Rb20det Intake Manifold Conundrum

[Wheezy]

Hi all,

I currently have a KU engineering FF Plenum on my RB20 and am fairly happy with its the job it is doing, however it is a cut and shut factory manifold.

The trouble I am having is that there is a crack on the #6 runner that is moving towards the injector hole on the manifold (factory part of the runners).

I could TIG weld it however the direction of the crack concerns me.

I have been thinking about getting a Greddy RB25 manifold (Genuine greddy) and adapting it. With Q45 TB to suit.

I do not run IAC or AAC so there is no issue there, and I have an aftermarket fuel rail (Which I am lead to believe will still work with my SARD injectors on the greddy manifold).

I also DO NOT run heater lines etc under the manifold and my turbo is a Trust oil cooled only unit which takes out a level of complexity.

The other option is a stock R32 GTR manifold and ITB's. The car runs a RB26 R33 D-Jetro ECU therefore I have the GTR air temp sensor already installed.

Can anyone confirm that the Greddy option has been done on an RB20? I have seen RB26 done, howerver I was hoping that by chance the RB25 manifold will somewhat bolt upto the RB20 (silvertop) without the use of a spacer plate?

If that is not the case I will have to have a billet adapter made.

But if the Greddy unit is an easier option I will probably go this route instead of the RB26 unit.

Here is a pic of my current setup.

-Ignore the Z32 \ Grex Filter that is now long gone

Thanks in advance

-Jez

[jeffworld2]

I have RIPS plenum here i dont need if anyone is interested

[GT-RZ]

weld the crack up. if your worried about the crack reopening in the same direction drill a small hole either end of the crack and then weld it all up.

see if it holds up, id be doing that before buying a new manifold?

[The Dan]

weld the crack up. if your worried about the crack reopening in the same direction drill a small hole either end of the crack and then weld it all up.

see if it holds up, id be doing that before buying a new manifold?

+1 on that.

Definitely weld it up. Why did it crack in the first place? and are you certain it's a crack and not just a casting mark?

[Wheezy]

The air leak tells me its a crack. I believe that its due to an issues with the casting.

[GT-RZ]

Oh wait i think i see the problem!!!! you need an excuse to buy a new fancy perfect manifold...

Yep it's F*cked if you leave it the crack will enlarge and cause your left tire to explode. Very dangerous, i would suggest a custom jobby. that RIPS one sounds nice?

[Roy]

Well i have a Plazmaman manifold laying at my place. My car is still at the panel shop and i am still working in India. So if you want to trial it on your car to see if its better then what you already have. Either buy your own or just buy one and replace mine. We can come to some arrangement.

Personally, i think that multi throttles are the way to go but the GTR ID is too big which means $$$$ to get smaller throttle bodies

[89CAL]

so using the stock runners from the standard intake plenum? Buy the stock intake manifold or just the runners and use that?

[acsplit]

got pics of the crack closeup?

[Wheezy]

Oh wait i think i see the problem!!!! you need an excuse to buy a new fancy perfect manifold...

Yep it's F*cked if you leave it the crack will enlarge and cause your left tire to explode. Very dangerous, i would suggest a custom jobby. that RIPS one sounds nice?

....If I wanted to be patronised I wold have asked.

Think about it for a second, crack moving towards the injector hole, I can try to stop it from growing but if that fails, and one day out of no where fuel starts pissing out all over the place, well Im sure you have seen what can happen.

However, you are partially correct, now is the perfect time to spend some cash on a part which I think could cause me some serious grief down the track, and why not spend the cash on something as exciting as a GTR multi throttle setup.

Not all Skyline owners are povo's who work at their cousins *insert random takeawawy shop* to pay for fuel to rip up the princes highway on a friday night.

Now please show yourself the door to my thead.

Roy, are they the ones that use the stock bottom half of the runners and replace the top half (literally a bolt on)? I am not so sure I want to go that direction, however if I cant fix what I have now, I might get back to you and see what we can sort out for the interium. Cheers!!!

AC, Im taking the manifold off today to take to be looked at by someone who can potentially fix it

If I can get the crack sorted some time this week I will probably take the car down to my tuners for another touch up and talk options then, I was just hoping someone with past experience would pick up this thread and spark some ideas.

[murrayis]

Wheezy,

What has Jack From Ku Engineering said about this?

I had a crack in my first one and he shipped out the replacemenet within a day or 2. There new rb20 manifolds replace the entire item.

[Wheezy]

The crack appeared a while ago and I thought it was just a casting mark, it has since grown. The part that failed was the factory part of the intake. I have had the intake for nearly 2 years now, pretty sure it would be out of warranty anyway.

CBF getting a replacement when I can:

1. Weld it

2. upgrade

[Roy]

What ECU are you using now? Link?

[Wheezy]

Power FC D-Jetro from R33 GTR

[Wheezy]

Got put onto this thread: http://forums.nicoclub.com/zerothread/307325

However, there is nothing solid in there, no dyno comparisons or anything really solid to go on.

Might be worth some back to back testing to see if RB26 is worthwhile, expensive exercise, but Im used to being a guinea pig.

[Wheezy]

I have RIPS plenum here i dont need if anyone is interested

I keep hearing about these but I have never seen one, got any pics?

[GT-RZ]

I was simply making a light hearted joke, you were supposed to laugh!

Really the answer is obvious, you are not asking for information how to fix it because you did not post up any image of the crack.

what can you expect? I told you how you should weld it up to prevent cracking in the same direction.

You will notice the factory runners are cast and quite thick so i would advise you remove a small amount of material around the crack with a sharp tipped die grinder. then get a competent welder to fill er up, then drill two holes either end of the weld and weld them up.

There is the full story. I told you basically that before the rest was obvious.

If you did not want advice on fixing it then i suggest you should have called the topic 'New manifold options for RB20'.

My posts were for your benefit only.

Edited July 6, 2009 by GT-RZ

[Wheezy]

Cheers ears.

I have given it to a professional to take care of. Should have it back tomorrow.

I was always going to fix it, but the conundrum is if I should invest in a better setup in the long term.

This was also inspirational...

[GT-RZ]

Bit of work but looks the goods.

[Reecewashi]

Cheers ears.

I have given it to a professional to take care of. Should have it back tomorrow.

I was always going to fix it, but the conundrum is if I should invest in a better setup in the long term.

This was also inspirational...

this is a beautifullllllll set up i will also try it on my rb20, i was thinking of the conversion for some time now