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Arouse the DAMPFHAMMER!
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Please see red above.
Thanks man :).

Nope, I got a great deal off one of the Facebook forums BNIB that I couldn't pass up. Do i think the engine might be slightly overcammed?
I just thought so, because I believe with a bit less duration and more important around 1.5 mm less of intake and around 1.0 mm of exhaust valve lift your VE production could be better than with this huge race cam. You can see an indication of that as even the pumping and friction losses increases quadratic the torque still tends to fall just linear beyond the peak VE of the RRC IM.

I am not saying it is a bad cam, I just want to point out there are maybe 5-10 ftlb's in the midrange just sleeping, and there, where those cams began the storm, the engine breathing chokes more or less and restrict a better performance...

I would be interested in the valvetrain noise of those. Do you have any video of the idle of it, I would appreciate it. The 4Piston cams, produced by Webcamshaft.com, are real race cams with very stiff opening ramps, producing a good VE-level. The backside of that is the timing chain tensioner and the chain itself are operating under higher load. For a racing engine it doesn't mind (except some circuit racers here in Europe, which sold them because of increasing maintenance costs and reliability), for an DD it will be a mess if those critical parts don't get checked in shorter intervalls.

The fuel setup starts at the pump > filter > rail > FPR > return to tank. I did not want a dead rail set up.
My fault, I just couldn't see it in the picture, I still just can see a dead end fuel rail. Seems to be my eyes need to go to bed for recovery :D.

After reading several threads here, almost everyone with a 2.4 has made more power changing to a larger diameter intake.
Yes, a 3.5" set could help to open the bottleneck a bit in the high end, but you likely will loose some low end and midrange ponies. Is peak power the only value you are searching for?

Markus
 

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Thanks man :)
I just thought so, because I believe with a bit less duration and more important around 1.5 mm less of intake and around 1.0 mm of exhaust valve lift your VE production could be better than with this huge race cam. You can see an indication of that as even the pumping and friction losses increases quadratic the torque still tends to fall just linear beyond the peak VE of the RRC IM.

I am not saying it is a bad cam, I just want to point out there are maybe 5-10 ftlb's in the midrange just sleeping, and there, where those cams began the storm, the engine breathing chokes more or less and restrict a better performance...
Proves my assumption correct. I knew I was bit overcammed, but for the price point it wasn't something I could have 'not' purchased. Down the road I plan to port the head and get ITBs, which will help. As it stands right now, I genuinely don't think I would even notice the 'sleeping' 5ftlb to justify a cam change or spending the money to do so.

I would be interested in the valvetrain noise of those. Do you have any video of the idle of it, I would appreciate it. The 4Piston cams, produced by Webcamshaft.com, are real race cams with very stiff opening ramps, producing a good VE-level. The backside of that is the timing chain tensioner and the chain itself are operating under higher load. For a racing engine it doesn't mind (except some circuit racers here in Europe, which sold them because of increasing maintenance costs and reliability), for an DD it will be a mess if those critical parts don't get checked in shorter intervalls.
Good thing it's not a DD! Car idles quiet (for what it is) and smoothly, unfortunately no videos and it's put away for the winter.


Yes, a 3.5" set could help to open the bottleneck a bit in the high end, but you likely will loose some low end and midrange ponies. Is peak power the only value you are searching for?
If I was, I would have never admitted the engine was overcammed lol.

Thanks for your input dude!
 

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Hey Markus.
Do you have time to explain a little bit about the affect for an overcammed & undercammed for a road race car? Is it mainly just the mid range torque?
 

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Arouse the DAMPFHAMMER!
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...Down the road I plan to port the head and get ITBs, which will help. As it stands right now, I genuinely don't think I would even notice the 'sleeping' 5ftlb to justify a cam change...
Understood, your setup is still ready for harmonization of parts :up:

Good thing it's not a DD! Car idles quiet (for what it is) and smoothly, unfortunately no videos and it's put away for the winter.
So no harder valvetrain noise or slacking timing chain?

Webcamshaft.com has huge and longterm experience in Camshaft design of nearly all applications, so no doubt on the quality, but from the spec data and from the experience of some racers those cams come not only with great VE but also high wear on valvetrain parts. Great for racers who open there engines for maintenance frequently :D

Do you have time to explain a little bit about the affect for an overcammed & undercammed for a road race car? Is it mainly just the mid range torque?
I don't know where this wording comes from (non-native speaker) as it there is no exact definition of it in literature. What is understood with over- or undercammed most is the match of the engine setup with the cam.

