Jump to content
SAU Community

Recommended Posts

Just an update, I talked to my old builder **** ***** Engines today and he agreed to rebuild my motor free of cost excluding parts....hmmn would u trust them again?-I think not.

Peter @ ADVAN is going to gap my rings and check bottom end clearance's for me before I put it back together. At least I'll know it is perfect. ADVAN also stamp the block which should help at Re-sale time. My head needs new valve guilds aswell....I'm running out of dollars fast...grrr

  • Replies 148
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

Just an update, I talked to my old builder **** ***** Engines today and he agreed to rebuild my motor free of cost excluding parts....hmmn would u trust them again?-I think not.

that states he knew he ***d up. I'd still be ringing C.A. and tell em you want a refund for parts and labour.

I wouldve laughed if he offered to build it for free minus parts...labour is sfa compared to the thousands youve probably already spent.

Good luck with the new motor anywaqy :huh:

Matt,

Glad to see its coming together, be it at a cost - I feel your pain!

Here are some picks of my new CP's which from memory are the same pistons you opted for now?

Are you using 86.5 mm pistons or 87 ? What clearence , piston to bore ?

Replacing rods as well ?

Edited by wrxhoon
Are you using 86.5 mm pistons or 87 ? What clearence , piston to bore ?

Replacing rods as well ?

Hi Jerry,

87mm, not sure on clearances, was leaving that to the engine builder.

Retaining standard rods, but having them prepped, shot peened and strengthened.

Hi Jerry,

87mm, not sure on clearances, was leaving that to the engine builder.

Retaining standard rods, but having them prepped, shot peened and strengthened.

I had 87 mm bore in my old 33 and 8.7 to 1 comp , she was a quick stock car , 11.7 @121 mph with just N1 turbos and power f/c .

So you should have a very quick car if you keep the compression up .

Good luck with it Nick .

wrxhoon,

you might be able to answer this for me: is the slight increase in volume (comparing 86.5 to 87) worthwhile? I would have thought going the smallest over bore over stock (86mm to 86.5mm) would be the way to go in order to retain nice thick walls, and the scope for another rebuild should the need arise (a bit pessimistic i know). also wouldn't the smaller bore help with the CR or is it easily rectified with different piston design or head work?

cheers :D

....shot peened and strengthened.

Sorry for being a sticker for details...but it doesnt actually strengthen the rod...does it???

My understanding is that all it does is remove imperfections and surface defects meaning you are minisming the instance of failure due to their weakest points...not strengthening them over and above the norm.

wrxhoon,

you might be able to answer this for me: is the slight increase in volume (comparing 86.5 to 87) worthwhile? I would have thought going the smallest over bore over stock (86mm to 86.5mm) would be the way to go in order to retain nice thick walls, and the scope for another rebuild should the need arise (a bit pessimistic i know). also wouldn't the smaller bore help with the CR or is it easily rectified with different piston design or head work?

cheers :D

I would only go to 86.5 given the option ( if i could clean the bore with .5 mm ) but when i rebuild mine a couple of years ago i didnt think i could get away with 20 to thou so to be sure i went 40 thou.

walls are thick enough with 87 mm bore even for highly moded engines .

Bigger bore will give you higher comp if everything else stays the same , piston pin height , h/gasket block and head .

You can increase comp by using a thinner h/gasket and or decking the cil head just as easy .

.5 mm extra bore will give you 30cc extra so you have a little more capacity as well but its only very little gain like 1.2%.

Sorry for being a sticker for details...but it doesnt actually strengthen the rod...does it???

My understanding is that all it does is remove imperfections and surface defects meaning you are minisming the instance of failure due to their weakest points...not strengthening them over and above the norm.

Agree with that , if i wanted stronger rods i would change them,

but each to their own .

Sorry for being a sticker for details...but it doesnt actually strengthen the rod...does it???

My understanding is that all it does is remove imperfections and surface defects meaning you are minisming the instance of failure due to their weakest points...not strengthening them over and above the norm.

Shot peened AND strengthed (i.e crygenically treated etc) - Geez read the post will you tapas boy :D

I am well aware that shot peening itself isnt a strengthening process.

