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1. Extensively track tested junkyard K24A2 at 8200rpm with production kit on track with zero issues. Known data point. I have no direct personal experience here.
2. We are building an 8800rpm K20A2 with big cams with altered oiling system, which almost no one on this forum has direct personal experience with.
It's hard to convey just how deep Hytech's knowledge and experience goes here. The F20 has a very short pick up tube, zero oiling issues. The K series have a longer pick up tube which is in part responsible for the oiling issues seen in road racing K series motors with higher rev limits. Again, not to be confused with lower revving stock K24 that never see 8300 let alone 8800 or drag motors that see less than one minute a year at peak revs or sustained 1.5G loads. John happens to know the US engineer that designed the oil pump gears for Honda for the K20. He describes the inherent limitations of the system and how Honda was quite aware of them. Note that the K20 oil pump rotors are significantly larger than F20 rotors. This is in part, to increase volume to cope with the flow restrictions of the K's longer pick up tube. There is a limit to how large the gears can be and still retain a high rev limit. There are other factors that affect oiling system integrity and function at high rpm, all of which are addressed in the vaccuum pump system we built. John has also done very careful flow studies/experimentation of the entire oiling system and built a few hundred K20's. He supplies an overseas road racing series with K20's with heavily revised oiling systems as his prior experience with a US customer engines indicated. Some of those were 700whp 10k rpm drag motors you speak of. He regularly does consulting, R&D and custom fabrication work for Honda. To say he knows how K20's work better than most tuners is an understatement. Our other source was Doug at Hondata. Again, a guy that eat sleeps and breathes high rpm, crazy high power K series race engines.
So, I chose to take the steps I'm taking based on what I believe to be expert advice. If you are reading this, you should also do your own research and draw your own conclusions.
Current state of build. Engine done. Vacuum pump oiling system and custom alumimum oil pan done. Intake manifold is a one off. Getting tumbled so it will look pretty. TB mounts in the center of the plenum and faces down. Best possible flow. Valve cover is powder coated orange. It has been at Hytech for about 10 months. Its here this week to get some wiring harness stuff started.
I would guess we still have about 80-100 hrs left on it.
Current state of build. Engine done. Vacuum pump oiling system and custom alumimum oil pan done. Intake manifold is a one off. Getting tumbled so it will look pretty. TB mounts in the center of the plenum and faces down. Best possible flow. Valve cover is powder coated orange. It has been at Hytech for about 10 months. Its here this week to get some wiring harness stuff started.
I would guess we still have about 80-100 hrs left on it.
You know once you drive this thing your never going to be able to go back to a BP, it's like watching a top fuel car, nothing else ever looks fast.
Interesting coolant routing choice. Keep all the hot stuff on the one side of the motor. I may copy that at some point.
And yes, center-feed is the way to go on a K-series. Is John building it from scratch? Or starting with something existing? I was looking into having Lance Hayward do one for me. Plenty of room for activities in that side of the engine bay. Plus, it makes finding cold air easier.
Edit => Was reviewing the thread and came across this pic...and I recognize that logo! Great minds think alike.
Last edited by AndyHollis; 12-15-2015 at 08:26 AM.
Interesting coolant routing choice. Keep all the hot stuff on the one side of the motor. I may copy that at some point.
And yes, center-feed is the way to go on a K-series. Is John building it from scratch? Or starting with something existing? I was looking into having Lance Hayward do one for me. Plenty of room for activities in that side of the engine bay. Plus, it makes finding cold air easier.
Edit => Was reviewing the thread and came across this pic...and I recognize that logo! Great minds think alike.
It's built with the Hayward Performance components you see but with several customizations. Injector bosses are on the runners about 80mm up and aimed directly at valves. He consulted with a few other top K series tuners on injector placement and settled on that exact spot. TB location, runners ported, port matched, velocity stacks built into plenum, etc.
Original plan was a modified RRC. John had the Hayward parts laying around and though he could get more power from them with a center feed setup.
I talked with him about intake pipe length and shared how the testing we had done with BP's indicated a shallow bell curve of power levels with varying pipe lengths, 21" being the sweet spot. He had the same data for the K, only the "top of the bell curve" length was a bit longer at around 24". So we laid out a route for a 24" pipe that terminates up by the clutch master. Being cold side, we won't bother making an enclosure for it.
John had the Hayward parts laying around and though he could get more power from them with a center feed setup.
Can't wait to see what you end up with there
So we laid out a route for a 24" pipe that terminates up by the clutch master. Being cold side, we won't bother making an enclosure for it.
I hope you have better luck than I did with that location. It's cold-side, but that motor generates a LOT of heat, especially with the header primaries coiled up in there (yours is better than mine in that regard, though).
Speaking of header heat...any thoughts of a heat shield, coating, wrap, or sectioning it off? After I get my hood venting done (Thanks Ryan!), I'll probably do something with the header itself.
Just for reference, the K20 I built for autocross use in the CRX made 250 at the wheels (Dynojet STD). 13:1, ported TSX head, Kelford B2 & springs, RRC intake/70mm TB, Hytech header, E85. Pretty simple build with off-the-shelf parts. That's the same header John built for me six years ago. Still running strong!
I will have the header coated. We do that on all the racecars here to help keep the drivers floor from heating up so much. Shame, as it is so pretty but yeah it's going to melt all kinds of stuff otherwise.
