Banjo Bolt Thread Sizes

[agentx]

Guys I'm in a tough spot and need some quick guidance - My turbo install is stuck because of banjo bolts.

I need to know what size the water return on an RB20 block is for the banjo bolt as well as what it is on the RB25 stock turbo for water feed.

desperate! please help

From what i've read, here's what i've found but i need someone to confirm this so I don't waste $50 from pirtek on another incorrect size bolts!

Water return on the rb20 block is M16x1.5, can't find any size for the water feed to the rb25 turbo

thanks for your help fellas

[zebra]

Water feed on the 25 turbo is 18x1.5 iirc

[agentx]

Water feed on the 25 turbo is 18x1.5 iirc

Thanks Zebra - appreciate the quick response, as soon as someone confirms the water return for rb20 blocks, I'll go to pirtek (probably tomorrow) and hopefully they'll exchange both banjo's without argument (i have receipts etc)

Cheers

[The Dan]

The block side should be 14x1.5 and the turbo itself should be 18x1.5 as zebra said

19mm spanner fits the block one and 22 or 24 on the turbo one.

[agentx]

thanks for the spanner sizes ... so thats one out of the way and two ideas for the water block side, would nissan know the exact size if i call them?

Also just thought, it it a good idea to get these two bolts from repco (not banjo, just normal) to check the size?

Edited November 24, 2011 by agentx

[The Dan]

No they won't know.

I'll head down to my bolt bucket now and grab one and measure it for you.

[The Dan]

Hazah

Small one for the block is 14 x 1.5 and large one for factory turbo is 18 x 1.5.

I measured both on my thread gauge

[agentx]

Hazah

Small one for the block is 14 x 1.5 and large one for factory turbo is 18 x 1.5.

I measured both on my thread gauge

And you uploaded a picture - you sir, are a legend. Wish i could return the favor! Thanks a million! off to pirtek tomorrow! quick question, what block was it? what year rb20? hopefully they're not different

btw, do I just tell them M14 x 1.5 or does that iirc bit need to be included (not too savvy on the bolt measurement schemes).

Edited November 24, 2011 by agentx

[discopotato03]

I'm reasonably sure that VL turbos used the same size banjo bolts at least at the turbo end . If you can confirm OE ones work because they are the right length . Good second hand ones do the job too so import wreckers can be good places to look .

A .

[agentx]

Thanks mate - im gonna goto repco tomorrow and get two bolts (M14 x 1.5 and M18 x 1.5) just to double check the size and then goto pirtek and swap the ones i got yesterday and hopefully be on my way!

[agentx]

ok - so I can 100% confirm that M14 and M18 are WAY too big both for the turbo and the block for an rb20. Three trips to pirtek and I'm over it. I've just gone to the wreckers and luckily found the bolts that I need, would love to tell everyone what size it is for future reference, but no idea how to measure etc

Its smaller than M14 for SURE though.

Thanks for the help anyway, hopefully this thread helps someone in the future...

[The Dan]

It won't help anyone because you have been given the sizes.

I'm not sure where you are going wrong but life was not meant to be this difficult.

Now, either you are doing something wrong.....or you have an aftermarket turbo or something. The engine is standard and that cannot change. The water feed below exhaust runner 6 is 14 x 1.5.

How about take a photo of what you have and I will tell you what it is

[agentx]

I'll take a pic tomorrow mate - trust me I didn't think this would be that much of a hassle - I went to the wreckers and actually got him to pull out an rb20 block and matched a bolt as well as an rb25 turbo and matched the bolt to that. I might have the turbo bolt size wrong, but the water feed was definately smaller than a 14. I'll post pics in this thread soon to help someone else out ...

I actually have TWO water feeds in the block, the one I'm using now (with the bolt i got) is an inch directly above the one I had blocked. which obviously added to the bloody confusion...

while I've got your attention though, the second issue left is front pipe - everywhere I've looked, rb25 front pipes are supposed to be a direct replacement for rb20's ... I got one from the wreckers, and It doesn't line up the CAT properly etc going again tomorrow to get an rb20 front pipe, any ideas on this?

I've run into that many issues with this turbo swap its not even funny ...

