I'm not an expert on this but..

[rubbersidedown]

I'm not an expert on cars or anything but doesn't it seem like that a 6 cyclinder should be more than 2liters? I'm refering to the skyline rb20det. normally when i see a 6cyl its at least about 3.4liters. so i guess my question is. why only 2liters in a 6 cylinder engine?

[BlankFlip]

just look at nissans skyline gt-r, those things r fast as ####, n they r only 2.6 l (rb26dett). i don't want to say nething about a 6 bein' only a 2.0 cuz i'm sure somebody in here will give u an exact answer of why this is so.

[S13Grl]

It most definitely has to do with the compression chamber (size) and the compression itself. So... it's a fast f'n turbo, it better be smaller!!! :biggrin:

there are even 1.8 liter v-6's in existence, like Mazda Mx-3's had in there &quot;sport model&quot; <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=':p'>

[BlankFlip]

then there r like 3.8 l v6 mustangs that r basically all motor. does it mean it could beat a skyline gt-r, #### no!

[ca18guy]

I'll add to what everyone said and say that they might also have made it that small for tax/emmission's reason's in Japan. alot of countrie's give you tax breaks for having a smaller displacement engine, Nissan probably would have made it a 4 cylinder but it would have cost them too much to retool there machine's to make a 4 cylinder RB motor. Just a idea as to why it's so small though.

[S13Grl]

I'm still sticking to my combustion chamber size idea.

[S13Grl]

I'm still sticking to my combustion chamber size idea.

[HippoSleek]

I've got $5 on ca18guy's tax theory. &nbsp;In Japan, you have to pay a tax based on the displacement of your engine. &nbsp;Hence micro cars with 1.1L engines, high output 4's, and liberal use of turbos. &nbsp;As a result, the old Skyline was not such a beast - so they kept the tax lower (it goes up a LOT after 2.0L). &nbsp;

As far as efficiency, many V engines are smaller than you may think (due to a whole bunch of technical stuff about rotational mass and chamber size). &nbsp;Bottom line - smaller chambers allow higher revs and more power for the same displacement. &nbsp;Examples: &nbsp;
Lambo Diablo - Engine Type..... .....V12
Engine Displacement..... .....5707 cc.
Horsepower..... .....530 bhp @ 7100 rpm
Torque..... .....428 ft-lb. @ 5900 rpm

Lucky Strike Bar Honda 003 - &nbsp;Honda RA001E V10, 3-litre displacement
Max revs In excess of 17,000 rpm
... don't you wish they published the hp figures!

[vancouvers14]

it is a tax issue. &nbsp;every company in japan makes a 660cc engine, cause thats another tax level. &nbsp;Probably 1/3 of all cars in japan have a 660. &nbsp;And low-displacement v6s are very common in japan.

[S13Grl]

I honestly never doubted CA18Guy's theory, I just figured that the size of the combustion chamber and the displacement itself definitely helps the performance output. And I totally believe the tax and all that other stuff...

[Chokudori]

Does it have anything to do with the RB being inline-6 rather than V-6? wouldn't a 3.6L inline-6 end up being really long?