Honda CRX Forum banner
1 - 20 of 27 Posts

·
Registered
Joined
·
500 Posts
Discussion Starter · #1 ·
Question on my MiniMe setup... How should I do it? I've heard of three ways:

1. RPM switch (cheap, doesn't sound reliable)
2. VTEC Controller (Sounds good, but also sound like it has limitations, i.e. fuel and timing)
3. P28 ECU from a 92-95 Civic EX/Si (Sounds very OEM and reliable, with benifit of plug and play and increased redline. Also from same vehicle the z6 head comes from...)

I've bought a z6 head from toxiclows, and want to do this install right with minimal hicups. OEM reliability/usability would be great. Although I've read two MiniMe swap articles,

http://crx.honda-perf.org/articles/z6swap/z6swap.html
(For a Z6 head onto a D16A6 block which said nothing about a controller/ecu or OBD1)

http://www.honda-tech.com/zerothread?id=554053
(For a Z6 head onto a D15B7 block which said to go with the P28 ecu, but touched on Controllers)

http://www.hondaswap.com/forums/index.php?act=Attach&type=post&id=162
(Has a basic wiring picture for a VTEC setup, not sure if it is compatible)

I would like to get some feedback from the Community, as advice from people who know stuff to a kid who wants to learn. The right way.

The head will be looked at by a machine shop when I get it, a valve job done, new seals, and probably valves. I'll do a waterpump, timingbelt and any other changes the same time as the head, with a D16Z6 timing belt and a D16Y8 headgasket. The motor has 185k miles on it, with decent (avg of 180 psi) compression, so I might be able to wait on rings and/or pistons. I plan on doing all of this during winter break as I am away from my daddy's nice garage right now, and after I have saved a bit of money.

Everyone's thoughts/personal experiance on going about this setup? Money hopefully won't be that big of an issue, I have a few months to save up. When I do this, I'll be sure to take lots of pictures and do a nice writeup.

Sorry for the long, long post, but I want your feedback! Thanks in advance.
 

·
Registered
Joined
·
1,705 Posts
Ok. Let me start off by telling you what you should not do. Do not do the RPM activated switch. All it does is activate the VTEC on your engine. It will not adjust the fuel maps for you. Your car will have VTEC, but it will not be running efficiently. I know from personal experience because I purchased a car that was rigged like this. The engine would sometimes run too rich or too lean because of the incorrect fuel maps.

I personally would use a chipped P28 ECU (or other similar ECU chipped to the same specifications. ie: P06 converted to function like a chipped P28). However, a lot of people use VTEC controllers with good results.
 

·
Registered
Joined
·
500 Posts
Discussion Starter · #3 ·
Alright, first reply with good info! Thanks!

How would the chipped P28 would be different from the stock P28? And is the P28 (chipped or not) a basically plug and play type deal? I see a few virgin P28's on ebay for 100-120...might go look at the junkyards first.

Thanks!
 

·
Registered
Joined
·
1,705 Posts
You'll also need an OBD0 to OBD1 conversion wire harness so that you can plug in the P28 ECU into your car's wiring. You'll also need to wire the connections for the VTEC. www.rywire.com has some excellent wiring solutions for OBD0 to OBD1 conversions.

As for your other question, a chipped ECU differs because it usually has a chip socket soldered onto the board. If you have an eeprom burner, you can burn your own fuel map programs onto a chip and then plug it into the socket on the P28 board. This gives you a bit more flexibility because it allows you to alter the fuel maps to best suit your application. Since a mini-me swap is a pretty normal swap, you should be able to find optimized fuel-map programs at pgmfi.org. (as well as tons of other information about the subject).
 

·
Registered
Joined
·
500 Posts
Discussion Starter · #5 ·
Ok, thanks for the rywire info. That should come in handy in the future.

To the P28 ECU, how would a MiniMe setup differ from the motor setup from which the z6 head came from? Will the P28 run fine in it's unadultered form for a MiniMe, given that the OBD1 conversion be done?

Sorry for being noob, but that's what I am. I really appreciate the help.
 

·
Registered
Joined
·
1,705 Posts
That question I cannot answer with certainty. The P28 was designed to run the D16Z6 in it's original form. I'm not sure if the fuel maps would be bang on. But from what I understand, it runs pretty decent with a base P28 ECU.

Another option is to keep the car OBD0 (so you don't have to buy a wiring harness), and run a chipped OBD0 PR3/Pw0 ECU (B16 ECU). Disable the knock sensor, and burn a P28 program onto it, and you're set.
 

