So I've been searching trying to figure out if this swap is worth it. I have a K24a4 bottom end I picked up from work for free. Somehow it had spun a bearing and we replaced it under warranty. It's pretty bare (still has internals though), but I am wondering if fixing it, buying a head and throwing it in my hatch will be worth it.

I've been wanting to do a K swap for a bit now (looked at the k20a2 and the k24a2), but I cant help but think that this will still be a fun motor if I do it. I know it is different then the k24a2, and putting an a2 head on it isn't as simple as it may seem. So I would just mate it with an a4 head and drop it in. I just dont want to do all this and the motor kinda let me down after coughing up the fair amount of cash to do it haha.

So my question is, should I try just the k24a4? With say k-pro and tune. Or should I just go down a different road? Just looking for everyone's .02


Modified by _SHIFT at 12:36 PM 10/10/2008


Modified by _SHIFT at 1:10 PM 10/10/2008

 

Go with it, just use some K24A2 pistons and cams.

You'll want to replace the spun bearing, though.

 

bolting a a2 head onto a k24 block is more simple than a lsvtec/b20vtec...no need to tap oil lines n such, it just bolts rite up...i would find a a2 head and bolt that to ur k24a4 block..since ur k24a4 is bare i would go aftermarket piston n rodes bcuzz u cannot use stock a4 pistons n rods with a a2 head bcuz u will have piston to valve contact..

most ppl that do K swaps also change out the stock k24 oil pump for the k20a2 oil pump, since ur block is a a4 u need to modify the pump to make it fit the block, its not really hard to do..


if u were to do this K frank swap then u would rec. going kpro to prevent major damage to ur motor..

alot more info on k20a.org

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by toyomatt84 &raquo;</TD></TR><TR><TD CLASS="quote">Go with it, just use some K24A2 pistons and cams.

You'll want to replace the spun bearing, though.</TD></TR></TABLE>

Well yes, the spun bearing will be replaced haha. I'm just crossing my fingers that it didnt score the crank.

But the a2 cams will work in the a4 head? I guess I'm a little fuzzy on the difference between the k24a4 and K24a2. I thought the a4 was a dumbed down version without the exhaust side vtec? But if the cams will work, with those and the pistons and k-pro...it should be pretty peppy.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ekb16 &raquo;</TD></TR><TR><TD CLASS="quote">bolting a a2 head onto a k24 block is more simple than a lsvtec/b20vtec...no need to tap oil lines n such, it just bolts rite up...i would find a a2 head and bolt that to ur k24a4 block..since ur k24a4 is bare i would go aftermarket piston n rodes bcuzz u cannot use stock a4 pistons n rods with a a2 head bcuz u will have piston to valve contact..

most ppl that do K swaps also change out the stock k24 oil pump for the k20a2 oil pump, since ur block is a a4 u need to modify the pump to make it fit the block, its not really hard to do..


if u were to do this K frank swap then u would rec. going kpro to prevent major damage to ur motor..

alot more info on k20a.org</TD></TR></TABLE>

Hmm...I had just heard that an a2 head wouldn't work without some modification (oil pump, pistons and rods, etc like you mentioned). My block still has internals, just not some other things on the back of the block that were switched over.

The car is my DD, so Im lookin more reliability, but still fun. The a2 pistons rods and cams in the a4 doesn't sound too bad. But if a complete a2 head is 'better' then it's worth looking into as well.

 

if u had a k24a1 block wit the stock internals then a a2 head WILL bolt up without changing out the pistons n rods but since u have a k24a4 block then u WILL need to change out the pistons bcuzz of valve to piston contact...

if u can find a a2 head for cheap then u should get that and do a frank setup...im pretty sure a K frank setup will be alot funnier to drive then a stock k24a4 swap

 

What's the difference between the K20a2 head and the K24a2 head?

So like k24a2 head mated with my k24a4 block with a2 internals and k20a2 oil pump...Im good to go?

 

i dont think there is any major diff. between the k20a2 and the k24a2 head...i believe its the web design of the intake port thats diff...if u can get a k24a2 or k20a2 head then ur all set to go

 

The K24's head has VTEC only on the intake cam and not the exhaust cam from what I know. The K20 head would be a better choice because you'll get a higher torque output, according to my knowledge. As with any build, do your homework and research. There's a lot out there for a K24 Frankenstein build. Good luck!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Maverick2K4 &raquo;</TD></TR><TR><TD CLASS="quote"> The K24's head has VTEC only on the intake cam and not the exhaust cam from what I know. The K20 head would be a better choice because you'll get a higher torque output, according to my knowledge. As with any build, do your homework and research. There's a lot out there for a K24 Frankenstein build. Good luck!</TD></TR></TABLE>


u might wanna do alittle more research b4 u start posting info

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nikos;17820 &raquo;</TD></TR><TR><TD CLASS="quote">the tsx and type s head are pretty similar.. Only reason to put a type s head on a k24a2 from a tsx is if you have one ready to go and you don;t want to deal with making the tsx head work... The tsx head basically needs one port welded ($40) and a manifold that will work with it.

As far as the way VTEC works, both heads work the same way with the 3 lobe cams etc... So, if you don;t have a type s head laying around.. no need to buy one if you have a tsx head.</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _SHIFT &raquo;</TD></TR><TR><TD CLASS="quote">

So my question is, should I try just the k24a4? With say k-pro and tune. Or should I just go down a different road? Just looking for everyone's .02 </TD></TR></TABLE>

Yes, but add some Skunk2 Cams for the K20A3, either Stage 1 or 2. You should get horsepower figures very close to the K24A2 engine at a lot less money.

brian g

 

I believe that the k24a2 is a "true" vtec by having the 3 lobe cams on exhaust side as well.

