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Discussion Starter #1
Hi K20a folks.

Some of you might remember me, Riku from Finland, driving with K20 powered Toyota MR2 in Finnish Rallycross serie.

You might have seen my build thread:
http://www.k20a.org/forum/showthread.php?t=82729

Thread is missing some of the images which can be found in website gallery:
http://www.hrmotorsport.fi

I've done some Kinsler vs Joe 9.0 testing with ZOF too:
http://www.k20a.org/forum/showthread.php?t=121105&page=49
https://www.youtube.com/watch?v=JBo0-DYpVQs&&feature=related

Ok, back to the topic.

The following quote is taken from HRmotorsport facebook site:
https://www.facebook.com/pages/HRmotorsport/284165204968259

"Hi fans! Check out this EPIC battle!

We are constantly developing our race car. Sometimes we just try to improve it, sometimes updates must be done due to rule regulations.

This time, we are having an epic battle with Andrei "The Mega" zof484 and Riku. Which one is able to produce a better header? :)

Well, it's not that serious, we share ideas and parts for testing :) The 3 right most headers are done by Riku and all the megas have came from zof. The leftmost header is a new addition from zof. This was specially made for this car to allow an easy test of different "secondaries", collectors etc.

Headers in the image are just a small portion of all headers we have tested. We have mostly tested our handmade headers, as they give better results and fit to chassis better. Let's see if we are able to get any gain with this new setup :)"





I thought you might be interested to see what's going on here Finland, and how we are trying to improve our setups.
 

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Mind sharing current engine set up or parts used? 10hp is a good gain.
I would imagine you are around 310 to 320 hp range?
thanks
 

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Discussion Starter #8
Hi,

Ok, so we tested 3 headers. First one having 45mm pipe size, 4-1 model. That was my reference header, which gave ~280hp/240Nm.

Second test was with 45-51mm stepped header, 4-1 model and actually was the header which I ended up using. It gave ~295hp/240Nm. The image attached shows the difference for before and after.

Third one was the testing header made by ZOF, 48-51mm 4-1 stepped header. It came out of the car's trunk so that changing pipes, collectors etc. would be as easy as possible. We ended up adding 10cm extensions to this header and got the best result out of it, which was a bit lower than 45-51mm stepped header.

These test made me ponder, perhaps, next test will be done with 41-45-48mm stepped header, or additionally 45-48-51mm header, as 48-51mm seems a bit too big.

The torque is so low due to rule regulations that came this year. I had to insert a plenum and choke into intake side which loses about 10-15Nm.

This engine has epoxy filled intake ports, Kinsler 60mm ITB, DC4 cams, 13SCR, I think that's the most important stuff to know.

I added a track test video to:HRmotorsport facebook site.

11713539_10206503053231083_161964562_n (1).jpg
 

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Arouse the DAMPFHAMMER!
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Hi you both,

really interesting competition :D

First one having 45mm pipe size, 4-1 model. ...~280hp/240Nm.
Second test was with 45-51mm stepped header, 4-1 model~295hp/240Nm.
What happend at that strange torque decline at about 8.2 to 8.6 krpm? Does fuel, or ignition, or VTC or any other power relevant parameter react also that strangely?

Is there any use to have more mid range torque with the blue torque line setup at that specific racing series? There is a valuable technique to lift it up there without significant loss in the high end...
 

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Discussion Starter #10 (Edited)
Hi you both,

really interesting competition :D


What happend at that strange torque decline at about 8.2 to 8.6 krpm? Does fuel, or ignition, or VTC or any other power relevant parameter react also that strangely?

Is there any use to have more mid range torque with the blue torque line setup at that specific racing series? There is a valuable technique to lift it up there without significant loss in the high end...
Hi,

Hmm, you mean the yellowish line, the lower hp line? I think that was related to the intake restrictions and pulse tuning probably. I didn't see any remarkable variation in ECU logs.

Well, if you check the test video from HRmotorsport facebook site, you can see that there are many types of corners and different track surfaces. The tight corner having tarmac sometimes requires more mid range power to get car quickly out of the corner, hence the mid range power is also important.

The epoxy head and not too big header, proper intake pulse tuning etc. improve the mid range power without losing the top end. Especially epoxy head is something that differs to U.S "tuning". CNC porting is not the proper way to go when A/F mixture needs to get high velocity also at lower RPM.

But as a response to your question: Well, trying to find a bit smaller stepped header combination, might still give better results. And losing a few hp from the very top RPM 9k above, does not matter that much if torque can be improved 10Nm in the mid range, as then you can just use the bigger gears and shift earlier. It would also make the car last longer.

Currently the redline is at 9,5k.

ZOF made a good header, but it just seems that my car likes a bit smaller one. Some good 4-2-1 header combination would be worth of testing too.
 

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Any chance you could give approximate length of headers from flange to the Venturi/choke? Also what are the header choke/Venturi size? 54, 57, 60mm?
 

