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Arouse the DAMPFHAMMER!
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but there is no experience in calculating their sizes :)
Concerning the dimension calculation there is experience and knowhow here, also there are valid tests, done by 6spd_EK. The main issue of the RSP intake manifold is the stock plenum design. Plenum volume and design as same as the air inlet location and design are the main factors to support better VE. The last where already investigated by BlackNDecker and 6spd_EK, but they didn't post a result of the final dyno...maybe it didn't happen yet?!

Markus
 

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Concerning the dimension calculation there is experience and knowhow here, also there are valid tests, done by 6spd_EK. The main issue of the RSP intake manifold is the stock plenum design. Plenum volume and design as same as the air inlet location and design are the main factors to support better VE. The last where already investigated by BlackNDecker and 6spd_EK, but they didn't post a result of the final dyno...maybe it didn't happen yet?!

Markus
Let's hope that this happens, it would be nice to see the real results
 

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Arouse the DAMPFHAMMER!
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Let's hope that this happens, it would be nice to see the real results
You are not interested in doing your own plenum and to test it?

I designed my own intake manifold as the stock pieces, no matter if PRC, PRB, RBC, RRC or RSP, are designed for different requirement specification. Mine is done in favor to increase VE for a wide engine speed bandwidth. There are some clearance related compromises to get it done, but based on a stock IM it is pretty challenging to improve the VE numbers without loosing the cost target thing. 6spd_EK already showed it, it is possible to get into the RRC VE level over engine speed bandwidth with an modified RSP, but to win 10-15 Nm where the RRC's VE is declining is not possible, without modifying the plenum and plenum inlet. Mine is designed to improve that and midrange too, giving me a better cost-VE points-relationship.
 

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OK. Well now I know the heads are identical, including the valves. The cams are identical too. Only difference is that RSP manifold which looks damned clever but has that stupidly small throttle body. Luckily it's easy to change.

Sadly it won't fit in my engine bay, so it's for sale.
 

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Arouse the DAMPFHAMMER!
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What would be the best intake manifold to go with for drag cartel 2.2? My power is maxed out at only 8200rpm...should I go with RRC? Currently stock ported RSP / FN2 euro R

thanks...
I've seen your graph a couple of days ago. Dario sent it to me. I would say that the header and intake manifold is holding you back if you want to rev it higher. Ditch the japspeed manifold and go with something like asp 4-1 with megaphone or k-tuned bigtube header. I know that there is not alot of options for FN2 chassis so you would have to get it custom made. The Tegiwa, Japspeed and Toda look exactly the same. I think that Japspeed and Tegiwa copied the Toda manifold and I haven't seen a better design on the market for FN2 chassis.

The stock RSP intake manifold is not that bad if you modify it. We have made good torque with it on a stock EP3 engine with Mugen intake and Toda header. We modified the plenum chamber and shortened the stacks inside so the torque peaks later. I've attached the torque comparison graph between yours and my brothers with modified RSP intake manifold. You can see that your torque peaks a lot sooner than on the brother's EP3, but it holds it further, probably because of the DC 2.2 cams.


If you want better power and higher in the RPM, then go with the RRC manifold. It's the best of the OEM ones.
 

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Thank you both!!

My RSP is only ported...the biggest bottleneck is RSP in my case i think...but I think skunk2 pro series manifold would be even better than RRC?

RRC is awesome I agree but seen many comments that with camshafts skunk2 is way to go...i would rather get OEM as I like more OEM stuff but unsure of the peak numbers with skunk / rrc.
 

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Have a question, why would it be better for torque to peak later in the rpm band?
I prefer as much torque as possible early in the power band
 

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Have a question, why would it be better for torque to peak later in the rpm band?
I prefer as much torque as possible early in the power band
Lower torque peak rpm is better for street and DD, higher is better for track and drag. Moving torque up will generate more power as power is torque * rpm so you will need to spin higher to feel the power.
 

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Exactly what deibral said. Shortening the intake tract makes the peak torque move higher which means more power, that is if the rest of the engine is capable of producing in the higher rpm.
We did that because the stock RSP manifold usually peaks at 7800 rpm, and wanted more power after that. We didn't gain at the top because of the intake air box and exhaust manifold, which we will change in the future.
 

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Arouse the DAMPFHAMMER!
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Haha Markus. Yes it getting a little warmer here as well. I have still been tinkering. I got your PM. I hope to have that info this weekend.
Hello 6spd_EK, are you ready with your RSP modification? I am still waiting to see results of it from the dyno. In between my DAMPFHAMMER IM was aroused.

IMG-20190430-WA0000.jpg

I hope to see your IM tuned before the DAMPFHAMMER engine was tuned :D.
 

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I have a ported RSP manifold for sale if anyone is interested.

TB hole is opened to 70mm
Comes with brand new Karcepts t/b adapter plate (the proper one with iacv provision for RRC/RSP manifold use)
Runners have been cleaned up (not hogged out)
Water neck still intact.

$550 shipped within the US.
 

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old post, but still... maybe someone is doing something with RSP intake manifold as did i :D


ps. i'll share results here too,prolly in a few months.
 

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Arouse the DAMPFHAMMER!
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old post, but still... maybe someone is doing something with RSP intake manifold as did i :D
ps. i'll share results here too,prolly in a few months.
Hello muzzle, very good work on that K20Z4 IM. The stock bell mouthes have an flow restriction because of their flow-wise sharp intake edge. A radius of around 5-7 mm or an ellipsed shape of similar size would be better to increase the Flow efficiency. The issue here is, the inflow shape has an bigger effect on the flow efficiency of the runner itself. Therefore I used a elliptical bell mouth shape for my prototyped IM.

I am looking forward to your results. Mine (finalization) will wait till mid of the year, but we saw already around 122 Nm/[email protected] rpm at VTC = 20° and 20° ign. timing, which is far from VE optimum, before the gearbox broke on the dyno.
 

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Looks good I am thinking of doing the same I am currently running that manifold on the k24a3 complete motor with RBB head

Sent from my EML-L29 using Tapatalk
 

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Gilbert, how do you like the RSP? what manifold were you using before that?
Hey howzit always been using this manifold actually, it came with the fn2 model with the original K20z4 motor it comes with

Sent from my EML-L29 using Tapatalk
 
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