Hey all, first off want to say thanks for those that could take the time to read this. I'll try to be quick and brief.
Subaru guy, new to Hondas - but incredibly interested. I currently own an incredibly mint 92 Prelude Si (H23a w/ auto...). I'm looking to swap auto to manual and do a solid H22a build. Now due to the transmission swap and because I'd like tunability, the P28 ECU is the logical option. However, I have some questions that I just cannot find answers to:

1. When the P28 is referred to as "chipped", what does this mean vs. non-chipped?
2. Will I need specific harnessing or can I use my H23a harness? If I need to change, what harness(es) specifically?
3. What software do I use to modify MAPs?

How about we start there?

 

Chipped ecu has the chip where you can upload or burn the fuel map setup (you need other hardware for that) so its not complete engine management system that you could tune it by yourself (thats hondata)

You just need to wire vtec to your current harness since your car didn't come with it

With hondata you can adjust about everything but its a lot more expensive than just chipped ecu

 

Is there a website that you can direct me to to look at this hardware? So a P28 ECU doesn't provide tuning flexibility? If not, then what's the benefit?

 

Chipped ecu is cheap solution that people can go to some dynoplace and they do the adjustments/tuning there (if they have equipment for that)

Ha motorsport and xenocron have ecu stuff

 

Oh wow, so there is no open-source software that is going to allow you to modify MAPs. Geez, well that's bogus. So if you get a bad MAP, you need to head back to the dyno and re-tune?

 

Why someone would want tune map? You dont have to touch working oem sensor

Or do you mean fuel maps?

 

Yes, I think we're talking different languages here. Coming from the Subaru world we had the Cobb Accessport, which would allow you to customize how you wanted your car to perform. Out of the many times I've had a custom MAP to perform for my car, I always had to adjust AFRs in some manner to get better results (whatever I was trying to achieve). Having a P28 ECU performing in one manner without the flexibility to adjust it on the fly concerns me.

 

Dont know is that turbo thing more but that kind of tuning is very inaccurate solution - you need to get more inside the fuel maps what those kind of solutions offer. Its kinda cheaping out and doing half *** job

What are you going to do with h22? Whats your goals?

 

That's a good question. I want to swap out the H23a/auto and do a pretty serious build. I first like to get a strategy and understand what I am getting into before I make a final decision. I have a lot to learn yet about Hondas so I'm not quite sure that I can say now. But I would definitely like to be in the 450 whp range. I don't think I can do that and keep it NA, so forced induction will be a part of the build - which is why I know I am going to need a tuning solution. Having used open source tuning software for the Subaru, I could monitor all of my ECU's processes and diagnose issues in real time - I would like that same freedom with the Honda. I know OBD1 is a bit crude in comparison to the OBD2 ECUs, but would still like to see what the ECU is doing through software.

 

Yes thats turbo setup and its not going to be cheap. Definitely you need hondata for that. And maybe sleeved block.

Imo youre just wasting money building fwd turbo setup. To make it any useful you have to new almost everything brake, suspension, engine and traction wise

 

Yes, I've been looking into a lot of this. The big problem is not money for me, but getting parts. I cannot even find an easy bolt-up 4/2-pot brake solution. Suspension components are limited. I love this car but the performance options are hard to find if even available. Civics have unlimited options, this car doesn't seem to have many at all.

 

K sport and d2 had brake kits atleast some years back.

Tanabe has sway bars and Innovative Traction Bar

Bc racing has suspension (also those brands which have brake kits). Lsd's can be found if youre not using oem lsd transmission. Aftermarket cams can be found... Piston selection widens when you sleeve the block

Mishimoto has radiators

 

I have a Mishimoto radiator already and a traction bar ready to install, I'll have to do a search on the rest. All I found was a front 4-pot Wilwood but nothing for the rear. I'll have to check on K Sport and D2. Other than still suspension bushings, the suspension remains pretty stock.

 

Energy suspension has bushings or then: https://www.prothanesuspensionparts.com/82018

SPC/Eibach have some upper camber adjustable ball joints if needed

 

Yeah, a lot of this stuff I've seen. Most of it I will get. Found the K-Sport brakes - $4,200?! Wow, that's a tad stiff. Wilwood will be my option. I just have to do a long more research to figure out how far I want to take this. I want to make sure I have the right strategy for the build and then start it.

 

maybe not worth to get the most expensive kit - they have some selection

 

So based on the direction I want to go, do you suggest P28?

 

Hondata

https://www.hamotorsports.com/s300-boost-package.html

 

Thanks, I'll definitely look into this.

 

I'll give you a solid and complete answer to the original questions. You'll understand much better after this:

