Stock IM vs RBC IM

hey_mikey

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You know more about that than I do that's for sure. But what im trying to say, being non technical, is that the rbc is designed for a different motor that operates at a different complete rev range as our motors and thats why its only gaining peak hp on our cars. Im pretty sure an intake for our car could be designed that would sacrifice low end torque for high end hp and would work well. This is what the rbc does for the 8th gen. Problem is the high rpm power on the 8th is at a rev range our motor cant even reach. And the low end torque it sacrifices is in our high end hp range. What the rbc does show us is that gains can be achieved with an intake that breathes better. Im wondering if an intake thats tuned the same as our stock one but breathes better would give us a better high rpm power band? I want to clarify im not arguing with you. I just dont understand this the way you do on a technical level.
Sorry, I wasn't trying to argue either. I made the point earlier in this thread that the reason for the gain up top was for the RBC being designed for an application that revved to 8000+ rpm. I guess it's just hard to figure out a way that would make the theory easier to understand.

Is it possible to see improvements from the stock manifold? Of course. The real question is, how much improvement? That's where you're gonna run into problems. To design something properly for a specific application takes lots of time and skill, but the fact that the stock manifold is pretty good to begin with makes it hard to justify putting in the r&d for minimal gains when the market judges with their wallets. If tuners knew they could show large hp increases from the k24, especially since it's been out on various forms for a while, they would be putting more resources towards it for sure. The lack of options suggests otherwise tho.
 

Shagydishapopo

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Question can you install ZDX TB with our stock IM? Would it make any difference hp or tq wise? Ive tried researching this but Im just getting more confused with all the j35 and j37 with various inlets and such. Sorry Im noob with this stuff but wanting to learn.
 

squiggy

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Question can you install ZDX TB with our stock IM? Would it make any difference hp or tq wise? Ive tried researching this but Im just getting more confused with all the j35 and j37 with various inlets and such. Sorry Im noob with this stuff but wanting to learn.

Vit says it really will only add a bit more hp up top. You could probably install it, but would need an adapter plate made that would taper down if one isn't available. Even with the RBC, an adapter is needed.
 

tmkpres

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From what Pro Civic said with their Jseries TB to the OEM 9th gen IM it really close. I the J series TB (Accord) is an 80 mm tapering to a 70 mm. IIRC they said the inlet was a 68 mm on the 9th gen.
 

squiggy

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hotdogjohnny

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I have spoken to members privately, and they have said that if you like to drive in the upper rev range, the rbc really wakes up the engine, especially with a larger throttle body.
 

squiggy

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I have spoken to members privately, and they have said that if you like to drive in the upper rev range, the rbc really wakes up the engine, especially with a larger throttle body.

That is in line with what Vit has said. You are effectively trading mid-range torque and hp gains for a small amount of top end.
 

edd

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What so do you guys recommend, I do plan on going FI in the next year o or so, I would think it would be ideal to purchase the RBC prior to turbo rather than all in once.

Has there been any rumors or evidence that a company is developing a intake manifold specifically for our engines? (That doesn't lose mid range)
 
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squiggy

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What so do you guys recommend, I do plan on going FI in the next year o or so, I would think it would be ideal to purchase the RBC prior to turbo rather than all in once.

Has there been any rumors or evidence that a company is developing a intake manifold specifically for our engines? (That doesn't lose mid range)

My end goal is turbo. Last year I did RBC/ZDX/DP/Exhaust as prep. I also have the fuel pump already. Next year will be injectors/fuel rail/clutch. Year after that should be turbo. Essentially, I have been doing it in stages to enjoy each change in the car while waiting for the warranty to expire.

As far as a specially designed IM, I believe only Skunk2 has developed one, but I am unaware of the proven performance on it and it is expensive.
 

edd

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My end goal is turbo. Last year I did RBC/ZDX/DP/Exhaust as prep. I also have the fuel pump already. Next year will be injectors/fuel rail/clutch. Year after that should be turbo. Essentially, I have been doing it in stages to enjoy each change in the car while waiting for the warranty to expire.

As far as a specially designed IM, I believe only Skunk2 has developed one, but I am unaware of the proven performance on it and it is expensive.
I may just follow this same setup, I do think it would be beneficial to enjoy each change in the system. I did see that skunk2 IM, expensive is an understatement, I have not seen any reviews either.
 

squiggy

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I may just follow this same setup, I do think it would be beneficial to enjoy each change in the system. I did see that skunk2 IM, expensive is an understatement, I have not seen any reviews either.

Don't forget to work on your suspension as well. A rear engine mount will also be necessary in my opinion. It drastically reduces/eliminates wheel hop.
 

edd

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Don't forget to work on your suspension as well. A rear engine mount will also be necessary in my opinion. It drastically reduces/eliminates wheel hop.
Absolutely i installed Tein Advance coilovers, was going to focus on suspension and handing first but I'd like to have a semi fast go cart lol

Engine mount noted, thanks dude
 

Dennis Rockholt

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Absolutely i installed Tein Advance coilovers, was going to focus on suspension and handing first but I'd like to have a semi fast go cart lol

Engine mount noted, thanks dude

Agreed, suspension first so you can handle the go faast mods. Thats exactly what I am doing too...I went with Ksport coils, spc arms, and progress rear sway to start off with. And have the full exhaust system on as well as hondata and being tuned by vit...so not a bad way to start and work your way up to that quick little go cart!
 
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edd

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Cool guys, I was ready to look the other way on this RBC I'm convinced to stay with it for the big gains in the end, for turbo of course
 

Stealth

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Don't know if it helps, but I'm currently working on a project that should test out just what kind of numbers we can achieve with the stock IM on a NA build. I just sent off the stock TB, intake runners (fuel injector base), plastic OEM manifold, Throttle Body Body Spacer (P2R) and new thermal TB gaskets, and Thermal Intake Manifold gasket to maxbore.com. He'll be boring the TB from 64mm to 68mm, port matching the throttle body spacer, gaskets and OEM IM to match. He'll also be reworking the intake runners by porting the runners roughly 2mm to remove all the casting marks and smooth the runners similar to what used to be offered by P2R before they discontinued it a few months ago. This coupled with my current mod list: RV6 catless dp, Rick spec'd 3.5" Intake, Tsudo Exhaust, Flashpro. If interested, I'll keep everyone posted on the dyno results post tune with VitViper. SHOULD yield some decent gains and would provide a decent comparison to a similarly bolt RBC setup.

http://9thcivic.com/forum/threads/stealths-2012-si-sedan-build.9468/
 
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