L series Head swap?

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I have a question that i'm afraid no may have an answer for. I just bought a '07 Honda Fit a few months ago and found out maybe 6 weeks ago that the new '09 Honda Fit engines will have i-Vtec where my car only has Vtec, not to mention the kind seen on K20A3 engines that enage around 2300rpm.

So i'm wondering if anyone has any idea if you could swap the head from a '09 honda fit and put it on a '07 honda fit and if i'd have to change my ecu to that of an '09 honda fit for the VTC to kick in. I read a few post about people swapping k20a2 heads onto k20a3 engines and it seemed pretty easy.

In case anyone is interested the power difference between the two engines isn't very much, about 10hp difference, the big difference is where the hp peaks '07 engine peaks at 5800rpm and redlines at 6500rpm, '09 engine peaks at 6600rpm (i don't know where it redlines hopefully above 7000rpm).

So yea any help would be greatly appreciated.
 
Honestly, You'd be slower IMO. Peaking EARLIER is better for a car like that because it takes less time to get to that RPM and the tranny is geared for economy so its gonna take you a while to reach those revs anyways. same thing like with my 92 Civic CX, I have a minime swap, but my torque peak went from 2800rpm to north of 5000. Sure I have LOTS more hp, but my tq and hp used to peak faster causing for a quicker launch *I'm swapping out a SI tranny to fix this problem for me, I don't know if you have the same option*
 
Huh? That makes no sense. You need to compare the power and torque curves, not just peak numbers and where they occur.

Panther- there's no way to tell until the new engine comes out. If the head bolt patterns are similar, then you may have a possible swap.
 
Huh? That makes no sense. You need to compare the power and torque curves, not just peak numbers and where they occur.

Panther- there's no way to tell until the new engine comes out. If the head bolt patterns are similar, then you may have a possible swap.

I'm sorry, that doesn't really make sense after reading it either.....

Either way I can't imagine voiding a warrenty is worth like 10-15hp
 
Honestly, You'd be slower IMO. Peaking EARLIER is better for a car like that because it takes less time to get to that RPM and the tranny is geared for economy so its gonna take you a while to reach those revs anyways. same thing like with my 92 Civic CX, I have a minime swap, but my torque peak went from 2800rpm to north of 5000. Sure I have LOTS more hp, but my tq and hp used to peak faster causing for a quicker launch *I'm swapping out a SI tranny to fix this problem for me, I don't know if you have the same option*

Actually the transmission in the fit is pretty fast and quite a bit different compared to your CX transmission, it's even faster than the Si transmission you're thinking of swapping.

I know there's more to power gains than just peak horsepower and such, but the engines are the same only difference is one has i-vtec and another one doesn't, the power curves should me comparable, even the engine codes are the same L15A.

And sure there arent a lot of gains but it increases the amount of time i'm in my powerband and it also creates a better base for other mods to be added onto.
 
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I'm sorry, that doesn't really make sense after reading it either.....

Either way I can't imagine voiding a warrenty is worth like 10-15hp

Nope, voiding the warranty may not be worth it for most.

As far as the power curves, you really need to look at the shape of a dyno plot before you knock an engine that peaks up higher, especially if it makes more peak power. That engine may have more power at all rpms when compared to the old engine- so even if it peaks higher, it will still be more driveable and have a friendlier power curve.
 
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