Non-VTEC engine idle around 2000-4000 rpm, depending on cams and aimed idle quality. So if you like the sound at idle more then any torque below 5000 rpm. Go with it.

Thanks for the info Lotus. I knew the torque curve got shifted up quite a bit, but I didn't know it went that high. That's going to be a bit much for what I'm doing with it, so I think I'll stick with a normal system.

Speaking of which, is it just the rockers and camshafts that determine the type of vtec system these engines use (two lobe vs. three lobe)? If it is, would a set of type s cams swap into the cr-v head with it's stock (cr-v) rockers, or would I need the type s rockers/ rocker shafts too?

 

Just to chime in, I have a set of 2002 type s cams for sale and I might have some a1 and a3 exhaust rockers to if you wanted to still go the vtec killer route. Pm if interested.

 

Also, I've seen that v-killer can be bad for idle and street use for some, but how bad. Annoying? Tunable with kpro? Totally unusable? I'm not looking for racing performance, but 200 whp is going to be my first goal. Any insight would help as this is my first time working with a Honda engine, so no roasts please 😆

A lot of good information is already here. Just want to add following regarding idle and tuning. I non-VTEC system makes only sense where valve train forces increases the wear too much or just can handle the engine speed no longer. Therefore lighter parts are used for the roller rockers. To get 200 whp out of a K24A1 you can use definitely a full iVTEC system. I recommend it definitely for your goal.

To the can question. Non-VTEC engine idle around 2000-4000 rpm, depending on cams and aimed idle quality. So if you like the sound at idle more then any torque below 5000 rpm. Go with it. But keep in mind the engine speed of the K24A1 at max. isn't given by the Valvetrain, it is given by the crank assemply and oil pump. Would be a funny car bouncing from 5000 rpm to 7800 rpm up and down. Below torque is missing, above safety is missing.

My wild guess would be an iVTEC system with a nice stage 2 aftermarket 3-lobe cam (not sure if the mod for that on the had can be done, but I think yes with some effort), stock head port, upgraded oil pump (maybe) and you will see 200 whp with an RBC IM, adapted injectors, a header and exhaust plus tuning (TB 70 mm)...did I miss something?

 

Yeah, I'll definitely be getting kpro. The engine's going into a standalone build, so there's no existing hardware to worry about. And I'm planning to stay NA for the time being, so I'm looking for the best flow possible. Do you have any recommendations for valve springs? I'm a bit weary of leaving them stock with locked rockers, especially with a higher lift cam.

 

I believe you can use the valve springs and seats from the type s or tsx cylinder head but I’m not sure. Maybe @Them Witches can chime in with a definitive answer.

 

Awesome, thanks for the info. So for the cylinder head swap, you mean to swap in the whole head and not just the cam/rocker assembly right? I was leaning towards the cr-v head because I've heard it has better flow, but I suppose if there's good gains to be had then I'd go for it. Isn't the z3 head the one with an integrated exhaust manifold?

 

I was referring to the 06-11 civic si head the k20z3. The crv head does flow very well a few cfm off the PRB type s , and for vtec killer applications is a smart choice. If you plan on getting kpro or ktuner it can be tuned to idle fine and drive fine on the lower end of the rpm range , but on a stock ecu it won’t be happy.

 

You are lucky to have a crv block it can take the 3 lobe head swap without any modifications. My best advice is to wait until a z3 or rbb cylinder head pops up and snag that to put on your block. I understand we are all on a budget , but locking the vtec on the stock crv cams will only serve to make it run like doo in the lower rpm and take away the fuel economy , although it will sound a bit cooler. Lol.

 

If you lock the vtec it will need tuned to run right down low. People let go of 02-04 type s cams Or z3 for a hundred bucks or less most of the time, there wouldn’t be any peak Power gains from locking your existing cams on the vtec lobe. The gains come from the higher lift cam lobe From the rsx/tsx/si cams the motor would be locked onto. Type s and 04-05 k24 cams are going to be the cheapest. Either with an extra set of crv exhaust rockers will get you another 30whp if you tune it.