ZC DOHC 1991 Hatchback Transplant - Epilog

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Someone bump this thread on someone else thread, I just thought to check it out. First thing I stamble upon on page one was port matching the tb/manifold and port matching intake and exhaust.

If your going to port match only port match one side or it will work againts you and loose on some serious tq. For example, Tb making the runner a little bigger is wise but to big will take negative effect. Only port match the intake manifold to gasket and don't port match the exhaust.

Your already done some serious head work and that's what the ZC needs. Port matchng everything else will kill the flow and might work against you. Also, You done a great job on this build and I think it's more of pribe that drives you. Excellent work, but you could have save some serious cash on engine management and cam gear.

The b16 cam gear work great with the zc and there about 50bucks. A chip p28 ecu or chip p06 non vtec ecu will be good enought and tune with crome. In my own opinion I know power goal is at 160. I really don't think you would see that or come close. Overall, great work.

good luck
 
Someone bump this thread on someone else thread, I just thought to check it out. First thing I stamble upon on page one was port matching the tb/manifold and port matching intake and exhaust.

If your going to port match only port match one side or it will work againts you and loose on some serious tq. For example, Tb making the runner a little bigger is wise but to big will take negative effect. Only port match the intake manifold to gasket and don't port match the exhaust.

Your already done some serious head work and that's what the ZC needs. Port matchng everything else will kill the flow and might work against you. Also, You done a great job on this build and I think it's more of pribe that drives you. Excellent work, but you could have save some serious cash on engine management and cam gear.

The b16 cam gear work great with the zc and there about 50bucks. A chip p28 ecu or chip p06 non vtec ecu will be good enought and tune with crome. In my own opinion I know power goal is at 160. I really don't think you would see that or come close. Overall, great work.

good luck
Power goal is/was 150 hp (as documented in thread) and judging by the way it runs now, against the way it ran with the D16A6. it's there. Stock, the new motor is rated @ 135 hp with stock intake, ribbed air induction tube plus stock filter and air box, and stock exhaust. 15 more hp puts it at 150 - the bolt-ons' it has should just about gain that without taking into consideration the porting, larger TB, and compression ratio change from stock ~9:4-9:5 up to 10:1 .

Intake manifold and head were port matched to the gasket. Exhaust side of head was matched to gasket. Header was centered up over gasket (using custom bushings - documented on thread) to match. (see post #3 for header installation and matching detail and post #7 for intake and TB port details)

Aftermarket B16 cam pulleys do work on the DOHC ZC with a little modification - documented in the thread. Yes, they were $60.96 delivered to my front porch as documented in thread.. (see post #20 for cost breakdown of build and post #7 for machine work on the pulley's)

Appreciate the insight into porting, not really sure where you're coming from with that. Maybe you skimmed past that section? Why even mention making the intake runner larger than the TB? Matching is the key and that's what was done. Don't port match exhaust? WTF? Machine shop did all the work on the head reference cc'ing the combustion chambers, milling to set compression ration to 10:1, port to gasket matching of head with cleanup and 3 angle valve job. I did exhaust manifold "Fit" matching and TB to intake manifold matching as documented.

P29 map/chip runs great in the P06 ECU platform.- but, it's still not perfect - feels a touch lean after jumping on it hard on the idle down. Next major upgrade will be a Hondata S300 and tune.

What serious cash can I save on cam pulleys and engine management?

Appreciate the compliments! :)
 
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I like to point out problems that don't exist in other peoples threads too. :)
Yeah, but we expect that kind of shit from you.......just "look the other way" ya know......don't ask, don't tell.

My favorite part is the "Don't match exhaust ports" section, followed a close second by the "Don't make the intake runner larger than the TB" commentary.

I deleted the place where I mentioned porting and tuning engines for the past 40+ years...... WTF, the cat's out of the bag now. :)

Kinda depressed now, knowing it'll never come close to 160 hp.

On the brighter side, already thinking aome ARP studs and a .031 Commetic head gasket for 10.5:1 when I do the S300 upgrade. Uh oh!!!!
 
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Let me know when you hit 150hp and then I will apolize for my compliments.

I didn't realize, Hondata, Neptune, ectune, Crome, Uberdata, Turboedit, and whatever software was around 40 plus years ago,(Hint-Hint). Base with my experience and other builds with similar setup that you have you would have to be as close to 12cp and alot of dyno time. I was not hating, infact I thought your build was more of a "pride" rather than "hp" which most younger kids doen't understand and doen't appreciate.

If you took it the wrong way then I apologize, I'm an engine builder and a tuner with alot of experience with different setups. Guy's in the shop invested alot more money than I seen you spend and at the end 145hp is more than doable.

Show me what you got and I will personally call you (if number is given) and I will apologize if I'm wrong.
 
Let me know when you hit 150hp and then I will apolize for my compliments.

