Help on prepping d16 for boost
 

I'm strengthening the bottom end of a d16 sohc vtec with Ls rods to withstand a good amount of boost. However i also was thinking of doing a port and polish on the head and 3 angle valve job and getting a turbo cam shaft. I'm not sure if i should go that route because of the compression ratio. I know i need to lower compression to be able to boost higher without blowing the motor. Should i just forget the port and polish and just get the cam or quite the opposite? Will it increase compression or lower it? Can someone help me out?

You don't need a lower compression ratio, but it usually helps. Basically, how much power you looking for? The D has a modest compression ration anyway (usually around 9.6:1).

Ls rods are a good start, so i'm assuming you're not looking for rediculous numbers, just more reliability. What do you plan on doing about pistons? Vitara possibly?

Changing up the valvetrain shouldn't affect compression unless you're changing out the valves that are different from stock spec, which may raise or lower your CR depending on the shape of them. I wouldn't focus on the valvetrain so much, depending on the D you're boosting. Are you working with a z6 or Y8 or other?

Oh and this should be in the turbo forum, under the high performance category :yes:

I'm boosting a d16z6. I had thought about pistons but could use some more info. I'm looking to boost atleast 10psi to start and maybe some nos later.

So you really think i should just focus on the block and not the head? Does the turbo cam even make a difference?

Generally, stock heads are fine, including the cam. Since youre already forcing air through the head, porting doesnt become necessary until youre into the upper 300whp range.
The weak link is going to be blowing out the bottom end before anything. Rods and pistons should be your focus of a minor build (but you probably dont need that).

What kind of turbo are you planning on using? 15g-19t size? What fuel management?

Honestly, you need to pick a power goal, rather than psi. From there you can pick what parts you need, based on a little research. Its not boost that kills engines, its power.

i'm trying to go atleast 200 to 250 horse running a 15g and greddy e manage with a full fuel system and ignition with a few basic bolt ons. Let me know if you think something would be better than what i'm thinking. i feel you on the head thing so i'll work on the block instead. Any other suggestions?

I agree with Pat (Pdiggity) to some extent, but I think head work is an important part of any turbo build up. The lower end is definitely a priority, but a valve job and/or port and polish will only help along matters. A 3 angle valve job is pretty amatuer these days...something like a 5 angle or radius valve job would work better. As for cams, none should raise or lower your compression ratio dramatically and many turbo specific grinds can really do wonders for your turbo's response time. I know Comp Cams has a good online tech dept. for cam selection if you give them your specs. It's my experience that a good head/cam selection can mean a world of difference in a turbo build. It might be a little less critical in a Honda build up, but mine was night and day.

good choice with the z6, i hear they have better oil pumps and better bottom end oiling capabilities than the other d motors. However i'd DEFINATELY suggest swapping your intake manifold for a d16y8 manifold. The plenum is bigger and will flow more.

Also the emanage is kind of shit unless you know someone who can tune it good for you. Otherwise i'd suggest something like hondata, uberdata, crome, turbo edit, etc.

If you want to focus on valvetrain, why not just replace the valves, retainers, and springs, and raise your redline. Have a real screamer.

That's great input guys. Replacing the valves and all that stuff was already on the list with the head build up. I just don't want to waste the money if it really won't make too much difference. We are on the same page with the intake manifold. I was already going to swap that too. Thanks for the comment about the e manage. I've done my research on the Hondata ecu's and they are definetely the best in my book. Problem is getting one at a cheaper price. Then again you get what you pay for right, so it's gotta be worth the money. Anything else you guys can think of let me know, i'll be taking out the motor hopefully within this week.

With a power goal fo 250whp, you will need a little bit of head work. I can tell you now that porting and polishing the head will be critical. ..... that is ofcourse after building the bottom end first.

So get your bottom end built first. Then look into a decent size turbo. I say a T3T04b 48/57 trim.

If you decide to P & P your head, enlarge both intake and exhaust ports but do not polish the intake port,. You want a rougher entrance to optimize your air/fuel atomization.

yeah hondata can be pretty pricey, which is why if you're decent with computers, and electronics, you should go with your own enigne management. A lot of people tune with uberdata, which is like a free version of hondata. You can download it free, and control 2 sets of fuel maps, ignition maps, and many other parameters. All you would need is a chipable OBD1 ecu, conversion harness (if your car isn't OBD 1) anda chip burner. Basically, hook it up to the comp, burn a chip, drop in the ecu, and go.

Ok guys, i think i got my setup mapped out. I guess we'll see how it goes. However i got one more question. Would you suggest the si vtec tranny for turbo or the Cx, or DX tranny for the longer gears? I think the DX but the Cx would be the same right?

Y8 tranny is the best D-series tranny Honda ever came up with.

Any particular reason why that tranny is better??

Steve

gearing is better. it has a more sporty ratio with shorth 1st and 2nd, then a strong 3rd and a medium range 4th, then followed by a long 5th...........

well i bought the ls rods and what kind or what size bearings do i need to put for the main bearings and the crank bearings

You know that the LS rods will have to be machined right? Get ACL bearings or OEM............

well yeah i know it will be machined but they will tell the size i will need right
also i just droped in a d16a1 in one of my friends del sol and we can get it to work right what wrong
the car cranks over it tried to start but nothing
i replaced the ignition module and the rotor cap and coil is there a certain way to wire the distributor cause the car is a obd1 and i went to a obd 0 distri
i followed all the wire colors and the sepearte crank angle sensor to the ecu
i take of the cap and crank the motor over its sparks once the a full turn goes then it sparks again
i dont know what i did wrong let me know

p.s beside that i put a d16a1 turst me the motor is worth it

http://www.hstuners.com/forums/showt...threadid=16805

Check this out bro.:bandit: