Let's put the D15 rod issue to rest
 

I've heard plenty of people say "D15 has pencil dick rods" regarding ANY D15.

I've also heard this statement doesn't refer to all D15s, just some. Some say the JDM d15b is an exception as it has the same rods as a Z6.

My main questions:

1. Does the JDM d15b vtec have the same size rods as a d16z6? Or pencil-dick?
2. If the answer to the above question is "they're the same," does that mean mean you can use D16 forged rods in a d15b vtec? Or do you still have to use the ultra-expensive d15 ones?

I just really want the answer to #1, #2 I'm just curious about.

Re: Let's put the D15 rod issue to rest
 

jdm vtec d15b rods are z6 rods. No you can not run z6 pistons in a jdm d15b block. The height issue comes into play. I have pics of a z6 rod piston combo vs jdm rod/piston combo. Actually have them in my garage side by side

And no you cant run aftermarket rods in a jdm d15b block

Its a bastard motor with no real support.

Re: Let's put the D15 rod issue to rest
 

you kinda contradicted yourself there...you said they are the same but that the d15b has no aftermarket rods, if they were the same you could use the z6 ones. Im assuming you meant that they are of the same strength but not the same dimensions

Re: Let's put the D15 rod issue to rest
 

Basically I'm just gonna buy the motor and boost it stock, so it should be a bit beefier than my old d15b7 then.

Re: Let's put the D15 rod issue to rest
 

You can run aftermarket rods in a D15B, finding aftermarket pistons is the hard part.

You need a 27.7mm pin compression height.

PM7's in a D15 block with 137mm rods = .052" above the deck...........

http://bonespec.com/Honda/D15Baby8/P...5/PA150013.JPG

Yes they WILL fit a nonVTEC head opening the chamber edges slightly, yet to check valve clearance though!

What not take some Wiseco's or other D16 VTEC slugs and shave .060" off the top so they are flush with the deck?

Re: Let's put the D15 rod issue to rest
 

Jon I was almost gonna post the same thing this morning. What is the most you can safely bore a d15 out to? Picking up a Z1 block to ---- around with for free and you can't pass that up since for some reason these don't show up that often. Any possibility of getting it to 81mm? You can always dream can you? Ever think of the b16 rods and supra pistons setup? Don't see why it wouldn't work in the d15b since crank journals are the same I think. You'd just have to knotch the block for the rods.

Re: Let's put the D15 rod issue to rest
 

What i was saying was you cant run the d15b aftermarket rods in the jdm d15b block. And yes if you go z6 rods and pistons you already see the problem has bone has shown but, If a company ran atleast 10 sets of pistons for the jdm d15b there would be the support for them Im sure just a matter of havin someone have them built and findin someone who will sell them

Re: Let's put the D15 rod issue to rest
 

D15B vtec rods ARE THE EXACT SAME Honda rods as the D16 rods.

So why are you saying you can't run them?

Z1 block uses a DX crank, 42mm rod bearings, not the 45mm like the D15B vtec.

You can safely bore a D series to 76mm before sleeving. After sleeve job the limit is 78mm, maybe 79mm on a grenade motor.

81mm was tried once on a sleeved motor, it never made it off the dyno before spliting the sleeves in NA form.

Re: Let's put the D15 rod issue to rest
 

Or run a MrGasket headgasket? The one with the .25 mm, .50 mm, and 1.00 mm layers you can stack?

Re: Let's put the D15 rod issue to rest
 

1mm = .039", stock Y8 crushes to about .035", no info provided from MrG when I emailed them.

Cheap way = 2 Y8 HG's

else Cometic.

Re: Let's put the D15 rod issue to rest
 

Good info guys.

So bottom line, the d15b rods are beefier than the d15b7 rods, and thus just as beefy as the d16z6 rods?

