I am new to this site so sorry if i make some mistakes. So i just bought a 1990 Si Ef and it has a mini me swap in it. It is the D15b7 block and a Y8 head. It has the si tranny and feels pretty quick to me but i keep losing to my friends Dohc cars like Tc's and Tegs and celicas. I do not have V-tech hooked up yet do think when i hook it up i will make more Hp or am i maxed out. I also have Cold air intake and a Aem cam gear, no exhaust yet. I wanna stay D series becuase nobody has it and i like them. What can i do to make it faster. I want to turbo/Nos but idont know how much boost this swap can hold because i didnt do the head hasket. What do you guys think i should do? Just go b series or boost this? Thanks for the help.

 

How much money do you have to play with?

Do it right. Build up a zc block with the vitara pistons and scat rods, good headgasket and head studs. Then bolt on a turbo/intercooler kit and get your ecu chipped. Learn to tune your ecu and you'll be happy.

 

I'm a student in school and this is my project car so funds are a little short. Thats why i wanted to know what to do with my current set up. And i can get D series parts for cheap. Thanks

 

if you dont have much money to spend then sticking with the d-series may be the best bet. either that or save up for awhile and drop a b-series in it. it will be a bit quicker if you get the right ecu in there and hook up vtec, but you still probably wont be as quick as your friends with the dohc engines.

 

drop some p29 pistons in get the compression up a lil and start from there. it all depends if u are tryn to go all motor or turbo

 

Yea i have a P28 waiting to be installed just need to find a jumper harness for cheap. I want to go turbo but my car sits outside, so i kinda want to stay hidden from the thives and to go all moter?? but idk i was thinking of just pulling my head and getting it port and polshied and three angle valve job, throwing a cam in it and getting it tuned with all mods. Think thats worth a try? and last night i seen this old theard and had a few questions. It says you can put 1st gen supra 75mm pistons in a D16 block with b16a rods and boost 20 Pounds easy. Any one ever tried this and had a success? It is a few years old so i want to know how long the moter can do this before blowing? Thanks againand had a success? It is a few years old so i want to know how long the moter can do this before blowing? Thanks again

 

Toyota/B16A hybrid piston/rod package for SOHC D-series engines

https://honda-tech.com/forums/forced-induction-16/anyone-still-interested-toyota-b16a-hybrid-piston-rod-package-sohc-d-series-engines-267641/. Sorry forgot to put link in.

 

I think for you a good investment would be a stage 1 cam, but DEFFINATELY get the p28 going and hook up the vtec

 

The Toyota/B16A hybrid route was 6 years ago. Since then people have been using the Vitara pistons with same/better results. (keep in mind these are NOT OEM factory Vitara pistons - doing some research will show you the brand to get which has a special coating on them.)

Looking at how you trying to judge how quick your car is and you don't even have vtec working isn't really fair to your car right now.
I feel sad for your EF =(
Is there an address that I can mail it some flowers?

I see your budget is way tight too.
Seems like you are having difficulty pulling together about $100 for a jumper harness?!?!?
Totally OK - not all people were born with a silver spoon in their mouth.
You are in college so you will do well some day I'm sure!

If money is a major concern then seriously consider NOT messing with your car.
Get vtec working and hold on to your cash until you are really ready to dive into the money pit of performance mods.

If you have some money to burn then first thing to do is get a HELMS or Honda service manual. Don't mess with Haynes and Chilton crap
I suggest you find a spare motor to tear down.
Don't mess with your daily driver engine if you want to have any use of your car while you are building your power plant!
Look for a Z6 short block (should be easy to find and cheap!). It's a great platform to build from.
On the CHEAP you need to invest about $500 at least just getting the block to do magic.
It's a 15 year old engine so if you just throw it in with no work you can expect it to give problems.
Tear down the block and take the crank, flywheel, flywheel bolts, and case into a decent engine machine shop. Have them micropolish the crank and balance your rotating assembly (good shops will bolt the flywheel to the crank and balance)

Have them measure and inspect your cylinder walls - from there you can decide what size piston you will need. If you need a bore then you will need to order oversized pistons.
Go for boost! D-series all motor normally aspirated setups are DEPRESSING to say the least... unless you have $$$$... and at that point why wouldn't you spend it towards a FASTER boosted setup?

