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Rb29 Wow!


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If I were guessing - I would say 20k for the bottom end alone. 50k should do it for a whole engine / turbos etc ..... (providing the rest of your drivetrain is up for it). But I am just guessing....

lets put a bit of reality into this...All respect to Ben and what he has done...just a little food for thought...

i can build one thats very close...with more mid range and top end for 1/2 that price...is a little bit more bottom end under 3500rpm really worth $25K ?. When is a GTR engine driven under 3500rpm ? in traffic ? id say if you want something good in traffic spend the extra $25K you have on a Ford Focus !

Edited by DiRTgarage
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lets put a bit of reality into this...All respect to Ben and what he has done...just a little food for thought...

i can build one thats very close...with more mid range and top end for 1/2 that price...is a little bit more bottom end under 3500rpm really worth $25K ?. When is a GTR engine driven under 3500rpm ? in traffic ? id say if you want something good in traffic spend the extra $25K you have on a Ford Focus !

I was guessing with regard to 50k... it seems better to err on the side of caution if one was planning to build something a little more radical than the well proven 400+ kw RB setups that are out there. For me - understated, quiet, stealthy but with so much grunt is a fair effort.

You are right in saying 25k can buy you a lot of RB Power though - particularly with the right guy spinning the wrenches.

Edited by Antimatter
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lets put a bit of reality into this...All respect to Ben and what he has done...just a little food for thought...

i can build one thats very close...with more mid range and top end for 1/2 that price...is a little bit more bottom end under 3500rpm really worth $25K ?. When is a GTR engine driven under 3500rpm ? in traffic ? id say if you want something good in traffic spend the extra $25K you have on a Ford Focus !

I can see where your coming from Paul, but you really have to see and experience this setup. Comparing dyno graphs with different setups these days may give you a rough indication on how similar/different they are, but out in the real world there are so many different variables. I'd definetly want that low end charge of this setup, the off boost on boost transition is what makes this car phenomenal, everything is all well when you punt a car in a straight line going flat out through the gears, but punt it around a twisty bit of road or race track and this will show how phenomenal this setup is.

Also bear in mind that if you open the bonnet of this car, you wouldn't see much out of the ordinary, quite standard looking. This is setup to be user friendly on the street, with the comfort and fuel economy of a large family sedan and over 700hp on tap.

Back to your question is it worth the 25k for that low end power, DEFINETLY, if you can afford it... :)

What setup are you talking Paul that will have more midrange and top end?? capacity/turbo/boost/fuel/inletmanifold/cams/ecu?? Are we talking similar specs to twoogle??

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He is talking about an RB20 with TD06 . Cant beat it. :)

yep...got it roy in one...hehe

Jack as you can see from the overlayed graphs a few pages back the set-ups are not that different...he has more down low, i power over mid-range and both settle around 460KW at the top end. Both were on pump fuel BP98 and ours was only run in the day before and was on a very conservative tune (quite rich with minimal timing). I put it to you that your car would probably never see below 3500rpm any tracks in Aust. except the one with the big hairpin at the end of the straight. Whats with the fact our car is a straight liner anyway....power is power...torque is torque...who gives a toss what chassis its in or what the car is used for...starting to get sick to death of people using that as a reason to dismiss the engine or cars ability.

Id still like to see a torque graph as requested several times...in a much more realistic scale. Power graphs really dont show the true picture of this engines ability. I can only go off whats been provided at this stage and im sure a better torque graph may force me to eat my words...

My post was not made to offend anyone, as Ben is aware im sure at the respect i have for him and his work. He is the leader in this country in many areas of development of Nissans/Skylines. Just looking at the whole setup from a different angle thats all. :)

Edited by DiRTgarage
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This is the usual smaller capacity versus larger capacity argument that occurs with any engine combination. The difference here is that the larger capacity engine doesn't weigh a meaningful amount more than the smaller capacity engine, so the advantage is always with the larger capacity engine. Since BHP is simply torque x rpm / 5250, at any given rpm (all things being equal) the larger capacity engine will always generate more torque and hence more horsepower. The otherside is the larger capacity engine will make the same horsepower at lower rpm, which results in lower mainteneance costs and frequently a less costly build.

Cheers

Gary

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This is the usual smaller capacity versus larger capacity argument that occurs with any engine combination. The difference here is that the larger capacity engine doesn't weigh a meaningful amount more than the smaller capacity engine, so the advantage is always with the larger capacity engine. Since BHP is simply torque x rpm / 5250, at any given rpm (all things being equal) the larger capacity engine will always generate more torque and hence more horsepower. The otherside is the larger capacity engine will make the same horsepower at lower rpm, which results in lower mainteneance costs and frequently a less costly build.

Cheers

Gary

are you taking into account the differing rod loads and hence wear with a longer stroke engine?

obviously not.

