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Discussion Starter #1
I have been toying with the idea of building my next bottom end using LS rods. I know the steps needed to be taken to make them fit into a D16.

Let's ignore money for a moment and just think of this as a practical exercise in engineering.

I believe using an LS rod that has been rebushed to accept a stock cast piston can be used to achieve more than 250whp from a D16.

Both oem pistons and vitara's are cast pistons. The advantage the vitara has is the forged rod that normally ride beneath it in place of the pencil thin D16 rods. I know more strength can be achieved using a set of LS rods in place of the pencil thin D16 rods.

Now vitara's other advantage is a severe drop in compression. But recent kits have bumped that compression up into the neighborhood of ~8.5-9.0:1. Around about the same compression can be achieved mix matching pistons and head combo's.

Anyone's thoughts on this...and like I said ignore the cost aspect of this build for the moment.
 

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done it before $8 per brass insert for vitara (full floating)
about $15-20 per big end rod shave to fit onto d16 crank. I done this locally at Crower but im sure any machine shop could do it for you also..
 

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Discussion Starter #3
done it before $8 per brass insert for vitara (full floating)
about $15-20 per big end rod shave to fit onto d16 crank. I done this locally at Crower but im sure any machine shop could do it for you also..
See I know its been done with vitara's. I want to do this with a oem cast piston. Then push the motor to over 250whp.

A stock LS can handle ~300whp before things start to get broken. I believe a D16 can achieve similar numbers with the LS rods.
 

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See I know its been done with vitara's. I want to do this with a oem cast piston. Then push the motor to over 250whp.

A stock LS can handle ~300whp before things start to get broken. I believe a D16 can achieve similar numbers with the LS rods.
the problem is the wrist pin size. you would need a thicker bushing (smaller internal diameter) to fit the stock d series pistons.
 

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what do you mean by leave cost out of it??
unless your stuck in a rule book put a set of quality rods in there and call it a day imo...

by the time you acquire the parts then modify them you spent your money for a decent set of performance rods.
 

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the artist formerly known as drexelstudent11
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what do you mean by leave cost out of it??
unless your stuck in a rule book put a set of quality rods in there and call it a day imo...

by the time you acquire the parts then modify them you spent your money for a decent set of performance rods.
this is also true.
 

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Anyone's thoughts on this...and like I said ignore the cost aspect of this build for the moment.
the problem is the wrist pin size. you would need a thicker bushing (smaller internal diameter) to fit the stock d series pistons.
This ^

what do you mean by leave cost out of it??
unless your stuck in a rule book put a set of quality rods in there and call it a day imo...

by the time you acquire the parts then modify them you spent your money for a decent set of performance rods.
and this ^^


If your already opening up the case, you might as well do a full build. Everyone keep talking vitara this and that.. theres other options of pistons out there.. If it were me, Id shoot for 10.5CR for NA or boost if I were looking to build the bottom.
 

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Discussion Starter #8
the problem is the wrist pin size. you would need a thicker bushing (smaller internal diameter) to fit the stock d series pistons.
I know all that, already talked to crower about the bushings.

what do you mean by leave cost out of it??
unless your stuck in a rule book put a set of quality rods in there and call it a day imo...

by the time you acquire the parts then modify them you spent your money for a decent set of performance rods.
While I tend to agree, somehow someone somewhere thought it would be a good idea to use the vitara piston.


This ^



and this ^^


If your already opening up the case, you might as well do a full build. Everyone keep talking vitara this and that.. theres other options of pistons out there.. If it were me, Id shoot for 10.5CR for NA or boost if I were looking to build the bottom.
I'm already close to the CR now.
 

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the artist formerly known as drexelstudent11
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it's because they're floating pin and cheap, no other reasons.

I think a d15b2/b7, cxracing rods, and floating pin pg6bs would be a hot ticket build on the cheap. you could seriously embarrass some people with your little d15
 

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Discussion Starter #11 (Edited)
d15b2/b7, cxracing rods, and floating pin pg6bs=tits
&
probably cheaper
Now I understand....Def didn't read nearly enough before making this post.

My understanding of it was the bronze bushings sole purpose was to bring the small end down in size to fit the d16 sized wrist pin, still being a press fit style pin, not a floating. I now see the error of my ways. In the little research I have done so far seems like the only oem style cast pistons that are being made for floating pin are the ZC/p29's and the pg6's.

In order to get the compression I am after I would need to use a thicker headgasket and take away some of the quench.

Thoughts on this setup

D16y8
LS rods
P29's
cometic .080 HG

CR will be ~10:1
:::Goes back into garage to tinker more:::
 

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the artist formerly known as drexelstudent11
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Now I understand....Def didn't read nearly enough before making this post.

My understanding of it was the bronze bushings sole purpose was to bring the small end down in size to fit the d16 sized wrist pin, still being a press fit style pin, not a floating. I now see the error of my ways. In the little research I have done so far seems like the only oem style cast pistons that are being made for floating pin are the ZC/p29's and the pg6's.

In order to get the compression I am after I would need to use a thicker headgasket and take away some of the quench.

Thoughts on this setup

D16y8
LS rods
P29's
cometic .080 HG

CR will be ~10:1
:::Goes back into garage to tinker more:::

stop, no, this is bad. This combo won't make power, that huge gasket is killing your quench, and p29s have that huge bump for compression that will divide up your combustion chamber and make the flame go further than it wants to or should.

I also don't like Y8 heads but if that's what you've got that's what you've got.
 

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Discussion Starter #13
stop, no, this is bad. This combo won't make power, that huge gasket is killing your quench, and p29s have that huge bump for compression that will divide up your combustion chamber and make the flame go further than it wants to or should.

I also don't like Y8 heads but if that's what you've got that's what you've got.
I was wondering about the quench and flame travel on that particular combo. Figured it wouldn't work out very well. Was my last ditch effort at trying to use LS rods with a cast piston.
 

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I know all that, already talked to crower about the bushings.
Did they tell you that while pressing the wrist pin into place, you might move the bushing and cause the piston to bind on the rod?

the bushings for floating pin pistons are to act completely different than pressed pin pistons.

as mentioned above, floating wrist pins are one of the things that make them attractive for boost.
 

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Discussion Starter #16
Did they tell you that while pressing the wrist pin into place, you might move the bushing and cause the piston to bind on the rod?

the bushings for floating pin pistons are to act completely different than pressed pin pistons.

as mentioned above, floating wrist pins are one of the things that make them attractive for boost.
Yeah, see this was my beyond my noobish learn'ed brain at the time. I have now educated myself more and while still pondering the idea of using these rods in a motor, they are less attractive to me.
 

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Yeah, see this was my beyond my noobish learn'ed brain at the time. I have now educated myself more and while still pondering the idea of using these rods in a motor, they are less attractive to me.
If your giving up on this idea maybe try cx racing rods with oem honda pistons? I feel that the oem pistons can handle just as much as vitara pistons.
 

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Discussion Starter #18
If your giving up on this idea maybe try cx racing rods with oem honda pistons? I feel that the oem pistons can handle just as much as vitara pistons.
I feel this way as well the main issue is getting the compression were I want it. Wanting to run pump gas on this car so 11+ cr isn't really an option with boost. Need to talk to some machinist about the actual cost of getting a press fit piston cut to accept spirolox or something similar. Haven't given up just yet.
 

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Discussion Starter #20
cost me 80 out the door at a shop in Illinois at NAC racing engines in 2006

I have heard rumors of it being done for half that
This opens up some new doors....will look into it, because for the price I got the rods for it wouldn't be too bad on the pocket to do this now.
 
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