Shot peened AND strengthed (i.e crygenically treated etc) - Geez read the post will you tapas boy :D

I am well aware that shot peening itself isnt a strengthening process.

Sure the freezing will make them stronger and the shot peening helps as well Nick , it all depends on what you are looking for though , stock rods are very good and they dont fail with moderate mods but rod bolts do .

Matt,

Glad to see its coming together, be it at a cost - I feel your pain!

Here are some picks of my new CP's which from memory are the same pistons you opted for now?

cppiston.jpg

cppiston2.jpg

yep, same ones. I took a few pics of the vennolia's beside the CPs but they didn't come out to clear... The piston skirt on the CP's are at least 1mm thicker. The Vennolia's looked the same thinkness as the stock pistons- 2.12mm. The Vennolia's had thicker ring lans a thinner rings... I'll try the pic ...I would definately get the spirolock grooves machined deeper and use wire or circlips! if using vennolia's

post-2338-1125306506.jpg

wow! the piston on the right has much thicker ring lands. i wonder which is preferable, thicker rings, or thicker lands?

wrxhoon, thanks for the explanation on that. it's something i have often wondered about as i have seen people go to 86.5 where as some jumps straight to 87mm.

Shot peened AND strengthed (i.e crygenically treated etc) - Geez read the post will you tapas boy :(

I am well aware that shot peening itself isnt a strengthening process.

Ok, again from my reading and understanding of metallurgy, you are not increasing the strength of the basic metal used in the casting of the std rods. You are improvong the grain structure to remove imnperfections....so just liek shot peening you are removing the weaknesses, not makign them stronger then the basic metallurgy and casting allows....

its a matter of as strong as its weakest link and you are improving the weakest areas

  • 2 weeks later...
  • 1 month later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Hi, SteveL Thank you very much for your reply, you seem to be the only person on the net who has come up with a definitive answer for which I am grateful. The "Leak" was more by way of wet bubbles when the pedal was depressed hard by a buddy while trying to gey a decent pedal when bleeding the system having fitted the rebuilt BM50 back in the car, which now makes perfect sense. A bit of a shame having just rebuilt my BM50, I did not touch the proportioning valve side of things, the BM50 was leaking from the primary piston seal and fluid was running down the the Brake booster hence the need to rebuild, I had never noticed any fluid leaking from that hole previously it only started when I refitted it to the car. The brake lines in the photo are "Kunifer" which is a Copper/Nickel alloy brake pipe, but are only the ones I use to bench bleed Master cylinders, they are perfectly legal to use on vehicles here in the UK, however the lines on the car are PVF coated steel. Thanks again for clearing this up for me, a purchase of a new BMC appears to be on the cards, I have been looking at various options in case my BM50 was not repairable and have looked at the HFM BM57 which I understand is manufactured in Australia.  
    • Well the install is officially done. Filled with fluid and bled it today, but didn't get a chance to take it on a test drive. I'll throw some final pics of the lines and whatnot but you can definitely install a DMAX rack in an R33 with pretty minor mods. I think the only other thing I had to do that isn't documented here is grind a bit of the larger banjo fitting to get it to clear since the banjos are grouped much tighter on the DMAX rack. Also the dust boots from a R33 do not fit either fyi, so if you end up doing this install for whatever reason you'll need to grab those too. One caveat with buying the S15 dust boots however is that the clamps are too small to fit on the R33 inner tie rod since they're much thicker so keep the old clamps around. The boots also twist a bit when adjusting toe but it's not a big deal. No issues or leaks so far, steering feels good and it looks like there's a bit more lock now than I had before. Getting an alignment on Saturday so I'll see how it feels then but seems like it'll be good to go       
    • I don't get in here much anymore but I can help you with this.   The hole is a vent (air relief) for the brake proportioning valve, which is built into the master cylinder.    The bad news is that if brake fluid is leaking from that hole then it's getting past the proportioning valve seals.   The really bad news is that no spare parts are available for the proportioning valve either from Nissan or after market.     It's a bit of a PITA getting the proportioning valve out of the master cylinder body anyway but, fortunately, leaks from that area are rare in my experience. BTW, if those are copper (as such) brake lines you should get rid of them.    Bundy (steel) tube is a far better choice (and legal  in Australia - if that's where you are).
×
×
  • Create New...