Does quench affect power?

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Re: Does quench affect power?

Post by juuhanaa »

Here is a prtsc about interference between R19 and experimental stuff.. Its a pain for me, but i can do roughly something using cars own system. I didn't check or optimize ignition advance with respect to crank position, so that table doesnt have much value for this topic..

ignition BWM evo1.png



Now for a comparison other "flattish piston" in a Renault F4R basis and Motec400. Static CR was restricted by the rules in this old class to 11, intake 4,15 and exhaust 3,5 open @ TDC. Head gasket approx ,6mm. Its difficult to estimate VE based on these info, but the builder told he would have liked to add more CR.

IMG_20220929_160501.jpg
wiseco+ojennus.jpeg
IMG_20210718_164308.jpg
main fuel table.png
main ignition table.png


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Re: Does quench affect power?

Post by LotusElise »

juuhanaa wrote: Thu Sep 29, 2022 3:43 pm Here is a prtsc about interference between R19 and experimental stuff.. Its a pain for me, but i can do roughly something using cars own system. I didn't check or optimize ignition advance with respect to crank position, so that table doesnt have much value for this topic..

Now for a comparison other "flattish piston" in a Renault F4R basis and Motec400. Static CR was restricted by the rules in this old class to 11, intake 4,15 and exhaust 3,5 open @ TDC. Head gasket approx ,6mm. Its difficult to estimate VE based on these info, but the builder told he would have liked to add more CR.
Mmmmhhhh...seems to be different combustion regimes, 7° IGT difference :D.

P.S. why is it pain for you to tune the R19 ECU?
DAMPFHAMMER engine:
2000 ccm, Honda K20 NA engine
4000 rpm bandwidth of at least 192 ftlb
310 hp@8200 rpm
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Re: Does quench affect power?

Post by ptuomov »

LotusElise wrote: Thu Sep 29, 2022 12:59 am The picture is from Larry Widmer's latest K-series head design, can be bought in the aftermarket as Larry sold his stuff to two companies. He built a complete own casted K-series head, amazing stuff and quite a genious idea.
Do they sell matching modern pistons for those aftermarket heads? All of the “old one” web site pistons look like they are artifacts from some archaeological dig from the previous millennium.
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Re: Does quench affect power?

Post by LotusElise »

ptuomov wrote: Fri Sep 30, 2022 10:11 am Do they sell matching modern pistons for those aftermarket heads? All of the “old one” web site pistons look like they are artifacts from some archaeological dig from the previous millennium.
To be diplomatic, those companies who bought Larry's heads and design and it's production work on different approaches. As far I know the CV from Larry he came from the combustion and alternation of load side and the "The Old One" and company was his hobby after his retirement in 2006. The companies, who bought his company, came both from the drag race scene. That is a field of bigger goes better, so the development path is much straight forward then in a circuit engine world. Combustion chamber design is not most urgent task in the drag race scene, they run on Alcohol blends, huge cams and CR's of 14:1 and more as well as crazy rod stroke ratio's of 1.35 and smaller. This are VE driven high engine speed designs, which is no learning field for combustion process design.

Regarding matching, Larry was smart enough to design his heads for after market blocks, no special piston dome adaption needed. The CR calculation of course is changing, same CR = less dome volume compared to stock chamber designs.

Regarding the look like of those pistons. Many ways lead to Rome. And as Larry knew that time quite well what combustion needs I believe his approach was not bad comparing to others. The idea behind the Roller Wave technology is quite simple, is influenced by his fathers background as many of his inventions are and plausible to me. The idea is a squish induced push of the flame front into the chamber area which is hottest to reduce heat flux out of the combustion zone to reduce it's duration. Due to the increase in temperature this asymmetrical flame front propagation speeds up and get reflected on the exhaust "wall", shaped by the exhaust valve relief and liner. The reflected impulse increases now the flame speed on the cold side to. The overall win would be the shorter 0-50 % MFB or so, driven by the exhaust thingy and of course pressure waves moves faster then flame speed, that can increase TKE or bring the mixture nearer to activation energy to oxidize.

As I mentioned, many way lead to Rome. Challenges of former times lead to genius inventions, today's challenges are more spread, manifold and less significant. We are in the upper part of the technology S, the next generation engineers is already laughing about ICE guys, like us. I am in a PEM fuel cell system development, jumped from an engine OEM to hybridization to fuel cell technology. The invention gradient there is like the ICE invention gradient of the 80'ies or 20'ies of the last century. I wouldn't look from today's ICE down to former times, these guys did more for the ICE as we can ever do.
DAMPFHAMMER engine:
2000 ccm, Honda K20 NA engine
4000 rpm bandwidth of at least 192 ftlb
310 hp@8200 rpm
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Re: Does quench affect power?

