I've talked with qbsi and he suggested that I get the CTR cam (intake). Now my questions are as follows. Should I get the exhaust cam as well? Will these cams be good for my SC'ed Si or are they only good for NA applications? Should I also upgrade to stronger inner and outer valve springs? If so, will ITR ones do the job?

I'm planning on doing a B20 swap and run at least 10 psi on the SC, but that's later on down the road. Any help would be greatly appreciated.

 

if you get a CTR intake cam you will look like this on your cam profiles:

11.5mm lift intake, 243 duration 18BTDC intake valve opens
9.5mm lift exhaust, 227 duration 7ATDC exhaust valve closes
0,0 yeilds 25deg of overlap biased toward intake duration


for boost tuning, you should bias the breathing toward exhaust duration.

it looks like this:
10.6mm lift intake, 230 duration valve opening at 10BTDC
10.5mm lift exhaust, 235duration valve closing at 10ATDC
0,0 yeilds 20deg of overlap
0,-3 on crank yeilds 17deg of overlap biased toward exhaust duration.

you can further tune this way and slow the intake charge so your engine
can exhaust all the air without losing the opportunity to make power from
it. under boost, the engine wants to throw so much air into the motor, the
exhaust cam cant keep up at high lift and high RPM. By not buying the
intake cam and getting the ITR exhaust cam, you will help this process
along. also, go here: http://www.theoldone.com there are several SC'd header
suggestions here to help scavenge power from your boosted motor.

The CTR cam setup with both cams would be good for all motor mainly.
I have talked with several tuners that have made power from the way
I have described boosting over 8lbs. It helps reduce heat in the engine
and creates more mechanical efficiency.

John Wilson @ http://www.LHTperformance.com told me this when I was considering
going that route and was talking cam profiles with him. Also, crane cams have
some sweet setups for boost that eliminates VTEC alltogether with roller cam
followers... totally monster. This is meant for BIG BOOST cars that need a
constant supply of oil and VTEC engines fluxuate ALOT. Also, having a more
linear engine would make more sense to boost... VTEC at least can be adjusted
to help you get into your peak boost RPM. Endyn also has a supercharger kit
for the Bseries car that eliminates VTEC and can boost harder because of it.

Just some stuff to consider.

Mike

 

Thanks for the info. Actually I forgot what cam qbsi told me to get, it could of been the exhaust cam. I'll email him and make sure.

Thanks again for the info, definitely helps me out.

 

yea man tuning for boost needs lift and duration
bias toward the exhaust side, it helps pull the mixture
in while the intake cam being lower duration helps
the engine not bite off more than it can chew...

remember the laws of effective compression...

 

i was under the impression that for turbos, high lift with less duration would be preffered?

 

correct, this is why you would do like I suggested above
keep a stock intake cam and go with a exhaust cam that
allows the engine to breathe more under boost.

thats why when you look at cams for boost they look like this:

390/396
260/266

or for GSR/ITR
a for instance for musing purposes:

230 -2 deg /235 + 3deg
10.6 lift/10.5 lift
228 intake duration /240 exhaust duration
8BTDC Intake
7BTDC Exhaust
15 deg of overlap