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Hybrid Rb's

TTT

By TTT,
in Engines & Forced Induction

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TTT Grand Master

TTT

Posted
Posted

RB30/25 or 30/26 seem to be the flavour of the month due to making such good results with small outlay (in some cases), So I've been thinking what else is possible.

and how are they done?

what sort of dollars?

rb24 is made using what?

is the rb20 head usefull on anything other than the rb20 bottom end?

what else, if anyhting, can the rb26 bottom end be used for?

can an RB25 head be bolted to an rb26 bottom end? what would be the end result (obvisouly not as good as the rb26, but would it be better than a stock rb25?)

what happens if an RB25 bottom end is put undre an RB26 head?

can the rb20 bottom end be used with any other head and what would the outcome be?

I'd usually PM this sort of crazy questions to SK, but he probably gets annoyed with all my dumb ideas :happy:

so now you can all be part of it..

:D

cheers

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Jago Mentor

Jago

Posted
Posted
tommy kaira made the m30, a rb30de which used an rb20de red top head and rb30e bottom end. the result was 230hp which was put into quite a few r31's that they made

christ that must breathe like crap

i'd also be keen to see/know if a 25 or 26 head can go on a 20 block

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Beer Baron Grand Master

Beer Baron

Posted
Posted

GTST who cares is a RB25 head fits on an RB26 block? it would be a waste of time.

same thing goes the other way around.

also only good combo from an RB20 is RB20. or the RB22, 23 24 ideas, but both still use RB20 head and RB20 block.

RB26 head on RB26 block is the best one i reckon, but certainly RB25 and RB26 heads on RB30 blocks have their merits.

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ellie Proficient

ellie

Posted
Posted (edited)

Has anyone on here actually experienced any of these motor combos on the road? Are they a worth while venture (more torque, better top end etc.)? I ask because I actually have a lot of what is required to build one if my motor goes pop and was keen to hear some real world, seat of your pants driving experiences (street and track). SK, you seem to have built a few. What was your initial impression of a well set up and tuned combo and which do you think would be the best for 90% street, 10% track

Cheers in advance :D

Edited by ellie
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grigor Rising Star

grigor

Posted
Posted

I think you'd have to have time and money to burn for some of these combinations, but my favourite is a chopped Rb30 block with an Rb20 crank, Rb30 rods & pistons, and Rb25 head.

Would be a bit under 2.5litre and with those long rods should have great combustion properties as well as revving like crazy.

But stacked against all that work, the Rb30det looks the go.

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ellie Proficient

ellie

Posted
Posted

I think going to the 2.5L capacity sounds most appealing using an Rb25 turbo bottom end with an R32 RB25 N/A head. allowing all your Rb20 auxiallaries to be reused with a remaped standard computer! Giving you the extra capacity with out the much larger outlay of a full RB25 swap.

My 2c anyways :D

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