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Moanie

By Moanie,
in New South Wales

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DoughBoy Veteran

DoughBoy

Posted
Posted
Sif.

Bring it, Bish.

I stand by what I said.

Heh will submit my essay later after work. Base physics seem to be overlooked, so will have to include a chapter on that and basic mechanics as well.

Oh and if it was only oil surge/spun bearing, why does piston 5 have alot of detonation peppering?

BU5TER Grand Master

BU5TER

Posted
Posted
Sif.

Bring it, Bish.

I stand by what I said.

3L bottom ends help ONLY with low end torque/tractability (good for general street use, yes)

BUT

The shorter stroke RB26 based engines are ALWAYS a better idea as out-and-out race engines, for all the reasons I mentioned and more.

Need I remind you that the 3 fastest drag GT-Rs on the planet use 2.8L or smaller engines, with the HKS 33 using their own 2.8L kit (crank has 4mm more stroke than normal [77.7mm])

But I'm sure in your mind the 3/3.1L jobbies are better, right?

Your a gimp, for those of us that don't own a multi million dollar company ie HKS and build a car from our own catalogue and aren't trying to be one of the 3 fastest GTR's on the planet tell my why a 3L isn't a good way to go for a RWD car for someone unlike yourself that has some description of a budget?

oh and with all this knowledge you posses what have you built or done with your car?

shif_tea Grand Master

shif_tea

Posted
Posted
Your a gimp, for those of us that don't own a multi million dollar company ie HKS and build a car from our own catalogue and aren't trying to be one of the 3 fastest GTR's on the planet tell my why a 3L isn't a good way to go for a RWD car for someone unlike yourself that has some description of a budget?

oh and with all this knowledge you posess what have you built or done with your car?

tehehehe he said gimp :sick:

sh@un Grand Master

sh@un

Posted
Posted

*sigh*

Heh will submit my essay later after work. Base physics seem to be overlooked, so will have to include a chapter on that and basic mechanics as well.
Your a gimp, for those of us that don't own a multi million dollar company ie HKS and build a car from our own catalogue and aren't trying to be one of the 3 fastest GTR's on the planet tell my why a 3L isn't a good way to go for a RWD car for someone unlike yourself that has some description of a budget?

oh and with all this knowledge you posses what have you built or done with your car?

Oh dear...Seems I've offended the 'RB30 bottom end' crew.

Gimp suit in the wash at the mo'. It's just regular old Shaun for today *LOL*

Look,I'm sure an 3-3.1L RB with a twin-cam head can make lots of power and is great fun, and I know it CAN work very well (Wilall racing as an example, especially [yes, yes- that's an OS Giken kit]), and I didn't mean to step on the toes of anyone that's gone to the trouble of doing the conversion themselves.

But I just don't think that using the 85mm stroke crank from an RB30 is the best idea for engine longevity/reliability at high engine speeds.

But it's all relative.

To be at the pointy end of 1/4 mile competition, you would be rebuilding/pulling down the engine on a fairly regular basis (in comparison to a mildly hotted up performance engine, anyway) to make sure everything was still o.k

Like I mentioned in my original post

'ALL THINGS BEING EQUAL'- i.e rod/piston strength & weight, the shorter stroke engine will be able to rev higher, before mechanical limits come into play, due to the lower piston speed.

More revs = more combustion cycles per unit time = more torque = more power (if the motor is designed/blueprinted for it)

Yes, the 3L has more capacity (approx 66cc per chamber, wow), but, within this engine design, IMHO it's not as important as the rev limit of the motor with regards to how easily it makes big (v.big) power.

Hope this clears things up

p.s Wil- no more taking my posts out of Whoretown :sick:

2rismo Grand Master

2rismo

Posted
Posted

So am I'm missing something? Mona shouldn't go RB30 bottom end because she'll need to rev it to 15krpm?

Some of the VL guys down south ROUTINELY rev their VL RB30 combos past 9krpm - one sees 11krpm from time to time.

In other words - I don't see your point.

DoughBoy Veteran

DoughBoy

Posted
Posted

Dude with every post there are more misconceptions brought into the equation. You start off talking about a street motor on pump fuel, then jump to quickest GTRs in the world, then back again to street motors and longevity, and then talk about theory and limits.

Throughout all of this you've thrown in misleading statements, outrageous and unverified claims, and total bullshit.

I only get my back up over misleading information, if you want to go ahead and talk up RB26 combinations go for it - I really don't care. But other people can and will get the wrong idea over misinformation, which isn't a good thing.

sh@un Grand Master

sh@un

Posted
Posted

For anyone who still cares:

Nissan had the RB30 design from the mid 80's

The RB26 came out in the late 80's

They could have used the 3L engine in their soon to be all-conquering 'group A homologation' race special (ie R32 GT-R)

Can anyone give me a coherent, logical reason why they chose to design an engine with 2568cc capacity rather than just use a twincam head on a balanced and strengthened version of an engine they already had- that was 2962cc?

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