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Old 07-12-2011, 01:21 AM   #21
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Well i have looked into k20 swap too. My friend drives a 2000 honda civic si with a k20z1, the car is right at 2500lbs and it made 221whp all stock on kpro tune when it was n/a. Even at 2500lbs he was able to beat bolt on srt-4s and mustangs, it was absolutley not disapointing at all, also it made 155ftlbs so thats still pretty damn good compared to what a miata makes. After about 6 months of N/A he bolted a precision 67mm non billet turbo on it and it made 430whp at 14psi on pump, all stock longblock. The civic si that came stock with the k20 came with a k20a3 or k20z3 which have considerably less power then the 20a2 and k20z1. If you plan on going turbo and rwd theres really only one way to go in my opinion, k24a4 its the accord motor, super cheap and they have made over 500whp on stock longblocks, add a2 cams and its an easy 25+whp gain, i do believe 600whp has been done on stock k24 shortblock. Check out k20a.org they have tons of info and theres even someone on there selling bellhousings for a toyota rwd 5 speed.
My only problem with the k-series swap is that it would prolly cost the same or more then a f20c and in my opinion it would be half the work to do a f20 then a k20 for approximately the same power, k24a2s are a little better then the f20c because they make tons of tq, theres a eg with a k24a2 stock motor on e85 putting down 568whp and 480 lb/ft. Stock f-series have made over 800whp and they do around 700 reliably with only headstuds.
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Old 07-12-2011, 02:53 AM   #22
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I think a k24/k20 hybrid would make a sick stripped out track rat. For the street...why bother.
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Old 07-12-2011, 07:32 AM   #23
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I've already decided my next swap is a K hybrid of some kind. Same difficulty as the FE3 swap only lighter, more power, better fuel economy, and more after market support.

I'm guessing 2 years, depending how long this motor lasts :P

Originally Posted by jacob300zx View Post
I think a k24/k20 hybrid would make a sick stripped out track rat. For the street...why bother.
THIS^^^ If you want to do this swap for a street car give your head a shake, only reason I'm going to is to be competitive in the class I want to run I have to be under 2000cc and make close to 300whp N/A
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Old 07-12-2011, 10:14 AM   #24
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Originally Posted by viperormiata View Post
That will never happen.
Xeleventy. I'm assuming the OP has never bothered to look at pricing for any of the Honda stuff.

For you guys considering this for a track car, a well-tuned K20A2 Honda weighing ~2200lbs (roughly 220whp, 160lb/ft) will definitely give a ~250whp turbo Miata a run for its money, if not walking away from it a bit. For somewhat comparative info, look up Honda Challenge H1 times. Those cars will weigh a little more in the 2500lb range, but will give you some idea of the potential. Not sure about tracks out west, but figure 2:10-11s on VIR Full. I've heard 2:09s, but haven't seen it personally. That kind of power comes out of a mostly stock motor, just header, intake and tuning.

Also, the K24 will naturally give you more torque, but at the expense of keeping revs down. They do NOT tolerate spinning too high.

Last edited by stinkycheezmonky; 07-12-2011 at 10:25 AM.
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Old 07-12-2011, 10:45 AM   #25
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My K20 civic friend and I left work last night and we decided to G-tech his car. I know a lot of people are skeptical about the G tech performance meter, and I don't swear by them, but I can tell you that on every car I ever used it on it was within 2 10ths of a second of a real drag slip time. My friends LS1 camaro G-tech'd at 12.9 on the way to the drag strip, he ran a 12.8 once we got there. My car G-tech'd at 14.4 about 2 years ago, and it ran a 14.3 that day at the strip.
Anyway, we took the 4 door Civic Si for a beat and made 4 runs. 1 of the runs the driver couldn't get it into 3rd which he claims happens all the time and it's a trans flaw with his car. 1 pass he spun big time on the launch and didn't get it into 2nd real fast...it read 16.4. The other 2 passes were consistent 15.8 and a 15.9. Eww. He was really pissed off since he just put I/H/E and Flash pro on the car, and he wasn't wanting to believe the G tech. We get back to my car, and I said, "let's line up, you yell 1,2,3 GO and we launch and see what happens, cause I know my car runs low 14's the way it sits." We did this, and I had the shittiest launch ever, but once I hit 2nd, it was like he wasn't even accelerating anymore. Due to my launch and my ***** footing, I bet I ran something like a 14.8 if that. 7psi in my car I'm guessing would be around 190whp and maybe 175 torque?? Maybe??
Based on cost, pain in the *** work, and major lack of torque...looks like I'm not doing a K swap.

Last edited by thirdgen; 07-12-2011 at 11:57 AM.
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Old 07-12-2011, 12:53 PM   #26
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Theres no doubt that you can make a new Si decently quick with some mods, and a civic swapped with a K can be really quick if you can keep it from breaking, but the exact same thing could be said for a Miata.

Comparing engines by street racing is very subjective and borderline meaningless.
For instance, I recall Tw34kd absolutely raped a Mugen Civic Si with the super badass K20A which makes 240hp bone stock. He did so in his old Civic HX with a stock D15B and an ebay turbo kit, probably not making much over 200hp.
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Old 07-12-2011, 01:17 PM   #27
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^Thats corrct because a new mugen civic si weights over 2800lbs where as the civic hx is the lightest honda you can buy aside from a crx hf it weights about 2100. 700lbs is a big difference, even if the eg made 180hp it would prolly win, and that 240hp is only about 210 to the wheels. And typical ebay turbo kit stock civic ex which is d16w/e raped me on 8psi and i was driving a bolt on 2002 mustang bullet that made 270whp. Weight is key. And those k motors are hard to break. But i still wouldn't put one in the miata, BP is an awesome motor and with the right hardwhere it can do amazing.
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Old 07-13-2011, 06:29 AM   #28
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Honda's are gay. Look how people post when they talk about them. It's so dumb.
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Old 07-13-2011, 09:52 AM   #29
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Unless you're doing it for class restrictions or whatever, what's the point of swapping in another 4 cylinder?
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Old 07-13-2011, 12:16 PM   #30
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Although I know stock k20's can make 650 whp+ on stock internals with c16 fuel.....Still would be easier to just get a LSx than have to do all the fab work of getting the k20 installed an running.
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