K20Z4 build normal aspirated

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Hendri

New Member
Hi guys anyone build a strong k20z4 normal aspirated motor that can last(racing purpose).Need some suggestions.
Have calford cams in mind with titanium retainers double valve springs, a fully forged motor(still looking at rods and pistons) not exceeding 2150 cc, have upgraded the oil pump, water pump to electric water pump , hondata Kpro ecu already.Need More Power, need at least 3 seconds a lap on what I have now.
So far the motor is stock exept for the ecu, water pump and k pro intakemanifold.
 
Cams can shift the power curve to the right and end up rev'ing a motor beyond its comfort zone. Not a huge deal with drag racing but can be an issue with any endurance racing.

Did you mean a K20Z3? Oops....you're not in the states. Seems like (Wiki says) it's out of the FN2 which is the 07 Type R but hp rated seems pretty similar to a K20Z3 (201hp). Thought the Civic Type R was more hp than that. My K20A is (at the crank) 220hp from the factory (probably 195hp to the wheels). I'm around for 226-227 hp to the wheels now (header/intake/exhaust/kpro tune). Stock Type R motors are pretty reliable and I would run the stock bottom end until it got tired. A decent cam for them is Drag Cartel 2.2 Endurance camshafts. You'd need aftermarket valve springs and retainers too. Guys report issue lining up a big batch of Kelford cams (cam trigger seemed off when installing) but other guys had no issues. Proceed with caution.

I'd also think about bigger fuel injectors. Make sure your fuel pump is sufficent too. K-series react well to 3" exhaust. Megaphone downpipe on the header is a good idea too (I have one)

Details on suspension and brakes? Time shed can be found here.......in a mayor way.
 
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Hi Cafrog the motor is still stock.Fn2
Displacement is 1998 cc
Compression is 11:1
Limmit at 8500 rpm
Running a skunk2 pro c shock with megan racing sway bars, stifners, camber plates, got the car to handle better at 2 degree caster but need to get it to at least 4,5 degrees, dumping the megan camber plates and making up new ones in the week.
Bigger injectors are also in the pipeline 550cc with e50 255 intank pump and external fuel pump feeding from the surge pot.
Need to make up 1.5 seconds for 1st spot ,2nd and 3rd is were we are now with a 0.2 second diference to our rivals car he's running a fully built
b 20 motor not to worried about him need to catch no1 spent big bucks on his k20z4 with 179kw on the wheels.
 
What are the class rules? Will going larger in any area bump you in class?

There might be better things to do besides add power. Like lose weight, improve gearing, etc...
 
Hi Briansol have done weight reduction down to 936 kg, LS diff installed , gear ratio ok getting into 6th gear.
The maximum I can go is 2150 cc before we get bumped up a class, so it will be an 89mm bore with a 86 stroke witch should give me about 2140 cc.
Want to bump up the compression to about 14:1
 
Brakes been upgraded(4 pot calipers)had to modify the rims to fit the brakes, suspention been upgraded (skunk 2 pro c coilovers and megan racing stabaliser bars and camber plates and toe adjusters ), wing on the bootlet, only thing still standard on the car is the driver,the pistons, head,block and crank.
 
Many guys run without a front sway bar. But it depends on your spring rates and driving style.

Final Drive and each gear's ratio can be a big factor. But the track will often dictate what is needed. If you find yourself shifting up only to shift down soon after, probably a bad ratio for that track.

I would do camshafts and a quality stepped header made for your motor. I prefer ASP out of Washington USA. Kind of expensive though. You spoke of Kelford. They are a decent cam for the price. Just make sure things line up perfect when installing.
 
Spring rate is 11.5 front and 10 for the back seems to work well.Will look at the rates and do some calculations might go up on the rate a bit see if it makes a difference.
 
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