Re: Let's put the D15 rod issue to rest
 

Hmmm how would the vitara piston be in that since it gives already a low CR in a 1.6 block so maybe it would almost usuable in that d15b block? I dunno I'm just thinking out my ass. :1

Re: Let's put the D15 rod issue to rest
 

If I had a stock bore Vitara slug, I would mock it up.

Re: Let's put the D15 rod issue to rest
 

forgot who, but someone is running a set of vitaras in a jDM BEEtec d15b on this site.

Re: Let's put the D15 rod issue to rest
 

Jago, how much pounds did your d15b7 like ?

I've got a d15b2 overhere... and i'm just curious...

Re: Let's put the D15 rod issue to rest
 

I was saying you cant run the crower usdm d15b rods in a jdm d15b

Re: Let's put the D15 rod issue to rest
 

if it is a nonTEC or VTEC-E D15B you can.

Re: Let's put the D15 rod issue to rest
 

word

Re: Let's put the D15 rod issue to rest
 

8 psi on the .48/.60 is all she wrote. Tuned well by myself.

Re: Let's put the D15 rod issue to rest
 

But how healthy was the engine before? I still think b7's and B2's aren't that bad. It's not a megastrong engine but still can hang pretty good for quite some time on a good tune and healthy engine before hand.

Re: Let's put the D15 rod issue to rest
 

D15B7 with minor bolt-ons will put 115+ to the wheels.....just lacking a little midrange torque.

Stock mine was rated at 102 chp, I'm getting 145 chp on a 150k mile stock bottom end.

Re: Let's put the D15 rod issue to rest
 

I guess I'm just a d15 fan. I like underdog engines. Not to mention I usually get all of mine for free. 8)

Re: Let's put the D15 rod issue to rest
 

I just put a z6 intake mani on my b7 and man what a difference
cant wait for turbohf to ship my d16a6 cam

Re: Let's put the D15 rod issue to rest
 

add a Y8 cam gear, IHE and instant 130-135 chp.......

D15B7 like D16A6 needed the Z6 intake.........

Try to find a Crane 251-0012 cam for cheap, another good increase in power AND fuel economy.

Re: Let's put the D15 rod issue to rest
 

z6 manifold really helps the d15b7. Actually any 16 valve non vtec motor likes the z6 manifold. Ported is always good to

Re: Let's put the D15 rod issue to rest
 

I've been preaching it for 7+ years now..........

Re: Let's put the D15 rod issue to rest
 

I did that mod back in 98 when I was still in high school on my old sohc zc easy hp

Re: Let's put the D15 rod issue to rest
 

My d15b2 did good this weekend, N/A

106chp and nice torque, DPFI still.

MPFI will come on a short notice, and boost will ofcourse follow.

http://www.htn-y0.nl/htny0/t0n/eg4/t0n_dyno.jpg

Re: Let's put the D15 rod issue to rest
 

D16 cam? 1/2 tooth advanced?

Re: Let's put the D15 rod issue to rest
 

Responding to my post?

It's all stock motor.

Re: Let's put the D15 rod issue to rest
 

Reguardless.. a Stock D15/D16 rod is hard to keep from exiting the block over 240whp. Everytime someone trys to argue with me about it.. I just hold up my pinky finger and laugh. ;)

Re: Let's put the D15 rod issue to rest
 

The jdm d15b motor is cool and cheap but from someone who has owned about every stock d series swap known to man its not that great. I would go 1.6 but thats just me

Re: Let's put the D15 rod issue to rest
 

Just going to turbo the stock motor, I didn't think there would be much of a power increase using a d16z6 over a jdm d15b... I just wanted to know if they can handle roughly the same amount of abuse, since they are so similar internally?

Re: Let's put the D15 rod issue to rest
 

I ran an 80 shot on a customers car for over a year never had problems. I'm boostin mine in 2 weeks after I get caught up at work.

Re: Let's put the D15 rod issue to rest
 

liar :P

Re: Let's put the D15 rod issue to rest
 

Dont worry Jeff youll be the first one to know when its on LOL. Video/write up also