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Discussion Starter #13
What is your setup of the engine?
Hi LotusElise, what do you want to know? I gave short engine setup info couple of posts ago. I could add to that setup also:

This engine has epoxy filled intake ports, Kinsler 60mm ITB, DC4 cams, 13SCR

+ filled head chambers, +1mm intake valves, modified off-the-shelf 12.4 wisecos to fit into modified chambers. F20C oil pump and many other small updates.

I have tuned Kinslers for 2nd harmonics ~9k.

About the header.
I have seen that in most cases about 680-700mm long primaries give the best power range.

Current header runs 45mm-to-51mm stepped header model. The header in dyno video had 48mm-to-51mm steps and 51mm choke between collector and mega. But I should do a few more tests with bigger mega entrance, if 51mm choke is too small.
 

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Arouse the DAMPFHAMMER!
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Hmm, you mean the yellowish line, the lower hp line? I think that was related to the intake restrictions and pulse tuning probably. I didn't see any remarkable variation in ECU logs.
Thanks for your replay. Yes, I meant the yellow (my screen shows a orange one :D) power and green torque line.

I was just curious about it, as I wasn't aware of pressure wave timing issues at that engine speed area of 8.0-8.5 krpm wouldn't affect those of 8.5-9.5 krpm in that way.
...Especially epoxy head is something that differs to U.S "tuning". ...
Both, increasing the volume flow (unit: cfm) and increasing the volume flow rate (unit: m/s) are valuables ways to go. Best is to do a compromise of both as the engine needs both: high VE and high turbulence for a high combustion rate. And I totally agree with you that the second way helps a bit more to support the midrange via the higher impulse intensity of the pressure wave. But I was thinking of a further technique...curious why the K-world didn't use it already :confuesed:

...trying to find a bit smaller stepped header combination, might still give better results...
...yes, but...
...losing a few hp from the very top RPM 9k above...
...isn't necessary.
...torque can be improved 10Nm in the mid range, as then you can just use the bigger gears and shift earlier. It would also make the car last longer...
...yes, I like that way :D! Just increasing the BMEP from midrange till top end via Natural Forced Induction (NFI tuning), I don't know a better phrase for VE and cumbustion chamber turbulence tuning for a broad engine speed range of a high speed engine concept :D.
 

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Discussion Starter #15 (Edited)
Thanks for your replay. Yes, I meant the yellow (my screen shows a orange one :D) power and green torque line.

I was just curious about it, as I wasn't aware of pressure wave timing issues at that engine speed area of 8.0-8.5 krpm wouldn't affect those of 8.5-9.5 krpm in that way.
Well, yes, at least in this case. I believe, it relates to plenum + choke in the plenum. I didn't have this drop before without the plenum. And yes, I know, I should build another plenum, which would work even better.

Both, increasing the volume flow (unit: cfm) and increasing the volume flow rate (unit: m/s) are valuables ways to go. Best is to do a compromise of both as the engine needs both: high VE and high turbulence for a high combustion rate. And I totally agree with you that the second way helps a bit more to support the midrange via the higher impulse intensity of the pressure wave. But I was thinking of a further technique...curious why the K-world didn't use it already :confuesed:
What is your further technique, or did I understood wrong?
Yes, it's interesting that they don't see it that way. Keeping the velocity as high as possible, provides good BMEP/cylinder fill even with lower RPM. It's all about physics, the air/fuel mixture has mass, when mass is accelerated via smaller port it get's higher speed. When pistons starts to move upwards from BDC, the mixture still has high velocity, it will fill the cylinder even though piston moves upwards. We need to dimension the port for certain max. power, so that velocity does not get too high at peak power.

But yeah, K-world as well as this forum is mostly filled with guys from US. And in US, they have these big Honda tuning companies, which like to use CNC machines and make the finishing for the head, but not actually make the serious tuning/improvements which would require a bit more work, I think. Original ports are too big already, ofc. they work for car running 10k RPM, but not much for the lower RPM. And I haven't seen any video, which would have transmission with proper gear ratios, which would take the benefit of narrow power band around 10k. Therefore it wouldn't harm if engine would have broader power band.

Check out the page for GearMotive. I'm building dog box transmissions for race cars, like my own car. During the next winter we are building a new 6 speed dogbox kit for Honda, which is strong, works and has proper gear ratios.

...yes, but...

...isn't necessary.

...yes, I like that way :D! Just increasing the BMEP from midrange till top end via Natural Forced Induction (NFI tuning), I don't know a better phrase for VE and cumbustion chamber turbulence tuning for a broad engine speed range of a high speed engine concept :D.
Yep, quite much true. When dimensions are correct, it shouldn't cut from the top end, but still providing good mid range. Finding that setup would require building yet another header :)
 

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Arouse the DAMPFHAMMER!
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Hi ukir85,

thanks for your response...quite interessting :D.

...This engine has epoxy filled intake ports + filled head chambers, +1mm intake valves, modified off-the-shelf 12.4 wisecos to fit into modified chambers...
Is this one the cylinder head of Andre Norrback? I still think about it, I like that idea. In addition I see still some room to squeeze out more ponies in terms of accelerate the combustion to advance the knock margin and to gain more areas of be able to reach MBT (mean best torque), especially when the CR increases over 12:1. Did you ever work in that direction?