If I'm getting this correct, to have my k24a4 with a "true" vtec, Ill need to change my pistons and rods from at least a K24a2, mate it with either a K20a2 or K24a2 head, and prob a K20a2 oil pump. With that set up, I should be looking at something closly equal to a factory K24a2, correct?

The other way to go is to buy a K24a4 head, get K24a2 pistons and rods and cams and call it a day that way. (This is my 2nd choice given that I still would have to change pistons and rods, but would benefit having a vtec head)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _SHIFT &raquo;</TD></TR><TR><TD CLASS="quote">I believe that the k24a2 is a "true" vtec by having the 3 lobe cams on exhaust side as well.
</TD></TR></TABLE>
Yes
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _SHIFT &raquo;</TD></TR><TR><TD CLASS="quote">If I'm getting this correct, to have my k24a4 with a "true" vtec, Ill need to change my pistons and rods from at least a K24a2, mate it with either a K20a2 or K24a2 head, and prob a K20a2 oil pump. With that set up, I should be looking at something closly equal to a factory K24a2, correct?</TD></TR></TABLE>
Actually you only need to change the pistons. K24A2 rods are stronger but only a little. The oil pump doesn't need to change, the K24A2 and K24A4 pumps both have balance shafts.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _SHIFT &raquo;</TD></TR><TR><TD CLASS="quote">
The other way to go is to buy a K24a4 head, get K24a2 pistons and rods and cams and call it a day that way. (This is my 2nd choice given that I still would have to change pistons and rods, but would benefit having a vtec head)</TD></TR></TABLE>

Yes, this is the way I'd go. You could probably find a head cheap. In fact I'd get a CRV or K20A3 head.

You can buy two K24A4's for the same price as rods pistons and bearings. The head K20A2 or K24A2 head alone will cost more than the Skunk Cams.

We've been running this combo for awhile and you can't beat it for cost.

brian g

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by brian g &raquo;</TD></TR><TR><TD CLASS="quote">
Yes

Actually you only need to change the pistons. K24A2 rods are stronger but only a little. The oil pump doesn't need to change, the K24A2 and K24A4 pumps both have balance shafts.

Yes, this is the way I'd go. You could probably find a head cheap. In fact I'd get a CRV or K20A3 head.

You can buy two K24A4's for the same price as rods pistons and bearings. The head K20A2 or K24A2 head alone will cost more than the Skunk Cams.

We've been running this combo for awhile and you can't beat it for cost.

brian g</TD></TR></TABLE>

Have any numbers by a chance?

I already have to replacing the bearing(s), and then get the pistons and rings, hone the block, then get the head and cams, and should be set right?


Some numbers would be awesome to see. I can see it being more cost effective, but it will still be pretty powerful and fun swap in comparison to any b swap I hope, and can be noticable.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _SHIFT &raquo;</TD></TR><TR><TD CLASS="quote">

Have any numbers by a chance?

I already have to replacing the bearing(s), and then get the pistons and rings, hone the block, then get the head and cams, and should be set right?


Some numbers would be awesome to see. I can see it being more cost effective, but it will still be pretty powerful and fun swap in comparison to any b swap I hope, and can be noticable. </TD></TR></TABLE>

if all u want is HP #s u should search around k20a.org and see if u can find other ppl wit the same setup and ask wut their HP #s are.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ekb16 &raquo;</TD></TR><TR><TD CLASS="quote">

if all u want is HP #s u should search around k20a.org and see if u can find other ppl wit the same setup and ask wut their HP #s are.</TD></TR></TABLE>


No, HP numbers are not what I'm looking for at all. He mentioned it being a good combo for the cost, and Im curious to know the facts and number on what something like this will yeild. I haven't seen anyone to do it quite like that myself, so that's why I was asking so I could compair and understand better.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _SHIFT &raquo;</TD></TR><TR><TD CLASS="quote">


No, HP numbers are not what I'm looking for at all. He mentioned it being a good combo for the cost, and Im curious to know the facts and number on what something like this will yeild. I haven't seen anyone to do it quite like that myself, so that's why I was asking so I could compair and understand better. </TD></TR></TABLE>

mybad thought u meant HP wise..cost wise ur gonna be looking at 5-8k if ur gonna do everything urself and buying all the parts u need...more and more k series parts are just starting to come out so they are quite expensive so it adds up quick..

rite now im at 5gs and i just have my longblock finished and still no drivetrain parts or anything else to drop the motor in

good luck

 

Go with a K24A2 Bottem End with a K20A2 Head.

 

I dont understand the point of a tsx bottom end with a rsx type s head. It has already been pointed out that these heads are very similar. I'm fairly certain that later model k24a2 heads came with more aggressive cams than k20a2 heads did. If it were me, and I wanted to leave the engine fairly stock I would stick to a tsx engine, or a k20a of sorts. So much more simple.

Not that the A4 is a bad engine. Friend's 04 accord is running top notch with 450,000+ km. Just not really a "performance" engine.

 

Hey I'm doing a similar swap, I have a K24A4 bottom end from an 2003 Accord EXL and a K20A2 head from a 2004 Acura Type S, now you guys said that the pistons need to be changed so there's no head contact, what would you recommend? and how would I know which rods and pistons to get? I plan on boosting this motor in the future, so I need low compression pistons.. My budget for pistons and rods is around $1000.. your help is greatly appreciate it.