high or low Compression?

[myaccord7]

i want to biuld my head on my accord. i want to put direct port on my dcoe's. i didnt know if i should get my head milled or what. i know someone told me before but i dont remember if i whould get high or low compression. thanks



zach

[smufguy]

gettin the head worked on is the most important part of building up the motor if u wanna make serious power and im glad ur taking time to look into it. What kinda power are u willing to make or aiming for and that determines the head flow and the compression on the pistons. Do note that this will make you have a different cam with longer duration and a better oil pump (to be on the safer side if ur stock one is old). with some ARP head and crank bolts, you should be good to go. Dont forget the fuel and ignition either. And bump up ur injectors to the right size flow requirements.

[myaccord7]

well i dont want crazy horsepower (for a 3geez). i dont think i want to drag it, i want to do auto cross, cone racing. i have the openloop cam in now. i do have a spare engine i wanted to build, but what do you think about the compression? higher then stock or lower? isnt one better for nitrous and one better for turbos?


zach

[Mike's89AccordLX]

smufguy he said he wants DCOE's. He's carbed, so he doesn't have injectors.

I for N/A motors you want a higher compression. Turbo's you want lower since it will be better on your motor. If you do nitrous you still have have a higher compression motor but don't go too high. I would like to have either 11.1:1 or a 12:1 compression for my motor but I will probably do the 11.1:1 since I will be running nitrous. Wheneve I'm at the track or shooting juice I would set my adjustable cam gear to be retarded a couple of degrees.

-Mike

[A20A1]

He's talking about Nitrous injection
Look in my sig... there is a link to forced induction basics; turbo, supercharging, and a link to nitrous information.

Also in my sig is a link about sparkplugs, it tells you what to do/use when using nitro.

[myaccord7]

i dont have my dcoe's on yet, iam still making to manifold, but thats want i what to put nitrous on, my dcoes. so around 11.1:1 would be good ? just something alittle higher? thanks

zach

[A20A1]

Use the A20A3 EFI manifold flange since maybe you can use the injector ports to put in the nitrous ones.

[Mike's89AccordLX]

I would prefer to use direct port nitrous fogger system. But that's a good idea Mike where you would just put the nozzles for the nitrous where the injectors would be.

The way I'm going to do it is either do a direct port fogger system or get the weber nitrous plate.

[A20A1]

Check out the head work done to this A20
https://www.3geez.com/showthread.php?t=32450
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[ET2]

smufguy he said he wants DCOE's. He's carbed, so he doesn't have injectors.

I for N/A motors you want a higher compression. Turbo's you want lower since it will be better on your motor. If you do nitrous you still have have a higher compression motor but don't go too high. I would like to have either 11.1:1 or a 12:1 compression for my motor but I will probably do the 11.1:1 since I will be running nitrous. Wheneve I'm at the track or shooting juice I would set my adjustable cam gear to be retarded a couple of degrees.

-Mike

He's right but unless you have control of your timing with that high of c.r. ratio you will blowing lots of head gaskets, your best bet is to get forged pistons mill the head and the block use a steel head gasket with o rings on the block keep it around 10/1 c.r. with a wet kit and you will be cranking

[2ndgenludedude1986]

if u have the head plained its more compression.

[smufguy]

i know this sounds kinda lame, but 10.5:1 is your best bet. This being. 10:1 is just not enough to make the power you are looking for. But 11:1 is pretty right for a NA to make some good power at the top end. But 12:1 is just pushing it and its not a good idea for a heavy ass bottom end-ed motor like ours.

So i would say either stay with 10:1 or 10.5:1 if ur gonna use nitrous.