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I put down my deposit last week. Bought a used head off ebay with cams. It's extremely obvious that Honda really dropped the ball on this head design. No V-Tec on the exhaust, plus that cast-in exhaust has to be seriously detrimental to the scavenging effect on the cylinders. I imagine the port work will help free up the exhaust flow and improve performance a fair amount. Obviously a tune will be required, but I think those guys out there with higher flow intake manifolds will be the ones who net the most, at least on the N/A side of things.

I'll try to remember to keep everyone updated as I go through this project.

20190918_101938.jpg
 

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I put down my deposit last week. Bought a used head off ebay with cams. It's extremely obvious that Honda really dropped the ball on this head design. No V-Tec on the exhaust, plus that cast-in exhaust has to be seriously detrimental to the scavenging effect on the cylinders. I imagine the port work will help free up the exhaust flow and improve performance a fair amount. Obviously a tune will be required, but I think those guys out there with higher flow intake manifolds will be the ones who net the most, at least on the N/A side of things.

I'll try to remember to keep everyone updated as I go through this project.

View attachment 478199
Keep us posted. Interested to see what kind of numbers this makes.
 

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I will provide more information as it becomes available.

I aim to have the camshafts measured, the stock head flowed and supply factory valve spring information (installed height, seat pressure, open pressure and coil bind height). It likely will be closer to the end of the year before the heads have been ported etc.

How much interest is there in performance camshafts for this engine? Has anyone taken time to set up a poll? Billet cams will likely come with a $1,000 to $1,200 price tag. I'd be willing to bet that with a head port, down pipe, cold air intake, cams and a tune, that some folks would be happy to jump on this path instead of going with a supercharger or turbocharger.

This is how I see it - everyone who goes with a forced induction setup will start off with a cold air intake, down pipe and a tune. You're already in for ~$350 for the cold air intake, ~$350 for the down pipe, $700 for the flash pro plus tuning... That's $1,400 assuming you know how to tune it yourself.

If you go with a turbo kit, you start at $3,400 (PRL non-intercooled). Realistically you're going to want an intercooler and the whole kit, so $4,300 for a turbo kit. + other parts and you're at $5,700 + tuning.

Supercharger kits start at $3,500. Add that to your other bolt-ons and you're at $4,900 + tuning etc.

Assuming you had the bolt-on parts and were previously tuned, you're going to start from scratch on the tuning, so double your tuning budget from your N/A build. Let's be generous and say you're all-in for $5,700 + Tuning (2x) for the turbo kit and $4,900 + tuning (2X) for the supercharger kit.

Let's say you want to spend a bit less money, make some solid N/A power that will also translate into an even better performing car after you add boost. Head port $1,100, cams $1,200 + bolt-on's $1,400 (includes flash pro) + tuning (once plus re-work for cams/head) - $3,700 all-in. Keep in mind also that all of the modifications on this route, will mean even better results if you decide to go with a supercharger or a turbo down the road.

I think there is a case to be made for the N/A route depending on the numbers from the head port and the cams. This route is for the guy who wants to do the head swap in a weekend without all the fuss of the K20 head swap, add some more fuel to their existing bolt-on's only tune, drive to the dyno for a re-flash on the new head port/cams.

Maybe I'm just weird, but I like to explore the path less traveled occasionally while learning something along the way.

What does everyone else think?
 

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Kevlar,

A few companies have tried making cams for the k24z7. All of them failed to make any power.

I don't understand why because I'm not an an engineer or understand motors that well, but many companies have tried to make cams. If you think you can do, by all means do it! I'd buy some if they made more power for my motor N/A. I love N/A Hondas. I'm eventually planning on getting the k20 head swap to stay N/A and reach 260+ whp.
 

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I'm interested in seeing how much power the head work makes. Years ago I had Isky regrind cams for me, as they didn't make cams for my particular engine. The regrind really helped. I didn't have any specs to give them, but they knew enough info to know what lift, duration, overlap to use, and gave me 2 options on this matter.
I believe this is why stock heads get turbo/supercharged...and N/A builds get K20 head swaps. If your going to try a stock head N/A build, I'm rooting for you.
 

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In my experience, it takes at least twice the money to make the same power naturally aspirated as you would if you went with forced induction.
Take it as you will. I'm not wanting to discourage you, I just don't want you to be surprised.
 

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Hey Guys,

I'm working with an engineer here at work to try to get this stuff figured out.

As he put it, "you've got the trifecta - dual overhead cams, solid tappet and VVT." Meaning that since the valvetrain is solid, there's no wiggle room on valve adjustment like there is for a hydraulic setup. Usually that's not a big deal, however with a dual overhead cam configuration, as soon as you cut into the factory cams, you cut into the base circle which in turn completely changes the entire valvetrain's geometry. This means that you're going to have to not only degree the cams in, but you're also going to have to adjust lash to suit. Again, this isn't usually a problem, but you're dealing with cams that are keyed/located off the cam gears in a specific way which also impacts how the camshaft position sensor registers all this. Again all cams do this, but since there is so little known about this engine and the limits on PTV etc it's a problem for us. In other words, if you regrind the stock cores and you want to daily this, you're going to want more than just a weekend to get it all squared away.

