My Vitara piston measurements

[slebidia]

So I did some skirt measurements comparing a Vitara to a PM3 and here's what I cam up with.

Vitara diameter = 2.9478
PM3 diameter = 2.952
difference = -0.0042

The service limit for a D-series is 2.9517
This means the Vitaras are 0.0039 to small in diameter.

So have anyone tried getting the piston skirts coated to lessen the slop?

[ryan89crx]

So I did some skirt measurements comparing a Vitara to a PM3 and here's what I cam up with.

Vitara diameter = 2.9478
PM3 diameter = 2.952
difference = -0.0042

The service limit for a D-series is 2.9517
This means the Vitaras are 0.0039 to small in diameter.

So have anyone tried getting the piston skirts coated to lessen the slop?i knew that the difference was a bit much.

i also made a thread a while back about getting the pistons coated, but after finding out the price through a few members that had done it, i was only about $40 short of getting a set of forged...

[slebidia]

i knew that the difference was a bit much.

i also made a thread a while back about getting the pistons coated, but after finding out the price through a few members that had done it, i was only about $40 short of getting a set of forged...

I just checked HPC they're local to me. To get the skirts coated on 8 (since I have 2 sets) would cost $160. So coated Vitaras with rings would cost me about $200 per set. That's not bad really. I asked how thick the coating was and he said about .001. I asked about putting on .003-.004 and he said it shouldn't be a problem. Maybe I'll give it a shot next paycheck.

[fjt]

Cool info..

so yours now will be double coated.

[ryan89crx]

I just checked HPC they're local to me. To get the skirts coated on 8 (since I have 2 sets) would cost $160. So coated Vitaras with rings would cost me about $200 per set. That's not bad really. I asked how thick the coating was and he said about .001. I asked about putting on .003-.004 and he said it shouldn't be a problem. Maybe I'll give it a shot next paycheck.thats a damn good price! i was told $160 for 4, which would be roughly $300 for a set. i can get SRPs through Jegs for $340(no rings though :sad:)

[hectorcuper]

get the .5 mm oversized vitara pistons and bore out the block to the right diameter.

[slebidia]

get the .5 mm oversized vitara pistons and bore out the block to the right diameter.

No.

[hectorcuper]

oke, so you guys are saying the vitara pistons are no good?

[fjt]

i wouldnt say that..since ppl have made over 300whp with them(as much as 354whp so far).

[slebidia]

oke, so you guys are saying the vitara pistons are no good?

I'm not saying they're no good. I'm just trying to sold the piston slap issues someother have reported. It gets pretty cold here in the winters so I'd like to close up the piston to wall gap before putting these in my daily.

[hectorcuper]

oke, then i guese i'll do it my way with oversized vitara's.

[slebidia]

I have my Vitaras coated. The lowest part of the skirt now measures 2.950. Still a little shy of where I would like things to be but I'll run them and see what happens anyways.

[inh]

arent they supposed to be a lil small because they'll expand more when warm?

[slebidia]

arent they supposed to be a lil small because they'll expand more when warm?

They're not forged so they really shouldn't be loose at all.

[ryan89crx]

was the price the same as you posted earlier?

[slebidia]

was the price the same as you posted earlier?

$160 for all eight. Well maybe $192. I didn't agree with their pricing model so he charged me $160 while I was there. We'll see if my bank statement reflects that.

[KyleVA]

This makes me more and more skeptical about Vitaras..

but seriously.. who has had these pistons crap out on them in their daily? From what I've read they can take abuse.

[lsturbohatch10]

is this the reason they give you the diesel sound? i was going to run them, but i got those SRPs for 220. so i jumped on it.

[inh]

ah ok i thought they were forged pistons. disregard :p

*goes back to the NA forum where I belong*

[Normworldhero]

I don't have any stinking diesel sound with mine. Just 130's compression when they're cold and 140's when everything's warmed up.

[kyle h.]

is there a rough (sleazy) way to get the compression ratio from compression test results? 140psi seems low for ~8.5:1

[Normworldhero]

is there a rough (sleazy) way to get the compression ratio from compression test results? 140psi seems low for ~8.5:1

Dunno, I tried searching through some of FJT's old posts, but didn't find the compression list that he posts occasionally. This motor is a stock y7 block, head gasket, & head, with vitaras on eagle rods so I'm not sure if it's supposed to yield 8.5 or lower.

[KyleVA]

I think 8.5 is about right to be honest. Its somewhere on Honda-Tech if you just search "Vitara" in archived content.

Mannn, I think I'm just going to go forged. I was really thinking about Vitaras but I'm not really doing a "budget build." So there's really no good reason not to go forged.

[fjt]

My Y7 yielded 160 psi across all 4 cylinders whenthe pistons where just installed... Couple of months later with some carbon build up it was 165psi on all 4

Vitaras with Eagle rods

[Normworldhero]

My Y7 yielded 160 psi across all 4 cylinders whenthe pistons where just installed... Couple of months later with some carbon build up it was 165psi on all 4

Vitaras with Eagle rods

Interesting, maybe the headgasket I have is thicker than it should be?

The good news is at least they all have consistent pressure between them, no drastic differences between the bunch.

[slebidia]

I compared piston wobble with a bare Vitara piston in a few different blocks last night. Some of my blocks had barely any wobble at all while other I knew would result in enourmous amounts of piston slap.

I think I need a better way to measure cylinder wall diameters. ;)

[b20vtec]

does anyone know what the OEM No, & sizes of these pistons?

[kyle h.]

wtf? they are listed at the beginning of this post?

[b20vtec]

what about the part number?

[slebidia]

what about the part number?

Have you tried http://www.d-series.org/forums//search.php?

[b20vtec]

Have you tried http://www.d-series.org/forums//search.php?

oh thanks i couldn't find that

[fjt]

g16b pistons


I used the Y7 oem HG