how to make 1st gen teg head work in my 91 si?

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pworrelcrx

pworrelcrx
i have a dohc head of a d16a1. it's a brown valve cover. what must i do to make this work in my 91 crx si?
 
Wow...youll be ucky to get a answer on this. I know a D16a1 head will work on a d15a3....early crx civic mpfi engines. I also know that ive taken a d15a3 head gasket and placed it on a 1991 d15b2 head. Everything lines up, all the ports, bolt holes, oil jet...all but the 2 bolt passages at the back of the head on each corner. they have to be machined out to line the ports up. Using that head it seems youll have a issue with a timing belt. Search fo Hydra dohc on google or visit red pepper racing.com. There was a guy on there that mated a d16a6 on a d15a3 block. If he did that perhaps it can work the other way around to. Good luck.
 
not all that easy, but it can be done - this is the best write-up i have seen on what needs to be done:

www.thezcr.com - Putting a zc dohc head on an A6 block.

Thats not the same as the head im referring to. The Zc im talking about is the same as the D16a1's. Those are the head the 1st gen crx guys use for hybrids. They line up with the d15a3 block perfect. Ive had a d15a3 headgasket on a pm3 head from a civic. it lines up almost a hundred percent. The two backside bolt holes on each side are the only thing i could see would have to modded. I think the best thing to do for that problem would be to use a 88 integra head gasket and place it on the sohc d block. Scribe what doesnt line up...the two holes. Then place a sohc D headgasket on the integra D16a1 head. Scribe that...then use a rotary tool on both the head and the block to even up the differences. I wanted to try it. As far as a timing belt..who knows what you would need. For the D16a1 head on a d15a3 block you have to use like a 91-92 prelude timing belt but i dont know if it would work with this. Be creative, be the first on to do it. The head the guy in the video used is from a 2nd gen 88-91 ZC. the 88-89 integra d16a1 or Zc of that year would probally be easier. Do it!
 
You do know that the DOHC ZC is the JDM equivalent of the D16A1 and that D15A3 is a completely different animal than the engines in EF Civics
that is correct - although the heads have some minor differences on the outside of the castings for mounting timing belt cover, distributor, cylinder sensor and intake manifold, they are pretty much identical - the 86-89 USDM Integra D16A1 and the 84-95 JDM DOHC ZC engines all have the same head bolt pattern, water passages and oil drain back holes - they all use the same head gasket - the 88-89 USDM D16A1 is really close to the same as the 88-95 JDM DOHC ZC head with the only differences being in the bolt hole locations on the end for the timing belt cover and the A1 has 2 additional intake manifold mounting bolts - due to casting difference for the timing belt cover, the A1 uses one longer head bolt - the 86-87 D16A1 heads and the 84-87 DOHC ZC heads are identical and only differ from the 88-89 D16A1 heads by having different distributor and cylinder sensor mounting bolt hole locations
 
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You do know that the DOHC ZC is the JDM equivalent of the D16A1 and that D15A3 is a completely different animal than the engines in EF Civics, right?

JLI is pretty much the man when it comes to ZC stuff.


Yes i used to own a 1st gen. It ran off a ported head, 1991 accord 240cc injectors, a b&m FPR, Msd ignition, dual valve springs, 87 si transmission, 2.5" custom exhaust, 4-2-1 chikera header, all running of a 87 PG7 ecu.

There were 2 different d16a1's. A brown top vacumn advance. A black top electrical advance. There are zc's that are higher powered versions of those engine. They come in either brown or black top.Dont forget the D16a8 and A9 EDM versions ok. The original Zc was nothing more than a EW4 with a DOHC head thus the HYDRA. I know the ew/d15a3 is different from the 88 and up d series. Noobs think they are the same. In 1986 honda changed the block stamp on the ew's to d15a3...they also changed the electrical connections in 86 as well. That why when doing a ZC swap into a 85 CRX you need a 86-87 integra harness, because alot of the shits plugs have to be depinned and move to the crx harness. A crx harness will work best on a browntop ZC if you use the crx thottle body with the ZC. This being because the TPS on the ZC throttle body has the new style plugs.

