs. then why was one better than the other.
 

·
Registered
Joined
·
46 Posts
frrom what ive learned, domed pistons are for high compression and flat top are just regular. But if the wrist pin is moved down on the piston skirt that would move the piston up with would boost compression as well. So if thats the case then a flat top would be best for F/I and domed would be best for high compression n/a like u said
 

·
The H Badge is it!
91 crx
Joined
·
5,657 Posts
put it this way, if you had a d16 with flat tops in it, and then you switched to domed pistons, then the compression ratio would raise.
 

·
D-series Janitor
Front Engine Dragste
Joined
·
1,220 Posts
In theorie flat pistons are better for boost, high dome are better for n/a.
I hate to get nit-picky, but if you can use flat-tops and mill the crap out of the head, this is better than domes and a larger chamber. Flame front and hot spots tend to develop more with a large dome. Also the closer the valves are to the deck, the better the shrouding usually is.

But if the wrist pin is moved down on the piston skirt that would move the piston up with would boost compression as well.
If the compression height is the same, it moves the piston along down with the wrist pin. The key term is compression height, the distance between the pin and the top is the measurement not just where the pin is on the skirt.
 

·
Brokedick Millionaire
Joined
·
40,796 Posts
before you'll get into a pissing match, dig up the piston page.

Quench it!
 

·
Registered
Joined
·
901 Posts
Discussion Starter · #9 ·
i dont think anybody is understanding on what i am saying......
why are 87-88 OEM D16A1 flat top pistons and 88-89 OEM D16A1 dome top pistons putting out the same numbers in a D16Z6?????
and since they are. why would you prefer to get one over the other......
 

·
The H Badge is it!
91 crx
Joined
·
5,657 Posts
PG6-000
86-87 Integra
Browntop D16A1
total height: 59.80mm
compression height: 30.17mm
.889mm dome

P29/PM7-000
88-89 Integra
Blacktop D16A3
total height: 58.80mm
compression height: 29.06mm
3.30mm dome

so after looking over these specs, the piston with less of a dome has a taller compression height, im assuming thats how they yield similar results.

pictures found here: http://heeltoeauto.com/httech/YaBB.pl?num=1160787887
 

·
Registered
Joined
·
936 Posts
compression height, piston height (measured from middle of wrist pin to top of piston exluding dome height), dome height, dish depth, flat face/top, static compression, dynamic compression, quench area, squish area, coating...all different. understand what they all are and you'll get your answer.
 

·
Curious George
'99 LX Civic Sedan
Joined
·
3,569 Posts
Flat top are good too (stock to stock pistons), you can run higher timing advance, bigger cam with out valve to pistons contact, softer on ring land and rings themsleves and run lower octane gaz and give you more room for mistakes.

Z6 runs 9.2CR and higher timing than Y8 who has 9.8:1 and low timing, they make almost the same power out at the at real similar rpm range. Z6 has big dishes and circular chamber, and y8 has really small pistons dishes with square combustion chamber.

Make some research here we ever discuss about high compression and gain.
http://www.d-series.org/forums//showthread.php?t=57522
 
1 - 14 of 14 Posts
Top