...Kinsler 60mm ITB...tuned...for 2nd harmonics ~9k
Did you test smaller runner diameters too? My theoretical examination shows quite peaky VE behaviour with an ID of 60 mm (like the green torque line), especially when they get into efficient length areas. My new plenum intake manifold maybe will point out what it could be :D...need some time to fabricate :scared:.

...680-700mm long primaries...45mm-to-51mm...51mm choke...
The Jack Burns 4-1 headers are also in that range of lenght, but had two steps from 48-51-54 mm, they where the reference when Joe once started his 4-2-1 development. I like the 4-2-1 design more, as it has a greater flexibility for torque forming. I am in discussions with a header builder to fab my best 4-2-1 design, which uses two different technologies to broaden the area of high VE's at WOT. Maybe there is once a chance to compare :D.

...I didn't have this drop before without the plenum.
The blue torque line didn't show that dip. Wasn't it the same plenum?

What is your further technique, or did I understood wrong?
I will present it once I will have tested it on the dyno...

...Keeping the velocity as high as possible, provides good BMEP/cylinder fill even with lower RPM.
Yes, because of two effects, #1 is...
...When pistons starts to move upwards from BDC, the mixture still has high velocity, it will fill the cylinder even though piston moves upwards.
...at the right time of the pressure wave in addition :up:. The higher the valve duration, the more of that effect is needed to get a efficient dynamic compression. And #2 is the tumble in the combustion chamber is increased which helps to get low combustion durations and therefore a better torque (higher cylinder peak pressure without higher knock probability). I think that field is still low developed (maybe except EDYN pistons, just talked with Larry about it but never saw it)

Check out the page for GearMotive.
will read it :up:

Finding that setup would require building yet another header :)
I was talking with zof484 about that and exchanged some design proposals which are near to Joe's design...the design which out performs Joe's 4-2-1 design (for now only in the simulation :D) I didn't share, as I want to test it first...but to compare it with those of you both would be funny :D
 

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Arouse the DAMPFHAMMER!
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Link didn't work...is the hompage temporarly down or just released soon? Appreciate your answer, as I am curious :D

Edit, 14.07.2015: Link works fine :up:, was probably an issue with the add on management.
 

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Discussion Starter #18
Link didn't work...is the hompage temporarly down or just released soon? Appreciate your answer, as I am curious :D
Really, should work:

gearmotive.com , try without www in the beginning.
The page is quite new anyways and does not have all the content yet.

I will reply later to your previous post.
 

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Arouse the DAMPFHAMMER!
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...gearmotive.com , try without www in the beginning.
I did, I also did check search engines too. Only Google translator could load it, maybe it's a browser issue. Is it browser specific for now? I will try an another tomorrow...anyway, thanks for your quike response.
 

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Discussion Starter #20
Hi ukir85,

thanks for your response...quite interessting :D.


Is this one the cylinder head of Andre Norrback? I still think about it, I like that idea. In addition I see still some room to squeeze out more ponies in terms of accelerate the combustion to advance the knock margin and to gain more areas of be able to reach MBT (mean best torque), especially when the CR increases over 12:1. Did you ever work in that direction?
Yes, it's made by Andre, but not the head in the image. Hmm. I'm not sure if there's much more to do to improve MBT? Well, ofc. lifting ports higher etc. would help.

Sorry, could you specify, in which direction?


Did you test smaller runner diameters too? My theoretical examination shows quite peaky VE behaviour with an ID of 60 mm (like the green torque line), especially when they get into efficient length areas. My new plenum intake manifold maybe will point out what it could be :D...need some time to fabricate :scared:.
Yes, I had 51mm earlier. The 60mm gave the better top end and actually made the curve more stable. Your manifold work sounds interesting. Do you have any info anywhere. The problem with Joe's manifold is that it loses torque in comparison to ITB. Now I have the same problem, as I had to build the plenum on top of ITB, it loses torque. I hope you could find an answer/solution to that problem, but I don't know if there is any. Secondly, I can't understand by physical means, why the plenum loses torque, but not the top end power, would you have explanation for that?

The blue torque line didn't show that dip. Wasn't it the same plenum?

I will present it once I will have tested it on the dyno...
Yes, they were having the same plenum, but ofc. better ex. tuning affects also on intake side during overlap etc.

#2 is the tumble in the combustion chamber is increased which helps to get low combustion durations and therefore a better torque (higher cylinder peak pressure without higher knock probability). I think that field is still low developed (maybe except EDYN pistons, just talked with Larry about it but never saw it)
Hmm. this is also what we aimed during this build up. Filling the chambers, trying to keep pistons dome low, valve pockets area open etc. It would be interesting to test a piston having a big pit in the middle of dome.

I was talking with zof484 about that and exchanged some design proposals which are near to Joe's design...the design which out performs Joe's 4-2-1 design (for now only in the simulation :D) I didn't share, as I want to test it first...but to compare it with those of you both would be funny :D
[/QUOTE]

Yep, definitely.
 
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