Cam Question? - Honda Forum / Acura Forum

hay112 · 08-08-2002, 08:24 PM

First of all i no nothing about cams. But anyway, is there any cams out there that i can install without changing any other parts,....? If not what cams can i install that will need the least amount of other parts...?

JAYMAN320 · 08-08-2002, 08:30 PM

You can use OEM ITR/CTR cams...no upgrading of the valvetrain is needed, as well as Skunk2 stage1 cams. But I suggest upgrading your valvetrain BTW.

hay112 · 08-08-2002, 09:03 PM

What gains would gain from those....my redline would be stay the same right?

hay112 · 08-08-2002, 09:11 PM

Also what kinda of gains can i get from aftermarket pistons?

JAYMAN320 · 08-08-2002, 09:22 PM

What kind of car do you have bro? Im guessin you have a VTEC motor, cause if not these cams dont apply to you.

Anyways... heres a dyno sheet from Skunk2, a comparison of the ITR cams vs. Skunk2 stage 1 cams:

------Green Skunk2 Racing Stage I VTEC Cams
----------Factory ITR Cams

It may look good by the dyno sheets but it also depends on what application you're goin to apply with these cams, be it AutoX or Drag.

The ITR/CTR cams were designed for max midrange power...their cam profiles were designed for autoX/track usage. They are ideal for daily driving were good idle is needed as well as good power throughout the power band.

The skunk2's make power from 6000rpm+, You loose the mid but gain it back up on top. These are intended for daily driving/weekend drag events.

These cams are mild...both are very good for daily-drive use. But for higher hp gains you should look for a cam with longer duration...ex; skunk stage II, JUN stage III's. These cams are considered wild because of the need for a valvetrain upgrade.

First decide the style of driving you intend on doing than go from there, from my experience get the ITR cams. And most importantly get your cams tuned so you can reap the most benefits.

hay112 · 08-08-2002, 09:54 PM

So how about Pistons? What compression ratio can i go to, without chaning out any other parts. maybe just retarding the timing a little...what pistons and ratio would u recommend?

appreciate the help

JAYMAN320 · 08-08-2002, 10:58 PM

I always like to stick with OEM parts, check out the c/r chart:

A0 = USDM spec.
00 = JDM

P73 = Integra Type R
PCT = Civic Type R
P72 = B18c-GS-r
PR3/PW0/P30 = B16a Civic

• PR3 = 89-91 B16A Piston, CR = 10.2
• P30 = 92+ B16A Piston, CR = 10.4
• P61 = B17A Piston, CR=9:7.1
• P72-A0 = US B18C1 Piston, CR=10:0.1
• P72-00 = JDM B18C Piston, CR=10:6
• P73-00 = JDM ITR piston, CR=11:1
• P73-A0 = US ITR piston, CR=10:6

Approximate Compression Ratios
(when using 'R' Pistons in B-series engine(s)):

• Stock B16B CR=10:8
• B16B pistons in B16A CR=11:1ish
• B16B pistons in B17A CR=11.4ish
• B16B pistons in B18C w/GSR head CR=11.8 or more
• B16B pistons in B18C w/ITR or B16A head CR=11.6 or more
• B16B pistons in yo ass CR=15:1...too high !!!
• P73 US pistons in B16A CR=10.4ish
• P73 US pistons in B17A CR=10.6ish
• P73 US pistons in B18C w/GSR head CR=10.8-9ish
• P73 US pistons in B18C w/ITR or B16A head CR=10.6
• P73 JDM pistons in B16A CR=10.6-7ish
• P73 JDM pistons in B17A CR=10.8ish
• P73 JDM pistons in B18C w/GSR head CR=11.3-4ish
• P73 JDM pistons in B18C w/ITR or B16A head CR=11.1

*
FF Squad Website

It all depends...the higher c/r you go, the more power, but timing is very important...ignition retarding should be adjusted and the use of higher octane fuel is needed to fight detonation. Cam profiles must be takin into consideration....

