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Ok, so here's the deal. I have two DOHC ZC (non-VTEC) engines. Both unknown mileage, one sitting on my back deck with a dead cylinder (valve problem I think) and one happily revving away in my 1989 CRX DX.
I have been planning on rebuilding the one on my deck, full rebuild, for turbo. Vitara pistons, unsure of the rods, bore/hone, bearings, new valves/springs/seals, etc. But then I started thinking. I'm on a very tight budget for at least another year or so, a turbo is not going to be in the cards for a while, and I don't trust the engine that's in my car now (unknown mileage and all).
So I got to thinking...I could go ahead and rebuild the motor like I'm building it for boost, but just use high compression pistons instead of the Vitaras and have a temporary goal of about 160hp N/A for a while, then just swap out the pistons when I start making some decent money and can afford to get the right turbo stuff.
By now, if you've even read this far, you're thinking "jeezus dude, just DO it, why did you even make a thread about this? Its not some 400WHP turbo AWD J32 RHD hella-tyte JDM yo front end swap, no one fVkcin cares!"
Well here are the stupid questions already:
* Can I get them madhellasicktyte VTAKs on my DOHC ZC?
* If I rebuild the motor, will it be a feasible option to swap out pretty much just the pistons when I go boost?
* Will upgrading the valvetrain/8k RPM redline/HC pistons/VTEC/light PnP/tuning get me to 160hp or thereabouts, or could I expect more?
* Can I possibly do all this for a budget of about $1k? I'm doing most of the work myself except for the bore/hone.
If you have read this far, I salute you! If you answer in a derogatory manner, no butthurtz here, you've earned it!
That was the question, is there a head swap that would add VTEC? If there isn't, then fine, but I didn't know.
The DOHC is about 130hp stock, how hard can it be to make 30hp with $1k? Granted, I was hoping there was a way to get VTEC, I might have to lower my sights if I can't do that.
Its too bad I've got the black JDM sheep of the honda motors, I swear the next car I buy will have a US equivalent motor lol
There's nothing wrong with the DOHC ZC engine. Your goals are just lofty and almost farfetched. Also when you ask "Can I get them madhellasicktyte VTAKs on my DOHC ZC?" who is going to take you seriously? Now that we know that it was serious question, we also know that your experience in engine building is very limited.
My honest recommendation:
Going from my own experience, try shaving the head a bit to bump up the compression. If you already have the correct ZC transmission, swap out the final drive set with a USDM Si final drive set. This alone should wake up the car a good bit.
Doing these mods shouldn't hurt your turbo plan. Being that the DOHC ZC head has bigger combustion chambers, you may want to rethink vitaras. Check what your compression ratio would be at if you used that set up.
There is no easy way to just slap a vtec head on a dohc zc. I believe someone tried it and failed. There aren't a lot of all motor zc's that are monsters, you could put in a lot of work and money and not get to your goal of 160. Honestly if I were you i'd save a up a little more and just start building a little homemade turbo. DOHC ZC's LOOOVE boost!
The DOHC ZC was the only dual cam D series, so no options on Vtec. The PM7 pistons are one the highest stock compression pistons besides the D17 which are 9:6 or 9:7 if I remember correctly. The cams in the DOHC ZC are actually pretty aggressive cams believe it or not. I've seen countless people with dual cam ZC's have stock everything with decent budgeted turbo kit putting out 200 - 230.....some people maybe even more. If all you have is a grand to work with, I'd buy a intake, exhaust from header back, and a ZC or Si tranny. If you're lucky you can find both and do the hybrid tranny. The original stock ZC header is actually pretty large. I compared my DC header to the stock one and there's little difference in diameter from the stock one.......only benefit was that the DC header was about 5 pounds lighter, give or take a few pounds.
I agree totally with 24ten, it's a awesome motor.......not a lot of aftermarket love but it's a super fun peppy motor that loves boost. (if built and tuned right)...tuning is one of the biggest keys that people don't seem to grasp that is just as important as a good build.
There's nothing wrong with the DOHC ZC engine. Your goals are just lofty and almost farfetched. Also when you ask "Can I get them madhellasicktyte VTAKs on my DOHC ZC?" who is going to take you seriously? Now that we know that it was serious question, we also know that your experience in engine building is very limited.
My honest recommendation:
Going from my own experience, try shaving the head a bit to bump up the compression. If you already have the correct ZC transmission, swap out the final drive set with a USDM Si final drive set. This alone should wake up the car a good bit.
Doing these mods shouldn't hurt your turbo plan. Being that the DOHC ZC head has bigger combustion chambers, you may want to rethink vitaras. Check what your compression ratio would be at if you used that set up.
Ok, yeah I wondered whether the VTEC idea was farfetched. And I was trying to be funny about the "madhellasicktyte VTAKs" lol. Sometimes my humor doesn't come through the screen.