I didn't realize, Hondata, Neptune, ectune, Crome, Uberdata, Turboedit, and whatever software was around 40 plus years ago,(Hint-Hint). Base with my experience and other builds with similar setup that you have you would have to be as close to 12cp and alot of dyno time. I was not hating, infact I thought your build was more of a "pride" rather than "hp" which most younger kids doen't understand and doen't appreciate.

If you took it the wrong way then I apologize, I'm an engine builder and a tuner with alot of experience with different setups. Guy's in the shop invested alot more money than I seen you spend and at the end 145hp is more than doable.

Show me what you got and I will personally call you (if number is given) and I will apologize if I'm wrong.
Dude, you came in here spewing a line of crap a mile long. Honda engineers don't trek on down to the neighborhood import speed shop and hang out with the boys to measure horsepower and trade street racing stories - they measure horsepower at the flywheel using SAE specifications to be on a level playing field with other manufacturers.

My build is spec'd around SAE horsepower ratings for now. You, for some reason want to compare SAE to WHP ratings which yield very different results - many times wildly different results.

Equations: Dyno Correction Factor and Relative Horsepower

The porting dialog is absured and indicates you didn't even read the thread:

"If your going to port match only port match one side or it will work againts you and loose on some serious tq. For example, Tb making the runner a little bigger is wise but to big will take negative effect. Only port match the intake manifold to gasket and don't port match the exhaust."

^ Doesn't look like anything I would consider to be experienced.

Comments on money savings are again representative you didn't even read the thread:

"Excellent work, but you could have save some serious cash on engine management and cam gear.

The b16 cam gear work great with the zc and there about 50bucks. A chip p28 ecu or chip p06 non vtec ecu will be good enought and tune with crome. In my own opinion I know power goal is at 160. I really don't think you would see that or come close. Overall, great work."

It's running a socketed P06 A01 ECU with tweaked P29 map and $50 pair of "eBay special" modified cam pulleys. For a mild build on a DD, that's the most cost effective way I could find. While the B16 cam pulleys (THAT YOU RECOMMEND FOR THIS ENGINE) do fit the ends of the camshafts, they are not "PLUG & PLAY" compatible as you suggest and require machine work - they don't "Work great" on the ZC out of the box - the offset is incorrect.

Translate: 125 WHP as measured on any given summer day at the corner speed shop will net out in the neighborhood of 150+ SAE hp. Conversly, 155 SAE will Dyno (on a chassis dyno) from 15-22% loss or ~125 WHP. This doesn't account for atmospheric and temperature corrections in the SAE specification J1349 which will almost always correct in favor of even higher SAE ratings when compared to the neighborhood speed shop measurements. This build will never see 150 WHP, even on a nice winter day. I wouold estimate it to be ~120-125 WHP and that's a guess. That would be on a 70 degree day with low humidity.

These engines don't run gear drive on the camshafts, they use pulleys and a toothed belt commonly referred to (outside the world of import lingo) as a Gilmer drive setup.

While I can appreciate your commanding knowledge of Honda lingo, import vernacular and name brands in general - please read thread before commenting.

Have a great day! :)
 
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Haven't update this in a while. Been driving car. Still running good, engine has ~2200 miles on it now.

Did second oil change over the weekend. I need another filter wrench as the expanding band type which is my favorite won't fit the filter on the Honda. The other one is a 3 jaw clamping type and it comes just short of smashing the sides of the filter in when tightening it up - is does deform the filter when removing old one.

Car had gas vapor smell in cabin, so after the oil change I cranked it up to go on safari until I found the source of the smell. I figured it was the high pressure feed line coming out of the tank as I has already looked around the fuel filter on the firewall and the fuel rail feed line up to the fuel rail. Figured I would have to drop the gas tank to fix it.

With hood up and engine running the smell was strong. Looked around the filter area afgain and all was well, so I followed the path of the fuel across the fuel rail and noticed the runner on #1 cylinder had a wet spot on it under the #1 injector. Turns out the upper "O" ring on the #1 fuel injector had a tear in it. Probably damaged during installation would be my guess. I pulled an "O" ring off of a spare injector and put it on #1. When I reinstalled it I put a dab of white grease on it and it slid into the fuel rail nicely.

Ran old alternator belt when I did the swap as the fairly new one from the D16A6 won't fit the ZC. I picked up a new belt a while back and decided to install it while under the hood. Good thing I did. When disconnecting battery the negative terminal was found to be loose. Loosened the top adjuster bolt on the alternator and it flopped around - bottom bolt had fallen out. All I can figure is I forgot to tighten it when it was installed. Fortunately, the ZC came with an alternator attached, and I kept spare parts from the D16A6. Had one in the spart parts box along with a locking type nut.

