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I have an 07 Si. The motor is internally stock for now. Injen SRI, Vibrant RH (2.5" collector), 70mm Invidia exhaust, and soon to come Flash Pro, 68mm-64.5mm tb, and probably some K2 mk2 or K2-11 cams depending on how ballin I am lol

So, which would yield better results, a custom ported RBC or a box stock RRC? I think I already know but I just want other opinions/advice.

Thanks,
Frankie


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being that you already have an RBC it may be cheaper to have it ported,but that leaves you with downtime.The biggest advantage would be having it ported according to your build.That said I felt a decernible gain in response and torque with just bolting the RRC on..now that I'm tuned it's alot better(I'm a fellow 8th gen owner aswell).
 

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if you have an rbc yes i guess it would be better to port it, but in a past issue of one of these tuner magazines the rbc ported only yielded a .3 hp gain. versus the rrc which produced an almost 10 hp over the rbc. food for thought
 

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if you have an rbc yes i guess it would be better to port it, but in a past issue of one of these tuner magazines the rbc ported only yielded a .3 hp gain. versus the rrc which produced an almost 10 hp over the rbc. food for thought
can't really trust that as an be all end all to the comparison...it is possibly that on another build a ported RBC could make asmuch of not more than an unmolested RRC.
 

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I was faced with the same decision not to long ago.

What my tuner told me and was what made me make my decision. If u port the rbc there is no room for improvement. (oem manifold speaking) But if u buy a rrc and maybe once feel like getting it ported then uve got best of both worlds.
 

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can't really trust that as an be all end all to the comparison...it is possibly that on another build a ported RBC could make asmuch of not more than an unmolested RRC.
That was on katmans intake manifold shoot out, all were tested on a stock k20r

And go with rrc it's what $300 or $350 shipped? How much is porting plus ship?
 

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I had compare the 2 manifolds on a stock motor and there isn't any difference in power between them
Just my experience

I will stick to rbc And spend the extra $200 in some else
 

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I had compare the 2 manifolds on a stock motor and there isn't any difference in power between them
Just my experience

I will stick to rbc And spend the extra $200 in some else
Which stock motor? I don't see how a RRC and RBC make the same tq in all the same places. When the two manifolds are alot different than meets the eye. I could understand not gaining anything if you have a stock a2. But if you have a R motor, you should benefit with a RRC over a RBC. With that being said, I have a RBC forsale and RRC so if you're interested PM me.
 

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Which stock motor? I don't see how a RRC and RBC make the same tq in all the same places. When the two manifolds are alot different than meets the eye. I could understand not gaining anything if you have a stock a2. But if you have a R motor, you should benefit with a RRC over a RBC. With that being said, I have a RBC forsale and RRC so if you're interested PM me.

And what's the difference between the r and the 02 motor?
According to you?

I had both motors and the a2 made more power then the R motor:cool:
A2 = 226whp R = 217whp both motors at the same dyno , same tuner same chasis and same bolt ons
This is just my experience
 

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Camshaft profiles and tuning are the major differences. Not sure on the intake manifolds between the two, but although they look the same, they have different part numbers.

Glad to hear you had a tired ITR motor!:rolleyes:

Camshaft profiles...higher comp and still the A2made more power :rolleyes:

The almighty R isn't worthy unless your looking for the tranny or to be cool because you have an "R"

BUT WHAT DO I KNOW:silly:

Ps
How much you want for the rbc ?
 

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Camshaft profiles...higher comp and still the A2made more power :rolleyes:

The almighty R isn't worthy unless your looking for the tranny or to be cool because you have an "R"

BUT WHAT DO I KNOW:silly:

Ps
How much you want for the rbc ?
Hey, you don't have to convince me, I bought the a2 and put all the good in it. Pretty sure both ITR and a2 have 11.7 cr...:confused:

Check my FS thread, I don't want to thread jack. Make me an offer. It's new and already modified.
 

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the a2 doesnt have 11.7 c/r.

OP get some better boltons bro, and to answer your question it all depends on how much the porting will cost you ?

I have an RRC and J35 throttle body combo on my si and really it opened it up some. Just depends on what you consider "value".

$450 for the combo minus $200 that you can sell off your stock combo seems worth it to me for the OE gains and zero downtime really.
 

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And what's the difference between the r and the 02 motor?
According to you?

I had both motors and the a2 made more power then the R motor:cool:
A2 = 226whp R = 217whp both motors at the same dyno , same tuner same chasis and same bolt ons
This is just my experience
Wow......what was the prior use of the motors? I just got a R swap from HMO and I didn't think an A2 would make over 220 with a RBC IM and Kpro (H/I/E)
 

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A few variables here.

Ported RBC vs. stock RRC on a K20? K24?

N/A or FI?

I think you'll find they all behave differently. I'm with Negrok20r - $200 spent elsewhere for what seem like minimal gains. (Plus I had got the RBC long before the RRC, lol).

Also...if you're having a ported RBC....depends on who's porting it. Check this out. Sneak peak.

http://www.flickr.com/photos/[email protected]/5952546560/in/photostream
http://www.flickr.com/photos/[email protected]/5952546382/in/photostream

In the end....numbers do most of the talking.


That being said, OP, I have a feeling for your setup the RRC will benefit you more.
 

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figment-the-dragon and one of his best friends have almost identical cars, identical. fig has a ported rbc, his buddy an rrc, figgy can pull til about 7k at which point the rrc walks away.

literally walks away.

you guys can do flow rates, discuss theory, analyze for days, in the end, the rrc will walk a ported rbc. if you dont believe me, great, fig will be happy to trade his ported rbc for an rrc
 

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figment-the-dragon and one of his best friends have almost identical cars, identical. fig has a ported rbc, his buddy an rrc, figgy can pull til about 7k at which point the rrc walks away.

literally walks away.

you guys can do flow rates, discuss theory, analyze for days, in the end, the rrc will walk a ported rbc. if you dont believe me, great, fig will be happy to trade his ported rbc for an rrc

In my case was the other way around so I wouldnt trade my pnp rbc for a rrc

Every motor is different I guess


Wow......what was the prior use of the motors? I just got a R swap from HMO and I didn't think an A2 would make over 220 with a RBC IM and Kpro (H/I/E)
The R came straight from a dc5 out japan

Right now Im running another a2 making 222whp same dyno same bolt ons same chasis
 
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