Hi,
so i'm pondering building up my jdm d15b I have in my storage room...

not sure if I want to turbo it or go n/a,
well actually I am sure.. i'm sure I want to do both!! haha,
I want to go na really badly, but I already have a turbo kit and dont want to sell it..

anyways,
one of the biggest weaknesses on the dseries motors in their rods..
and i've heard of some people running LS rods before,

I couldnt find anything on it in a search(its kinda hard to look up LS)

whats it take to get those rods to work in a dseries motor,
and what are my limitations(if any) when using them?
could I use the piston of my choice?

thanks a bunch!!

 

That works for D16.

D15 it's Crower billet or custom.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rocket &raquo;</TD></TR><TR><TD CLASS="quote">That works for D16.

D15 it's Crower billet or custom.</TD></TR></TABLE>

what? really ! ****!
why

 

The D15 rod has a diff. big end bore and overall length.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rocket &raquo;</TD></TR><TR><TD CLASS="quote">The D15 rod has a diff. big end bore and overall length.</TD></TR></TABLE>

and the LS rods bore/length matches the d16?

I couldnt just takem to a machine shop and have them work some magic?

as you can tell I still need to do some learnin.. so fill me in!!
thnx

 

the Big End bore dia's and lengths of an LS and D16 rod are the same.

The LS rod has a slightly wider big end and takes a 21mm pin vs a 19mm (D16).

LS, D16 center-to-center length is 5.394"
LS, D16 B.E. Bore is 1.890"

LS B.E. Width is 0.935
D16 B.E. Width is 0.892

D15 center-to-center length is 5.279"
D15 B.E. Bore is 1.772"

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rocket &raquo;</TD></TR><TR><TD CLASS="quote">the Big End bore dia's and lengths of an LS and D16 rod are the same.

The LS rod has a slightly wider big end and takes a 21mm pin vs a 19mm (D16).

LS, D16 center-to-center length is 5.394"
LS, D16 B.E. Bore is 1.890"

LS B.E. Width is 0.935
D16 B.E. Width is 0.892

D15 center-to-center length is 5.279"
D15 B.E. Bore is 1.772"
</TD></TR></TABLE>

I could have sworn the LS and D16 both had a BE width of .935???

Could be wrong though, dont know much about SOHC's

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rick Solis &raquo;</TD></TR><TR><TD CLASS="quote">I could have sworn the LS and D16 both had a BE width of .935???</TD></TR></TABLE>
Nope I speak from experience, you have to take something like .019" off either side. I got my rods/pistons back from the machine shop then when I went to install them they were too wide so I had to put it on the grinder & take it off.

 

so definetely with the d15b, my only option would be aftermarket rods?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tad &raquo;</TD></TR><TR><TD CLASS="quote">so definetely with the d15b, my only option would be aftermarket rods?</TD></TR></TABLE>
that is correct, and unfortunetly most places charge a pretty penny for them

 

just go with aftermarket, then instead of worryin about oif ls rods will fit, your downtime wouldnt be as much?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mportbusta &raquo;</TD></TR><TR><TD CLASS="quote">just go with aftermarket, then instead of worryin about oif ls rods will fit, your downtime wouldnt be as much?</TD></TR></TABLE>

nah, its cheap oem or nuthn,

i'm goin nuthn,
oh well, maybe some day when i'm older and settled and have nothing better to do,
i'll build a motor..

for now it stays all sealed up

 

hold on hold on... not all D15' are the same. JDM D15B & D15Z1 (Vx) share the same rod length as D16Z6 and othe d16's, 137mm. The pistons are different, same bore but the d15B & Z1 are shorter to compensate for the longer rods. All other d15's have 134mm long Rods. I have d15B pistons & rods at home in a box as well as d16z6 pistons & rods. I will snap a pic when I get Home.

I am 100% sure on this, I have measured cause I was going to do the same thing with my D15B

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by egmike &raquo;</TD></TR><TR><TD CLASS="quote">hold on hold on... not all D15' are the same. JDM D15B & D15Z1 (Vx) share the same rod length as D16Z6 and othe d16's, 137mm. The pistons are different, same bore but the d15B & Z1 are shorter to compensate for the longer rods. All other d15's have 134mm long Rods. I have d15B pistons & rods at home in a box as well as d16z6 pistons & rods. I will snap a pic when I get Home.

I am 100% sure on this, I have measured cause I was going to do the same thing with my D15B
</TD></TR></TABLE>

so what you're saying then,
is that the d15b/z1 rods are in fact identical in length to the z6 rods...
AND i'm assuming that the problem with ls rods in 1.5's is the length,
WHICH would lead one to assume that LS rods would in fact work(with the same modification neccesary in a z6) in a d15b VTEC!!?

