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Rb20 Red Top, Mods?

frenchy89

By frenchy89,
in Engines & Forced Induction

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frenchy89 Community Regular

frenchy89

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Gday guys,

I've just bought a RB20 Red Top to rebuild (brand new block and head!). I also have a reco'd silver top bare head, am i able to put the silver top head onto the red top block (are they the same, would it be worth it?) ? Also i dont want to use the original NICS Inlet system, what would you guys reccommend manifold/intake system wise? Wanting to run a bov and cooler.. Any help would be much appreciated, this is my first turbo motor so should be a bit of fun!

Cheers,

Rhys

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R31Nismoid Grand Master

R31Nismoid

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Red top and Silver top heads are not interchangeable.

Your better off using the Silver Top as the Red Tops have FAR too many electrical issues with sensors and stuff.

So get a silver top bottom end/loom aswell. And use that. It will save you money in the long run.

frenchy89 Community Regular

frenchy89

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What sort of problems? I'm going to be running a microtech setup. How does the red top and silver top cylinder head differ? Will after market manifold's fit up to the red top? Any help much appreciated. I can't justify going and buying another block and cylinder head as the one i have are brand new

floody Experienced

floody

Posted
Posted
yea apparently the oil galleries are different, but no one actually states why the silvertop head wont work on the redtop block

Well that would be why.

If you are sticking with the redtop, a redtop ECCS six port manifold will fit; however this does mean you'll still have the 12 port butterfly plate as they both run it. Also the NICS has the injector bosses in the head casting, ECCS has them in the manifold, so you'd have to blank those injector bosses.

Aftermarket RB20/25 exhaust manifolds will fit, intake no.

Rumour has it the redtop blocks are stronger, but yet to see proof of that. I guess with the butterflies out, sandwich plate ported and the ECCS manifold in a redtop should flow as much or even more air than the silvertop head.

All the crap to run a redtop is ancient and somewhat unreliable, you'd really need to adapt silvertop sensors and stuff to make it a bit more reliable.

It seems like a lot of farking round for a stock motor build; unless you're going to piece together an animal 20 or an RB24 I'd probably just slot in a complete silvertop and save the pain.

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