[JrZook]

tanshi wrote:

i agree dan, but that sorta power and the way it would pick up through those revs, isnt it going to be really hard to control in a zook which is what were are talking about

That is determined by the linearity of the power curve and the flatness of the torque curve.

It does not seem peaky at all, looks like nice roll on power to me.

[royce]

how do you put along in a shopping center car park? put it in lowrange?

[JrZook]

royce wrote:

how do you put along in a shopping center car park? put it in lowrange?

Fair point. Idle speed is ~1250rpm for them.

What speed does a stock WT sierra with 31's and no gearing idling at 850-900rpm in 2H 1st compare to an engine idling at 1250 with say the 6.5's reduction in 2H and the same size tires for argument sake?

[=wardy=]

seank wrote:

busa powered samurai
www.youtube.com/watch?v=JrHSbFIHioo

that thing is cool

[tanshi]

=wardy= wrote:

seank wrote:

busa powered samurai
www.youtube.com/watch?v=JrHSbFIHioo

that thing is cool

didnt look like it worked all that well to me.

[got_bar_work]

U could run it to a vit auto then Sierra case with 6.5 And some 5.12 diffs
That would be more then enough gearing for anything
Just use the dog box as range changes on the fly with out using the cluch

[shep]

i reckon a ST1100 motor would be a better option. already has a tailshaft
and lots of real power off idle plus the motor looks nice.

[sideways]

JrZook wrote:

Ben_Sierra what the hell do you base your assumptions on?? The internet?

Going from the dynochart that sideways posted up, busa engine absolutely pisses all over a G13a/ba in torque everywhere in its rev range!!

^^^

It's just like the rotary engine thread again.

And Royce, if you had the skills and money to put one of these in a zook then I'm sure you'd have the sense and resources to gear it appropriately.

[jonno_racing]

i also think a dog box on a lever would be amazing... those times on a hill climb u need to grab the next gear and mash the throttle or back a gear.. same deal...
i love the idea.. but the $$$ and work involved would be amazing.

[shep]

a dog box is what a outboard has, a motorbike has a sequential gearbox.

[Daz7]

JrZook wrote:

Sorry I'm an engineer but I base my conclusions on actual data and figures.

You seem to forget the total lack of a flywheel.

[royce]

shep wrote:

a dog box is what a outboard has, a motorbike has a sequential gearbox.

dog is how the gear engages, sequential is how the thing that moves the shift forks operates, a bike has both

[JrZook]

Daz7 wrote:

JrZook wrote:

Sorry I'm an engineer but I base my conclusions on actual data and figures.

You seem to forget the total lack of a flywheel.

??? Please explain?

Im going off the dyno chart of X motor with X flywheel it ran with comparing it to figures of Y motor with Y flywheel it ran with.

A ft-lbs of torque on engine X with X flywheel is the exact same thing as again A ft-lbs of torque on engine Y with Y flywheel.

Yes/no? What am I missing here?

[Ben_Sierra]

JrZook wrote:

Ben_Sierra what the hell do you base your assumptions on?? The internet?

Going from the dynochart that sideways posted up, busa engine absolutely pisses all over a G13a/ba in torque everywhere in its rev range!!

To put it into perspective the G13ba's peak power is around ~50Kw (67Hp) at 6500RPM and peak torque of ~75ft-lbs @ ~4000RPM. Now look at the busa dyno chart. 80% of the G13ba's peak torque (60ft-lbs) at any anywhere on the rev range. At 4000RPM the busa is already above the stock G13 figure and continues to rise until ~7000RPM!


Even the power curve of the busa is wayyy better than the G13 at lower RPM's. The busa is on par with the maximum output of the G13 nearly 2000RPMs less.

So again please explain your assumption? You have an engine that has a nice, flat, broad torque curve that kills the G13 anywhere in the rev range. You have more overall power anywhere in the rev range than the G13 and you have nearly double the amount of usable revs.

Sorry I'm an engineer but I base my conclusions on actual data and figures.

Sorry, the Sierra has 102Nm at 4000rpm, the Busa has about 5Nm on it at that point... 5Nm is hardly pissing all over it, is it... The G13 torque curve wouldn't drop away quite so much below 4000rpm either... Which is where I do all my crawling, not at 7000rpm plus.

And that torque curve shows a maximum torque of about 130, a long way short of the 154 "claimed".

Also, in order to overcome the gearing of the busa box, you'd need a 7:1 reduction in HIGH range just to match the stock Sierra gearing. That's not gonna be easy to achieve either.

BTW, I am also an engineer, however I deal in real life not theoritcal situations in university labs...