Undercammed would be the situation the choosen camshaft support the engine VE best below or only left handed partly of the wished engine speed bandwidth, e.g. a ITR cam for a racing engine (CR = 13:1, ported head, ITB's, 4-1 short header, 3", ...). It is characterized by the engine setup supports the area of 6000-9000 rpm while the cam supports by design the area form 4000-7000 rpm, this mismatch could be seen in a higher level of 2nd bandwidth (4-7 krpm) and a strong declining torque of the 1st bandwidth (6-9 krpm)

Overcammed is the opposite around. The effect in the torque line is always the same, both situations prevent the engine to release it's overall potential VE- or torque-wise. Consequently all parts of the engine setup need to be harmonized in some way for the aimed application. It does not only mean all parts are designed for peak power, it could also be like I do it with my project, all parts are designed to support engine VE over a 4000 rpm wide high level VE bandwidth.

Another point to mention, If I would list up my parts list of the longblock and list also the aimed torque line everyone would say it's a undercammed engine. But I would state this only by seeing the engine setup list and the dyno result in combination.

Markus
 

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Understood, your setup is still ready for harmonization of parts :up:

So no harder valvetrain noise or slacking timing chain?

Webcamshaft.com has huge and longterm experience in Camshaft design of nearly all applications, so no doubt on the quality, but from the spec data and from the experience of some racers those cams come not only with great VE but also high wear on valvetrain parts. Great for racers who open there engines for maintenance frequently :D
No sir, no more than one would expect from a cammed K series. My brothers old Buddy Club cams used to slap and these are on a completely different ballpark.

And to your point about frequent maintenance, hopefully everyone knows once you swap cams keeping the engine under a watchful eye becomes mandatory. Nothings quite like OEM lol.

Nice. How was valve to piston clearance with k600 and rs machine pistons? Stock headgasket thickness?
I wish I could tell you, I did not measure the P2V clearance. And yes, I am using the OEM headgasket. These pistons were designed to be a larger version of the K20R piston, so they don't have larger valve reliefs like one would see on the Supertechs or any off the shelf forged piston for instance. I limited VTC to 35* on the gear and all is well so far. The engine already has about 3000 miles on it.
 

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274whp/198tq

Engine:
K24A2 Bottom end
12:1 RS Machine Pistons
OEM Rods
RBC-2 Head
Supertech H1021D Valve Train Kit
4Piston K600 Camshafts
RRC Intake Manifold
70MM Hybrid Racing Throttle Body
ASP 4-1 Header, no megaphone
3" Thermal Exhaust
3" Intake

Fuel System:
-6 AN feed/return
AEM FPR
Karcepts Fuel Rail
ID 1000cc Injectors
Walbro 255

Although I'm happy with how it runs, I think the 3" intake might be holding me back some.
what oil pump you running ??? what rpm is your power band ???
 

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274whp/198tq

Engine:
K24A2 Bottom end
12:1 RS Machine Pistons
OEM Rods
RBC-2 Head
Supertech H1021D Valve Train Kit
4Piston K600 Camshafts
RRC Intake Manifold
70MM Hybrid Racing Throttle Body
ASP 4-1 Header, no megaphone
3" Thermal Exhaust
3" Intake

Fuel System:
-6 AN feed/return
AEM FPR
Karcepts Fuel Rail
ID 1000cc Injectors
Walbro 255

Although I'm happy with how it runs, I think the 3" intake might be holding me back some.


What fuel was this on?
 

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Where did you find the RS machine pistons in a bore size large enough for a k24? The maximum I see on their website is 86 mm.
Here is a similar listing to what I purchased on eBay: https://www.ebay.com/itm/192301291960

The engine has a little north of 5k on it and runs very well. No complaints and a little proud of it considering the fact the bottom end was done on a budget.
 

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Accord K24A3 Block
K20A Head with light head work
Stock K20A2 cams
RS Machines Pistons
GE IM, Intake, Ebay Header, 3 inch exhaust
C66 (66% Ethanol)
Tuned with Hondata KPro - Flex Fuel Setup

280 WHP 216 LB/FT
 

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Accord K24A3 Block
K20A Head with light head work
Stock K20A2 cams
RS Machines Pistons
GE IM, Intake, Ebay Header, 3 inch exhaust
C66 (66% Ethanol)
Tuned with Hondata KPro - Flex Fuel Setup

280 WHP 216 LB/FT
What was the comp ratio of the Pistons ? That’s some great power on oem cams!
 
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