Anybody own a Honda K24W7 equipped Honda or Acura?

Was looking at a really nice TLX 2.4 with the K24W7. I really like the K24A2 but after reading about the W7, which Honda reversed the head flow & integrated the header with built-in cat into/onto the head. All in the name of efficiency & offsetting the block from the crank to have less drag on the pistons on the power stroke. So this all means no swapping an earlier K24 it it ever was necessary. This has been one of the benefits of Japanese cars to me, having a nice supply of low mileage replacement engines & transmissions.

Anyway having the cat built into the head to me is a really bad idea to me long term. Seems like Honda is going German & making things Uber efficient but to the sacrifice of long term dependability.

So the search for another family/wife car continues.

I could be wrong, but I believe it's more that the exhaust manifold is built into the head. The fact that they can do this with little to no power loss is pretty incredible, and the simpler exhaust makes for easier swapping.  

Simpler? No. Yes exhaust with cat is built into the head. What  happens at 75k miles when the cat clogs up? Can't just pop off the manifold & unclog it or install a nice high flow cat with a different manifold. Can't install a K20 Or K24A2 head because everything is offset & there will be interference. 

It's reverse flow from a K24A2 & others. A2 has the intake in front & exhaust in the back, W7 is reverse.  Plus it's direct injection. 
I was just wanting the K24 with the DCT. 

mdshaw said:

Simpler? No. Yes exhaust with cat is built into the head. What  happens at 75k miles when the cat clogs up?

That doesn't happen.  The cats aren't built into the head and they don't clog at 75k anyway.  Maybe 375k.  Maybe never.  I've never seen a restricted converter on a Honda, and only a couple that had failed efficiency, and those were on 200k mile V6s that burned a lot of oil.

If you have ever seen a J series V6, it's the same setup.

They do seem to eat starters at about 60-80k.  Fortunately they are much easier to change than the front-intake engines.

Can you share the source that says the cat is physically inside the head? That would be a new one for me.

I've seen newer K24 variants that have a single exhaust port (manifold of sorts cast into the head), but the cat is still bolted to the outside as part of the downpipe as is tradition. 

In reply to mdshaw :

I have seen some of your builds, and I'd say fro a fact that your Honda knowledge surpasses mine by several orders of magnitude, so I'm little help here.

All that said, my rudimentary google search confirms most of what you say-DI, intake and exhaust reversed from previous iterations of this engine, crank centerline moved, etc, but I found the K24W7 to have the "headifold", like the K engines have had for years. How is an in head cat possible? platinum cast inside an aluminum head casting? 

Regardless, I agree. I hated it when Honda went clockwise (though many engines since have been fine engines). Can anyone make DI work with anything but a factory ECU yet?

This is a K24W from a "G9" Accord, I assume that's 9th gen, which Wiki says is '13-'17.  Does adding the 7 to the engine model number make it an integrated cat?

In reply to newrider3 :

There's no converter in the head.  That wouldn't work with current engine management, there would be no way to install an upstream oxygen sensor (air fuel ratio sensor)

The cats are not in the head. They're further downstream in the exhaust pipe. It makes maintenance and replacement of the cats easier actually, becuase they're out in the open instead of being part of the exhaust manifold.

mdshaw said:

Simpler? No. Yes exhaust with cat is built into the head. What  happens at 75k miles when the cat clogs up? Can't just pop off the manifold & unclog it or install a nice high flow cat with a different manifold. Can't install a K20 Or K24A2 head because everything is offset & there will be interference. 

It's reverse flow from a K24A2 & others. A2 has the intake in front & exhaust in the back, W7 is reverse.  Plus it's direct injection. 
I was just wanting the K24 with the DCT. 

Dude the cat is not built into the head. It might bolt right up to the head; but, it is not integrated into the head. Most of the flanges on the integrated manifold heads are like a T3/T4 setup - just bolt a berkeleying turbo on it and send it. 

As you can see the exhaust manifold is integrated into the head and the cat bolts right up to that location. Companies make J/down pipes for those that act like a header. I've always been curious how Champcar or other crapcan series would rule the downpipe. Is it a header? No because the exhaust manifold is integrated into the head. 

Check out K24Z7s instead. They have the inegrated manifold design but still spin like older K24s. 

What? Why would they put the exhaust back on the front so it has to run under the oil pan to heat the oil even more? They FINALLY got it right with the K20/K24's and now they took a step back. Silly honda. 

Pete. (l33t FS) said:

mdshaw said:

Simpler? No. Yes exhaust with cat is built into the head. What  happens at 75k miles when the cat clogs up?

 

If you have ever seen a J series V6, it's the same setup.

 

 

Well, the 2003-up yes. The older J30/J32/J35 had traditional exhaust ports

bobzilla said:

What? Why would they put the exhaust back on the front so it has to run under the oil pan to heat the oil even more? They FINALLY got it right with the K20/K24's and now they took a step back. Silly honda. 

A lot of people are running the exhaust to the front now, and IIRC all Hondas are.  Personally, I think it's for clearance reasons, they can run a close coupled cat without having to have it sit far away from the engine to clear the axle shaft.  This means the firewall can be closer to the drivetrain, meaning more interior room.

Heating the oil, if it is even a consideration, would be a good thing when trying to get max efficiency in the 0-25hp range.

The L15-whatever DOHC is front exhaust, too.  So is the R18.

Pete. (l33t FS) said:

bobzilla said:

What? Why would they put the exhaust back on the front so it has to run under the oil pan to heat the oil even more? They FINALLY got it right with the K20/K24's and now they took a step back. Silly honda. 

A lot of people are running the exhaust to the front now.  Personally, I think it's for clearance reasons, they can run a close coupled cat without having to have it sit far away from the engine to clear the axle shaft.  This means the firewall can be closer to the drivetrain, meaning more interior room.

Probably less insulation required to keep the catalyst heat out of the cabin too.  And depending on the intake design, it might allow squeezing the engine back an inch or 2 for slightly better weight distribution. 

Thanks for the picture. I was reading a lot of K24 swap sites, don't remember  the one now that the way they wrote made it sound like the exhaust cat was not separable from the head.  I just have direct experience with K20A2 & K24A2. 

mdshaw said:

Thanks for the picture. I was reading a lot of K24 swap sites, don't remember  the one now that the way they wrote made it sound like the exhaust cat was not separable from the head.  I just have direct experience with K20A2 & K24A2. 

No problem. When they started switching to the "Earth Dreams" moniker or whatever it's called they went to the head with the flow direction in the opposite direction. 

Bear in mind, if you want the DCT, you are married to that engine.  You can't swap an older head on because they aren't direct injected.

Yes that's when the panic set in. For so many years Honda/Acura parts have been swappable, cheap, powerful & reliable.

I have a k24z3, I was initially worried about the same thing as you (want to swap a low mi jdm takeout if I kill mine and look for performance upgrades)

What I have noticed is the z3 is beginning to be supported by engine importers and aftermarket as they have been shunned by the A series fanatics thus driving price and buy in down.

This took a little time to happen and the w7 is still pretty new, my hope is the importers and aftermarket will embrace the new technology in the future.

Or what happened to me is a change of heart: I have grown to love the z3 for what it is and will likely never mod it.

mdshaw said:

Yes that's when the panic set in. For so many years Honda/Acura parts have been swappable, cheap, powerful & reliable.

They still are for the most part. It's just very generational now F/H/B/D, 1st gen K, second gen K, Earth Dreams, and now the L series is takin over everything.