We sorta did. It has an external vacuum pump. Stock oil pump assembly is gone. The prime concern is with the pickup tube of the K series. That tube is at the core of the K series oiling issues. Some of you know basic formulas for determining flow loss through a tube. The K series plot rolls off then has a knee point where it drops to nil. That corresponds to a specific RPM with the stock gears, slightly higher with a blueprinted/ported pump. John knows the American specialist that designed the oil pump gears for Honda on the K20. The F20C pick up tubs is less than half the length so it doesn't have the issue the K series does. The kit lengthens the K series tube significantly. At lower revs, this can be made to work. At high revs, it will not. This part is not conjecture but something Hytech as a bunch of data on.
So we no have no pick up tube per se. Two separate dry sump style pick ups in a single main sump. That sump is located where the exhaust pass through was.
In the end, it's the time consuming expensive way to address high rpm K series oiling issues in a Miata. The standard kit would be far less attractive to folks if it had been designed like ours. But then most folks will put a K24 in and keep revs under whatever Kmiata tells you.
^^^ Came across this today...looks like John is not the only one offering this type of oiling solution for tracked high-revving K20's...or maybe he was the first and others followed? Pics and diagram are useful for the discussion.
One question I have is oiling of the timing chain...how does that work? Normally it gets splash-fed from below with the oil pump. I know there's a small bleed feed through the tensioner plunger, so maybe that is enough? Or drip-down from the valve cover area?
Last edited by AndyHollis; 12-30-2015 at 08:34 AM.
^^^ Came across this today...looks like John is not the only one offering this type of oiling solution for tracked high-revving K20's...or maybe he was the first and others followed? Pics and diagram are useful for the discussion.
One question I have is oiling of the timing chain...how does that work? Normally it gets splash-fed from below with the oil pump. I know there's a small bleed feed through the tensioner plunger, so maybe that is enough? Or drip-down from the valve cover area?
I'll ask him about the tensioner. I'll also post some up close pics of the oil pan and area around external oil pump. As you know, John tends not to publicize his work so much so who know how long ago. They were building K race motors pretty much the first year it was available in the US, or maybe even sooner.
Regarding the tensioner, he uses a stock one. He found the reason folks break tensioners is bad cam design. Get the cams right and you not only make more power but the tensioners stop breaking.
I'll ask him about the tensioner. I'll also post some up close pics of the oil pan and area around external oil pump. As you know, John tends not to publicize his work so much so who know how long ago. They were building K race motors pretty much the first year it was available in the US, or maybe even sooner.
^^ Found this also. If you click the arrow under the pic of the motor, there is a description of oil flow. It indicates that the tensioner is the source for the chain, though it doesn't say if it's the sole source.
I'm also curious if/why John isn't doing the cam tower oiling mod on your motor. He was one of the first to come up with that, alongside Joe McCarthy (RIP) and both of those versions are a little different from the TrackTuff one. Here's a thread with more on that: #5 Cam tower oiling mod - worth it? - K20A.org .:. The K Series Source . Honda / Acura K20a k24a Engine Forum OIf you search on that site, there are older threads from back in the day that have posts both from John and Joe. Maybe it's no longer needed once the overall oil pressure is under control?
Regarding the tensioner, he uses a stock one. He found the reason folks break tensioners is bad cam design. Get the cams right and you not only make more power but the tensioners stop breaking.
Oh so true!
Been down that road. Big cams with steep ramps need big springs to control them. And the tensioner doesn't see full hydraulic pressure from the oil pump until at least 3000 rpm, relying instead on the little spring inside to provide some force. During the overlap period of cam action, the exhaust side will run down that steep ramp as the valve spring overloads the chain tensioner spring. You can hear it just turning the motor over by hand. When running, you hear it on decel especially at lower rpms and/or more intake cam advance Rap, rap, rap! Eventually, stuff breaks...tensioner teeth and/or chain. I've done both. Now I use cams with more overlap & less lift to get area under the curve...and softer springs.
Speaking of cams, there is a new line out from Skunk2 (Ultra) and now Drag Cartel has responded with their version (Elite). Seems like they are doing something different with the ramps to get a bit more area under the curve.
I don't know about the cam tower mod. I can ask if it really matters though.
We missed Miatas at MRLS but we should be ready to go for 2016 with this beastie.
BTW, this car is basically for sale once it's done and dialed in . No idea what I'll ask for it. Comedy expenditure like any project car with piles of custom work. Most of that vaporizes with the FS ad. Like Moti selling his Locost, I have to pare down the number of projects I have going. Now with the ND and OGK project, Deviate would sit in the shop and not get driven much. That would be a crime.
View from the underside of the Hayward based IM. 64mm OEM TB with some blueprinting by Hytech. Everything is matched and smoothed out internally. The IM is actually pinned in place to guarantee perfect alignment with the port matching. Intake runs down then back up to frame rail then back towards clutch master in order to get correct intake pipe length.
I forget what alternator this is but it's not what was recommended in the kit. Space constraints and packaging dictated something from a different Honda. ATI damper. Bit of the custom oil pan seen here.
Bottom of the 7 qt oil pan. Button head fasteners in tray are for the internal baffles and trap doors to control oil movement in the pan. You'll note there is no pass through for the exhaust. We rerouted the exhaust to get a better header design and also increase oil capacity by about 2.5 qts.
This is the reinforced cut out in the PPF for the exhaust to cross over to the left side.
09-23-2015, 12:07 AM
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