d16y8 turbo build...???

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CRXSi86

Fatty
Alright, here's my problem. I have a 96 Civic DX with the y7 in it. I wanna get a y8 and completely rebuild it, all the good stuff, and also setting up a turbo on it with a dsm t25, 550cc injectors 255 fp. I have all that down.

What my question is and I have searched multiple forums for this answer but..... Im having trouble figuring out wiring/ecu etc... The y8 is an obd2 motor. and from what I understand to tune it pro[perly I will need a p28 ecu from an eg civic. Now that being said, I will need an obd2 to obd1 harness. In the state I live in we require an e-check to check for codes, etc. Will doin this obd2-obd1 force a code that i wont be able to get rid of?

and I also just want confirmation that I am able to use my factory engine harness with the y7 for the y8? or will I need to get the harness from a y8?

Thanks for any input...
 
If you have strict emission laws, chances are you're not allowed to downgrade from OBD2 to OBD1. Check with your DMV or some state traffic authority. It will not throw a code, but they will easily be able to tell if you're OBD1 when you should be OBD2.
If you are allowed to swap, all you need is an OBD2-OBD1 conversion harness from Xenocron. Click this link or the banner at the top, so B gets his dues:
Xenocron Tuning: Fuel Management and DIY Tuning Resource Center for Honda and Acura Performance - Hondata, eCtune, Neptune, Crome, TurboEdit, Uberdata
You'll need to add a few wires to the engine harness for the VTEC solenoid, but that should be it. The conversion harness might include these, ask them about it when you buy it.
 
Alright so here is the update. I contacted the local epa and found out that there is no way for them to be able to communicate with the obd system if I convert it to obd1 and by federal law if the year is 96 and its under obd2 then it needs to be tested as an obd2 vehicle...

That being said, Im gonna stick with my original plan and go with the D16z6 and rebuild that and shove it in a 92-95 coupe or hatch... if im ever lucky enough to find one, which seems impossible these days, haha...

Ill keep you guys updated on the build if anyone is interested.
Im getting the DSM T25 turbo, Greddy BOV, FMIC and return and feed lines sent this weekend. and HOPEFULLY I can get my hands on a Z6 at the junk yard this weekend as well. If I can then the tear down and rebuild begins...

and dont worry, I will take PLENTY of pics for everyone :D
Thanks again for the help, and let me know if you have any parts available, such as injectors, fuel pump, pistons and rods and such... thanks :D
 
You can turbo the 96, just find an OBD2 tuning option.
 
Yeh that makes sense. I think I might just do that...Im gonna continue on my search tonight on plenty of info for this build. Get myself prepped and ready for it. haha..

Either way I go Ill continue this thread (or should I start a new one?) on the build process and such...

btw what kind of tuning software is there for obd2, I have heard of crome, uberdata, and chip burning and stuff. I have also heard of hondata obviously but arent those only really available for obd1 ecu's?

Also, with the y7 or y8 motor, the cr is a little bit higher than the z6, im doin pistons and rods either way, but just out of curiosity, is it nessecary to swap that out running 9.5:1 cr? or would you just need to really get a good tune and lighten up on the boost?

AND(sorry) I have heard stuff about a feed line oil restricter... ??? I have heard some people say you need one, some people say you dont, but either way i know without one you could blow your oil seal on the snail, which is what I dont want... Its a dsm T25, not sure if the trims are different for these turbos or if they are all the same, but what do I need to do about that?

Sorry, I have done swaps before, but im a complete noob with the boost stuff, haha, I get how it all works and what i need to peice it together, just still learning so bare with me please :D just wanna make sure i do it right the first time. Thanks again. Its really appreciated.
 