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are you taking into account the differing rod loads and hence wear with a longer stroke engine?

obviously not.

The RB30 rod stroke ratio is higher (numerically) than the RB26 rod stroke ratio, so the side load wear (bore and piston) is demonstrably less. Hence the parasitic losses are lower so the engine produces more torque for the same combustion pressure. In addition the superior rod stroke ratio (which is close to what many engineers consider the ideal of 1.75 to 1) in itself results is superior transfer of power to the crankshaft as the rod angle during combustion is less.

There is a valid argument about the piston speed being higher in an RB30, but these days the piston ring quality overrules most of that objection.

This inferior rod stroke ratio is one of my objections to the RB29 concept, as it is with the OS Giken RB30.

Cheers

Gary

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The RB30 rod stroke ratio is higher (numerically) than the RB26 rod stroke ratio, so the side load wear (bore and piston) is demonstrably less. Hence the parasitic losses are lower so the engine produces more torque for the same combustion pressure. In addition the superior rod stroke ratio (which is close to what many engineers consider the ideal of 1.75 to 1) in itself results is superior transfer of power to the crankshaft as the rod angle during combustion is less.

There is a valid argument about the piston speed being higher in an RB30, but these days the piston ring quality overrules most of that objection.

This inferior rod stroke ratio is one of my objections to the RB29 concept, as it is with the OS Giken RB30.

Cheers

Gary

i think the only person you are kidding is yourself...put the textbooks away Gary and think about it.

MORE TORQUE IS MORE STRAIN/WEAR ON COMPONENTS...end of story.

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i think the only person you are kidding is yourself...put the textbooks away Gary and think about it.

MORE TORQUE IS MORE STRAIN/WEAR ON COMPONENTS...end of story.

Based on that sort of thinking then an RB20 is better :( As long as components are rated for the torque then whats the problem. Diffs and gearboxes are easy fixes, so you have suspension picks ups and driveshafts etc. They are typical Datsun tuff in Skylines so not like Commodires etc that when they grab some mroe power then have been known to damage suspension arms/pick ups, Hondas with their troublesome driveshafts etc etc

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i was just pointing out Gary's arguement that a higher revving engine with less torque wears more than higher capacity one with more torque...what a load of dribble.

the difference in wear rates between the two would be almost negligible for a given power output, as more revs would even up the ledger with the higher wearing torque engine.

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It will be interesting to see how Spoolups RB30 3.4ltr stroker kits perform in comparison. Both price and performance.

as above, more info on this. very keen to know bore and stroke, aswell as rod/stroke ratio (seems to be a hot topic in this thread :P )

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Jack as you can see from the overlayed graphs a few pages back the set-ups are not that different...he has more down low, i power over mid-range and both settle around 460KW at the top end. Both were on pump fuel BP98 and ours was only run in the day before and was on a very conservative tune (quite rich with minimal timing). I put it to you that your car would probably never see below 3500rpm any tracks in Aust. except the one with the big hairpin at the end of the straight. Whats with the fact our car is a straight liner anyway....power is power...torque is torque...who gives a toss what chassis its in or what the car is used for...starting to get sick to death of people using that as a reason to dismiss the engine or cars ability.

WOOOOW, easy tiger!!!! :P

What Im trying to get at is that the low end punch of the setup has a large effect on boost transition, something that your car does no need. Getting on and off and then back on the throttle surely can be benefited by the low end response (sub 3500rpm) the car has, correct me if I'm wrong as I'm definetly no expert.

So basically because your car is designed to do 9 sec pass you would not need the same effect. Definetly not bagging twoogle as I'm sure with some tweaks it can be a track weapon. And If i won tattslotto it would make a nice addition to my dream GT-R collection.

So I guess getting back to your question is it worth it? Probably not for what you want the car to achieve....

Do I make any sense?? Probably not.... :)

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Two different schools of thought, most interesting.

Considering where I want to take my engine, built 26, 2.8 stroker, 26/30 combo, off the wall VH41de+tt combo...

so threads like this are quite useful, as heated arguments are where the juicy info comes out :)

Edited by infamous_t
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he might as well....every other un-registered trader on this forum is advertising in this thread.

unless this all settles down it will be closed.

Jack...you make all the sense in the world. Its not set up as a drag engine though...its got more low-down torque than most street/circuit cars. If it was a drag engine it would be wearing high mounts.

If i won Tatts id set it up with a big brake kit, see Ben for some good suspension and cut loose on the twisties. Finally putting the issue to bed. :)

Dunc's its gone to PM...its time some home truths were told

Edited by DiRTgarage
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are you after a torque graph?

the first post has torque

look at the scale

0-27000N doesnt show a lot

a scale 3 times smaller on the same grid would be better i.e. 0-9000

some say a Croydon AFR scale is bad.

Edited by DiRTgarage
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