can a 2.4 iVTEC be remapped

If it has no outputs of its own and modifies most/all inputs to "fool" the installed ECU, I don't see how it could force the fuelling and ignition to be right with high-lift cams switched in and rev limit "adjusted" (another feature)
 
If it has no outputs of its own and modifies most/all inputs to "fool" the installed ECU, I don't see how it could force the fuelling and ignition to be right with high-lift cams switched in and rev limit "adjusted" (another feature)
Why not?, you can do anything you like as long as the person mapping it knows what he is doing
 
I guess so, in which case could I just add a Dastek and use that for the remapping without adding a supercharger, to start off with.

I appreciate that the supercharger will help give a lot more power, but my original question was "can a 2.4 iVTEC be remapped" and maybe the simple answer is "yes, with a piggyback ECU such as Dastek which can then be tuned to have several maps".

I am an electronics engineer, and putting in a piggyback ECU is easier than plumbing in a supercharger with intercooler.

If I add the supercharger/intercooler later, then obviously I will have to pay for another retune, but since I need the Dastek anyway, it might be a better idea (for me) to do that first and see what I can get from a tune of that.
 
Good plan, look on ebay, they do come up sometimes, I'm not sure weather you would need a Unichip B or a Unichip Q, so you'll have to do a bit of research
 
You're only in Shrewsbury, about 80 miles from me. Might send a PM in future an pop over.

It's been very helpful here :bigsmile: !!!!!!!!!!!!!!!!!!!!!!


b.t.w. there are some Dastek's on ebay now
 
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hey wrench pro . i have a honda accord 2.4 ivtec type s . 190bhp . i have had the same problem trying to find a tunning company to undertake it. i did find one in newry who specialise in driffting systems n tunning . i asked for a supercharger , which then needed bigger breaks . larger intercooler, fuel injection upgrade and remapped to get the best . cost 3200. expensive .now im looking for a new motor . stuck between 350z n 335d bmw .
 
hey wrench pro . i have a honda accord 2.4 ivtec type s . 190bhp . i have had the same problem trying to find a tunning company to undertake it. i did find one in newry who specialise in driffting systems n tunning . i asked for a supercharger , which then needed bigger breaks . larger intercooler, fuel injection upgrade and remapped to get the best . cost 3200. expensive .now im looking for a new motor . stuck between 350z n 335d bmw .

Hi Stephen, sounds same as my car. I found a tuning company local to me that said they could re-program the ECU for about £400.

However, I have also found out that there is a company in the USA called Hondata http://www.hondata.com/

They sell several different types of ECU for Honda engines, the best seems to be the K-Pro, but I contacted a UK company that sells their stuff and they told me that the K-Pro will not directly replace the ECU in the Honda Accord 2.4, and requires a lot of re-wiring to make it a kind of piggy-back. They said that any type of piggy-back onto the ECU for the Accord 2.4 is difficult and expensive. They said that the cheapest alternative is to buy a re-chipped ECU for about £400, which will only give an improvement of about 15 BHP.

I think (but am not totally certain) that the main difference between the 2.4 engine and the 2.0 engine is that the 2.4 is i-VTEC and the 2.0 is VTEC. The "i" is the problem !!

VTEC = Variable Valve Timing and Lift Electronic Control
i-VTEC = intelligent VTEC

In the VTEC, the lift and duration of the intake valves is controlled by using two different cam profiles.
In the i-VTEC the phase of the single intake camshaft is controlled, if you look at my pictures earier in the thread, you can see that there is one intake cam, the phase of which is continuously controlled by the ECU.

I think that the way the intake cam is controlled is the problem with this engine, because the phase of the cam is continuously controlled according to many sensor inputs. If you drive the car, it is extrememly smooth, it feels as smooth as a straight 6, with the advantage that below approx 4000 rpm it can give over 30 mpg.

So modifying this engine is difficult. If I had known this before I bought the car, if I was going to buy a Honda, I would have bought a standard 2.0 VTEC and modified that with the Hondata K-Pro !!!
 