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btw what kind of tuning software is there for obd2, I have heard of crome, uberdata, and chip burning and stuff. I have also heard of hondata obviously but arent those only really available for obd1 ecu's?
OBD2 tuning is less common and more expensive, but it's out there, and there are probably hundreds of options. Research as many as you can and find the one that best fits your needs/budget
Also, with the y7 or y8 motor, the cr is a little bit higher than the z6, im doin pistons and rods either way, but just out of curiosity, is it nessecary to swap that out running 9.5:1 cr? or would you just need to really get a good tune and lighten up on the boost?
Usually the latter. Think about boost as a variable dynamic compression. If you have higher compression to start with, you'll need less boost to make your power goal. Tuning high compression runs a higher risk of detonation, so obviously premium fuel is a necessity and a meth injection kit might not be a bad idea.
AND(sorry) I have heard stuff about a feed line oil restricter... ??? I have heard some people say you need one, some people say you dont, but either way i know without one you could blow your oil seal on the snail, which is what I dont want... Its a dsm T25, not sure if the trims are different for these turbos or if they are all the same, but what do I need to do about that?
It depends on your oil feed setup. Some are large enough to allow the full engine pressure to reach the oil seals which can cause damage especially old or chinese seals. Some feed setups run through a small enough diameter to act as a restrictor. The best way is to research how much pressure the turbo was designed to receive, then build the oil feed to provide a similar pressure. If the feed line you bought allows too much pressure, add a restrictor.
Sorry, I have done swaps before, but im a complete noob with the boost stuff, haha, I get how it all works and what i need to peice it together, just still learning so bare with me please :D just wanna make sure i do it right the first time. Thanks again. Its really appreciated.

That's what this site is for.
 
That's what this site is for.[/quote]

HAHA, great post man, Your really helping me out big time. I just did a bunch of research on the whole obd2 tuning thing and its WAY over my budget of what im gonna spend. I was also reading on just about every forum that when it comes down to inspection time they just swap over there injectors, map sensor, and ecu and such for the inspection the swap it back over after... I may stick with the y7 or y8 motor and just do that, cause it just seems way too expensive to do an obd2 tune.

Or if I find a good motor, I will stick with the z6. I found a y7 and a y8 on here in the classifieds so I guess it the better deal on that one and obviously if its close and able to be picked up, but Thanks for the help. Ill post new quetions if any come up... if not... enjoy the build thread which will be starting hopefully this weekend :D
 
i did exactly what ur talkin bout ... the only thing is when ur runnin the p28 u need a tune cuz u'll be off timing 7 degrees but i havent had any codes
 
Alright I know Im changin my mind a lot, but still kinda learning. Heres the set in stone what gonna happen. Im gonna buy all new internals for the y7 thats currently in my car right now. rods pistons, head studs, etc. just gonna work with that motor. go with the P06 ecu I believe, nonvtec and get that tuned with chip burning. and then. at inspection time, all I have to do is swap out ecu and injectors and sensors and I should be all set right?\

another thing, I am obviously investing in new injectors and fuel pump, is it nessecary to upgrade my rail? I have heard the honda stock rail can handle a whole lot more than what most would think its capable of... but just wanna get a set in stone answer, if there is one...
 
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update, done more research and have found nothing of anyone saying they need to replace the fuel rail so i guess that kinda answers my quiestion :D

God I love when a new project comes along. I have been up til like 2 in the moring for the past couple night just doing nothing but complete research on this... just wanna do ti clean and right the first time around. I kinda helped my buddy when he was doin his ls turbo build, he spent A LOT though on that, made 254 whp and 249 ft/lb. pretty solid numbers for a stock LS. but im pretty confident I should have everything under control with this build. Thanks for everything. and once again, Ill keep you updated on the build, Im gettin the turbo, fmic, oil lines and greddy bov shipped out tomorrow :D
 
UPDATE:

Just sent payment for DSM T25 45 trim turbo, Tubular mani, Greddy RS(I think) BOV and oil lines.... should be shipping out today is what he said....

also found good price on new Vitera low comp pistons(100 new)
tryin to get in touch with the seller, no luck so far...
Ill get pics once the parts come in :D
 
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