I sir am no noob...maybe to this forum but not to hondas. Ive own a 92 CB7, a 85 CRX si, 1991 Civic, and others. Ive done engine swaps, head swaps, head porting, tranns swaps, cam swaps, cam gear swaps, gonna try the MPFI swap here shortly. I sell parts for hondas...therefore i compare alot of different parts with others from other cars.
 
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Then you should already know your answers. :)


...but ill never stop learning. Asking ???'s works good. Doing yourself works better. Breaking shit because you didnt know is the best teacher...high price way of leanring but you dont forget stuff after you eat the cost of some parts.;)
 
...on a cadaver, with a teacher looking over their shoulder, and hours of book work every night. When doctors make mistakes on living people, those people tend to suffer serious damage or even die.


Musta sucked in the early days.....oops i cut the wrong thing again Bob....what do we do now? Shove it back in a sew him up Jack. Thats the thrid one this week.
 
You're missing the point.


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There were 2 different d16a1's. A brown top vacumn advance. A black top electrical advance. There are zc's that are higher powered versions of those engine. They come in either brown or black top.Dont forget the D16a8 and A9 EDM versions ok. The original Zc was nothing more than a EW4 with a DOHC head thus the HYDRA. I know the ew/d15a3 is different from the 88 and up d series. Noobs think they are the same. In 1986 honda changed the block stamp on the ew's to d15a3...they also changed the electrical connections in 86 as well. That why when doing a ZC swap into a 85 CRX you need a 86-87 integra harness, because alot of the shits plugs have to be depinned and move to the crx harness. A crx harness will work best on a browntop ZC if you use the crx thottle body with the ZC. This being because the TPS on the ZC throttle body has the new style plugs.
i know all of that, but that doesn't change the fact that they all use the same headgasket and installing the D16A1 head on the SOHC block is the same as installing the ZC head on the SOHC block - as for the original question, using the "brown" D16A1 head would present other problems besides just bolting it on, since it has different distributor mounting holes and the electronic advance distributor won't even come close to bolting onto it, not to mention that unless you changed pistons, it wouldn't have much compression - by the way, don't forget the D16Z5 DOHC engine
 
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That's the best way to ensure that nobody gives a damn what you post.


Are you serious. Some of you guys on these boards really do need to relax some. As far as negative rep.....whoopie doo...so what nobody cares what i post. I care, if you dont so what, i the next guy dosent....so what. If you post something intersting to me I care....why cause you took the time to post. As far as me taking my immaturity to honda-tech well how mature would it be to keep to yourself. If I offended you then im sorry...if not im still sorry, sorry you cant take a joke. You know thats the second time youve told me that ive failed to miss the point of a post. Its also the second time you have failed to explain yourself. remember my dyno post of the si cam swap, yeah you did it there. If youre gonna point your finger at someone at least tell them why. Thing is i was only trying to help this guy and you jumped in questioning my knowledge of hondas. Maybe you sir offended me. Did I negative rep you?? No i didnt cause i maturally waved your ever so small attempt to ruffle my feathers off, but really if you dont care what i say them ignore me. Its easy ill show you how. Good ridence sir.

To the guy whom started this thread......sorry about the jacking man. if you wanna use that head itll be alot of fabrication. Not worth it like everybody else says just swap a ZC or b-series. good luck man
 
Don't let Blanco's arrogance get to you, he can be knowledgeable an helpful, but he seems to be constantly menstruating. Anyway, I agree with you, the customization involved is not worth it unless you already have the parts, access to a machine shop, and a lot of time on your hands.
 
I've seen it done. I gave some guy bolt a earlier integra DOHC head on my old d16a6 block that i gave him
I don't really talk to him anymore.

and i don't really know what parts he used. I would assume the head studs from a DOHC head and he used a d16a6 head gasket^_^

other than that I have no clue.
 
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