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Discussion Starter #83
No. Its no secret. Just havent tried it yet. Unfortunally had som coolantleakage from the head, so ordered a 4piston ported TSX head instead. Gonna instqll that before I change the header.
 

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Arouse the DAMPFHAMMER!
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No. Its no secret. Just havent tried it yet. Unfortunally had som coolantleakage from the head, so ordered a 4piston ported TSX head instead. Gonna instqll that before I change the header.
Sorry to hear that with the head. The 4P TSX has a totally different torque support approach in mind. Turning all measurements before into a different light. That means we will never know what zof484's header will do on an independent test setup. Except you will test your previous header vs. the other one back to back.

Would be kind of you if you measure the 4P TSX exhaust port in height and width at flange level and if possible the throat diameter. My analysis says the head exhaust port efficiency is unbelievable high for stock cross sections, they must have widened it significantly. In my actual view the 4P TSX is for race applications, as for my assumption the exhaust port lowers low end torque significantly and comes alive later on.
 

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Discussion Starter #85 (Edited)
Is the difference so big between the Portflow ported 322cfm PRB vs 4piston ported 327cfm rbb head?!?


This is gonna be back to back testing the new head!:nod:

Then, AFTER testing the new head on the dyno Im switching to Zof’s header and test that vs PLM/Ebaycrap header.

Yes, Ill do my best to get the meausurement for you Marcus!
 

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Arouse the DAMPFHAMMER!
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Is the difference so big between the Portflow ported 322cfm PRB vs 4piston ported 327cfm rbb head?!?
I didn't mean the intake port, I meant the exhaust port which shows flow improvements on 0.5" of around 58 cfm. A increase of around 25 %.

This is gonna be back to back testing the new head!...Then, AFTER testing the new head on the dyno Im switching to Zof’s header and test that vs PLM/Ebaycrap header. Yes, Ill do my best to get the meausurement for you Marcus!
:heart:
 

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Discussion Starter #87
Finally the 4piston head arrived!

Markus you have email!
 

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Arouse the DAMPFHAMMER!
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...I will dive into it in the evening.
The calculations, assumed shape makes it not to precise, resulted in an increased port cross section of 15 %, so the increased flow also comes from improved flow coefficient, which goes linear into the pressure drop calculation. The last one shows an improvement of the flow coefficient of 20 % (91 m/s vs. 83 m/s). What does this mean for the engine operation?
  1. port diffuser angle is bigger (bad) but maybe the header inlet get matched better (good)
  2. pressure drop over exhaust port is after ex valve opening 15-90 times higher than that what is used at the flow bench. At least 90 % of valve opening duration the velocities of stock and 4P TSX port is the same as Mach 1 is reached at the port throat. So if throat is not increased, massflow is the same during that time. After the throat the diffuser angle plays a huge role as well as the step in the ID of header and port in terms of velocity into the header. Here we need higher velocity for a higher impulse formation...not sure how big your engines header port step is...?
  3. Normally exhaust port work is necessary at K-series when you have more displacement, more fuel by lower AFR stoichiometric e.g. Nitromethan, Hydrazin, or similar, or engine speed increases significantly (e.g. 11,500 rpm)...but it is needed at the throat, which changes the valve throat ratio...a sensitive parameter for flow.
I am curious how the port match is in your case in horizontal and vertical direction. K-series header flange is an issue, it reduces port match potential by the thermal expansion, which is unknown...
 

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Why everybody goes 4piston? For sure I would go a different route.
That head does not look so nice to me right below the seat. Somehow the marketing pics are a lot better than this one.
I hope it will perform as good as you expect it.
 

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4 pistons for value and consistency. Much cheaper than most hand ported cylinder head and they're all the same proven design because they're cnc machined which would really hard to duplicate every time if it was hand ported
 

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Arouse the DAMPFHAMMER!
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Why everybody goes 4piston? For sure I would go a different route.
That for reason. Once I ordered a 4P 156 head, which was one of the worst made head I've ever seen...may I seen to less :wink:. Way beyond that what is advertised. User zof484 did it test back to back on a 2000 ccm engine vs a ported or port added high impuls head. As a result the 4P head was around 10 hp back the head, which had the different approach, not cutted for bench flow, added material for higher air impulse.

