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compression ratio d15b7

PostPosted: Sat Feb 21, 2015 2:58 am
by 92civicEGsedan
I just read on a few different sight that a d15b7 with the head shaved .060 will bring up the c\r to 11ish is this right? And if so what if the head was shaved .100 cause when I replaced my blown head gasket I took my head to get shaved cause it had over heated a few times and they said they had to take .100 off of it.

PostPosted: Mon Feb 23, 2015 4:03 pm
by teal_dx
Here's a compression calculator: http://www.zealautowerks.com/dseries.html

:thumb:

PostPosted: Tue Feb 24, 2015 2:36 am
by 92civicEGsedan
I found that last night when I was thinking about building a Frankenstein engine out of my d15b7 when I get my z6swapped in but thanks again teal

PostPosted: Tue Feb 24, 2015 2:45 am
by 92civicEGsedan
With using the d15 block and crank and rods that are 137mm length and I'm thinking y8 pistons with .300 machined off of the piston and bigger valve reliefs machined if that's even a choice I should have a 11.97:1 compression ratio with a 1.62:1 rod to stroke ratio combined with some head work upgraded valve terrain A A6 cam and ITBs made from a gsrx 750 or cbr900rr it should make for a sweet little N/A monster d

PostPosted: Tue Feb 24, 2015 2:47 am
by 92civicEGsedan
I also wouldn't mind a little more compression and maybe some bronze valve guides and valve seats with a 1mm or so bigger valves

PostPosted: Tue Feb 24, 2015 2:50 am
by teal_dx
I might reconsider if this is going to be a daily street car. In addition to requiring high octane fuel (Not sure what it will require, but I never put less than 92+ in my 10.5:1 CR y8 mini-me) but those ITB's are tough to tune. At 12:1 CR, I'm sure you're past pump gas.

PostPosted: Tue Feb 24, 2015 2:57 am
by 92civicEGsedan
teal_dx wrote:I might reconsider if this is going to be a daily street car. In addition to requiring high octane fuel (Not sure what it will require, but I never put less than 92+ in my 10.5:1 CR y8 mini-me) but those ITB's are tough to tune. At 12:1 CR, I'm sure you're past pump gas.

Nah the z6 is for the daily I'll be looking for a hatch to put this In or a crx and I was actually thinking about not going the efi route and getting a pair of mikuni carbs
It would be more of a weekend toy

PostPosted: Tue Feb 24, 2015 3:59 am
by teal_dx
92civicEGsedan wrote:It would be more of a weekend toy
:thumb: :thumb:

PostPosted: Tue Feb 24, 2015 4:05 pm
by 92civicEGsedan
And I just put in what I have done to the car as far as the head shaved with stock rods piston and crank and that made it 12.02:1 compression ratio I think it's safe to say I need a tune cause I just put the head on the engine and ran it as it was on pump gas :eh:

PostPosted: Thu Apr 16, 2015 6:19 pm
by 92civicEGsedan
After doing more research and playing with that calculator I'm looking for 144mm rods and a piston with about 21mm compression height that way the rod to stroke ratio is bumped to 1.70:1 and compression is dropped to the 11s

PostPosted: Fri Apr 17, 2015 3:00 am
by 92civicEGsedan
Just realized that compression height I was thinking of is probably impossible without loosing the piston rings haha