"A mild cam with an early intake valve closing point will work well at low RPM. But at high RPM the intake valve will close before the maximum amount of air/fuel mixture has been drawn into the cylinder. When this happens performance at high RPM will suffer. If a high static compression ratio is used with a mild cam (i.e. and early intake valve closing point) then the mixture may end up being "over-compressed". This will lead to excessive compression losses, detonation and could even lead to head gasket or piston failure."

The Itr cam has an early intake valve closing point...that is how it gets its great midrange power but lacks the top-end to that of a wildercam. Compared to the characteristics of a more wild cam ex; Skunk2 stage II you'll compromise low end power because of the late valve closing point...but during high rpms more power is being made because more air/fuel is allowed....look at example

"On the other hand, an aggressive cam with a late intake valve closing point will work well at high RPM. But at low RPM the intake valve will close too late for sufficient compression of the intake charge to occur. As a result torque and performance will suffer. If a low static compression ratio is used with an aggressive cam (i.e. a late intake valve closing point) then the mixture may end up being "under-compressed". Thus a high performance cam with long duration should ideally be combined with a higher static compression ratio. That way the engine can benefit at high RPM from the maximized amount of intake charge afforded by the late intake valve closing, and still achieve sufficient compression of the mixture as a by-product of the dynamic compression ratio."

My reply is very sketchy...read the below sites so you can fully understand my reply and how static compression and cam profiles correlate with one another. Good luck

For a more detailed explanation read these websites:

Compression Ratio

-How to read uncorrected compression ratio...

ps-I know someone is goin to jump on me because of my reply...sorry

randyman · 08-09-2002, 12:28 AM

another trick that u can do when using ITR or CTR cams is to get some ITR intake valvesprings. install them in lieu of the gsr intake valvesprings. keep the gsr's intake valve springs and move them over to the exhaust side. the gsr's intake valvesprings are just like the ITR's exhaust valvesprings.

hth.

hay112 · 08-09-2002, 04:20 PM

What gains can i expect if i went to an 11:1 compression ratio...and if i did what other components do i need to upgrade?

JAYMAN320 · 08-09-2002, 04:30 PM

Everytime you bump up the c/r youll always make more power. Everything is given when you upgrade the pistons, rings and wrist pins. And you also wanna check the cylinder walls for any scoring or wear.

B18Chillin · 08-09-2002, 07:13 PM

i been thinking about a cam upgrade too. something along the lines of a CTR intake cam and ITR intake valvesprings like randyman mentioned a few posts ago. how long would this be alright without upgrading other internal parts (i.e. pistons, rods, etc.)??

any suggestions on cam gears?

randyman · 08-10-2002, 04:45 AM

Quote:

Originally posted by B18Chillin
i been thinking about a cam upgrade too. something along the lines of a CTR intake cam and ITR intake valvesprings like randyman mentioned a few posts ago. how long would this be alright without upgrading other internal parts (i.e. pistons, rods, etc.)??

any suggestions on cam gears?

ur going to be alright with ur bottom end. the CTR and ITR cams are not too wild. in fact u can get away with ur stock springs as long as u don't raise ur redline.

hay112 · 08-10-2002, 02:58 PM

my import shop said i would need to upgrade my head gasket and oil pan gasket, and other stuff, if i wanted to up my compression to 11:1....is that true?

If not what parts do i need to make my engine last with the upgraded pistons?

I just want to make sure, cause i need this car to last.

thanks for all your help guys

randyman · 08-10-2002, 06:49 PM

i run 12-1 compression and am using stock b20 head gasket and stock oil pan gasket. u might want to invest in some 310 cc injectors too to be on the safe side. ur engine will last depending on how often u abuse it (taking it to redline for long periods of time).

WOT · 08-10-2002, 09:35 PM

he must have too many oil pan gaskets in his inventory and needs to sell them....