Stealth's 2012 Si Sedan Build

Tuning is complete and the car was redelivered back to me. 94-96 degree weather. Realistic numbers from the graph are 245/202 before factoring smaller wheel diameter, 235/194 if factor a 4% reduction for wheel diameter. Car feels completely different. Valve last adjustment done prior to tuning. Exhaust was way off at +30 on each valve and intake was of as well.
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now take about 3-5 peak whp off the top and factor in 15-20 wtq in the midrange by going factory intake manifold. You got a beast my friend, but hp is a product of tq without that hp means nothing i think you should have kept the factory intake manifold or even tried an RBB manifold for 06-08 tsx k24a2. whats next E85?!
 
Yea i was like, 12+ HP for -17 TQ? unless you drive in the high rev's all day or track/autoX consistently when would you use that extra 5 HP? the torque is the git up and go, I plan on keeping the stock manifold but getting it port matched along with the TB and a spacer. I think it would go good once i get the PRL CAI and the Tsudo DP & Cat back.
 
now take about 3-5 peak whp off the top and factor in 15-20 wtq in the midrange by going factory intake manifold. You got a beast my friend, but hp is a product of tq without that hp means nothing i think you should have kept the factory intake manifold or even tried an RBB manifold for 06-08 tsx k24a2. whats next E85?!

I gained over 21+ whp over my last dyno with the stock manifold. Also, please keep in mind that the 235 whp figure was the lowest dyno of the day. Just was giving a worst case scenario. This wasn't a standard rbc which in the original test yielded 5 whp on the top end. It was ported at the tb Inlet as well as the runners. If you compare my previous dyno to current you'll find that I didn't lose that much torque but gained a much more linear power band and top end. The car is ready for e85 if I can source it locally.
Next project is more weight reduction. Lightweight odyssey battery will be here tomorrow and shed another 15 lbs off the car. Now I'm looking into a lightweight idler pulley as well as cutting the water jacket off the manifold for less heat soak.
 
21whp because you change the the intake to prl, the throttle body to J37, pulleys plus the tune was dialed in completely. from manifold to manifold rbc isnt worth the swap over the stock one especially you closing the gap with it being ported! So what does your ported RBC make over a NON-Ported RBC?!
 
Ambient temps were negligible when you consider I swapped from a 3.5" Rick Spec'd intake which pulls air from behind the headlight as opposed to other Sri's that pull from the the downpipe area. The j37 was thrown in the car before final tune was complete with Vit. We had already done power pulls and we're working in part throttle tip in so the 214 whp was realistic. Vit already proved that the gains with a Zdx are minimal. Now with a ported rbc...who knows? Simply as a reference point, my tuner has a 2012 si coupe with skunk2 cai, same pullies, same downpipe and Tsudo + tune and made 215 whp (oem manifold). I know that each car is different, but this shows relatively that an oem manifold is maxed around 210-215 whp when looking at all motor. I spend more time in the mid-high rpm range so the rbc was a risk I was willing to take. I can't compare a non-ported vs ported rbc because I obviously did t buy both and install/dyno. But my tuner just finished another rbc tuned car (non-ported) the week prior and it made ~225 whp. Hopefully that helps explain things a little better. I'm working something out where the car will go to the drag strip sometime in July to compare trap speeds with my tuners car to see what difference we're looking at. Should be a good reference point between to both fully bolted civic si's from an rbc vs oem standpoint. Just need to get some springs first to help with launching.
 

Exactly my point. 7-11 whp on the top end which make this a perfect fit for someone like me who spends a good deal of time in the upper rpm range. Also keep in mind that this was a standard, non-ported rbc and not ported at that tb inlet as well. With the extra money spent on porting to close the torque gap and gain a few additional horsepower on the top end, made this a win win for me. Driving the car I can tell you that the power difference is much more noticeable as well as much more linear. I would never consider doing the swap with a basic RBC manifold just to gain the 5 whp on the top end....not worth it. I'm anxious to see what happens when I have the manfiold cut open and have the plenum ported and the water bypass completed. I'd be happy to pick up another 4-5 whp. Lightweight battery gets here today so she's coming together slowly...
 
Have you considered new cams?
Since you want the most power out of an N/A setup.
 
Have you considered new cams?
Since you want the most power out of an N/A setup.

I would love new cams but since they aren't available just yet, I will have to wait. I have spoken with marquis over at Kmod performance and he's currently working on k24z7 cams but has more testing to do at this point. Until we can get the exhaust side of the head to flow we won't make the most of any set of cams. Kmod offers cylinder head packages that can easily go over $1500-2000 for stage 2+ but I will probably wait until the cams are out to do it all at once. My dyno shows that I have potential to make power up to 8k, so I might try upgrading valvetrain to make it safer to rev that high and see what we get.
 

I was aware of these, but there's several problems. Bisimoto cam out with cams over a year ago, but never provided any additional information such as dyno results even when requested by multiple interested parties. Also, the average turnaround time for cams is 2-3 months once payment has been submitted. In addition, I find $1500 for a billet set of cams to be excessive considering I would have to spend $400-500 for valvetrain upgrades and several hundred for install. No doubt it's a quality product, but I find it concerning that Skunk2 / KMod Performance, etc all have hit multiple hurdles with camshaft development for the k24z7 and have been working on this for the past year, but somehow Bisimoto solved this over a year ago and his competitors haven't bought his product, reviewed how he did this and used the same logic to continue with their design? Just doesn't seem to add up. I was speaking with Michael Hinton from Axion Industries and he is supposedly coming out with a head/cam package in the new few months that I may end up going with that addresses not only the flow issues, but ensures a complete bolt on kit. Perhaps if I could find a consumer that has his product installed and could speak with them about the product and post sale impressions, it might make me more comfortable with laying out $2000 for cams that are untested in the public.
 
im not saying the RBC ported or not isnt a Cool or beneficial mod. im just saying that what benefits you get arent all hyped to what the community thinks unless done right, cut and ported! secondly, i also think theres other options out there for intake manifolds that would be a better fit for our k24z7
 
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