You have to ensure that 50 degrees TDC in Hondata is in fact 50 degrees TDC at the engine itself etc etc etc. Again, standard stuff, but most of us daily these cars and since the knowledge base on the engine is so low, we can't just go off of common knowledge like you can with the LS or Coyote etc. You look at LS1 Tech, and most guys can tell you with certainty exactly what compression you'll get with a specific head casting (243 for example) with an LM7 bottom end will net you like 10.0:1 compression. That's not the type of environment we have here. I think we will get there, as these cars get older and more people keep them as secondary cars for hot-rodding etc, but as we stand now there is far less of a technical foundation than I think we could expect to see in the future. Personally.... I don't think we're that far off, it just takes some folks to take the plunge on a backup engine and tinker around a bit.

The best bet here is to get billet or austempered ductile iron cores with un-ground lobes and then grind it so that you wind up with a factory base circle. Of course all of this is contingent on the amount of piston to valve clearance. While we do have timing chains and we generally don't have to worry about a timing belt breaking, we can't just throw more duration and lift at these camshafts without checking for PTV. Just off the top of my head, without doing any research, if we have issues with exhaust flow, increasing the exhaust duration a bit could be a good way to go - don't hold me to this. It's worth noting of course that increased exhaust duration can increase valve overlap which can decrease vacuum production and other ill effects - the saving grace being that we can change the position of the intake cam through the cam position table, AND that we can choose the V-Tec engagement point. Obviously with a head port, we may find that an increased exhaust duration relative to the intake may not even be necessary. Anyway, just throwing it out there. This is all rather uncharted territory for me. I come from classic Pontiac V8's and a daily driven bolt-on/tuned turbo volvo 6 speed.

If anyone has a spare K24Z7 bottom end, that may be the best way to go to ensure no power is left on the table by going too conservative on the grind AND that we don't go too radical, resulting in a PTV collision.

With that being said, it's alarming to me how many folks don't upgrade the valve springs when the put boost to these engines. Don't get me wrong, loads of people do it all the time with various engine platforms, but we've seen a lot of people pick up power on a turbo 5.3 with just swapping the springs to springs with more seat/open pressure and overall better harmonics. No tuning, no extra boost, just a better spring to control the valve.

I hope to have the stock cams measured, and once I do, I'll post it here for everyone to read. I'll also check out the springs for their seat/open pressure (on vtec, primary and secondary for open) as well as the rate and the coil bind. The fact we don't know this stuff bothers me lol.

If the admins will allow it, I'm happy to post a poll asking for input on camshaft interest. Even if you're boosted (supercharged or turbocharged), there is going to be power to be made with camshafts, period. Say what you will about the stock head etc, anytime you create a valvetrain environment that is more suited to the engine's needs, you're going to increase driveability and make more power.

9thGenisfamily - what cams did they regrind for you?


At the end of the day, we may put up a poll and have 100 people say they're interested, I'd bet 30 pull the trigger on them. Those 30 people need to make enough power to make the purchase justifiable and influence others. We'll see...

Thanks for hearing me out guys, I'll try to have something by the end of the week. SEMA prep is ramping up, so engineering is busy. May or may not have anything, no promises lol.
 

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In my experience, it takes at least twice the money to make the same power naturally aspirated as you would if you went with forced induction.
Take it as you will. I'm not wanting to discourage you, I just don't want you to be surprised.
Hey Homegrown,

Thanks for the input. Yeah, I don't doubt that at all! I just recognized that the approach that 4P is taking is in-line with how I've approached engine upgrades in the past. Obviously this market is geared toward bolting on superchargers and turbochargers, which is awesome! However this route allows me to play around over a longer period of time, learn something and be a pioneer of sorts. Plus it lets me work with some of the guys at work on something we typically don't tinker with.

I appreciate your thoughts!
 

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There are still 2 basic rules for making power on a naturally-aspirated engine - displacement and RPM.
If you can get more air into the motor, along with more fuel, you'll make more power.
Pretty simple. All engines are just air pumps - doesn't really matter if it's a pushrod LS motor or a K24.
Obviously, we're limited on displacement, so that leaves RPM. But with higher RPM comes the need for better lubrication and cooling.
At a certain point, you can't rev any higher without killing your engine.
And there's the crux of porting the cylinder head and changing cam profiles. Yes, VTC and other technologies can help, but by and large, you're moving the power band higher in the rev range. Not that big of a deal for a race car or an engine that gets refreshed on a regular basis, but no so good for a street car.
Yes, forced induction does come worth its own set of challenges, but some modifications carry more weight than others.
 

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Homegrown,

Once we flow the factory head, we'll have a better idea. Once flowed at various lifts, we'll have an idea of what this engine could really use without pushing the RPM range beyond the limitations of street applications. I would wager that a street port that cleans up the chambers along with a good opening of the exhaust ports would net lots of area under the curve without sacrificing too much bottom end. A good tune ought to mitigate any bottom end loss. Plus we have the benefit of not having to worry about torque converters etc. Our gear ratios are pretty solid, and quite honestly the lack of traction at low speeds with the factory cams/flow suggests to me that a sacrifice in torque from 700 to 1,500 RPM wouldn't be the worst thing in the world.

