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So I picked up a 2008 Si for $2500 last weekend. PO craked the oil pan and now its knocking. So after thinking about it all day and not wanting to try to save this engine then have it come out more expensive than swapping it out i have decided to drop in a K24a2 from an 07 tsx. I can get one through my job for about 1200 with 6 month warranty and 88k. Ive been reading that ill have to swap over some parts. There are so many threads that im not sure who is right and what needs to be done. So heres what i take from it.

Flashpro

k20z3 Intake manifold

k20z3 50* vtc

All my k20 accessories

I read i can use the oil cooler from the k20? Any special modding needed to be done to the k24 or just bolt on?

Oil pan from K20z3

swap every single sensor from my K20z3 to the K24a2

Crv pass mount and bracket or is it just the mount bracket with the Si Motor mount? Also what year parts from the crv?

Is this all it or am i missing more?
 

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Yes the oil cooler can be transferred over. Just simply unscrew the oil cooler and the threading that's in the block and switch it over. There's a thread on it over at 8thcivic.com in the engine swap section. And you just about got everything correct. Not much to it!
 

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I am new, so I don't know if I should add to this old post or create a new post.

But, wow, this is similar to my situation.

I purchased a 2007 civic si with a destroyed engine. I already have a K24a2 from a 2008 tsx (86K)


I am located in California. So smog laws mean I need to run stuck software and due to funds I need to run as many stock parts as possible. Until I can upgrade as I continue to drive.

Should I swap over the 50° cam gear? Will the additional cam advance over the 25° tsx gear cause the valves to contact the pistons?
Remember I need to use the stock civic ecu (untuned) to get through smog
 

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Not every single sensor swaps over. Their are a couple that you need to keep from the k24a2. The frankenswap sticky a user posted uses a k20z3 head and k24A2 block and lists the sensors that do not swap over.

Also, probably the biggest problem you will run into is header fitment. The taller deck height even with the CR-V mount doesn't allow stock or race headers to clear without modification. Custom ASP is the only way to go.

And swapping the 50* Vtc over does not create piston to valve contact.
 

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Thanks for the info.
I will check the sensors and see what I need to use. Should be straight forward.

Thanks for the confirmation on the vtc.

I am surprised the stock exhaust manifold does not clear. It looks like there is more than enough room above the stock manifold and exhaust to move up 3/4"
 

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Swap is done! Busy day. I started at 8 this morning. Drove it home at 5, that includes a parts run for a pilot bushing and replacing the oil cooler o-ring I pinched, but didn't notice until it left 3 quarts on the ground ?

The stock exhaust manifold and exhaust do not contact anything. At least not that I can hear. There is over 3/4" of clearance all the way back until the catalyst. Then the heat shields are about 1/4" but a heat shield is easy to clearance ?

The parts that need to be used from each engine needed to be expanded a bit.

The alternator bracket from the K20z3 must be used if you want to use the oil cooler. It has specific coolant passages for the cooler.
Same story for the water pump and gasket.


The coolant pipe (from the thermostat, around to the back of the engine for the heater hose) from the K24 should be used. You might force the K20 to fit but the k24 fits properly.

Don't forget to have a spacer for the intake manifold support.

I used stock exhaust, the manifold support will fit with some careful reforming. I put it in a vice and hit it with my 3 lb mini sledge until it fit right.

I used the stock intake (for now) 2 bolts for the air filter box go to brackets mounted to the cylinder head. The 3rd mounts off the trans and will need a spacer and longer bolt

The crv mount uses different size bolt to the body side engine insulater. I stole 2 from the lower rear torque mount. Pn# 90168-S5A-000

All told it is really great to finally drive it.
I am using the stock civic ecu with stock software.
Balance shaft delete.
K24a2 (2008 TSX)
All stock Honda parts.

It has tons of power, easy to drive. I didn't even notice the extra vibrations. Felt nice and buttery smootj like Honda made it
 

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I hope people still look at this thread...

I just finished my K20/k24 swap in a 08 Civic Si and when I went to startup, it idled at about 2,000 for about 30 seconds before dropping to 1,000 rpm where it then stalled and turned off. I have Ktuner and logged the data but am not familiar with how to interpret the data. Does anyone know what might cause this kind of issue?

https://youtu.be/I4aWEcsh7kM

https://youtu.be/osSl7uHvzTY


Any advice helps!

Thank you
 

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...idled at about 2,000 for about 30 seconds before dropping to 1,000 rpm where it then stalled and turned off...
Yes, the idle tune is off optimum.

1) Which unit does MAP use? If this is in mbar, it is way to high for idle, even if you have huge stage 3 cams.
2) Lambda mapping is to rich, this need correction
3) Idle ignition timing is way to advanced, setting should be around 7°-11° BTDC
 

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Yes, the idle tune is off optimum.

1) Which unit does MAP use? If this is in mbar, it is way to high for idle, even if you have huge stage 3 cams.
2) Lambda mapping is to rich, this need correction
3) Idle ignition timing is way to advanced, setting should be around 7°-11° BTDC
Hi Lotus. Thank you for replying!

