Alright, so I bought a D15B7 with a Y8 head on it for dirt cheap, and I was going to throw the head on my Y7 block, and completely rebuild everything. My question is... From my research, the D15B7 pistons will give me the highest compression ratio 11:3ish in a Y7/Y8 motor. Is this correct, or does somebody suggest better pistons? And what rods are suggested? Thanks!

 

Anyone have any thoughts on this....looking for some ideas as well to build up my D series and what to go with

 

if you run the d15b7 pistions in the y7 block your compression ratio is 12.70 here is a online compression Calculator that will help you out it is

http://www.zealautowerks.com/dseries.html

 

Bump, I'm down to see some serious all motor d series powaaaa

 

about the compression i have no idea.

what kind of goals do you have in mind? and what is the normal intended use for this build? is it a track car and if so what kind of track(road course, autox, strip)? DD with some more go? this will let us know what part of the powerband the focus needs to go to.

in all honesty single cams are pricey and require alot of research and time choosing parts that compliment each other in order to get any kind of serious power out of them. this is mostly because of the head flow..........they just arent designed to flow alot of air, and the head is where power is made...........it determines almost everything about the way and how much power an engine is capable of making.

 

wow i never saw d-series and pricey in the same sentence before whats pricey about a single cam

 

Well compression wise, from my calculations online and stuff, I was getting 11:3ish, as I stated, but basically, I'm planning on a Crower Stage 2 Cam, upgrade the valves and retainers, Integra throttle body, port matched stock Y8 intake manifold, 3 angle valve job, and throw some decent pistons in for DD use. Then save up for a turbo kit and vitara pistons with forged rods down the road, but for now, minor DD power....

 

cant run the b7 pistons in a 1.6 block without some serious modification to the quench pad.

 

sorry, let me clarify.

single cams are pricey if you want serious power AND want to stay N/A(kinda assumed this is what we were talking about since this is the all motor forum)..........on the opposite end, they are about the cheapest engines to boost reliably.

if you want lets say 200whp(approximately 220-230hp at the crank) then a B series is a much less costly choice as well as easier...........the biggest thing is that a Bvtec is alot closer to the goal than ANY d series.

 

ok good, got somewhere to go with it. minor DD power is what the D series does best NA.

what octane fuel do you want to use? if youd like to stick to 87 then i wouldnt recommend running any higher than about 10.5-11:1 compression. maybe not even that much. if it doesnt matter then about 12:1 is about as high as youd really want on a street car.

a good header, and exhaust, CAI(i would only use one that has a water drain built into it), along with your other plans and you should have a good strong motor. but you need to have it tuned(on a dyno is by far the best way) so you can take advantage of the bolt-ons. and youll definitely need to have it tuned when you boost it so you might as well go ahead and get a tuneable ecu now.

 

you have to count in the cost of a. buying a b swap which can range from 1500 to 4500 pending on which one yo get plus the money to build the b-series i still say its cheaper to build a sohc motor if thats what your starting out with

 

yes but you can pretty much get 200whp out of a gsr with bolt-ons, and you dont have to buy a b swap(although thats my preferred way to do it) you can easily and pretty cheaply piece together a good b series for less than a swap kit. getting a sohc NA(no nitrous is not NA, in case anyone was wondering) to 200 whp takes alot more work/time/money. id estimate that getting a sohc to 200whp would probably cost somewhere north of $5000(thats just the cost of the build, not including the cost of the engine but thats not much, id say 1000 on the very high end for a good used D).

BUT thats not what we are talking about, the OP is wanting a DD with more power.

 

even on a stock single cam,i would invest in a lower final drive,the stock 4.26....asuming its a ex/si still suck. i would go for a 4.4 for turbo or 4.7 or even 4.9 for n/a. imo,best bang for your buck, it think around 500$

 

wtf are you talking about. 180-200hp from a D is not hard or expensive if you know what your doing and its built/tuned right. A z6 head milled .04" a large cam from the likes of a crower 3, Bisi, delta ect, either ITBs or an Edelbrock intake and some good headwork with a nice header and your there. I dont see where you have to spend 5k to get 200hp. Thats just you not knowing what your talking about. It has been done before by people for relatively cheap. And i would LOVE to see a GSR with bolt ons hit 200hp. It MIGHT cost 3k to get the D to that level if you shop smart even less.