I don't know a great deal about cars (yet), but I did a lot of reading around on this of late and have just signed up to see if anyone has been thinking along the same lines as me. The top topic in the Honda section is this! Clearly it was meant to be! :D

Anyway, I found this, which is a great explanation of how iVTEC works:

http://asia.vtec.net/article/k20a/

The technology is exactly as you describe. 30mpg at low revs, a smooth motor that feels like a straight 6, every people who know cars that I've given lifts to are very impressed that it's just a straight 4. The premise is maximum fuel economy and even performance across the rev and driving styles.

As a result, the engine has many stages of intake/exhaust settings on the valves which respond to driving style "intelligently". Therefore it's dependant on how it's driven. For over taking on motorways and A roads, down shifting to 2nd or 3rd, the engine kicks like a beast and sounds phenomenal with the textbook VTEC winy grunt. At moments like that, I truly love this motor. But this particular engine is sluggish to get going for sure (especially if like me you're in the tourer/estate :blink:).

But from my reading around, it seems you can modify air intake position and filters, whilst relatively inexpensive, doesn't really yield a great difference. Or I guess the mapping you discuss above. That does seem the more effective option, but still a tricky and relatively costly procedure.

I wonder if the sad truth is that we're driving a beastly 2.4 that you should be able to tune/map very highly, but can't. I mean it's currently set to about 180 or 190 bhp right? From a 2.4, you should be able to get a lot more power surely? But I think the nature of the iVTEC mean that it will never really reach it's full potential (power wise) without crazy money spent on it. It's an engine designed as much for economy, quiet and smoothness as it is grunt and power. So inevitably there's your compromise.

Anyway, I'll be following this thread if it continues, to see if anything can/is done to give it more grunt from stationary. That would be my main consideration if tweaking the response of the engine.

But to further comment on the whole iVTEC thing. I'm unsure how much I like the "i" aspect in retrospect. Maybe I'm being too simplistic, but in a perfect world I'd keep all the economical features for the low revs (I'm happy when I don't want/need acceleration) and simply set it so that the VTEC always kicks in around 3500rpm.

I rarely take it above 2000 most of the time. I mean, this car will almost drive itself on the anti-stall in 6th gear around town at 25 mph. I love that, I'll get 425 miles off a tank (super unleaded) when I drive like a granddad. But I'd like to always know when to expect the VTEC. With the "i" I'm never quite sure when it's going to kick in in ernest. I always get it when nicely when down shifting, but feel it's late to respond to upshifting, especially from stationary. Maybe I'm just not a sporty enough or clever enough driver to balance the throttle and gear changes well enough to get the most from the engine. It's just sometimes it goes like stink and sometimes it lags like anything, I'm not aware that I'm doing things differently. Do you know what I mean?
 
the problem with honda engines is the fact that they are low on torque,
i found both of mine unresponsive below 3000rpm and overtaking basically worrying unless you were over 4000




and as you have found out yourself from NASP cars it does take a few pennies to make a big difference
 
i found the same throttle response in my prelude with 2.2 vtec 1000rpm to about 3500rpm was slugish and left me feeling like i could almost run faster....lol....so i decided to see what i could do to make bottom end power . first thing more air flow (cold air intake) second manufactured a 1'' throtle plate allowing more air to sit in the intake itself so its not starving for air when opened up. third ported and polished the intake chambers to match the head and throttlebody for less restriction doing these 3 steps changed the responsiveness of the engine from slugish to wake up without breaking the bank little time and effort this my friend is my 2 cents yes you can spend hundreds on remaping but doing just a remap isn't going to solve the problem just create more
 
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That's interesting splashofpaint. I was actually looking at cold air intakes and was wondering what the likely impact would be. I understand they're pretty easy to fit and don't cost the earth to begin with.

I'm not sure, but I think the throttle plate on the i VTEC is a slightly funny design, meant to make the flow as smooth as possible. I don't think it's the typical butterfly type, although I could be wrong. But I think the throttle plate isn't necessarily a simple job on this engine.

What about exhaust? Did you do anything there? If so, what was the impact on the lower rev range?
 

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