I recently received a set of 75.5mm YCP Vitara pistons from fjt. I am very pleased with the quality and exactness of these pistons.

I got out my micrometer set and measured every single one of them. They were all exactly the same:

<u>Top:</u> 2.96 in. (75.184 mm.)
<u>Bottom:</u> 2.969 in. (75.4126 mm.)

In the past, people just got 75 mm. Vitaras and put up with whatever cylinder to wall clearance they got. It was usually too big, anywhere to as large as .008 in. While this worked for alot of people, and put down some extremely impressive numbers for a $130 set of pistons, it is certainly not optimal. Piston slap, over time, would surely hinder the motors longevity.

So, now that these 75.5 mm. Vitaras are available, the question comes to mind about what the proper cylinder to wall clearance is.

There is some good work being done at TurboD16 ( http://www.turbod16.com/viewtopic.php?f=3&t=35352 ), but I thought I'd post it up here so that we could get some more speculation/answers.

 

I would like to know too. I will be starting my vitara build soon as well.

 

I will be running two or three thou clearance on mine.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">While this worked for alot of people, and put down some extremely impressive numbers for a $130 set of pistons, it is certainly not optimal. Piston slap, over time, would surely hinder the motors longevity.
</TD></TR></TABLE>

Just for reference... I've got over 25k+ miles on my stock bore Vitara build. Just as noisy as the day it started... burns NO oil.

 

i replied to your turbod16 thread...i think you will be more than happy with a .003-.004 p2w clearance.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fast2camciv &raquo;</TD></TR><TR><TD CLASS="quote">i replied to your turbod16 thread...i think you will be more than happy with a .003-.004 p2w clearance.</TD></TR></TABLE>

thats what i plan on setting my piston to wall clearance to when i start my vitara build later down the road......now this .003-.004 piston to wall clearance will work on 75mm vitaras as well correct?

 

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

Just for reference... I've got over 25k+ miles on my stock bore Vitara build. Just as noisy as the day it started... burns NO oil.</TD></TR></TABLE>

Awesome.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fast2camciv &raquo;</TD></TR><TR><TD CLASS="quote">i replied to your turbod16 thread...i think you will be more than happy with a .003-.004 p2w clearance.</TD></TR></TABLE>

That's what people are starting to lean toward, including me.

.0035 sounds like the way to go.

 

I read somewhere that it should be .001 for every 100whp youre shooting for.

BTW: The next batch of 75.5mm is arriving in around 3 weeks and im taking advanced orders.

 

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

thats what i plan on setting my piston to wall clearance to when i start my vitara build later down the road......now this .003-.004 piston to wall clearance will work on 75mm vitaras as well correct?</TD></TR></TABLE>
well yea it will work if your bores are nice...you are kinda at the mercy of the cylinder dimensions on a 75mm piston. thats why jfk ran .008 on his, his cylinders were just out of tolerance, but he said *** it lol....it is what it is on a 75mm bore.

 

Well, BUMP for another topic of debate: ring gap.

Since we now have 75.5mm pistons, we need to decide a proper ring gap. Any thoughts? Should they be different for a 75.5 versus a regular 75?

Some topics on TurboD16: http://turbod16.com/viewtopic....hilit=

http://turbod16.com/viewtopic....a+gap

 

UP for ring gap.

 

from what I gathered, the rings were gapped for the pistons themselves. I know why it would be a concern though. I will be getting set for myself; I am building a D15B (JDM) for my EJ.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JaredKaragen &raquo;</TD></TR><TR><TD CLASS="quote">from what I gathered, the rings were gapped for the pistons themselves. </TD></TR></TABLE>

Yeah, but you have to make sure that you have the right gap.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">UP for ring gap.</TD></TR></TABLE>

 

I dont know how much vitara pistons expand but from personal experience I would go with the larger gap. .017 to .019 with work.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Newt Dog &raquo;</TD></TR><TR><TD CLASS="quote">I dont know how much vitara pistons expand but from personal experience I would go with the larger gap. .017 to .019 with work. </TD></TR></TABLE>

For only 300 hp?

 

What about us guys that need to go like 40 over? Is there a 76mm Vitara?

I might have to get a fresher block...*ugh*

Is there a 76mm Vitara?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vectorsolid &raquo;</TD></TR><TR><TD CLASS="quote">What about us guys that need to go like 40 over? Is there a 76mm Vitara?

I might have to get a fresher block...*ugh*

Is there a 76mm Vitara?</TD></TR></TABLE>

yes there is! Contact "fjt" to get some! AWESOME prices!

 

covered, got 76's.

 

Tippyman,

Question for you. I think i mixed up my 2nd and top rings lol. Are your 2nd rings thicker and darker then top rings? Also i measured the gaps that i got with the rings sent and got the following. *make note that they may be backwards depending on if i mixed them up or not.*

Rings sent to me by FJT are the following:

Nippon Piston Rings
Suzuki G16 SJ413
SWS20142ZZ 0.50
AE DIA 75.000mm G266B

Top Ring: .254mm (.010")
2nd Ring: .432mm (.017")

The gaps above were the tighest feeler gauge i could fit between the gap.

 

im running 76mm vitaras and im currently running n/a for now...uhh...i forgot what my clearence was gotta find my notes.

 

bump!!!!!!

 

ttt

 

I'm thinking about going .019 for top and for .020 for the bottom.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">I'm thinking about going .019 for top and for .020 for the bottom.</TD></TR></TABLE>

your talking about ring gap right? isnt that what oem honda specs call for?