RB30 engine conversion (lots of pics)

[R32 Combat]

If you could find what I'm supposed to use, that would be super.

[toddrb30gtr]

Originally Posted by R32 Combat

If you could find what I'm supposed to use, that would be super.

had a good look on the net for ya but couldnt find anything the same over here in uk......... if you take the time and clean the block, gasket and head
up, you could seal around each water/oil gallery using loctite 574 flange sealer ( being very careful not to put too much on so it doesnt go where it shouldnt ) that would work better than the spray!!!!

[R32 Combat]

Nimbus motorsprot sell aerosol Hylomar. I'm going to speak to them and see what the advise.

I used loctite 5699 flange sealer. I think what I might do is, with a syringe, apply a bead both sides of the gasket around the various holes and let it cure over night before assy.

Something else that occured to me is the amount of head distortion allowed is much less with a copper gasket than with a multi-layered gasket. I think getting the head skimmed will help this.

[SteveN]

Originally Posted by R32 Combat

SteveN, the 'O' rings are steel, make from welding wire.

AAah, sorry, I was being thick due to different trerminology to what I use!

Yeah, a wire ringed will be FINE with a normal head gasket, infact should be more effective than with a copper HG!

What I was talking about was Coopers Rings, which are seperate firing rings machined in to the block, much more complex, and a complete pain.

Ive had wire ringed blocks on a few cars, always worked well.

[R32 Combat]

Well, after a long and interesting call to Nimbus motorsport, the conclusion is......

Don't use a copper gasket unless there is no other option. Use a Cometic with the 'O' ringed block and all will be fine. Copper is just too much of a pain in the ar$e..

[R32 Combat]

After a long and interesting chat with a guy who runs an engine service machine shop, I've decided to fit a STD head gasket with the 'O' rings still in the block. I can't use a multi-layered gasket and I can't get the bloody 'O' rings out of the block so I don't really have much choice.

[Chris Wilson]

I have built loads of engines with wire O rings in the block that bite into composite head gaskets just outside of the fire ring of the gasket. The localised compression of the gasket is a great way to run very high cylinder pressures with a stock gasket. I agree, copper gaskets went out after WW1, and have no place as a head gasket on a modern engine.

Until I got a milling machine I used a hand tool from Iskenderian in the US to put the O ring grooves in blocks. In typical US style it was called the Iskenderian Groov-Matic tool, I think they are still available from here:

http://www.iskycams.com/glossary.php



O ringing of blocks is still a very good way of running cheap head gaskets on turbo engines.

I have never seen an RB2* engine acually have head gasket troubles witha stock gasket, even at high boost, unless somehing else was amiss. I often wonder where this "need" for multi layer shim gaskets from expensive sources originated from...

[paul cawson]

I Have reused my Tomei head gasket 3 times on two different bottom ends and it still seals well.

[R32 Combat]

I've got my head back now and hopefully I'll get to the stage of working out what shim thinknesses I need tomorrow. Maybe I can use all the shims I have, that would work out well but it's never that simple..

[R32 Combat]

Well, after much head scratching, I've finally found the problem with my car.

Basically, after getting the head skimmed and inline bored, the car wouldn't idle and wouldn't draw a vaccum on idle yet it drove ok.

The problem was with the cam timing, I advanced the exhaust cam 7degs and it works again.

This is because the the cams are lower in relation to the crank shaft so you can't use the timing marks anymore.. It goes to show how critical it can be.

It only took 2 days to work out but now its obvious.

[Scooby]

Hi Andy;

Nice detective work. I guess that means the timing has got to be set up manually whenever changing the belt?

Cheers

[R32 Combat]

As I use adjustable cam pulleys, where that are set now 'should' be the correct position in future. But just for reference, I've photographed the settings..


Now the engine has good oil in it, we started doing some boost mapping yesterday evening. Running only .8bar and 6000rpm. I've very impressed with the way to performs, it pulls strongly from 3000rpm. Boost come in very well concidering the size of the turbo. From 4000rpm in 2nd gear the boost is @ .5bar using only 1/2 throttle. I think there is a bit more to come yet too.

At least more I can start reaping the rewards for all my hard work and get out and enjoy the car now.

I think its going to be a flyer when its running full boost and 7000rpm..

[tyndago]

Originally Posted by Chris Wilson

I have never seen an RB2* engine acually have head gasket troubles witha stock gasket, even at high boost, unless somehing else was amiss. I often wonder where this "need" for multi layer shim gaskets from expensive sources originated from...

I have seen a lifted head gasket on an RB26. 2+bar on 2530's, with direct port nitrous. Perhaps though something else was amiss. I chunked a piston on #6,but it lifted the head around #4.

Right around #4 there is an issue, like the block winds up a bit different than the head. Might be that two different metals thing.

Talking to Mr. Tamura, he says circuit use above 450 hp to use a metal headgasket. Another issue, that may be the real issue is the head washers cracking.

[R32 Combat]

Just for reference, an OEM head gasket and an 'O' ringed block seems to work, which is nice. The car doesn't get through water or oil and on its 1st long run @ 70mph it returned 24mpg. Gentle around town driving returns 22mpg.

Things are looking good..

[Luffy]

Well Done Andy glad its worked out for you mate, hope theres no more hidden surprises!!!