K24: https://www.k20a.org/forum/showpost.php?p=1976594&postcount=28
K20: https://www.k20a.org/forum/showpost.php?p=1976825&postcount=29

4 pistons for value and consistency.
Should it systemically. The only head porter which comes in my mind when quality meets performance over the years: ENDYN. Larry has a huge know how beside those drag engines...which respond very good to huge ports because impulse comes from 106-108 mm stroke engines. I saw K-series engines with 650 whp on Hydrazin fuel (NA). 1/4 miles aren't the right measurement to say one can port heads. The guy which can produce a port which can have a low flow of a stock head on a 0.92 valve-throat ratio, that one really knows how to get a port flowing. I saw only one guy pushing that limit there: ENDYN.
 

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Arouse the DAMPFHAMMER!
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The 0.92 VTR head with 35 mm intake ports: https://www.facebook.com/energydynamics/posts/2221223281239288

Why is it impressing? The port throat represents the smallest ID of the port and has an huge effect on the port limits concerning flow when valve lift is high and also when valve lift is low. Huge throats are good for the first but mostly loss on the low end side, because the acceleration of air is restricted by the huge throat -> bigger throat lowers the max. velocity which is gonna produced, a smaller throat helps to increase that velocity so that the low lift flow has more impulse = a higher flow. This equals to e.g. a better cam, just by changing no other part than the port and results in a improved torque curve all over the engine speed range!

What Larry did was improving the low lift flow by improving the flow coefficient of the short turn radius, which is part of his Canoda technology. His approach to do own castings is a great chance to get this even more improved.
 

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That for reason. Once I ordered a 4P 156 head, which was one of the worst made head I've ever seen...may I seen to less :wink:. Way beyond that what is advertised. User zof484 did it test back to back on a 2000 ccm engine vs a ported or port added high impuls head. As a result the 4P head was around 10 hp back the head, which had the different approach, not cutted for bench flow, added material for higher air impulse.

K24: https://www.k20a.org/forum/showpost.php?p=1976594&postcount=28
K20: https://www.k20a.org/forum/showpost.php?p=1976825&postcount=29

Should it systemically. The only head porter which comes in my mind when quality meets performance over the years: ENDYN. Larry has a huge know how beside those drag engines...which respond very good to huge ports because impulse comes from 106-108 mm stroke engines. I saw K-series engines with 650 whp on Hydrazin fuel (NA). 1/4 miles aren't the right measurement to say one can port heads. The guy which can produce a port which can have a low flow of a stock head on a 0.92 valve-throat ratio, that one really knows how to get a port flowing. I saw only one guy pushing that limit there: ENDYN.
The US is the leader in K series development but unfortunately the focus is on the drag scene. ENDYN is one of the few well established shops that actively support circuit racing where a wider powerband is needed and developing port designs specifically for this purpose. Its the same for US based cam manufacturers. The circuit racers using their products tend to use the "least aggressive" offerings from these companies as a compromise, although they still peaky in power delivery

Sent from my G8141 using Tapatalk
 

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Arouse the DAMPFHAMMER!
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...ENDYN is one of the few well established shops that actively support circuit racing where a wider powerband is needed and developing port designs specifically for this purpose.
I am not taking up the cudgels for 4Piston, but they do support the circuit racers with their cylinder head program from the 86x86 up to 90x99 engines. Anyway I wouldn't buy one of their crate engines for exact the above mentioned reason, not my engine design concept I would like to follow in a circuit engine.
 

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I am not taking up the cudgels for 4Piston, but they do support the circuit racers with their cylinder head program from the 86x86 up to 90x99 engines. Anyway I wouldn't buy one of their crate engines for exact the above mentioned reason, not my engine design concept I would like to follow in a circuit engine.
Their focus definitely lies with Drag Racing though, this is my point. Even on their website they place emphasis on drag racing achievements, very little mention of teams such as James Houghton's ITR and even then that car runs their Pro TSX which is their least aggressive offering. Interestingly that car used the DC Drop In Cam as well, rather than any of the FI specific cams available from many of the US manufacturers and still produces around 800whp. It's clear that they have selected the parts which they feel gives them the most area under the curve.

Not knocking anyone down, the Drag Racing market is huge in the US and thus the demand is being met by US companies. It's just an observation from my side
 
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