Question about building a 400hp+ F23

[rexload]

Can 400 whp be done and pass emissions sure, i do it every year
Youll just have to do some swapping here and there around that time, ie injectors ecu yadda yadda, pretty sure you can handle it...


Now as I can tell you from experience stock pistons ringlands will start to go around 14+ psi on a t3 frame turbo.

Obviously you know you'll need the supporting mods to do so, preferably not a turbo you have to run megaboost to make goals, less boost=less cyl pressure=less heat= less strain yadda yadda.

when converting to obd1 immobilizer is not an issue, its in your key, and around ignition switch, no removal needed. However you will have to convert 3wire-2wire IACV

Will the F23 head make 400whp stock, I believe it can an will.

Hope this helps..

Yes, thanks, now looks like this should be a pretty straight forward build.
So from what I understand you are running the stock F23 cam?

not to thread jack,^^^ but wont the car run like absolute **** after you put your factory ECU and injectors and stuff in?

This is actual a very common concern,I need to pass emissions and didn't think it was possible to build a block and do it..LEGALLY..ha

and again,sorry if i hijacked.

You have to:
1. Put the stock ECU back in
2. Convert everything back to OBD2
3. Put the stock injectors back in
4. Remove the spring from the wastegate so you don't build any boost
5. Put the cats/stock o2 sensors back on, etc

Then you should be ready to rock and roll to pass the inspection (correct me if I am forgetting anything)

You will need to drive your car like that for a few hours to make sure enough sensors are saying READY when they do the OBD2 test. If you don't then they just tell you that you need to drive your car and bring it back because there is not enough information. So just drive it slowly on some back roads, around a lake or something, no need to get on it.


I also don't see any problem with running a fully built/sleeved block and still passing emissions. Unless you are drastically changing the displacement and/or compression of your engine, the ECU shouldn't be able to tell the difference

 

[1NonlyAccord]

I understand the process of what needs to be back stock..But when your talking about a fully built motor..You most likely will use low compression pistons,and everything else,so thats why im saying the car will run very very bad? am i right or wrong?

 

[BlkCurrantKord]

You can't run a fully built motor on the stock ECU and expect to get 400hp out of it. You could run an obd2 compatible ecu (aem fic) and still pass emissions, provided it's tuned properly.

Even if they cant get it to scan, they can always just put it on the rollers and use the sniffer test.

 

[rexload]

I understand the process of what needs to be back stock..But when your talking about a fully built motor..You most likely will use low compression pistons,and everything else,so thats why im saying the car will run very very bad? am i right or wrong?

The F23 already has low compression, there is absolutely no reason to lower it even more. I'm pretty sure even off-the-shelf pistons don't lower it a significant amount.

You can't run a fully built motor on the stock ECU and expect to get 400hp out of it. You could run an obd2 compatible ecu (aem fic) and still pass emissions, provided it's tuned properly.

Even if they cant get it to scan, they can always just put it on the rollers and use the sniffer test.

You have to be kidding me! Please show me where I said that I will be running the stock ECU.

They don't have rollers in every state. I live in PA, there is only the scanner test.

 

[1NonlyAccord]

Im already boosted..along with some others thats tryed to help. Everyones just trying to help.Even if some of them got off the topic..ha No need to argue with people.

 

[rexload]

I appreciate all the responses, seriously.

Just can't understand why somebody would tell me that I can't run a built turbo motor on the stock ECU when I already made it clear that I will be running OBD1 and have extensive experience tuning boosted engines. Sorry If i was being rude though.

 

[1NonlyAccord]

well My question was for the 10min emission test...I THOUGHT if you built your motor dropping the compression to what 8.5? like others are doing,and maybe some head work..When its time to swap back to factory injectors,ecu.ect ect the car would run like absolute crap and throw off idle RPM ect..That was my concern and question, Idk what the others where saying.ha

 

[bovodo]

correct me if i am wrong, but to switch to OBD1, you'll have to dis immobilize the car, when you switch back to OBD2, won't you have to re engage the immobilizer? quite complicated. i recommend just keeping the civic as your weekend car, and leaving the accord engine stock. 6thgen accords are on the average are high mileage and will not perform well as is. Just drive it as is. It'll be nice to get 30 MPG.

 

[nyknick1015]

well lets try to make things a little clearer...

im gonna start by saying that it hoestly depends on the location you live in that determines if you pass inspection. I can pass upstate no problem but with NYC emissions, if you have a car that is meant to be OBD2 but is not because you converted it, IT WONT PASS... its all about location thats first.

Secondly the process to switch back from obd1 to obd2 seems plausable, yes you can do it yearly on a regular but the only reason why i dont recommend it is because 1) hours of work just to put it right back on later, 2) by the time that you put it back WHAT IF you throw a CEL, 3) there is a 5050 chance that you are gonna mess up your tune. you put the chance that you put something back wrong and it starts fukign up

Third is because if where u live is like NYC, the machine wont read the ECU unless u drive at least 50-100 miles so the ecu can recollect all the data back.

and finally, if u build your block/head and try to disconnect everything, just to go back to stock, your car WILL WITH OUT A DOUBT run like ****

I personally think its gonna be quite annoying but if u can do it then so be it

 

[hotaccord243]

Man, So glad i don't have to deal with emissions (not to be an a** at all).

Can you upgrade valves/valve springs on the f23 head and still pass emissions? that will help the head for higher flow for sure.

Either way, yes the F23 head CAN flow to 400+whp, without a doubt. I am going to be going for a re-tune here shortly, and will surpass the 400whp mark in the next month or so. It is very possible, but to make sure that is done right, there is quite a lot of money and time that goes into it too.

Unlike a civic where everything is ready available and ALOT cheaper and you can spend only a couple thousand bucks and run some high power setup without a lot of work....