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Hi guys

So it seems the common issue of the exhaust manifold studs snapping have finally befallen my rb25

Since this is a common issue , Id imagine that it would be fairly easy to get uprated ones.

Where can I get better exhaust manifold studs , or would the proper nissan ones suffice?

How much should I expect to pay for them?

Thanks in advance

Cheers

I just recently did mine. I got mine from G7 which were Nissan OEM ones, they're high tensile steel. The only reason they snap is because they're 15 years old and they are exposed to high heat temps. So far so good, no complaints do so I would say just get the same. I think I payed about $60 for 12, so $5 each. I'd say do all of them at once as if you don't, expect more to break soon'ish anyway.

not sure if i want to get normal bolts

kudo motorsports have replied with this:

"1) Studs and nuts - $118.80 + $14.30 postage

2) Studs, nuts & new genuine Nissan washers/yokes - $184.80
*Postage on either would be $14.30.

With option 1 you'd simply have to reuse your current washers and yokes, of which there are 24.

The offered items are actually genuine Toyota units and are far superior to the items used by Nissan."

Is it worth forking out the extra dough?

Edited by tripsteady

the bloody bolts even break off on the rb30e/rb25de etc

imo its the hot/cold cyclic temp changes that cause the metal to fatigue and eventually break. not the heat on its own

Do the studs in the rb25 snap due to the 15yr age of them, or are they prone to snapping even when replaced because they are simply weak( trying to ascertain as to whether it's worth forking out the extra $60 for Toyota studs).

Only modest power, about 190kw at the wheels nothing to extreme, running 10psi

Irrespective of the stud material chosen, you need to closely inspect the clearances.

Use a straight edge to check for warp and if in doubt take the manifold to a machine shop.

Old manifolds such as these will have stress relieved themselves and you may now find there's nowhere for the stud to move in the slotted holes.

You'll notice the manifold holes at the centre cylinders are almost round whereas cylinders 2 and 5 have longer slots, 1 and 6 longer again.

The slots are to allow for manifold movement when hot and if the studs are locking the manifold, they'll snap off.

Dry fit up the manifold and check that the elongated manifold holes are not at the end of their slot. If they are you'll have to do some round file work.

Next check the spot facing region when the thick washer is installed.

The thick washer can get hung up on the spot facing and again if there's nowhere for the manifold to move, snapped stud..

A die grinder will soon relieve any excess.

While the manifold is off check the turbo studs are in tight as it's very common for them to loosen.

  • Like 1

Just call your local exhaust shop. Despite what many seem to think, skylines aren't much different to any car on the market and don't need any special treatment compared to any other car. they are just a sporty family car from the 90's. Pretty much every new car on the market has more technology under then bonnet than a skyline.

So so true. When i moved from my gemini to skyline i thought WOW im never going to understand all this new fangled 'electronics'. I now look at my sisters honda jazz and my skyline resembles my geminis simplicity in under the bonnet tech. LOL

Just call your local exhaust shop. Despite what many seem to think, skylines aren't much different to any car on the market and don't need any special treatment compared to any other car. they are just a sporty family car from the 90's. Pretty much every new car on the market has more technology under then bonnet than a skyline.

at least most of the electronics in skylines were there to run the thing

with all the electronics in new cars for "drivers aids" there must be a butt of things waiting to go wrong when these cars age

ok , from this i got that

- studs dont snap anymore often then any other 16yr old turbo car.

screw it , im getting uprated studs so i can sleep at night and never have to worry about this again. do it once , do it right.

it's pretty safe to say that in most instances, even using normal studs, most people won't own their car by the time it needs them replaced again, and in a lot of cases the engine would've needed to rebuilt by then

I don't think so. How often do you hear of people having problems with abs? Most of the modern driving aids are just glorified abs and traction control.

well i do think so. . .. park assist where the car turns the wheel and guides it in. .lane change assist. . . automatic braking when the car senses you are getting too close to the car in front of you. . the new toyota van i was driving yesterday has a projection of the area behind the van (on the rear veiw mirror)so you dont back into things .. these are just four things i can think of

so yeah. . a lot more electronics to crap itself when its old

no . . lane change assist uses radar. . you are correct ppl did say (in the eighties) that nobody would be able to fix cars with all the electronics on them and to an extent they are correct. . half the threads on this forum are about faulty/malfunctioning afms knock sensors vct not working , ecu issues, electronic speedos not displaying the correct speed etc etc

  • 4 weeks later...

I come from an industry that is all heat related. It has been common practice to put Nickel Antiseize on bolts and pipe threads which are subjected to high temperatures like these and I would include all the exhaust pipe bolts. The nickel antiseize helps to reduce the reduction of nickel in the parent metal (being burnt out) and also acts as a sheering point when undoing the bolts. This is probably the only case where using more is better. Don't us copper coat as it causes galvanic corrosion at elevated temperatures from the copper.

  • 6 years later...

Im changing exhaust manifold studs at the moment and brought a set from Kudos Motorsport.

But they look slightly different. See Pic. Top stud is the old stud removed. Bottom is new stud from kudos.20200805_161144.thumb.jpg.79a9ef18bfc1601756ecbd2432cc0f17.jpg

After trying to install the new stud and torque it, it didnt feel like it was stopping at the non threaded part and felt like it was just borrowing in deeper past the middle non threaded part.

With the fear of screwing up the threads in the head i stopped.

I then reinstall the old stud to check and it went in and stopped at non thread part and torqued up.

Is new stud expected to go a bit deeper or should it stop at the non threaded section?? 

What do you guys think??? 

 

 

 

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