You are right that we are limited on displacement, and obviously PD blowers and centrifugal superchargers completely overcome that obstacle. A centrifugal blower however in theory is parasitic until it's "spooled up", much like a turbocharger. Sure the centrifugal blower is still working within the confines of the factory valvetrain and bottom end, but I would wager that in effect by opening up the runners, cleaning up the valves and adding cams, we're likely not shifting it so significantly that it would behave so differently, in terms of power band, than a centrifugal supercharger.

This is all hypothetical of course until we know a) the stock cam specs, b) the stock head flow numbers and c) the head flow numbers from the 4P port. The real trick, in my opinion, is avoiding a complete reduction in port velocity.. But yet again, we may have a surplus in velocity that could be sacrificed to net us the flow we need for gains under the curve. At this point, it's all speculation.

Again, we'll just have to see! I'll tinker with my desktop dyno program once I have factory flow numbers and camshaft data. While I would never lean exclusively on that program to pick camshafts, it's pretty good at illustrating patterns.
 

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Im really liking the idea of all motor, as this gen civic is the last of the vtecs. Even with dp, intake and tune, the car is great for me. With a built freeflowing head and possibly cams, i think these 2.4s would be a solid street and 1/4 mile contender.
 

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Some pictures after disassembly. The "reluctors/timing tabs" are held on with torx bolts. We're going to have to put these in a "vise" to break them loose. Progress is slow; we've been busy, so personal projects take a back seat.

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Andy Mac - I completely agree. With added exhaust duration, a port/cleanup of the exhaust and a good down pipe, we can compensate for the lack of vtec better than I think a lot of people think we can.

Having come from a factory turbo car as my daily driver, I love the naturally aspirated K-Series. Turbo technology grows leaps and bounds year after year, and although I have not driven the new 1.5T Si's, I like the idea that I've got the last last N/A K-Series. Plus, for $3,000 -$3,500 more, you've got a HELL of a forced induction kit whose technology dwarfs the factory turbos. There's a reason why Precision, Garret etc are selling their turbos for $1,000+, and it ain't just because they can, it's because their R and D is dedicated to our goals, not just cranking out OE turbos that are just ok. Don't get me wrong, they (Garret) make OE stuff too, but when you're building to a price point, there are always drawbacks. I'll take the added displacement and the proven N/A platform over a nearly 1.0 liter drop just for a factory turbo. Not to mention that 1.5 liters isn't going to be able to spool up a decent sized aftermarket turbo like our 2.4's can. I'm no turbo expert though, so I'm kinda just running my mouth at this point! LOL

I'll keep everyone updated as we move forward.
 

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Nice! I'm anxious to see how things turn out. I'm planning on rebuilding my short block here in the near future as I just supercharged my 9th gen. Adding this to my build will be great if it can provide decent gains.
 

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Hey Guys,

Sorry for not posting recently. My engineer friend at work thought that the K20 (VTEC Intake AND Exhaust) stuff we've done in the past would more or less provide us the right "file" for our ADCOLE machine to measure the camshafts I have, but that's not the case. He's having to write a new file for the ADCOLE machine to properly measure these cams. He's already busy with stuff that customers pay us to do, so he's doing this when he has free time.

I'll post the factory specs when they're available. Like I said, I put my deposit down for the 4 Piston program, so any updates on that front will have to come from them.

Thanks!
 

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wonder if just making a custom exhaust cam will net any power, especially for FI guys
 

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Hey Guys,

I've got the camshaft specs back from engineering. For now, we just have the specs of the camshafts at the camshafts, so we don't know the effective duration/lift at the valve etc until we get the geometry of the head nailed down. We've done K20's in the past for some road racing and drag racing guys, but the prints/geometries don't match up at all to the K24Z7. Journal diameter etc is close, but outside of that, we can't use existing CNC "directions" for these cams.

I'll post more once I know more about the head geometry. When I sought out more information on the cams in the TSX etc, no one properly articulates the valvetrain measurements so that we can get a true apples to apples comparison. Obviously that's a different engine etc, but just for the same of Advertised, Duration at .050" (at the cams vs at the valves) etc vs the displacement of the engine, that would give me an idea of how detrimental the lack of exhaust duration on the K24Z7 really is. Of course having factory flow data for the K24Z7 would also be super cool, but I don't have an ETA on that.



Quick question for everyone - what type of camshaft "line-up" would you all like to see? Obviously the TVS/Eaton/Rotrex guys could use more exhaust duration etc etc, but for the N/A guys, would you all want a "no springs required" grind option in addition to a "valve springs required" option? I've noticed that some of the other manufacturers recommend limiting your VCT cam targets depending on the camshaft selection, but I'd like to get a general idea of where that money spent vs gains sweet spot is for the majority of the guys out there. I think that a different grind for the 4 Piston Racing Port and Polish program would be beneficial, as I imagine they will pick up lots of flow in the higher valve lift range vs stock. I would think that a grind for that work would necessitate springs, but at this point I'm just guessing.

Thanks!
 
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