·
Registered
Joined
·
2,592 Posts
bittles110 said:
how would a MiniMe setup differ from the motor setup from which the z6 head came from?
There are little variations with regard to the block - The 'Z6 uses a different timing belt tensioner and water pump, and a thermostat mounted fan switch versus the 'A6's coolant jacket mounted switch. The major difference is the head and that the D16A6 (4th gen EX/Si/4wd wagon) uses different pistons than the D16Z6 (5th gen EX/Si). The 'Z6 pistons have have more dish in order to compensate for the head's reduced combustion chamber volume. By putting the 'Z6 head on the 'A6, you will boost the compression to a little less than 10:1 (assuming you use the 'Z6 head gasket) which is greater than either of the motor's stock compression of about 9.1:1.
Strictly speaking, increasing the compression will reduce the motor's resistance to pinging and detonation (both bad things). Realisticly, Honda builds these motors with a fair amount of wiggle room in that respect, so a .9 boost in compression won't make the engine tear itself to pieces... If it really bothers you, just run 91 octane gas.
 

·
Registered
Joined
·
500 Posts
Discussion Starter · #8 ·
Thanks for the good info, guys! Whichever ECU I get will depend on the price of it, but keeping it OBD0 sound like the way to go for a nudget college student. However, with keeping the car OBD0, I ren into the problem of not having a ROM burner... How would you guys reccomend that I get access to one? Buying one is kinda out of the question at the moment, for financial reasons. Is there someone in the Community that has one that would be willing to help me out?
 

·
Registered
Joined
·
1,705 Posts
There are shops that can burn the chips for you. If you don't intend to be changing fuel map programs often, you don't necessarily need to invest in a burner. I know there are several guys on Honda-Tech that do this for a living. Check also with www.pgmfi.com.
 

·
Registered
Joined
·
500 Posts
Discussion Starter · #10 ·
Alright. I've been looking over pgmfi.com for the past hour or so, and have been reading a lot of good info there. Just for giggles, I searched ebay for the PR3, P28, and PW0 ECUs, and found them for around $100. On those same pages, however, were auctions for chips already burned... would one of those suckers work? At $15 a piece, I might buy one just to play with. Any words of caution abou that?

And some chips come by different names... JUN Racing, SPOON, "Performance Chips"... Do they really differ? Should I even bother with these?

I'll have to check out Honda-Tech as well. Thanks guys.
 

·
Registered
Joined
·
1,705 Posts
Be careful of the ebay "performance" chips. Most of them are just a program that dumps more fuel into the engine and makes it run rich. You should check around on pgmfi.org to see if anyone has done an optimized program for a mini-me. Don't settle for a cheap chip on ebay that's going to ruin your fuel economy.
 

·
Registered
Joined
·
500 Posts
Discussion Starter · #12 ·
Alright, I'll steer clear of those. I just learned last night that a coworker used to own his own Honda performance shop... very interesting. Can barely understand his Vietnamese-Engrish, but he sounds like he knows his stuff. I'll have to see if he can help me with the swap... maybe do it sooner than I thought...

Thanks for all of the replies, I will keep you guys posted!
 

·
Registered
Joined
·
1,480 Posts
Keep me posted on your fuel situation. Ive got a a6/y8 mini me that isnt running good and Im waiting to get a conv harness. Ive got a p28 but im not sure if I just want to stay obd0.

Ive been lurking in your mini-me threads and I hope you have better luck than I did!
 

·
Registered
Joined
·
1,480 Posts
Lmao, im not going to even bother with telling you my setup. It such an embarassment.

Its a y8....thats about it! lol

Ive got a stupid rpm activated switch, still running on pm6 maps. My timing is off(i think) and its making a HORRIBLE ratting noise (or something that sounds like it) at WOT. No one can diagnose it, or is willing to help for that much. Ive got a p28 and a y8 dist, but the p28 i need a conv harness and they are effing expensive,and the y8 dist is obd2a so I duno wtf im going ot do about that.

Yet im in china and my car isnt being driven, just turned over once in a while. So when I get home I either might fix my noise or go back to stock and get headwork done. I still have a supercharger waiting in my garage also so its just 1 huge downer for me because I cant fix it by myself and no one can help.

LMK how YOURS goes because youll prob have better luck than me,
 

·
Registered
Joined
·
500 Posts
Discussion Starter · #16 ·
Hmmm... the Honda guru I know from work says I can run my PM6 without modding it... does he know something I don't? I guess we'll find out when we do the swap....

Can someone tell me the difference between the Y8 head and a Z6 head? Aren't both called a MiniMe, and thus the same?
 

·
Registered
Joined
·
1,480 Posts
Both mini me's but y8 has a higher compression rate than the z6. Both are from different years of 'vtec' and bother come from different ecu's. Of course if anything is different on and engine you must compensate, so the y8 ecu maps are different from the z6 but both can be operated by a p28.

If someone else could shed some light, that would be great because I havnt been looking at anything mini-me related for a good 2-3 months now, and I wont be for at least another 2 more months. So im rusty on technical stuff. Yet those are the basic differences in the 2 heads.

I used to know the exact #'s for the compression but im sure honda perf has those.
 

·
Registered
Joined
·
1,705 Posts
daveb91 said:
if you guys want to stay OBD0 and dont have A/C you can use turboedit chipped PM6 to adj and run VTEC and you can also get your timing and fuel maps just right.
What happens if you have A/C?
 
1 - 20 of 27 Posts
Top