Well when upgrading cams most of the tuner on here have suggested increasing your compression to suit.
So have you thought of upgrading your cams also?
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Well when upgrading cams most of the tuner on here have suggested increasing your compression to suit.
So have you thought of upgrading your cams also?
hey was i right ProEcu on the EGT??
not really, is there any advantage to upgrading cams after rasing compression, the other thing i gotta watch out would be the fact that compression is rased, would mean less of a dish in the piston which could get closer to the valves, especially in vtec mode. which is what i dont need.Quote:
Originally Posted by wynode
higher comp pistons have a dome shape like this
http://blkcrx.hondata.com.au/hondata...s/DSC00623.jpg
Do a quick search for threads on upgrading cams and see what people have said.Quote:
Originally Posted by MrJDMCivic
alright, im going to wack in the pistons, and see how i go, higher compression will cause lean,.right? , anyhow im planning on getting it dynoed before and after, so ill test with the new pistons, then ill buy a set of aftermarket cams, and retest it,. see if it will make any difference, just worried about the clearence, and the stock valves, also if i get the head port and polish, will i have to change the valves, cause i wana run type r power, if not more. with my forgies pistons cr12. and maybe some other mods.
are you using your stock cams?
You would definately get some power gain, but won't be alot. to fully maximise your PISTON, better get a set of cam gears with it and if you want, JUN stage 4 or spoon Class A cams.
Just get a Fuel press reg, fuel pump will do you fine. Clearance would not be a problem for sure but one good advice, don't oversize the cilinder head. and you don't need to change your Valves, if you got those type R Valves already.
If i were you, better find out how many VTEC those workshop done ever before deciding which one to go for.
Quote:
Originally Posted by MrJDMCivic
Dude, have you got a detailed spec sheet of the Pistons? What is the Piston Dome Displacement (measured in cc)?
The combustion chamber volume of P72 head and a PR3 head is about 1.1 difference P72 being 41.6 and B16A being 42.70
The reason im giving you these figure is because piston to valve clearance is an issue when you use bigger dome pistons in a p72 head... An even more so when you use bigger lift cams
Factory P72 pistons measured to be about 2.52cc where as you take a CTR piston (PCT) its somewhere 8.63cc due to the higher dome.
With the JE piston your running hopefully the valve reliefs are sufficient for the cams your using...
If in doubt you should get who ever building your engine to clay the motor to find exactly how much clearance you have to play. That way when you do decide to use cam gears to tune the motor you also know how much room you have to play when you go to advance/retard the gears.
FYI, using CTR pistons in a B18C2 motor and P72 head the calculated CR is ~ 12.0:1 assuming std bore and 3 layer OEM gasket.
http://www.c-speedracing.com/howto/c...c/compcalc.php
This V8 guy doesnt know how well Honda motors are built from the factory :thumbdwn:Quote:
Originally Posted by MrJDMCivic
this is the piston and the information about it, what do you think.? it turns out it was 11.5 and not 12 so i think the compression ratio is the same as the type r, the other thing is, im going to bore out my block .5 mm., and i was wondering the stock gasget and stock head should be fine, right?
http://vanortonpaper.com/pic/piston.jpg
i think the * symbol specfies that its the stock figure. example being the stroke and rod length
Ya that means stock numbers. The ITR has 10.5:1 CR. As for the rod length and stroke the CR numbers are based on using that size rod with that stroke. If you change the rod the CR will change and so will the stroke. CR is also based on a stock head and head gasket. If you mill/deck the block and head the CR will change. Thicker/thinner gaskets will change the CR.
http://www.strathlan.com/TEK/images/jeb18c5specs.jpg