Ahhh - get the Vitara's!
You need a decent aftermarket rod too - check out other peoples Vitara builds for what worksl.
Back to the machine shop to have the pistons installed on the rod and get them balanced and blueprinted as well.

You can assemble this yourself if you have the tools (highly recommend this - take your time, use the right tools, get the RIGHT help, and learn a boat load of info!) or pay a decent shop to put it all together for you. I assembled my first motor in about a week. Only worked on it about 1~2 hours a day and triple checked everything I was doing. Loved every minute of it!

Now you have a killer D-series platform to build a rediculous turbo setup to destroy everything. A stock Y8 will do just fine... or build one up if you are going for the gold.
Again, not cheap. It takes money to go fast.
Hope you got $ to invest.
You can get the cheap eBay garbage, but it's priced like that for a reason.
Research what other people are using!
No reason you shouldn't be able to hit 300~400hp on this block with proper equipment.

Tune tune tune tune tune.
Oh, did I mention TUNE?

I know I left stuff out here and there... you can find EVERYTHING you need with some light searching.
The forced induction section her on H-T has some goo Vitara builds as well as some budget ones.
Take a look!

 

I say differently on the comment on all motor single cams, there's a rex NO BOOST on you tube running 11's with VERY minor mods. So it is possible

 

Outstanding post sir

 

Prove it.

Unless it was an HF, those things are light as hell

 

A general rule for determining which size shot to use on a stock engine is 40%-50% of the engine's factory horsepower rating.


A stock HF weighs in at 1713lbs... the lightest of all CRXs.
Wiki says they weigh more http://en.wikipedia.org/wiki/Honda_CR-X 1819 and 1834, but I'm being subjective and going with these lower weights found on http://www.crxsi.com/specs.htm

With no driver, wind resistance, etc.
You break into the 11's at (11.99) with 196hp.
You would need 230hp at the flywheel to achieve this.
I think adding a 168 shot of nitrous is a lot to ask from this incredibly weak 62hp engine.

So lets try the DX model.
Again, the unmanned 1819lbs car flies down the track in a wind tunnel.
This time it needs a 150shot to get it's 92hp motor to pull off an 11.99

So maybe the Si
2017 needs 271 hp.
105 shot of nitrous.


Ok... MAYBE it could be done on that 105 shot, but not many times.
If you put a 160lb driver in you need 20 more hp in there.
So figure this guy pulled it off with a 125 shot.
We didn't even talk about D-series RODS. Typical failures happen around 240hp.
Safe hp on a stock rod is 220 and LOWER.
This guy pulled it off without bending a rod at close to 300hp!

Remember this? A general rule for determining which size shot to use is 40%-50% of the engine's factory horsepower rating.
Dude is needing just about 100% more the engine rating. Reliability went out the door.
If he pulled it off and ran his 11.99 down the quarter mile then he did it a few times, but then what happened to his motor?

I've heard of people doing a 300 shot on a relatively stock block and race gas.
Fun for a little bit then pure carnage as the internals of the engine fried and parts flew out all over the place.

Typical NOS recommendation on ANY stock block is 50shot. 75shot if you have a newer engine or a low mileage rebuild AND you don't use the NOS often.

 

quick mod throttle body change what tb u got on there and try a d16a6 cam theyre ment for abuse tb apparently i heard all d h f b tb's are interchangeable and try some headers catback exhaust i dunno im just throwing in cheap bolt on mods school understand also you might want to get a short shifter im pretty sure your shifting is a lil sloppy compared to your buddies b car so lessening your throw will help you get through your gears more smoothly and dont forget number one hp helper.................stickers jk also fuel management system could benefit

 