I think the units are mbar. It is the only one that would make sense I think. I can double check when I am home later. I noticed the high MAP reading too and checked for vacuum leaks and did not find any. I was going to test the MAP sensor to see if it was bad next.

could the lambda reading be caused by the throttle closing due to the low vacuum reading, thereby starving the engine of O2? again, pointing towards the MAP sensor.

How can I adjust the ignition timing?

Thank you again. I hope I can finally drive her today!
 

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Arouse the DAMPFHAMMER!
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...I think the units are mbar. It is the only one that would make sense I think.
Please check harness, connector, sealing of MAP sensor and the Sealing of all interphases...up to 600 mbar is way to high for an internal stock near Frankenstein.

...could the lambda reading be caused by the throttle closing due to the low vacuum reading, thereby starving the engine of O2? again, pointing towards the MAP sensor.
Injector duration is calculated by MAP, IAT and engine speed and the VE map, which is here an injector duration map equivalence. The last one is way too far off optimum, which is lambda 0.99-1.00.

...How can I adjust the ignition timing?
Easy for me. If you have no idea where you shouldn't do it yourself. Once you've done an adjustment and upload it and the engine don't like it, you will have a mess or risk and accident in the worst case.

Thank you again. I hope I can finally drive her today![/QUOTE]
 

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Please check harness, connector, sealing of MAP sensor and the Sealing of all interphases...up to 600 mbar is way to high for an internal stock near Frankenstein.

Injector duration is calculated by MAP, IAT and engine speed and the VE map, which is here an injector duration map equivalence. The last one is way too far off optimum, which is lambda 0.99-1.00.

Easy for me. If you have no idea where you shouldn't do it yourself. Once you've done an adjustment and upload it and the engine don't like it, you will have a mess or risk and accident in the worst case.
[/QUOTE]

ok so here's the update. Still no luck getting it going.

The main thing noticed was the vacuum reading by the MAP sensor (in mBar) is very high, or low vacuum. Therefore I checked and replaced everything below.

• checked engine harness and all connections of sensors and hoses
• Replaced injector o-rings
• Replaced intake manifold gasket
• Cleaned throttle body and replaced gasket
o My car does not have an IAC valve
• Replaced the PCV valve
• Replaced the canister purge valve
• Swapped the Map sensor with another that worked (both work and read the same)
• Verified the TPS works

Before install, the head was completely cleaned up and had a valve job done on it. Replaced all exhaust valves and intake valves were re-seated, and new valve seals…I don’t suspect they should be leaking. I will test compression tonight.

The only other things I can think of are

1. Timing is off
I double, triple and quadruple checked the timing chain when installed. I also turned the motor over several times (20 or more turns) with the pulley and it lined up each time at TDC.
2. Crankshaft position sensor is bad
3. Ignition timing is off
Would this cause a low vacuum reading by the MAP sensor?

DO you know anything else I can check?
 

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Are you getting codes that it's running lean? Which should/would be present if you have a big enough vacuum leak.
What do you mean the vacuum reading is high? My K24 FA5 usually shows -22KPa vacuum in FP - so that is normal.
What are you seeing for vacuum when it's running?
Is this tuned? It sounds like you're running a base map that just isn't up to snuff and you need to bring it to a tuner. Like Lotus said, don't mess with timing, ignition, or anything, especially if you don't know what you're doing. It looks like you're chasing issues that aren't really there due to it not being tuned.
The crankshaft sensor and ignition timing would not let it run for a small period of time and stall - it would/should cause issues immediately after starting.
 

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Swap is done! Busy day. I started at 8 this morning. Drove it home at 5, that includes a parts run for a pilot bushing and replacing the oil cooler o-ring I pinched, but didn't notice until it left 3 quarts on the ground ?

The stock exhaust manifold and exhaust do not contact anything. At least not that I can hear. There is over 3/4" of clearance all the way back until the catalyst. Then the heat shields are about 1/4" but a heat shield is easy to clearance ?

The parts that need to be used from each engine needed to be expanded a bit.

The alternator bracket from the K20z3 must be used if you want to use the oil cooler. It has specific coolant passages for the cooler.
Same story for the water pump and gasket.


The coolant pipe (from the thermostat, around to the back of the engine for the heater hose) from the K24 should be used. You might force the K20 to fit but the k24 fits properly.

Don't forget to have a spacer for the intake manifold support.

I used stock exhaust, the manifold support will fit with some careful reforming. I put it in a vice and hit it with my 3 lb mini sledge until it fit right.

I used the stock intake (for now) 2 bolts for the air filter box go to brackets mounted to the cylinder head. The 3rd mounts off the trans and will need a spacer and longer bolt

The crv mount uses different size bolt to the body side engine insulater. I stole 2 from the lower rear torque mount. Pn# 90168-S5A-000

All told it is really great to finally drive it.
I am using the stock civic ecu with stock software.
Balance shaft delete.
K24a2 (2008 TSX)
All stock Honda parts.

It has tons of power, easy to drive. I didn't even notice the extra vibrations. Felt nice and buttery smootj like Honda made it
What year for crv mount and did you switch over the 50 degree thingy?
 
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