R33 Rb30 Conversion

[nugget400hp]

gday guys. im currently building an rb26/30 for my vl turbo, i will be using an autronic and a 1000hp ta45 turbo.

Just wondering which pistons to use? If I buy CP forgies that come in 9.1 comp ratio it should drop to the perfect

comp ratio once the head is on yeah?

also, do i need to run the oil squirters?

thanks

brad

[shanef]

cp pistons with total seal gapless rings, and no need for squirters just coat the skirts & crowns

[nugget400hp]

thanks mate, quick answer

cheers again, ill throw pics up when shes finished

[Al]

Fair enough, i stand corrected

Just assumed a 20yr+ old motor would be more prone to failure, especially when almost every VL in the country has been flogged to death .

[Cubes]

And with the SOHC head no doubt overheated a few times when they crack every 150,000km's.

[shanef]

Fair enough, i stand corrected

Just assumed a 20yr+ old motor would be more prone to failure, especially when almost every VL in the country has been flogged to death .

i've heard stories that the old school v8 boys looked for 300,000km+ blocks for thier mega hp builds, and wouldnt use fresh, new blocks, because the old ones have been well seasond and the like, dunno how true that is though

[Rolls]

And with the SOHC head no doubt overheated a few times when they crack every 150,000km's.

Thats why you use a block from a 31, they didn't suffer the overheating problems the VL had.

[r33_racer]

I thought that was due to holden putting an inefficient and undersized radiator in the vl...while nissan actually knew what they were doing...hence why vls have overheating problems and the r31 didnt....is that true?...i actually heard that from several holden nuts!

[Spoolup]

I thought it was due to the fact that the VL radiator sat lower than the top of the head where as the R31 didnt ?

[paulr33]

yeah its from the radiator sitting lower in the vl

[r33_racer]

yes sorry...my memory is crap...thats what it was. the radiator sitting lower. Didnt mean to misinform....my bad.

[Cubes]

R31's still cracked the sohc heads. BUT it was less common as their cooling system was just that little bit better.

Just a design flaw of the SOHC head.

Overheat our DOHC heads and its very rare to crack one.

[Adriano]

It was also due to the rwin bypass system on the vl, and a manufaucturing flaw on the baffle in the radiator, which meant over time it broke off, fell down and blocked the lower radiator hose.

[shanef]

R31's still cracked the sohc heads. BUT it was less common as their cooling system was just that little bit better.

Just a design flaw of the SOHC head.

Overheat our DOHC heads and its very rare to crack one.

nah, they just become pourus and bend...

[Spoolup]

and lose their hardness

[Al]

I thought it was due to the fact that the VL radiator sat lower than the top of the head where as the R31 didnt ?

This leads me to my next question:

As the head is sitting an inch higher, is this going to cause problems; just like the radiator issue in the VL?

Do i need one of those custom remote radiator fluid reservoirs, thats mounted higher in the engine bay?

[Cubes]

Don't loose sleep over it. The head sitting higher than the radiator isn't a problem providing its bled correctly + I don't believe its anywhere near sitting higher than the radiator, those big rocker covers pump it all up to make it look like it sits higher.

The SOHC head cracking is simply poor head design.

If the SOHC gets a little too warm the heads crack.

R31's have a better alum. radiator that keeps things cooler, a better more open front end that allows more air to the radiator.

VL's biggest and most common problem these days is the radiator's baffle design that rusts allowing water to bypass the core; as a result they get warm and crack. Then there's also the failed viscous fan that fails; temperature creeps up and bang cracked head. Of which also applies to the R31's. I've seen a few also have blocked coolant passages in both the block and head/plenum/inlet. All of which are age/lack of maint. related.

Do a little google..

http://www.google.com.au/search?hl=en&...acked&meta=

Fear not, its just the crapo sohc head design; aus market... chances are it was a rushed job, why sink the development $$ in to a market that is so small.

[Scooby]

bonnet shuts.

engine goes.

flatbed tomorrow morning over to exh shop for new y pipe, then onto dyno to check timing and mixtures etc.

giddyup.

[r33_racer]

awesome...........anxious. No sleep for you then hey?

[Scooby]

yeah it was a pretty restless night. couldn't believe how quickly it caught, ran and idled smoothly - pretty much straight way, with instant pressure. at least if it's a dog on the dyno I can turn it into a giant water pump and use the RB26 to run it. just got to concentrate on the niggly things that are bound to arise. last night was filling it with coolant, then heard it hitting the floor - thinks oh fark what's that - and it was the banjo that goes into the block - about .5 of a thread too long and the washer didn't seal. running long dumps so getting it out was a bugger, but an hour later and with some judicious application with a hacksaw no more leaks.