I did have the head shaved slightly, I'm not exactly sure how much they took off though. An Si transmission would be quicker through 4th gear but actually lower highway RPMs, is that correct? I have looked up what trans I have, but I honestly don't remember now, I know it doesn't have the intermediate shaft the ZC trans does, if I recall correctly its the regular CRX trans.
I'm not really getting what you're saying about the combustion chamber being larger on the ZC, are you saying vitara's would lower the compression too much? My basic goal here is to have a fresh, strong motor that I can throw 250hp-300hp at daily. Obviously I'm not going to accomplish that for $1k, but for the motor rebuild, what would you recommend?
So far I've been planning on getting:
ARP head studs and rod bolts
MLS head gasket
OEM bearings
Forged pistons (don't know what kind though, any recommendations?)
H beam rods (recommendations?)
Greddy timing belt
New water pump
Not sure what to do about the oil pump, if I can get away with the OEM original one I was thinking of that. Don't know much about oil pumps honestly, aren't they gear driven? Not a lot of wear?
Personally, with only a grand to spend i would just either keep saving your money or use it to open up the air flow. Everything you just listed will not give you any power gain. But if you don't want to do that you could get a nice P n' P which will run you around your price range. Stock oil pump is fine......if you rev out a lot then you may want to invest in some Eagle rods, they should come with ARP studs.......at least mine did. You don't need to spend extra dough on a Greddy timing belt kit, OEM is sufficient.
The usdm 86-89 Inegra used a D16A1. Although simlar to a jdm zc, there were numerous differences including pistons, cams, intake manifold, cylinder head and engine mounts
Ok true, but it's the JDM equivalent, i was basically getting at the fact that there's no way to make it Vtec. Some D16a1's did come with PM7 pistons, I forget the code for the other pistons. And according to AutoZone, the exhaust manifold on the D16a1 goes from the header to a single pipe then to the cat. I found that out the hard way when i was trying to replace my exhaust header to downpipe exhaust doughnut gaskets. They only show it needing one when the JDM ZC needs two........then again it is AutoZone. Not bad mouthing them, but there's just some things I won't buy from them. The intake manifolds have such slight differences, I don't believe there would be any performance differences. But you are correct good sir Deetz, I was basically giving incorrect info.
Personally, with only a grand to spend i would just either keep saving your money or use it to open up the air flow. Everything you just listed will not give you any power gain. But if you don't want to do that you could get a nice P n' P which will run you around your price range. Stock oil pump is fine......if you rev out a lot then you may want to invest in some Eagle rods, they should come with ARP studs.......at least mine did. You don't need to spend extra dough on a Greddy timing belt kit, OEM is sufficient.
The stuff I listed is more for peace of mind than to gain HP, although when I do build it for boost I was planning on around 250hp. I obviously budgeted a LOT more for that power goal than I did for just a normal rebuild...
What is the weak point on the ZC? If I can get away with running the stock pistons and upgrading the head gasket, head studs, and rods and bolts then that will save me quite a bit. Like I said, I'd like to be able to run 250hp without worrying TOO much about it.
Agreed with Vagitarian (*****y name by the way, love it). I bought my hatch ZC swap with unknown mileage almost two years ago and it sat for two years before that, it still runs like a champ. Routine maintenance and replacing the timing belt when you should will make almost any engine last forever. I had a H23 with almost 400k on it before it got totaled and all i did was a timing belt replacement and routine maintenance. Weak points on most Honda motors are the rods and rod bolts and the actual casting of the head.......there's alot of room for activities there. The angle valve jobs and a good P n' P. But you really won't feel the advantage of it without a good tune.......on a stock motor. Having a shaved head is a good start though, if I remember correctly you said you've had it done. That alone has bumped up your CR slightly.
Hmmm, lots of food for thought here. I guess I could just rebuild the head of the engine I've got on my deck and have that ready in case I blow the engine I've got in the car. I could leave the bottom end of the one I've got running alone and just refresh the head a little (burns some oil at high RPM but compression is good, so probably valve stem seals) and turbo that, and have a good engine waiting in the wings should something happen.
At the moment, its my only car, so I need at least some reassurances in case some shiza goes wrong.
The DOHC is about 130hp stock, how hard can it be to make 30hp with $1k?
If you dyno'd a brand new DOHC ZC you would probably make 110WHP, making NA hp is difficult and expensive. 50 WHP from an NA 1.6L (That's almost 50% on top of its stock output) is a steep ask.
I was doing a turbo build on my zc but im on an auto trans its not impossible to get an extra 100hp but its costly of 3800.00 i had forged pistons eagle h beam rods knife edged crank pm7 regrinds supertech titanium valves and retainers head shaved .8mm ported polished. And gained 230hp 195lbs at the wheels. 70mm b series throttle body. Dc sports 4-2-1 header aerospeed bomber exhaust..
DOHC ZC all motor options?
Granted, I was hoping there was a way to get VTEC, I might have to lower my sights if I can't do that. 