I'd honestly do a mild build with a stg2 cam about 11.5:1 compression some port work clean up and put my money in the trans. Thats the D downfall. Upgrade the FD and get an LSD. Money is much better spent there for bang for the buck performance feel.

 

dammit 4g beat me to it. stupid typing at work

 

So let's say you spend $1000 on valvetrain, crower cam, head work, bottom end pieces (new pumps, bearings, etc...), machine work, blah blah...then he has to spend $$$ on a tuning capability and the actual tune itself, plus he's compromised the oem reliability a stock motor has from the factory. In the end he'll put down 150whp and he's still stuck with the shitty gears an ex/si trans comes, not to mention those transmission are weak as all hell, and he needs a good clutch/flywheel...That's just my opinion....He says it's a DD so ridiculous compression and cams are out of the question.

Or you get a b16 swap that puts down 140-150whp in stock form for $1500. The b16 uses stock mounts, stock ecu and has a stronger transmission with better gearing. All it requires IF you want to go that far is a new oil pump/tbelt/water pump, clutch and flywheel before you put it in to guarantee reliability for a few years.

 

to the OP, normally if you were just wanting more power and had a good longblock id say leave the bottom end alone, but since you are piecing together some suff then yeah go ahead and use some higher compression pistons, hone it, make sure all the bearings and journals are good and start with a fresh bottom end. a lil head work and a cam and some bolt-ons........youll be good to go. id say get a set of cheapo pistons to run til you boost, and upgrade then.

 

well for one if its a crx or ef then yes it will cost about 1700 for a b16 swap which only puts down about 139whp but if its in a eg chassis he is gonna spend 2500 for that b16 swap and get 150 whp out of it

 

d16 with bolt ones will beat a b16 for the same price

 

200whp NA D for 3k? id LOVE to see that. lets say you run it to 8500rpm, 200hp means that the engine is also making 123ft/lbs.........at 8500rpm. and by that rpm, pretty much any engines torque has already dropped off, so that lil D series would have to have peak torque HIGHER than 123ft/lbs, my guess would be somewhere around 135-140ft/lbs. its going to be really hard to move torque up that much, and that much higher in the rpm range.

if you didnt rev it any higher it would be worse, 200hp@7000rpm means 150ft/lbs.........thats almost 50% increase in torque.......and about 75% increase in power............no way you can get that with 3k on a NA D. and yet again that 150ft/lbs has already dropped off so peak would have to be around 160ish ft/lbs?

and all of those figures are at the wheels.......so really you are talking about 220hp and 136ft/lbs @8500.........or 220hp and 165ft/lbs@7000. 165ftlbs @7000? out of a NA D? possible, yes....for 3k.......absolutely not.

and btw my definition of bolt-ons is a lil different than most. i consider cams a bolt-on........on a OHC engine, its just too easy.

 

its all good but thats what alot of people dont understand. lower fd multiplies torque!!!! the single cams are great motors,they just need a little tweaking to get them right. put your $ in the tranny and you will be more than happy. i would rather do a bolton single slam and have my tranny right then all the money in the motor with a sucky 4.26 fd.

i know this is the all motor forum but since you may go turbo down the road,there is a guy that lives up the road from me with a stock z6 with a greddy kit on 10pounds i think. should be close to 200hp,and bolton mustangs,camaro's,with gears,etc.... all get there feelings hurt by many car lengths,lol!!!!

 

D16 has a stroke of 90mm. its not hard to make torque on them. Like i said spend about 1500 on the motor and 1500 on the trans and it WILL have no problem whooping up on a GSR that cost the same just to swap in. People out there have done it numerous times, you just need to know where to find them.

 

Ahhhh. FINALLY!!! Someone testified it RIGHT!! I'm using this quote onto the Honda D guys in the local forums

 

Not to sound harsh, but I GOTTA hear the explaination to THIS particular form of logic

 

this is taken directly from mfatorys website,i hope they dont mind!
By changing your final gear ratios, you can experience a dramatic increase in acceleration, giving you on average, a 10-15% increase in torque throughout the entire rev-range over the OEM Final Drive.