Post by ptuomov »

I wasn't complaining so much about the piston crown shape on the "old one" site but the rest of the piston looking old fashioned.
Paradigms often shift without the clutch -- https://www.youtube.com/watch?v=cxn-LxwsrnU
https://www.instagram.com/ptuomov/
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Re: Does quench affect power?

Post by juuhanaa »

LotusElise wrote: Fri Sep 30, 2022 10:01 am
juuhanaa wrote: Thu Sep 29, 2022 3:43 pm Here is a prtsc about interference between R19 and experimental stuff.. Its a pain for me, but i can do roughly something using cars own system. I didn't check or optimize ignition advance with respect to crank position, so that table doesnt have much value for this topic..

Now for a comparison other "flattish piston" in a Renault F4R basis and Motec400. Static CR was restricted by the rules in this old class to 11, intake 4,15 and exhaust 3,5 open @ TDC. Head gasket approx ,6mm. Its difficult to estimate VE based on these info, but the builder told he would have liked to add more CR.
Mmmmhhhh...seems to be different combustion regimes, 7° IGT difference :D.

P.S. why is it pain for you to tune the R19 ECU?
It is a pain, because of memories.

My R19 is an old everyday car, that my friend gave it to me and i owe him something.. Anyway it doesn't look like the BTCC R19 below, but please take a look what is written on the back door of that car.

R19.jpg

Its not a pain, because of XDF file is written in French, nor that i got my tube bender waay before my soldering iron.. It is, because when we went racing that car in very first time. I am telling you my crew member, who is a grown Man cried when i handed him the first award..

Imagine it was snowing and we were busy and spend some time on a wheel base setting the car during the event! It had BMW pistons, but it didnt even have headers in it! Later we dyno that engine and after that during track testing it finally threw the rod out, but it made extra noise from start to finish..Thats why and after that, i have been figuring what happened.

IMG_1540.JPG


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Re: Does quench affect power?

Post by juuhanaa »

Mmmmhhhh...seems to be different combustion regimes, 7° IGT difference :D.

Took me like 1.5 Years to figure noise that started at idle, came from my faulty piston pin machining :D

Thats a another thing. It is not enough to get clearance right and round, bushing needs to be straight in relation to the rod #-o Lesson learned, better leave some machining to professionals.

Screenshot_20220930-233845.jpg


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Re: Does quench affect power?

Post by ptuomov »

LotusElise wrote: Tue Sep 27, 2022 3:39 amThat project would be much easier on a wedge head design, but the rigidity, stiffness, precision and capability of the Honda K20 basis is phenomenal. Achieving 370 hp at flywheel below 10,000 rpm on a 2-Liter-I4 engine is something pretty challenging on a NA induction concept, I know no single example. Maybe you guys know one? That not enough, I want to have 1.54 ftlb/cui from 5500-9500 rpm. I've already reached similar with an engine but from 4500-8200 rpm.
LotusElise wrote: Fri Sep 30, 2022 11:06 amTo be diplomatic, those companies who bought Larry's heads and design and it's production work on different approaches. As far I know the CV from Larry he came from the combustion and alternation of load side and the "The Old One" and company was his hobby after his retirement in 2006. The companies, who bought his company, came both from the drag race scene. That is a field of bigger goes better, so the development path is much straight forward then in a circuit engine world. Combustion chamber design is not most urgent task in the drag race scene, they run on Alcohol blends, huge cams and CR's of 14:1 and more as well as crazy rod stroke ratio's of 1.35 and smaller. This are VE driven high engine speed designs, which is no learning field for combustion process design.
If they aftermarket-head drag racing gentlemen are running 14:1 CR, what's chamber volume in their head-piston combo? It seems like they do have to pay a lot of attention to the combustion chamber if they can run 14:1 CR with anything like your stroke with these heads. Or perhaps their stroke is a mile long...

In any case, the combustion chamber in those heads looks good to me for high geometric compression ratio. I can't immediately say that I'd do anything that differently. (The piston will of course then complete the combustion chamber, so that needs to be designed specifically for the chamber and specifically for the cams.)