[The Dan]

I'll take a pic tomorrow mate - trust me I didn't think this would be that much of a hassle - I went to the wreckers and actually got him to pull out an rb20 block and matched a bolt as well as an rb25 turbo and matched the bolt to that. I might have the turbo bolt size wrong, but the water feed was definately smaller than a 14. I'll post pics in this thread soon to help someone else out ...

I actually have TWO water feeds in the block, the one I'm using now (with the bolt i got) is an inch directly above the one I had blocked. which obviously added to the bloody confusion...

while I've got your attention though, the second issue left is front pipe - everywhere I've looked, rb25 front pipes are supposed to be a direct replacement for rb20's ... I got one from the wreckers, and It doesn't line up the CAT properly etc going again tomorrow to get an rb20 front pipe, any ideas on this?

I've run into that many issues with this turbo swap its not even funny ...

There is no confusion. The water feed closest to the cylinder head is 14 x 1.5. The one that's an inch below it is actually the factory water drain to completely drain water from the engine. It has a bolt blocking it from factory.

I have 3 RB20 blocks no more than 50 meters from me right now, another 2 at the workshop and at least half a dozen other RB blocks there as well. They are ALL 14 x 1.5 there.

IF you have some kind of freak engine that was a one off build from Nissan and it's smaller than 14, it is going to be 12 x 1.25. Nissan didn't get very creative with bolt sizes

The factory nissan turbo is the same for RB20 and RB25 including the R34 Neo turbo. They all run the same size water feed and return. Are you sure you are looking at the same one? and what happened to the banjo bolts that were attached to the turbo in the first place?

The RB25 dump pipe is a direct swap for the RB20 one as the physical dimensions of the turbo are the same in that regard. The cat may or may not fit because it has possibly been modified at some stage or the rear section has been modified maybe? But it should fit anyway. The cheap ones usually have trouble

[The Dan]

It's also possible the front pipe is wrong. If you are trying to put on a one piece front/dump pipe this may not fit. I haven't tried before but I think the angle is different there. Dump pipe is definitely the same though

although this would suggest otherwise:

http://justjap.com/store/product.php?productid=17316&cat=276&page=1

[agentx]

Yea I figured out i was messing with the wrong bolt half way through the install. I actually didn't notice the other one on top of it (actual feed) due to not going low enough beneath the manifold as it was on the car. I've been through that many banjo bolts that I'm pretty sure you're right and i'm just mixing bolt sizes up.

On the turbo, I realized that I actually needed the oil feed, not the water feed I know - I'm thinking the same thing - I'm an idiot.

So long story short - bolts are sorted (once I get the oil feed one from the wrecker tomorrow and give him back the water feed for the turbo!)

As for your dump pipe advice, it makes sense as the back half of the exhaust till the muffler is bigger (3 inch or something). CAT is definately not modified though since I bought a stock r32 CAT today as mine was stuffed and that also doesn't sit right (sits at a 45 degree angle once connected to the front pipe instead of being flat). What would your advice be for me? Keep the front pipe that I have and the CAT and get a stock CAT back exhaust from the wrecker?

Appreciate your help mate, I'm really in a tough spot for the last 5 days trying to get this up and running.

[agentx]

to answer your question, its a stock dump pipe (came with the rb25 turbo) - and a stock rb25 front pipe - and stock rb20 CAT

actually, here's a pic. the one behind it is the old dodgy front/dump pipe - and a spare CAT

Uploaded with ImageShack.us

Edited November 25, 2011 by agentx

[The Dan]

Ok well the turbo oil feed on both the turbo AND the block are 12 x 1.25

If you have the front pipe bolts tight (3 of them) back them off a little and you will be able to swing it 5 or 10 degrees. The cat on all skylines should have parallel flanges meaning if you stand it on the ground on its 2 bolt flange, the opposing flange should be parallel to the ground. If the cat flanges are not parallel then the cat is wrong. The front pipe should kick in towards the tailshaft right before the end, just like in the picture in that link I provided. If its the stock front pipe then this won't be an issue. I would say it is possible the rear section was modified at some stage and this may be why it doesn't fit.

What exactly are you doing anyway? Are you converting to turbo or just putting on another turbo?

[The Dan]

You should be careful putting that dump pipe across the terminals of a battery

[agentx]

just changing the turbo from a TR43 that blew up - to an rb25 turbo. on a r32 with rb20 (sorry i know i've taken this thread off topic!)