quick Q about SOHC ZC into 90 si crx

[Mad Mike]

I've been told that since I have a SI with the SI wiring harness All I need is a conversin harness and a P28 ECU(i think or was it a P30 ECU) to drop the SOHC ZC in my crx. My motor is about shot and I would like to upgrade but I want to stay on the low side on the cost. Thats why I want to keep it SOHC and then later down the road maybe Boost.

any help would be great I need as much info as I can get so I know what i'm getting into.

thanks

[bigdare23]

huh?!?

a sohc zc is non vtec, so you remove your old motor and install the new one and reuse all of the the d16a6 stuff.

unless your talking about the vtec d15b.
then I would convert my car to obd1 and use a stock p28

[Mad Mike]

o ok i thought the sohc zc was vtec.
does the d15b have more power than the d16a6?

[bigdare23]

o ok i thought the sohc zc was vtec.
does the d15b have more power than the d16a6?

yeah it "suppose" to have 130hp to the crank

[Mad Mike]

so to drop in a d15b vtec motor I just need the obd0 to obd1 conversion harness and use the P28 ecu?

thanks for the help

[Goinfasterthanu]

Mike do the d15b... Its the best stock D IMO... My friend Doug has one in his si crx and ran a 14.8 ... We have the zc{ non vtec} in our crx and its slow as balls compared to dougs.... Just a little food for thought... I also am VERY good friends with the owner at pacific motor company.....lmk if you need any help

[Goinfasterthanu]

so to drop in a d15b vtec motor I just need the obd0 to obd1 conversion harness and use the P28 ecu?

thanks for the help

Correct

[Mad Mike]

Mike do the d15b... Its the best stock D IMO... My friend Doug has one in his si crx and ran a 14.8 ... We have the zc{ non vtec} in our crx and its slow as balls compared to dougs.... Just a little food for thought... I also am VERY good friends with the owner at pacific motor company.....lmk if you need any help

thanks I'll let you know but it will be around tax time befor I can swap it. O and I think I know witch crx your talking about was it the one at comerce when I was there for the first time in my crx?

[bigdare23]

Mike do the d15b... Its the best stock D IMO... My friend Doug has one in his si crx and ran a 14.8 ... We have the zc{ non vtec} in our crx and its slow as balls compared to dougs.... Just a little food for thought... I also am VERY good friends with the owner at pacific motor company.....lmk if you need any help

LOL zc are slow as hell, I used to whoop up on my homie how had a gutted rex with a zc. All I had was an a6.

[Mad Mike]

ok another Q

Would it be easier to do a d16y8 head swap onto my d16a6 with a rpm switch for the vtec or just put the d15b in my car with the harrness and the P28.

I mean in cost and time down. As far as I can tell the only thing wrong with my a6 is the valve stem seals are leaking.

heres what I've been studying
http://crx.honda-perf.org/articles/m...oreminime.html
and
http://crx.honda-perf.org/articles/z6swap/z6swap.html

thanks for the help

[Goinfasterthanu]

dont waste your time...All in all after its all done you come out about the same. IMO if done right... Then you still wont have a nice 40k motor... Make your rex run 14.8's for 5xx$ and VERY little hassle ... Its a easy choice..

[Goinfasterthanu]

Oh and for that little build your talking about will NEED tuning to get it to run right and get good power out of it....{ assuming your doing a mini me }

[Mad Mike]

dont waste your time...All in all after its all done you come out about the same. IMO if done right... Then you still wont have a nice 40k motor... Make your rex run 14.8's for 5xx$ and VERY little hassle ... Its a easy choice..

so your saying go with what motor d15d, y8 head or z6 head on a6 block?

[JDMef88]

ill vouch for dougs car- its pretty nice the d15b pulls pretty nice in his rex way better then an sohc zc- thats just my 2 cents

[Mad Mike]

ill vouch for dougs car- its pretty nice the d15b pulls pretty nice in his rex way better then an sohc zc- thats just my 2 cents

yea the sohc zc is out of the q now. i think i'll be going with the d15b setup.

[JDMef88]

dude i was gonna throw a d15b in the rex i bought from bucky awhile back..but had to sell for money issues....the d15b in the rex is worth if ur going budget and a fun little sohc...let us know how it works out and best to luck with ur project!

[Mad Mike]

o yea on the d15b motor will my si crx tran bolt up to it? is the flywheel and clutch the same? I just want to get this all strait so when I start buying things I get the right stuff.

[THEONE]

huh?!?

a sohc zc is non vtec, so you remove your old motor and install the new one and reuse all of the the d16a6 stuff.

unless your talking about the vtec d15b.
then I would convert my car to obd1 and use a stock p28

actually there is a jdm sohc zc that is vtec a freind of mine had one and yes it says zc on the block and it has about the same power as a dohc zc.

http://www.jdmenginescorp.com/index....roducts_id=120

[KidSaru]

o yea on the d15b motor will my si crx tran bolt up to it? is the flywheel and clutch the same? I just want to get this all strait so when I start buying things I get the right stuff.

Yes.

actually there is a jdm sohc zc that is vtec a freind of mine had one and yes it says zc on the block and it has about the same power as a dohc zc.

http://www.jdmenginescorp.com/index.php?main_page=product_info&cPath=1_2&product s_id=120

Same thing as a D16Z6.

[Mad Mike]

ok thanks

[Goinfasterthanu]

See d15b is a sick ass motor for stock 1.5....