! ?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tad &raquo;</TD></TR><TR><TD CLASS="quote">

so what you're saying then,
is that the d15b/z1 rods are in fact identical in length to the z6 rods...
AND i'm assuming that the problem with ls rods in 1.5's is the length,
WHICH would lead one to assume that LS rods would in fact work(with the same modification neccesary in a z6) in a d15b VTEC!!?

! ? </TD></TR></TABLE>

Yup exactly.... I'm taking a pic now so you can see the d15b Vs d16z6

 

Well here is a pic with the D15B on the Left and D16z6 on the right, the pic isnt the best but they are the same length, the d15B pistons are slightly shorter



this is another alternative to LS Rods, they are D16A1 rods (compared against D16Z6)


They are ~3.5mm thicker than LS rods (LS rods are the same thickness as d16z6) and about 2 mm narrower than LS.

 

cool man, thanks for the pics,
what car is the d16a1 from?
the dimensions of the rod in the side view look different from the z6, or is it just cuz one rod is angled a bit?

they definetely look like they could handle some more power.

 

a6 rods are thicker yes, but made from a more brittle material i believe. perhaps mist bone will chime in.


m.

 

d16a1 is from 86-88 teg and yeah the side shot, the d16a1 rods are thicker

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tad &raquo;</TD></TR><TR><TD CLASS="quote">cool man, thanks for the pics,
what car is the d16a1 from?
the dimensions of the rod in the side view look different from the z6, or is it just cuz one rod is angled a bit?

they definetely look like they could handle some more power.</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dvious hatchie &raquo;</TD></TR><TR><TD CLASS="quote">a6 rods are thicker yes, but made from a more brittle material i believe. perhaps mist bone will chime in.


m.</TD></TR></TABLE>

Maybe so , but how would anyone know they are made from a more brittle material?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by egmike &raquo;</TD></TR><TR><TD CLASS="quote">Well here is a pic with the D15B on the Left and D16z6 on the right, the pic isnt the best but they are the same length, the d15B pistons are slightly shorter</TD></TR></TABLE>

Looks that way, but the D15 rods are supposed to be 134mm center to center whereas the D16's are 137mm. Dunno what's up with the picture.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by egmike &raquo;</TD></TR><TR><TD CLASS="quote">this is another alternative to LS Rods, they are D16A1 rods (compared against D16Z6)
</TD></TR></TABLE>

Not exactly. 86-87 D16A1 rods are like that, 88-89 are the same casting as the other 88+ D-series.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by egmike &raquo;</TD></TR><TR><TD CLASS="quote">They are ~3.5mm thicker than LS rods (LS rods are the same thickness as d16z6) and about 2 mm narrower than LS. </TD></TR></TABLE>

???

Got pictures of an LS rod next to the D16A1 unit? I had a set of LS rods next to a ZC, D16A6, and D16Z6 and I was pretty certain the LS were beefier in all dimensions. It was a stack of rods and I wasn't looking that closely.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by J. Davis &raquo;</TD></TR><TR><TD CLASS="quote">

Looks that way, but the D15 rods are supposed to be 134mm center to center whereas the D16's are 137mm. Dunno what's up with the picture.

Not exactly. 86-87 D16A1 rods are like that, 88-89 are the same casting as the other 88+ D-series.

???

Got pictures of an LS rod next to the D16A1 unit? I had a set of LS rods next to a ZC, D16A6, and D16Z6 and I was pretty certain the LS were beefier in all dimensions. It was a stack of rods and I wasn't looking that closely.</TD></TR></TABLE>

The D15 rods are 134 mm center to center but not on D15B & D15Z1 They are the same as D16Z6 and others at 137mm. I will get them pressed off next time I am at my buddys shop and then you will be able to see 100% with them laying flat. This is why the D15B/Z1 has a rod/stroke ratio of 1.62 (137mm/84.5mm= 1.62 ) and the other D15's are 1.58 stoke ratio (134mm/84.5mm)

Here are some pics to compare....

 

if using the stock d15b rod what oem piston will yeild around 10.5 cr?

 

interesting
so the d15b and z1 do in fact have the same rod length as the z6.

what makes them 1.5 then? the crank?

Question for you!
what do you know about d15b7 pistons?
they wouldnt work in the d15b would they.. if the rod length is so much longer on the d15b, then the b7 pistons would yeild WAY too much compression??

I'm curious about them because they are flat top pistons, and yeild higher comp in mini me setups.

thanks.

 

egmike, thank you.