I've searched and searched!
There's so many answers that i have no idea what's right.

I have an ITR block in need of a rebuild.
As far as i am aware from reading on this site PCT pistons will send the CR sky high. I'm only looking for a CR of about 12.0:1 and thought B16 P30's would be suitable.
According to C-Speedracing the CR will only yeild 11.3:1...

So, does anybody know what CR P30's would give in an ITR?

I know these kind of questions have been done to death but any help is greatly appreciated

Cheers,
Ian.

 

This site is more accurate than the c-speedracing.

http://www.clubcivicquebec.com...f.php

Good luck w/ the build

 

Cheers but it still seems a bit out

 

The compression calculator has given you a fairly accurate estimatem now the rest is up to you. If you want more compression, you'll have to either use a thinner head gasket and plain the head a little or use custom pistons. The question is...why do you need 12:1 compression?

 

I would shoot for 11.5-11.7:1 CR just to be a bit safer. Some flat faved valves should get you to around 11.4-11.5:1 CR, a thinner HG could get you around 11.6-11.7:1. But why is 12:1 your goal?

 

The reason I was aiming towards a CR of 12.1:1 is I'd like to run either Skunk2 Pro1 cams or better yet Pro2's.
I noticed on the compression calculator that the piston to deck height is slightly larger with P30 pistons over P73's, am I reading it right? If so does this mean there would be more room for valve to piston clearance as my head has been skimmed about 20tho?

Thanks again,
Ian

 

You don't need to run that much compression to make those cams work. It would be better to have a little more displacement to get the most out of the pro 2's though. You don't have to worry about the P2V issues running those stock pistons and pro 1's unless you go crazy with your cam gear adjustments.

 

Thanks,
After a little more searching I've decided to go with Skunk2 Pro1 cams as I think the Pro2's are too big for a 1.8L. (?)

I was talking to my engine builder today and am pretty confident that I'll have a strong reliable engine, spec as follows;

B18C Block (JDM ITR)
ITR Crank
ITR Rods
ITR Girdle
P30 Pistons
Hasting Rings
ACL Race Bearings
ARP Rod Bolts
ARP Head Studs
ITR Head
Skunk2 Pro1 Cams
Crower Springs & Retainers
ITR Valves
TODA Cam Gears
2.5" Straight Through Custom Exhaust (Don't need a cat here )
S200

Not sure on a header yet, I currently have a DC Sports 4-1 Stainless but I don't think it's up to the job anymore. Does anybody know which header i could use on a 91 CRX (UK VT, same as JDM SiR) ?


Thank again

 

That should be a good strong build for you

 

Cheers,
Any more opinions?

 

Did you get my pm?

 

Sorry about that, I've replied now