It's torqued up now and belt doesn't squeak anymore when engine is first started. Battery terminals are tight.

Idle is still a little high and TPS needs to be adjusted or replaced. I'll deal with that this upcoming weekend. Prolly outta re-torque the head too.

The DC Sports stainless header has no support brackets on it. I put it on almost 2 years ago and it's fine. But, really should have a support bracket somewhere at the rear of the engine just ahead of the catalyatic comverter. I ordered some 304 stainless steel flat bar - 1/8" x 1 1/2" x 4' and 1/4" x 1 1/2" x 4'. Going to fabricate a bracket that bolts up to the holes on the back of the engine block that hold a half-shaft bracket - as they are unused in the Civic Si.

The polyurethane exhaust hangers are holding up well.
 
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Were there any issues with axle fitment?

E
No axel fit issues. I used the stock Si tranny. Gearing is right, It had a fresh rebuild on it about a year before I did the swap and it bolts right up to the ZC. Same axels used too. ZC block & D16A6 block are essentially identical.

Seems the Si tranny is a version of the L3.
 
Got up @5:30, did my bible readin and finally read through the WHOLE build..

MAN.. Nice job! I was getting nauseous during the wiring section though. I hate wiring.
I'm attempting a b18 swap into a HF and am porting the head this weekend. (both ends, with manifolds) It's my first fuel injected swap of a different model engine. You sir, have given me more confidence in pushing myself past barriers.. Thanks.
I've done plenty of the older carbed swaps of the 70's and early 80's and actually have a 78 1200 that I built up the motor with side draft and close ratio trans, but now thinking of dropping (fabbing) in a d16a1 into her. (if I ever find the time..) There isn't any emission regs here yet, so one could get as nutty as one wants.

If you don't mind, Could you pm me or post the place you used for the ECU's?
There are tons of fly-by-night ecu places on the net and was wondering if you purchased new or used and configured/mapped it all out on your own.
I could probably do the soldering myself, but I haven't soldered PC boards since the early 80's avionics classes.
It might be better for me to pay someone else to do that..
Grace to you, and Happy Thanksgiving.

E
 
I picked up a couple of used ECU's on eBay. I used their feedback as a guage for ECU purchases. Looked for current feedback on ECU sales for the 6 months prior to when I was buying.

I also bought the Winfab Tuning P29 modified map chip set and socket. As posted upstream, I did all the ECU modification work myself. I've done many years of electronics work, soldering and kit building - not bragging, suggesting if you haven't soldered in a while maybe have it done somewhere to save some grief.

Glad it had a positive effect on you. Confidence with the wiring is something that came to me from years experience with wiring, electrical and electronics. As in 40+ years. But really, it's not that big a deal. There is much data out there online for a build and that's the important part with wiring and troubleshooting - good data, good schematics. I found Helms online - probably posted a few of them in the thread. I know during and after the build, I burned a cd or two for other members and mailed the data to them for the 1991 EF.

With many of the builds (swaps) I've read through, there is troubleshooting before and after start-up. Numerous CEL codes and fast idle, etc. Many times, troubleshooting necesary just to get to start-up. Hopefully, your build is a project car and not your Daily Driver as that puts it in a different perspective for time.

Good luck with it and Happy Holidays.

Welcome to HondaSwap Forums - there is a pretty good crew on this site.
 
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Tool Time

Tool Time at my shop today. Getting ready to fabricate and weld up a bracket on the 2-1 collector section of the exhaust header. It will be removed for some of the work, which means wrestling with the spring loaded bolts at the header/exhaust system flange. Lot's of fun! I've done it a few times over the years and am getting better at it using various prying devices to compress the springs when putting the nuts on, but they will slip every now and then with the bolt flying out at near mach one. When I did the swap and hooked things up, I thought about a custom made tool to use that was designed specifically for the job.

So, in anticipation of breaking and making the header/exhaust connection again, here's what I came up with.

18" in total length, made from 3/4" x 1.5" aluminum flat bar. I used that because I had a piece available.

Took a step drill and opened the hole to 5/8" to accomodate the bolt head. Works real good and springs can be fully compressed with one hand on the tool leaving the other hand free to install washer and nut on the opposite side of the flange and not end up with a face full of high speed bolt in the process.

Exhaust%20Flange%20Spring%20Tool%201.jpg


Exhaust%20Flange%20Spring%20Tool%202.jpg


The tool rests against the steering rack when in use as pictured below. There are 2 holes in the tool as the flange sits on an angle and the bolts are not the same distance from the steering rack. Driver side is closer to the steering rack or higher than the passenger side.

Exhaust%20Flange%20Spring%20Tool%203.jpg
 
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ECU Modifications Post #7

Updated Post #7 showing modifications to the P06 ECU chassis to make the mounting provisions fit the 91 hatchback.

ECU%208.jpg
 
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