-your car has an h23a1, not an h23a. the h23a is a JDM vtec motor from the accord SiR.
-a p28 is just a stock ecu for a d16z6 SOHC VTEC civic. People telling you to "just get a p28 and tune it" are being slightly ignorant and not really giving you any correct information at all, except the fact that you need to buy an ecu in order to tune your car.
-prelude ecu's are not tuneable. that is why you need to swap to a different ecu, a tuneable ecu. p28's are one of the many that can be tuned.
-all tuneable honda ecu's need to be modified physically in order to be tuneable. The modification methods are slightly different depending on which tuning platform you decide to go with.
-chipped ecu's have a physical chip added that is reprogrammable. These can be tuned with Crome software, or a select few others. There are free versions of these different softwares, but the free versions do not have datalogging. You need to pay $150 for a license to enable datalogging. Chipped ecu's require the purchase of several other hardware components for chip burning, emulation, and datalogging. Unless you're able to find a tuner willing and able to tune a chipped ecu and already has all the hardware.
-socketed ecu's have male pin headers added where a chip would normally be added, and are used with systems that add an entire circuit board to the ecu instead of just a chip. Hondata and Neptune are the two main systems for this setup. Software is free for these, the hardware is not. They are fairly pricey, but have almost limitless options for what you can adjust and expand. Even things like boost control, nitrous control, multiple auziliary inputs and outputs, failsafes, security, and so much more. After buying the main board, you do not need to buy any additional hardware.
-once modified, ALL tuneable ecu's are identical and do not have a name anymore. They are simply different by what features they have or lack. Like VTEC, IAB, boost control, knock sensor board, etc. These are all things you can add to them. Which means a p06 (non-vtec ecu) is completely identical to a p28 (vtec ecu) if you add the vtec conversion components to the p06 board.
-NEVER NEVER NEVER drive the car on a basemap you download somewhere or get from someone else. Basemaps are basemap, NOT tunes that could ever be expected to reliably run your engine. Your car will ALWAYS need to be professionally tuned after installing the tuneable ecu, and again if you make any changes to the engine setup. I can not stress this enough, especially if you plan to actually build a motor for your car. You can NOT just download a map and make a couple small tweaks and expect it to run right. It will blow up. Almost guaranteed. A professional tune is absolutely crucial.
-Do not buy ANYthing for an ecu until you talk to your tuner. Which means the very first thing you need to do is find a reputable tuner to have tune your car. Then ask THEM which tuning platform you should buy. A tune is only as good as the tuner. If you cheap out on the tuner and tuning fees, chances are you'll spend a hell of a lot more in repairs shortly thereafter. And a tuner can only provide a quality tune if you supply quality hardware that they are familiar and experienced with.

lastly, no, you do not need a conversion harness. Your car is obd1, and all tuneable honda ecu's are also obd1 with the exact same pinout and plugs. A tuneable ecu will plug right into your car. As mentioned above though, a few wires will need to be added for vtec if you install an h22.

 

I seriously want to thank you for your time and explanation. With all I've ingested over the last few days, I revised my strategy. Going to swap the H23a1 to the H22 first and I am NOT going to go full build right off the bat. My plan was to get a JDM motor, swap the core for a fully built short block, but at this point I think I am just going to take on the auto/manual conversion and H22 swap. Once I get that stable and working, I'll pull that motor and work on the full build/tune. I feel that taking baby steps would be much better that taking on an entire complex build; it will cost more in the long run, but I think that if I come across issues they will be much easier to diagnose - being new to Hondas I am wanting to get to know them intimately.

So with that said, if I were to pick up a JDM H22, it's pretty much just following the guidelines from most common H23a1 to H22 swaps and then I should get a P28 to run the H22/VTEC, correct?

 

I think you are on the right track now, and what MotoXXXman said is a solid basis to understand the difference in ecu's and tuning ability.

As he said, tuning many chipped ecu's requires burning a new chip each time you want to adjust the tune.

Personally, and like Timik suggested, I would go with a Hondata setup. The S300 is an excellent tuning system, and can be tuned in real time via USB, even easier than most of the OBDII based systems that Subaru tuners use. Personally my Prelude I run S300, and have a wideband O2 wired in direct for logging and tuning as well. Much easier than the Romraider/ Tactrix setup on my old WRX.

The Hondata still starts off as a board that goes onto a modified stock ecu, be it a P28, P72, P06 etc. The P06 needs to be set up for vtec use, but most all suppliers that sell Hondata setups do this for every ecu, and just sell them as a VTEC ecu, so P06 or P28 makes no difference. The P72 will have the ability to run the IAB butterflies in the H series manifold, so if you want that to function, it may be the way to specify your order, but might cost a slight bit more. Personally I never used the butterflies, and now run a fully gutted manifold so have no need anyways.

The 3 most well known vendors for a reliable Hondata and ecu setup in my mind, and alphabetically, are... HAMotorsports, KSTuned, and Xenocron.

You should be pretty simple on a swap from H23A1 to H22. When I did the swap on my 93, I already had the vtec wires in the harness, just had to find them and connect properly to the new engine. I used the original distributor and coil from my USDM engine, instead of rewiring for an internal coil.

 

You guys are great, thanks a ton for the information.

Would you still suggest a Hondata setup for going just with the JDM H22 swap (NA)? I would prefer to have an ECU that has the flexibility to control the NA/stock setup and then move into the induction/built setup. I outlined this in my post above, I just don't feel comfortable doing a fully built-induction build right off the bat, I want to get to know the car. So would the P28 do the work of both roles as long as I got a tune for both? I assume that my H23a harness will NOT have the VTEC wires - that would just be my luck. I think for the coil all I need is the bracket and can use my existing pack. There's still so much I'm looking at.

 

Correct terminology is very important here. Yes hondata is the better platform that can do anything you could ever want it to do.
correct terminology: you want a hondata vtec ecu. Leave out the ecu code, that is irrelevant once it is converted to be tuneable with hondata. It is simply called a hondata vtec ecu.

 

Sounds good, so the P28 chipped seems the way I want to go.