Valve Noise RB25DET NEO

[DTT_Eruc]

3 minutes ago, admS15 said:

Well you definitely need a decent gasket then. Still, i wouldn't skip out on at least skimming the head and copper spraying the hg. Will at least give it a decent chance of sealing properly.

tomei 87 1.2mm on the stock bore(86).... well only until i see whats up with the head ill know what to do from there on..... dam why cant i just drive as is lol been working on this project 2 1/2 years now..... 

[Dose Pipe Sutututu]

2 minutes ago, DTT_Eruc said:

how much psi can the stock head studs hold for?

Some have done 400kW+ with everything OEM just ARP headstuds.

However you'll be silly not to replace it with a Tomei HG if the head is off.

[DTT_Eruc]

Just now, Dose Pipe Sutututu said:

Some have done 400kW+ with everything OEM just ARP headstuds.

However you'll be silly not to replace it with a Tomei HG if the head is off.

well if i do the HG since am there having no choice ill like to use the stock head studs till even if is not big amount of boost just want the car moving for now.... cause installing the arps wouldnt be hard doing after wards 

[admS15]

Much easier to do it now while you there. Do it once, do it properly. Especially since you're talking 600hp.

[Dose Pipe Sutututu]

Don't be tight, get the Tomei HG and ARP studs.. then do it all at the same time.

Torque it down properly once and forget about it.

[Kinkstaah]

I would also say "600hp on stock internals I just want to get it running while I am saving up for XYZ" is a disaster waiting to happen.

People absolutely have made 350-400kw on stock internals, for 'years' but lets be real here, you'd only want to be doing that if you already have a budget and ideally a second motor/rebuilt motor purchased, and ready to swap in the day it all goes bang.

The old adage re: GTR's and "Buy a GTR, have budget for rebuild to happen" does also apply to the RB25's of all variants too.

[DTT_Eruc]

48 minutes ago, Kinkstaah said:

I would also say "600hp on stock internals I just want to get it running while I am saving up for XYZ" is a disaster waiting to happen.

People absolutely have made 350-400kw on stock internals, for 'years' but lets be real here, you'd only want to be doing that if you already have a budget and ideally a second motor/rebuilt motor purchased, and ready to swap in the day it all goes bang.

The old adage re: GTR's and "Buy a GTR, have budget for rebuild to happen" does also apply to the RB25's of all variants too.

ahhhh yes my dear friend it IS a disaster waiting to happen... is it my daily driven car? No it isnt.. am i planning on hammering it everytime? maybe,maybe not.....  even if it makes 600 or even close to it does mean am putting my head on a block hoping it last forever.... what ill like is for the engine to at least give me a span time of 2 years so that i can gather all the essentials of having a properly built rb... so maybe 600 is a target but in reality ill go whats best for the engine at this moment .... so as you said it has been done for those with the luxury of spares or rebuilt.. for me once its up and running from there is buy abcdefg etc etc lol but i got u bud

 

[Dose Pipe Sutututu]

@DTT_Eruc just relax man, we are all here to help

Let's put it this way, I wouldn't reuse the OEM Nissan head bolts. If I had to use the OEM Nissan head bolts, they would be brand new.

They're Torque to Yield head bolts.

If the head is coming off, put in a Tomei headgasket and ARP headstuds, torque them to spec and push the motor till something goes bang - however the Tomei HG and ARP headstuds would be reusable items, so nothing is lost.

[DTT_Eruc]

2 minutes ago, Dose Pipe Sutututu said:

@DTT_Eruc just relax man, we are all here to help

Let's put it this way, I wouldn't reuse the OEM Nissan head bolts. If I had to use the OEM Nissan head bolts, they would be brand new.

They're Torque to Yield head bolts.

If the head is coming off, put in a Tomei headgasket and ARP headstuds, torque them to spec and push the motor till something goes bang - however the Tomei HG and ARP headstuds would be reusable items, so nothing is lost.

lol highly appreciate the patients and advice... head gasket no problem was just a bit optional on going on the arp but ill have no choice but to do so...... all this was really planned on the next motor build i had in mind ....... 

[DTT_Eruc]

9 minutes ago, Dose Pipe Sutututu said:

@DTT_Eruc just relax man, we are all here to help

Let's put it this way, I wouldn't reuse the OEM Nissan head bolts. If I had to use the OEM Nissan head bolts, they would be brand new.

They're Torque to Yield head bolts.

If the head is coming off, put in a Tomei headgasket and ARP headstuds, torque them to spec and push the motor till something goes bang - however the Tomei HG and ARP headstuds would be reusable items, so nothing is lost.

is it safe to purchase second hand arp head bolts just saw a buddy of mine having them for sale

[Dose Pipe Sutututu]

13 minutes ago, DTT_Eruc said:

is it safe to purchase second hand arp head bolts just saw a buddy of mine having them for sale

generally yes, make sure everything is there (studs, washers, nuts) and when you're torquing them down make sure you use assembly lube to get the right torque values - as per ARP.

 

[DTT_Eruc]

On 3/7/2019 at 7:38 PM, Dose Pipe Sutututu said:

generally yes, make sure everything is there (studs, washers, nuts) and when you're torquing them down make sure you use assembly lube to get the right torque values - as per ARP.

 

i forgot to ask ... if am using a tomei gasket which they only sell for 87mm bore and up,am i safe using it with stock bore of 86mm? and also do i have to skim the head to use there 1.2mm thick gasket. i was just gonna clean the head and block as perfect as possible... 

[Dose Pipe Sutututu]

You'll be fine, very common to run a 87mm on a 86.5mm or 86mm more.

Make sure the head and block are spotless, use brake cleaner. If you have the option to skim the head even better!

[DTT_Eruc]

On 3/14/2019 at 3:46 PM, Dose Pipe Sutututu said:

You'll be fine, very common to run a 87mm on a 86.5mm or 86mm more.

Make sure the head and block are spotless, use brake cleaner. If you have the option to skim the head even better!

Sooooooo... Just an update, i happened today got time to put back everything together and decided to do a compression test.... from Cyl 1 to 5 read 120 to 125 psi and for Cyl 6 reads 50... Jackpot of my problem lol but ik i still gotta take of the head.... 

[DTT_Eruc]

I know  the post is out dated a bit but for those who contributed on there ideas/solutions just wanted to update yall once again.. Decided to find the strength and patients to pull off the head and BOOM!  Valve #11 was surely the issue but strangely enough the valve is bent very slight so slight its hard to pick up in one glimpse. Also saw no contact on the piston and valve #12 seems to be ok thus far... Still leaves me to thinking  HOW did that happen. 

[KiwiRS4T]

Dunno but while you have the head off ideally get it crack tested but at least put a straight edge on it.

[GTSBoy]

2 hours ago, DTT_Eruc said:

valve is bent

Yay.  Finally a problem is something that was suggested, and not some other random crap!