Jump to content
SAU Community

Ohmagoshbang!

Moanie

By Moanie,
in New South Wales

 Share

Recommended Posts

  • Replies 240
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

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?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Latest Posts

    • Kinkstaah
      R34 Handbrake light saying ON and intermittently flashing

      By Kinkstaah · Posted

      This. The R34 handbrake icon DOES come up when the brake fluid level is low. You might be sitting right on that threshhold. I have been down this diagnosis path and this was the solution (and it was pretty much as full as your picture is to begin with).
    • Duncan
      R34 Handbrake light saying ON and intermittently flashing

      By Duncan · Posted

      Unfortunately the cavaet to that is that while any scan tool should be able to read the code, the workshop will need a consult plug to OBD socket adapter. You don't have a location on your profile, where are you based?
    • Kinkstaah
      RB25DE NEO with Haltech ECU

      By Kinkstaah · Posted

      @Haggerty this is your red flag. In MAP based ECU's the Manifold pressure X RPM calculation is how the engine knows it is actually...running/going through ANY load. You are confusing the term 'base map' with your base VE/Fuel table. When most people say 'base map' they mean the stock entire tune shipped with the ECU, hopefully aimed at a specific car/setup to use as a base for beginning to tune your specific car. Haltech has a lot of documentation (or at least they used to, I expect it to be better now). Read it voraciously.
    • GTSBoy
      RB25DE NEO with Haltech ECU

      By GTSBoy · Posted

      I saw you mention this earlier and it raised a red flag, but I couldn't believe it was real. Yes, the vacuum signal should vary. It is the one and only load signal from the engine to the ECU, and it MUST vary. It is either not connected or is badly f**ked up in some way.
    • Murray_Calavera
      RB25DE NEO with Haltech ECU

      By Murray_Calavera · Posted

      @Haggerty you still haven't answered my question.  Many things you are saying do not make sense for someone who can tune, yet I would not expect someone who cannot tune to be playing with the things in the ECU that you are.  This process would be a lot quicker to figure out if we can remove user error from the equation. 
×
×
  • Create New...