I've searched up on this but some questions are still unclear......what differences are involved in installed a d16y8 or a d16z6 head on a d16a6 block? which one is better/cheaper? are both simply just the matter of bolting them on like the stock head and wire vtec and go? any problems that usually happen and how reliable are these swaps???? thanks so much for any help and sorry for the flood of quesions

 

did you try the archived search for mini me? youll get a

Blaze

 

did you realize the search function is disabled.


heads bolt right on. use a z6 or y8 gasket.
z6 head flows better.
y8 cam is better.
wire vtec and run.
pretty reliable i guess?

 

sounds good the motor can be ran without hooking the vtec up correct?
I might have to get someone else to wire the vtec cause I'm not much good when it comes to anything thats not hands on. anybody know what kinda hp/tq gains I could expect? thanks for the replies so far

 

If you're sticking with the A6 block, there are some things you should be aware of.

Compression Ratio: Using the Z6 head on a A6 block will yeild a CR of somewhere around 10.2:1, while the Y8 head will bump that up to approximately 11:1.

The Z6 and Y8 gaskets are of the same design, but the Y8 is thinner (increased CR). Either will work for a mini-me set up.

Timing Belt: The Z6 and Y8 t-belts are the same, but the A6 is different. When doing a mini-me swap, just use the timing belt meant for the head to ease confusion. (ie Y8 head, Y8 t-belt...)

Differences in Heads: The Z6 head porting is very similar to the A6, and the same goes to the combustion chambers. This head flows very well, has decent cam profiling, but the A6 distributor won't line up very well to it. The A6 dizzy will work, but you'll have to do a little bit of modification to the A6 dizzy (easy).

The Y8 head has a different style of combustion chamber which results in the higher compression ratio, and I've heard it is a more detionation resistant design. The Y8 cam is much more aggressive than the Z6. The A6 dizzy bolts up perfectly to this head - but there is one downside, the intake ports are designed to promote a high amount of swirl... This results in a great A/F mixture, but poor breathability. Simply put, the Y8 head is a HORRIBLE flowing head.

Power: Since we are talking about mini-me's, the power you'll get HEAVILY depends on how you tune it. By just sticking with your stock ECU, and throwing a cheap VTEC switch, you're mini-me isn't going to be much better than your old A6.
The best we can do is compare the stock HP/Torque ratings.

The Z6 puts out approx 125 HP, and 106(?) FT-LBS of torque.
The Y8 puts out approx 127 HP, and 106-7(?) FT-LBS of torque. (ratings for both motors are at the same RPM)

- I'm too lazy to look these up right now, but the main difference is only 2 HP. I think the Y8 has MUCH more potential than just 2 HP over the Z6, to unleash that, you'll only need a port and polish job. That should put it around (guessing) 10 HP above the Z6...

Last but not least, VTEC: You have tons of options for VTEC activation. I've tried most of them, so I'll only list the ones worth doing.

Z6 SETUP:
OBD-1 Conversion
ZDyne VTEC ECU Conversion (they have the actual Z6 maps)
V-AFC (using stock PM6 ECU, don't use 88-89 PM6...)

Y8 SETUP:
OBD-1 Conversion w/VAFC
V-AFC (considering you have a '90-91 PM6 [Si] ECU)
Or, some sort of OBD-2 Conversion (never seen this done before)

Despite the 2 HP differences of the motors, the camshafts are VERY different. The Z6 ECU is not nearly enough for the Y8 head - VTEC kicks in too early, not enough juice for the VTEC lobe, etc etc. Like I said above, the only reason the Y8 is 2 HP more than the Z6, is due to the wierd intake porting.

Both are very good heads - either way you'll get increased gas mileage, and increased power. Tuning is the biggest factor for a good mini-me setup.

Oh yeah, to answer your question above - YES. Either head will run just fine without VTEC. The VTEC is just an additional intake cam lobe that activates at a given RPM. When it's not hooked up, you'll just be running on the smaller lobes - which result in less power. But it will drive with no problems whatsoever.


[Modified by MrTodd, 8:40 PM 4/3/2003]

 

Wow thank you very much you cleared up alot for me, I'll also be adding I/H/E to the swap so I should get a decent jump in power......have you ever been to the track with your car? if so what kinda times were you running? thanks again for the help also will this increase my redline? from 6500?


[Modified by H.crx-si, 4:05 AM 4/4/2003]

 

I haven't had the time to head to the track. Even if I did, my time's would be about 1 second lower than everybody else's because I live in a high altitude state.

As for the redline, the Z6 head's natural redline is 7200 RPM's. The Y8's is 6800 RPM's <--- This is due to the weak Y8 bottom end(bearings mostly), the Y8 head is just as stable as the Z6.

With both the A6/Z6 combo and A6/Y8 combo, you'll be safe revving it up to 7200 rpms. If your A6 block is a little tired/old, I would try not to bring it past 7k on daily driving. The reason why I used a Z6 block is because it has the highest natural redline of all USDM D-series motors. I couldn't trust my old A6 block to run at 7500+ RPM shifts.