...hmm
this thread is very interesting..
if your as broke as i am going to college...
stay d.
buy a helms manuel..
figure out why your vtec isnt working..who told you vtec wasnt working?
what ecu are you running? is this why vtec isnt working?
is the car obd0 or 1?
lots of stuff we need to know to help you correctly
whats your budget? get very serious here or youll be spendin out the a$$
make a plan and stick with it..dont build an all motor car and half way through it go turbo..
and be serious with your self. if you have another daily driver then ya tear that ***** down and build it up...
if not start small
now to answer your question..
once you get vtec working properly you should feel a good differnce not break your neck or anything but def better..
you have an intake.
you said you have the y8 head if you have the y8 intake manifold that is better than than a b7 or z6 so you should be good there
you have the si tranny..good
what size are your tires? if your rollin 17s then that will slo you down..
also if you have rubber band tires you will ..WILL MOST DEF..spin alot more of the line
if you get an exhaust get one all the way back with hi flo cat..please dont just get a fart can..
if you plan on builing the motor..
first all motor or boost?
boost will yield more power for about the same amount of money
you can use around 8 psi with decent tune on the street and if you go to a track every now and then turn it up to say twelve with a good tune...
like the guy above mentioned....tune tune tune
if you want to just budget build an all motor
dont get a cam without higher comp pistons..you wont feel as big of a diff.
def head bolts and probably newer and better valvtrain
again tune tune tune
wow so just realized how much i wrote..so ya
i hope i helped



edit also that 8 and 12 psi is for a stock motor
you could do way more with a fully built motor

 

sorry, but 'psi' really isn't a term used for power.
It tells you nothing other than pressure created.
A larger turbo blowing 5psi will produce more power than a small turbo pushing 5psi.
Putting 12psi from a larger turbo will likely blow up a stock motor.
A small T25 or TD04 at 12 psi would probably be ok.

You need to look at compressor maps of the turbo you are looking to in order to figure out what power you should expect.

 

very very true
i was in a hurry posting that.
i also didnt think he would jump right out and buy a 90mm turbo
but none the less not informed is better than misinformed
thanks for clearing that up!

i personally love smaller turbos because i HATE turbo lag..
im more of an all motor kinda guy i guess thats why i hate lag
to bad its so exspensive to do that with a four cylinder

 

Ok thanks for all the feed back guys. Heres my whole car. Y8 intake manifold with Y8 head with d15b7 its a obd0 car running a Pg7, i need the jumper then i can wire V-tec. I have some aftermarket 14's 165/55/14 Toyo tires. And i have about 1000$ to spend on build. I am going to build it over this upcomeing winter. I dont have the money now but will get it over next few months. Got something bad to tell you guys. the wiring is all messed up from the previous owner that swaped it, the wiring is all cut and taped back together for Y8 head. i need a new harness but then 2day i was driving and down shifted to thrid to pass a car and my passneger side moter mount broke and the moter fell and broke my Cv shaft. I dont know how to post pics but im taking some 2maro to show you guys. oh yea and before this it would bog sometimes at 1200 rpm then i would restart car and it would go away. Thanks for all the help

 

wow...
how in the hell did the mount brake?
were they aftermarket or what happend?
and if i were you i would go and find all new wiring
get the cars origanal wiring and cionvert to obd1
im not sure what the pg7 came out of...
and i guess i dont understand what kind of bog you were talking about

 

Yea it was wierd wait till you see the pics.lol they were factory. Oh yea this isnt a daily driver its my second car. Yea what harness should i use i cant find any si ones and will the Si one work with my mini me or will i have to cut it up again. it would just die at throttle above 1200 idk this car is haunted i think. lol Can i use a Jdm b16 obd0 harness?

 

have to use the stock harness. so an si harness from 90-91

 

Ok thanks. But what will i have to do to make stock harness work with Y8 if anything?

 

ALL MOTOR SOHC MONSTERS

http://www.youtube.com/watch?v=BGD9RcVDWGY

 

yea your gonna have to do some wiring but just for vtec i think..idk if theres a knock sensor you have to worry about or not..i want pics!
i would also tell you to go ahead and go obd1 for tuning purposes
this means you would need a need
new dizzy (i would get a new cap n rotor if it was used)
your p28
and o2 sensor
also unless you wanna spend alot of time researching go to rywire and get the conversion harness..
i would also invest in some aftermarket mounts

 

Become a better driver. i have a dx civic with basic mods cai, headers, exhaust. I have some what stripped interior still have the back seats and 0 to 40mph I have beat b16's b18's but I do lose to a lot more cars like WRX's and other more powerful cars. I had a turboed integra before my civic and it beat a 500hp Mustang because he was spinning tires. Use the civics lightweight and good trans gearing (1st goes to 30mph and 2nd goes to 60mph) That is one less shift u need to make to get a good jump on the competition. 0-40mph after 40mph they will fly by u