b2/y7 compression ratio
 

well the b2/y7 is running great. i was surfing here at hmt and decided to check out the new compression ratio after swapping on the y7 head, and i was amazed to see that it was an 11:1 ratio! now this is using the calculator program supplied by chirs's stickied post. currently i am running 89 octane, should i run 91 instead? either, i want to get better gas millage out of the motor as well as performance. i will be chipping my ecu soon and staying obd0.also the ecu is a virgin pm6. i should also be getting an adjustable cam gear and a delta regrind to help out even further. boost will follow after winter and when i pick up another ride(hmt buddies help there).

Re: b2/y7 compression ratio
 

I'd say the math is wrong, I came up with about 10.2 using Y8 HG

Re: b2/y7 compression ratio
 

10.1 - 10.2

Who gives a ----.

Good to hear its running. Ive been happy for a long time with it.

Re: b2/y7 compression ratio
 

well i more or so care if im using the right octane gas. i know what you mean by who cares though, but actaully i do lol. ive put 93 in the tank today and it seams to like it alot.

Re: b2/y7 compression ratio
 

the knology calculator and maybe even the zealautowerks one (can't remember) have the wrong figures for the y7 head.


the y7 combustion chamber is IDENTICAL to the z6...so use a z6 head for all calculations.

oh, ports on a y7 are different than a z6 though fyi.

Re: b2/y7 compression ratio
 

I did use the Z6 head cc's.......

only need 87 octance until you get above 11:1.

Re: b2/y7 compression ratio
 

ok lol, well i guess the hatch is gonna love this batch of 93 i put in for this week. though i have noticed a slight power increase in my midrange. i want another damn y7 cam so i can get it reground by delta!!! wtf i know someone has one damnit!!!!! :7

Re: b2/y7 compression ratio
 

Delta doesn't do Honda regrinds........just ships them out to somebody else :(

Re: b2/y7 compression ratio
 

Yay capitalism!

Re: b2/y7 compression ratio
 

if they ship them out they do it damn quick bone

i got my 272 grind back very fast. of course i'm only a few hours from tacoma.


104ish shipped is a pretty damn good deal too.