[Modified by MrTodd, 9:37 PM 4/3/2003]

 

ok one more question and I'll shut up haha
does a d16z6 head on a d16a6 block both totally stock with vtec wired to a cheap vtec engage switch compare to a zc when it comes to power? or does the zc usually put out more power? I'm thinking 125-130hp from the mini me and 130hp from the zc both to the flywheel or course.... so I'd imagine it'd be a close race?basically I want my mini me with I/H/E crx to beat a zc powered crx


[Modified by H.crx-si, 5:32 AM 4/4/2003]

 

There is some info there that isn't correct. A A6/z6 mini-me compression ratio is actually 10:1 and a Y8 is 10.3:1. The Y8 cam is slightly more aggresive, not much. If you don't hookup VTEC you won't have much power over 5k. IF you don't hook up VTEC you might as well stick with your A6.

Also, from what I've read the y8 doesn't flow as well on only the topend only. The swirl actually helps with low and mid range power. Also both engines use a 7200 redline.

As far as mini-me power goes, it will have to do with your tuning and ECU. My a6/z6 mini-me put down 122 hp to the wheels with intake and headers. I was also using a Y8 cam and a obd1 setup with a P28. I've seen a6/y8 mini-mes put down from 116-130 whp. It depends on your ECU and how strong your bottom end was. Here are the charts if you want to check them out,
http://www.norcalcrx.org/dyno/d.html

 

Damn after looking at those charts, the mini me swap dosn't look to be worth it whatsoever......the guys running stock d16a6 with I/H/E are almost putting out the same numbers as the mini me's.......

 

What do you mean? How much power did you expect to make? None of the d16a6s are stock.

 

d16a6 15.1@88 mph a6 with z6 head and msd switch 14.6@92 mph nuff said!!!!

 

I'd take my mini-me over a regular A6 any day. Just love that extra "kick" from VTEC. If your motor is in good condition there should be no problems when swapping on the head. I swapped mine at 75,000 miles and it's been running good for the past 8 months. As for cost, I paid 100 bucks for my Z6 head, sold my old head for 85, and paid about a 100 bucks for gaskets and a new timing belt. I paid a guy $50 to change my timing belt (I couldn't get the crank pulley off) and did the rest of the work myself. The only problem I encountered was getting parts for the swap. The parts guy at Honda kept getting confused and ordered the wrong parts. I had to keep going back to get the right ones. But I did get my t-belt at half price because of that

 

what did u have done to your stock d16a6 to pull a 15.1? From the charts I seen the a6 block with a z6 head was getting 116hp and 102lbs/tq with I/H/E and a vtec controller where a stock a6 with I/H/E was pulling 110hp and 104lbs/tq.........6hp and -2tq to me that does not look like it's worth while one bit plus by the sounds of it getting the timing right is a total bitch.....the more and more I look at this swap the less positive it looks.....anyone got anything to positive to say about this swap?

 

The bottom end of that mini-me has 275k on it. And that's a Y8 head with a PG7 ECU. The car was also using the stock d16a6 intake manifold, which doesn not go real well with the Y8 head.

My car put down 118 and 122 whp with different cam settings. I did not tune the engine to make that power. I'm also running the stock exhaust which I'm sure is sucking some power. My air filter was dirty and my plugs were old. With new plugs, a clean air filter, and some tuning I'm very pretty sure I could have broken 130 whp.

You're comparing a very strong A6 to a not super strong mini-me. It's not a fair comparison. There are SO many different ways to do the swap you can't just look at one dyno chart and make a judgement. What did you expect anyway? A mini-me is not a b16. A mini-me is in the same class as a ZC, d16z6, and d16y8. It should be a faster by than a d16a6, but not by a huge amount.

Also peak horse power and torque numbers mean crap. It's all about the amount of area you have under the horsepower and torque curves.

Also, getting the timing right is not a total bitch. It helps if you can get the car on a dyno, but it isn't that hard to figure out. I was very happy with my mini-me, it didn't cost a arm and a leg, it got great MPG, it was fun to play with, and it made good power. I was very happy with the swap and don't have any complaints.


[Modified by Noahk, 5:06 PM 4/4/2003]

 

Ok I wasn't aware of the other problems with that dyno....that totally changes things......I wanna do this for sure I have 240,000kms/150,000miles on my stock block so I'm gonna slap on a low mileage head and intake manifold and see what I can do.......I got beat by a 2000 v6 cougar 5speed with intake tonite by half a car I need this head to teach this friend of mine a lesson lol

 

Do a compression test on you current engine first.

 

motor was in a 91 hf with an si trans of course,also had a good ecu and cold air intake,header,and 2 1/4 exhaust.but once that vtec cam comes on there is no comparison to the stock a6 head.pulls much harder from 4000 to redline!!!!

 

does anyone know where these heads are available I've been looking locally with no luck as of yet......I live in Halifax Nova Scotia so I'm sure I'm quite a ways from most of you people

 

 

i love my mini me si block with 205k miles on it and a 97 ex head with the y8 head gasket all i have is intake exhaust and FPR and VFAc runes nice :0 i think its best swap for $$