[ball]

Ben_Sierra wrote:

JrZook wrote:

Ben_Sierra what the hell do you base your assumptions on?? The internet?

Going from the dynochart that sideways posted up, busa engine absolutely pisses all over a G13a/ba in torque everywhere in its rev range!!

To put it into perspective the G13ba's peak power is around ~50Kw (67Hp) at 6500RPM and peak torque of ~75ft-lbs @ ~4000RPM. Now look at the busa dyno chart. 80% of the G13ba's peak torque (60ft-lbs) at any anywhere on the rev range. At 4000RPM the busa is already above the stock G13 figure and continues to rise until ~7000RPM!


Even the power curve of the busa is wayyy better than the G13 at lower RPM's. The busa is on par with the maximum output of the G13 nearly 2000RPMs less.

So again please explain your assumption? You have an engine that has a nice, flat, broad torque curve that kills the G13 anywhere in the rev range. You have more overall power anywhere in the rev range than the G13 and you have nearly double the amount of usable revs.

Sorry I'm an engineer but I base my conclusions on actual data and figures.

Sorry, the Sierra has 102Nm at 4000rpm, the Busa has about 5Nm on it at that point... 5Nm is hardly pissing all over it, is it... The G13 torque curve wouldn't drop away quite so much below 4000rpm either... Which is where I do all my crawling, not at 7000rpm plus.

And that torque curve shows a maximum torque of about 130, a long way short of the 154 "claimed".

Also, in order to overcome the gearing of the busa box, you'd need a 7:1 reduction in HIGH range just to match the stock Sierra gearing. That's not gonna be easy to achieve either.

BTW, I am also an engineer, however I deal in real life not theoritcal situations in university labs...

What am I missing here??


Are you thinking the engine (crank)is directly coupled the sierra gearbox or the output shaft of the busa engine is connected to the gearbox.

If you use the bike gearbox as well then you should have more than enough reduction.

Who cares what the engine rpm is.

You aren't comparing apples to apples here.

[Ben_Sierra]

I was assuming that you use the Busa sequential box instead of the Sierra box...

I have just noticed a mistake in my calculations, however you would still need at least 6.5 gears to make it drivable on stock tyres...

Sure, if you use the bike box and the Sierra box it would be good...

[JrZook]

Ben_Sierra wrote:

Sorry, the Sierra has 102Nm at 4000rpm, the Busa has about 5Nm on it at that point... 5Nm is hardly pissing all over it, is it... The G13 torque curve wouldn't drop away quite so much below 4000rpm either... Which is where I do all my crawling, not at 7000rpm plus.

Where did you get this info?

Ben_Sierra wrote:

BTW, I am also an engineer, however I deal in real life not theoritcal situations in university labs...

Lol what's that got to do with it? I know you are an engineer.

I was having a dig at your blank statement of the engine is utterly useless off-road when you had no explanation or any torque curves to base it off and wondering how you got that conclusion for an engineer . Maybe from the above post I'm thinking, which btw is wrong any way. Max power is at ~10000, torque at 7000.

Max torque figures are never a good number to go off as its only one point in the RPM range. It may just have that peak and no plateo surrounding it, which would make it a useless engine, even if the 'peak' is at ~1000RPM.

[got_bar_work]

6.5 and 5.12 would be enough gearing
And if u ran a auto in the middle
U would just run the bike box in 4th on the road
I u needed more torque then just smash it back to 2 on the fly and get it higher in the rev range
Can't you also get this motor with a turbo

[got_bar_work]

Also if u are worried about low down torque just get the torque converter moded for a 3800 rpm lock up

[Ben_Sierra]

JrZook:

I have seen a Sierra torque curve a long time ago and it was pretty flat from 2000 onwards... Unforunately I can't find it now...

Perhaps useless was not the correct word...

Certainly, not worth the effort would be a fairly accurate description in my opinion. In that Lotus 7 replica on the plrevious page I can see it being great, in a Sierra, I just can't see it's worth it...

The funny thing is with all these "awesome engine conversions" that gets me whenever anyone suggests one is why?

I drive on all sorts of terrain in my G13BA Sierra, and the thing is, I always run out of traction before I run out of grunt... On the street is the only place it could use some improvement, and even a G16A would provide more than enough to cruise at 110, I don't understand why anyone would want anything more than a G16B, it just isn't worth the effort...

Thats my $0.02 anyway...

[Jasen]

Is it just me or do most bike powered zooks i see on youtube seem to spin wheels uncontrolably and not be able to take technical lines? Could be just the drivers, but to me a bike engined zook doesn't seem to suit the kind of 4wding I like doing (slow, precise wheel placement etc). Would prob be great for sand and mud but just too wild for the slow technical shit.