Since you're looking to make 92.5hp per 500cc cylinder at 10,000rpm, I personally think that you will also have to "go big" as in size everything for that peak power.

Are you running some VTEC version in this engine? That is, can you (a) advance/retard the intake cam on a running engine and (b) switch between two different intake and exhaust lobes? Sorry if this has already been asked and answered. Using two cam profiles and advancing the intake cam selectively will help you get that flat torque curve. As a counter point, you'll have a complex system and potentially larger valve pockets in the piston. One idea might be to size the piston crown valve relief and the high rpm cam for the peak power, then force the (slightly) smaller cam lobe that is advanced and retarded to live inside that valve relief.

Have you considered a continuously variable intake length system? Like this: https://www.roadandtrack.com/car-cultur ... th-intake/
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Re: Does quench affect power?

Post by LotusElise »

juuhanaa wrote: Fri Sep 30, 2022 3:30 pm It is a pain, because of memories.
But good memories finally, aren't those?
DAMPFHAMMER engine:
2000 ccm, Honda K20 NA engine
4000 rpm bandwidth of at least 192 ftlb
310 hp@8200 rpm
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Re: Does quench affect power?

Post by LotusElise »

juuhanaa wrote: Sat Oct 01, 2022 3:13 am Took me like 1.5 Years to figure noise that started at idle, came from my faulty piston pin machining :D
It hold quite long :D. But yes, precise machining is a requirement for optimal operation.
DAMPFHAMMER engine:
2000 ccm, Honda K20 NA engine
4000 rpm bandwidth of at least 192 ftlb
310 hp@8200 rpm
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Posts: 99
Joined: Tue Mar 09, 2021 10:05 am
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Re: Does quench affect power?

Post by LotusElise »

ptuomov wrote: Sat Oct 01, 2022 8:47 pm If they aftermarket-head drag racing gentlemen are running 14:1 CR, what's chamber volume in their head-piston combo?
About 50.5-51.5 ccm. Dome volume looks like the Mount Everest.
ptuomov wrote: Sat Oct 01, 2022 8:47 pmSince you're looking to make 92.5hp per 500cc cylinder at 10,000rpm, I personally think that you will also have to "go big" as in size everything for that peak power.
Actually the plan is to go as small as possible, means the alternation of load need some work to do.
ptuomov wrote: Sat Oct 01, 2022 8:47 pmHave you considered a continuously variable intake length system? Like this: https://www.roadandtrack.com/car-cultur ... th-intake/
That is prohibited by specification. Only intake cam has a phase variability. For the 900 rpm idle requirement, yes, I have to run a full iVTEC system.
DAMPFHAMMER engine:
2000 ccm, Honda K20 NA engine
4000 rpm bandwidth of at least 192 ftlb
310 hp@8200 rpm
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Re: Does quench affect power?

Post by ptuomov »

“Actually the plan is to go as small as possible, means the alternation of load need some work to do.”

As small as possible is still going to be pretty big.
Paradigms often shift without the clutch -- https://www.youtube.com/watch?v=cxn-LxwsrnU
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Re: Does quench affect power?

Post by LotusElise »

ptuomov wrote: Mon Oct 03, 2022 7:41 am As small as possible is still going to be pretty big.
Stock sizes are 35/30 mm on that 4-valve head. Keeping it smallest would mean staying there just to give that qualities a number.
DAMPFHAMMER engine:
2000 ccm, Honda K20 NA engine
4000 rpm bandwidth of at least 192 ftlb
310 hp@8200 rpm
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Re: Does quench affect power?

Post by ptuomov »

Why not put in the biggest intake valves that fit and aren’t shrouded and then keep the port small at valve guides?
Paradigms often shift without the clutch -- https://www.youtube.com/watch?v=cxn-LxwsrnU
https://www.instagram.com/ptuomov/
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Re: Does quench affect power?

Post by LotusElise »

ptuomov wrote: Wed Oct 05, 2022 12:15 pm Why not put in the biggest intake valves that fit and aren’t shrouded and then keep the port small at valve guides?
The biggest unshrouded would be around 33 mm at intake and around 28 mm at exhaust. That 4-valve head has shrouded areas already from OEM status on. May we define how much shrouding still improves flow to find the optimum for the application? I assume this is very engine and application specific #-o.
DAMPFHAMMER engine:
2000 ccm, Honda K20 NA engine
4000 rpm bandwidth of at least 192 ftlb
310 hp@8200 rpm
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