Here is another k20 swap.

homegrown32

True Classic
Well I thought I might start posting up some pics and information on my K20 swap.

K20a3 motor, K20a2 head, K20z1 cams.
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Nice. I hope to get more details in the future. Really interesting is your expansion tank + hot-side coolant system. Is your radiator "flipped" or switched? The photos make it appear as if you've switched the hot/cool sides.

I also really dig how you mounted the end of the trans to the drivers (left) side of the engine bay.

Nice work on the exhaust - that looks rad and should sound amazing.

One final question: what is this (your third photo)?
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The “expansion tank” I actually designed to work like a swirl pot in the cooling system. It is there to help separate air from the cooling system I will connect the swirl pot to an expansion tank to keep the system full of coolant. The radiator is a VW scirocco and the swirl pot will connect to the top side.
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3 of the 4 engine mounts are modified stock Acura RSX engine mounts.

The picture you asked about is the shifter box from an Acura RSX from Hybrid Racing. I modified it to fit in the tunnel. I think it looks cool and it feels like the shifting will be tight and crisp.
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Welcome! Very cool build! Looking forward to more details & pics of the setup.

Much interesting work going on there - I'll probably think of more questions reviewing your pics - a few quick ones -

Did you simply box the original suspension crossmember here - or rework it entirely? If so, what did you do to maintain suspension geometry?

Since you built your own engine subframe/cradle, how are you connecting to stock subframe points? Same as the MWB setup?
How did you determine engine/transaxle height for correct axle/CV travel & alignment? Trial & error or...?

Did you open up the ports on the shorty header? The one I have on hand shows a significant flow impediment in the flange design, even though the runners are slightly larger than stock.

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I like your reverse shift gate setup, seems cleaner than running cables under & back, how did you ascertain geometry of the gate transfer mechanism?

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Also interested to see your take on the t/stat side coolant line adaptions.

Are you going to use Hondata, K-Tuned or K-Tuner adapted EMS? Or something else?
 
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For the rear crossmember I made a new one out of rectangular tubing and mounted the stock suspension pickup brcket back on the new crossmember. To make sure it was in the same location as originally I measured and drawings of the original location with dimensions to points that I knew I was not going to cut away.

I think the engine cradle design is similar to the MWB setup. It mounts to the stock lower engine mounting points, and control bushings bolts. But for engine mount I am using urthane bushings mounted in double shear.

On the transmission the belcrank in the pictures is not correct! When I was trying to figure out the wiring I discovered reverse was where 1st belongs. I reversed the direction one to many times in my hesd. I have a new setup now I will post up some pictures later.
 
Very nice, homegrown! All stock a3 internals? What is your projected whp? Any changes in the lubrication set up? Hondata? The Hybrid Racing shifters are really nice.
 
Hasbro,
Yes all stock a3 internals from a base RSX. The way I understand it the oil pump is the same as the a2 (for the RSX a3) just no oil squirters. The only engine mods are; head, Intake and cam swap. The best I can estimate it should be just about 200 at the crank. I am running aluminum flywheel and crank pully. So it should rev quickly. I am running a k-pro from hondata. The a3 only has a slightly lower compression ratio. This will be good if it gets a turbo down the road.

And thanks for all the positive feedback.
 
The A3 also has a very nice similarly shaped torque curve to the K24, just at a lower rate. Good on the oil pump and will be good to 200 na with a safe 7600 redline. It's a shame you didn't keep the RSX intake.:D
 
I was kidding. The intake really impaired performance but gave the RSX about 5 lbs. more torque.
 
LookforJoe's, you asked about the headers and the Flow restriction at the header flange.IMG_20181217_221905.jpghere is an image of mine I hope it helps. I was not able to get a very good picture sorry about that. if you want more detailed pictures I can get them to you just let me know what you're looking for. I started with an eBay header. I think it cost about $49.I was looking at your build pictures of your header and exhaust just wondering if you were back purging with argon and helps the weld quite a bit both inside and out. But it really helps a lot on the inside it reduces the "sugaring".
 
Tons of really great work here.

I am going to pick on one thing, not because of the craft or the idea but because I am concerned about a potential fatigue failure in your future. Feel free to ignore this and no offense is intended to the choices or quality of your work.

You connection of the head flange coolant pipe to the piping of the surge tank and the amount of piping related to the the surge tank looks ripe for failure over time. I, like you, prefer to minimize the number of joints and possible leak points in a coolant system, however I think a judiciously chosen rubber hose section between the head and the tank and support bracketry for the tank would be worth considering. Engines vibrate a great deal and welding a casting to tubing with high dynamic loading rarely goes well over time.

As a secondary benefit, a molded hose with transitions can flow better than a hard turn in a pipe as well as isolate a the parts from vibration.

No offense or judgement intended, just hoping to fend off a future immediate loss of all coolant.
 
Kmead, Thanks I appreciate your comments. A healthy dose of skepticism improves the end product.
I thought it would be ok because I am mounting it on both sides of the head. There is a tab off the left side of the tank that is about 2" long and .100 thick, triangular in shape that I thought would support the tank.
Where do you think the failure point will be?
 
Nothing personal, this is my beef against the whole idea of the K20 swap, since every one that's posted pix of this area shows a huge chunk taken out of the box section of the lower left chassis to make room for the trans. Same for the huge chunks taken out of the chassis member at the lower front of the engine compartment.

I just hope that Giacosa and Puleo put enough over-engineering into the back half of the car to compensate!
 
LookforJoe's, you asked about the headers and the Flow restriction at the header flange.View attachment 17699here is an image of mine I hope it helps. I was not able to get a very good picture sorry about that. if you want more detailed pictures I can get them to you just let me know what you're looking for. I started with an eBay header. I think it cost about $49.I was looking at your build pictures of your header and exhaust just wondering if you were back purging with argon and helps the weld quite a bit both inside and out. But it really helps a lot on the inside it reduces the "sugaring".

That version appears to have better sized ports than the example I had, unless you gasket matched them? I was mostly curious if there were production variations with the cheap header. I didn't use the shorty flange because it was going to be more work enlarging the ports to size than with the factory manifold flange. I didn't back purge. Using Tony's method of no-filler & low amps on the runners, there is very little 'sugaring' (good term for it :) )
 
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