[Mad Mike]

yep thats the one I'm going with. After I get my taxes back I'm ordering all the stuff to do the swap. i cant wait to hear the vtec crossover

[sakasaku]

find a cheap dohc b18

[Mad Mike]

no sohc is the only way.

[THEONE]

no sohc is the only way.

explain why sohc is the only way????
why? i roll on a budget so for me the dohc zc was the one. a compression test and a minor engine run through and a little boost i was at 208whp @7psi in my old ef hatch(plenty of power for a street car). that was turbo kit,clutch kit and trans and tuning at mainstream.i was at 1500.00 for all. it took about a month to pull it off. dohc's FTW sohc's are nice but like i said dohc...FTW to me you get more flow in the head from a dohc more than a vtec head,when you balance cost to power the dohc zc comes out on top. i think you will make more power with the dohc zc than a sohc 1.5l vtec motor. **** vtec..if your on a budget and your in to real power and on a budget the dohc is the way.you cannot change my mind on this and if i did another honda build i would do a dohc zc power plant simply because i have used it a few times and i know its potential and weaknesses. but as for now im a german performance guy ahh yeah thats right bmw FTW

[Mad Mike]

explain why sohc is the only way????
why? i roll on a budget so for me the dohc zc was the one. a compression test and a minor engine run through and a little boost i was at 208whp @7psi in my old ef hatch(plenty of power for a street car). that was turbo kit,clutch kit and trans and tuning at mainstream.i was at 1500.00 for all. it took about a month to pull it off. dohc's FTW sohc's are nice but like i said dohc...FTW to me you get more flow in the head from a dohc more than a vtec head,when you balance cost to power the dohc zc comes out on top. i think you will make more power with the dohc zc than a sohc 1.5l vtec motor. **** vtec..if your on a budget and your in to real power and on a budget the dohc is the way.you cannot change my mind on this and if i did another honda build i would do a dohc zc power plant simply because i have used it a few times and i know its potential and weaknesses. but as for now im a german performance guy ahh yeah thats right bmw FTW

I hear ya. Will the dohc zc drop in? Is it just like the sohc where all i need is the conversion harness and ECU?

[THEONE]

yeah the zc drops right in and since you have a si you need no harness. its just re pinning the harness on the distributor. you can even use you si ecu it works great.
http://www.phatwhippincrx.20m.com/photo6.html

[silverEJ8]

The jdm d15 vtec is a strong motor, but its not any better than a D16z6. The HP numbers are the same but d15 vtec has a slightly more aggressive cam than the Z6 but the Z6 has a greater abundance of parts for high compression and cams.

In an EF i would do an A6 non vtec with Y8 head. (I believe the non vtec zc is the same as the A6.) The compression ratio will be 10.3:1 and the A6 distributer bolts/plugs right up with no modifications. Run a couple wires for VTEC to the ECU and you are done. If you are worried about an ECU get a JDM b16 PW0 or PR3 ecu and stay OBD-0. You could convert the car to OBD-1 but then you would have to buy the converssion harness ($100) plus a p28 ecu ($75-$100) verses a JDM b16 PW0 or PR3 ecu for $100.

I have an A6/Y8 in my 91 si and it is a Great build. I/H/E on the A6/Y8, with a light (30 minute) tune and you are running with B16's in EGs. And once again parts and modifications are so easy to find and are cheap. (A lot cheaper and easier to find than aftermarket parts for a Dohc ZC)


A Lightly Built D16 Will Rock A B16"s World For Half The Price!

[Mad Mike]

thanks for all the help.

going to go pick up a z6 motor today. Ecu is on the way and I found a used convesion haness for cheap.

[bigdare23]

thanks for all the help.

going to go pick up a z6 motor today. Ecu is on the way and I found a used convesion haness for cheap.

Just don't expect killer gains over the d16a6, but I think you will still like it!

[Mad Mike]

Just don't expect killer gains over the d16a6, but I think you will still like it!

yea not expecting a lot from it. but after some resurch i've think it will be a easy and cost effect upgrade. Plus the vtec head will like the boost it will get soon.

[bigdare23]

yea not expecting a lot from it. but after some resurch i've think it will be a easy and cost effect upgrade. Plus the vtec head will like the boost it will get soon.

I'm glad you did the research before hand (most people dont). I believe you would be happy with the results after boost! Reps!!!

[TheProfiteer]

yeah it "suppose" to have 130hp to the crank

I thought it was 118 to the fly

[Goinfasterthanu]

I tried....

[Mad Mike]

Z6 is in my trunk in my garage.

Small problem thoe I cant get it out. to heavy to lift it out by hand with three people. Well I guess it gets to hang out untill I go buy a engine hoist.

[Goinfasterthanu]

humm...who do you know who has one...... i wonder...

[Mad Mike]

lol to bad I cant barrow that from you.... no I'm going to buy one this week because I have some more plans and motor swaps down the road.

[Mad Mike]

I do have a Q about something, the distributor. The plug is different from the harness plug. Hows this going to work? Do I need to get a conversion harness (saw something, someware about this) or what? thanks

that and I still havent examend all the plugs on the motor compared to the harness. Is there any other ones that are different and also I have the motor harness for the z6

[Goinfasterthanu]

Yea youll need a conversion harness... 2 if i remember...

[SLPR]

this thread was helpful to me...reps for mad mike.

but u can probably goto RYWIRE.com and buy the harness.

EDIT: well i tried to rep