Engine + Gearbox Selection

[Yakboy]

Hi guys,

I postd this on the main skyline forum, but had a second thought that there may well be some top experts over here in WA, so be gentle

I would like some expert opinion, if possible, to my problem.

I'm designing a new off road racer, trophy truck, full spaceframe, independent front, 3 or 4 link rear axle, 20-26 inches of suspension travel, somewhere in the region of 2 - 2500kg all up weight, less if I can acheive it.

I researched using a Skyline some 8 years ago back in the UK, but the rework on the gearbox for my design made it a non starter, now I'm out here, older and hopefully wiser and am investigating drivetrain options.

The norm is 355 chevy and a TH400 auto box, but I'm not for following the crowd....... like to push the envelope somewhat. Yeah its painful sometimes but success brings so much satisfaction.

Class rules limit engine size to 6L, so if theres a turbo in the equation I have to multiply engine size by 1.7 hence a 2.8 turbo * 1.7 = 4.76L overall. I have been advised already to possibly utilise an RB25..... but I am not up to spead with all the different configurations of engine/gearbox and differing chassis.

I have been scouring this forum and many other websites, looking for answers, but having no experience in the nissan arena I thought it would be best to get into the open and put my problem forward.

So if anyone has opinions, ideas, technical and any thoughts on the matter, i would be most appreciative.

I've attached a naked photo and a fully dressed photo of two yank racers so you have an idea of where I'm designing.

I thank you in advance......

Nige

[bubba]

RB30DET with a Spool 3.4L crank/pistons setup (when they start getting sold to the public).

Manual or auto?

[gazza750]

RB30 ET with a getrag 6 speed sequential ?

comes out about 5.1 litres

[Yakboy]

RB30DET with a Spool 3.4L crank/pistons setup (when they start getting sold to the public).

Manual or auto?

Bubba, I was thinking auto as we only have two feet, I've raced both over the last 14 odd years, there are pluss's and minus's on both, but its governed more on the reliabilty side of things...

OK whats an RB30DET out of?? please excuse my ignorance but whats a "Spool"

and...

(when they start getting sold to the public) you got my hopes up !!!! I take it they are not available??

thanks for your time

nige

[Yakboy]

RB30 ET with a getrag 6 speed sequential ?

comes out about 5.1 litres

Hi Gazza750

What chassis or model would this be out of??

whats the cylinder capacity?

There is a configuration which replaces the clutch with a torque converter, could this be done with a getrag box? at this stage I can only assume you change gear with a blip in throttle at the same time?? trying to find out more info on that..

thanks for your time anyhow, very much appreciated guys

nige

[Nic_A31]

With that kind of weight, don't bother with an RB...or with anything less than 3.0

If you're going 6 cylinders, find a VQ...you can get them in up to 4.0 displacement stock form, they're a shitlaod lighter and produce tons more torque than RBs, they can handle low-mid boost very well, not soo well at high boost unless you do some work to the heads.

I can vouch for VQ30DEs...can keep up with a 6L HSV with minimal effort, and without going anywhere near its 6600rpm redline.

If you want high boost, the VGxxDE (T)(T) might be on the cards...they're a bit heavier, being an iron block, but can support 1000+hp reliably with stock internals...it'd be hard to pull those kind of numbers out of one, but the reliability is more so what you're after...I've never seen a VG blow other than due to neglect.

[bubba]

Bubba, I was thinking auto as we only have two feet, I've raced both over the last 14 odd years, there are pluss's and minus's on both, but its governed more on the reliabilty side of things...

OK whats an RB30DET out of?? please excuse my ignorance but whats a "Spool"

and...

(when they start getting sold to the public) you got my hopes up !!!! I take it they are not available??

thanks for your time

nige

Hi Nige,

An RB30DET is a hybrid engine using the bottom end from a VL commodore/R31 Skyline (Aus delivered, 3L single overhead cam, 6cyl.) and the twincam head from an RB25 or RB26.

Spool is a trader from over east who I got the rods for my RB30DET from, he is currently trialling a couple of 3.4L stroker setups.

As for the gearbox, not sure what way to go there.. you could use the auto out of a VL commodore as I'm sure there's plenty of people around that can build those up or maybe the tiptronic auto out of the R34 skyline.

Any rules about 4WD?

[Yakboy]

Hi Nige,

An RB30DET is a hybrid engine using the bottom end from a VL commodore/R31 Skyline (Aus delivered, 3L single overhead cam, 6cyl.) and the twincam head from an RB25 or RB26.

Spool is a trader from over east who I got the rods for my RB30DET from, he is currently trialling a couple of 3.4L stroker setups.

As for the gearbox, not sure what way to go there.. you could use the auto out of a VL commodore as I'm sure there's plenty of people around that can build those up or maybe the tiptronic auto out of the R34 skyline.

Any rules about 4WD?

Guys, thank you so much for your info, its priceless, just what the doctor ordered..

rules on 4WD, urm i'm looking at 2wd Extreme as a class, cos there are no limits on design,except the body must substantially resemble a mass produced vehicle. I'm not completely set against 4wd, my last car in the uk was a scubie 2lt turbo and 5 spd box (modified), fully independent suspension front and rear, and permanent 4wd. scared the s**t out of me as it was 400kg lighter than the street version. But I'm looking at building something different this time..... theres so much up in the air, decisions decisions......

[Dsturbd]

VH41 v8 .. sell you one reallll cheap

[Yakboy]

With that kind of weight, don't bother with an RB...or with anything less than 3.0

If you're going 6 cylinders, find a VQ...you can get them in up to 4.0 displacement stock form, they're a shitlaod lighter and produce tons more torque than RBs, they can handle low-mid boost very well, not soo well at high boost unless you do some work to the heads.

I can vouch for VQ30DEs...can keep up with a 6L HSV with minimal effort, and without going anywhere near its 6600rpm redline.

If you want high boost, the VGxxDE (T)(T) might be on the cards...they're a bit heavier, being an iron block, but can support 1000+hp reliably with stock internals...it'd be hard to pull those kind of numbers out of one, but the reliability is more so what you're after...I've never seen a VG blow other than due to neglect.

Hi Nic,

you are a star, VQ sounds pretty good, don't have too much experience in the boost area, my scubie was as standard as they come, if like you say they are lighter and tons more torque then my ears are perked..... I really require good torque low mid but not so much high I guess, need to be able to pull from corners rather than outright overall speed, in our sport its more won in the turns rather than the straights, but don't get me wrong, top speed is important too, its the whole packaqge that makes the difference on lap times. ah yes, lap times = 20km plus !!!!!

I digress....

so what would a VQ30DE be out of?? need to search for donors etc etc

thanks again

[Dorigecko]

VQ30DE would be out of an A32 and a33 nissan maxima sir. you'll need to adapt maybe like a z32 5spd or auto to it (300zx), but it'd go hard man.

VG30DETT out of a 300zx in general would be immensely good. quite a bit heavier, but fkn bulletproof.

Agreed, for naturally aspirated VQ30DE, VQ35DE from a 350z or J31 maxima or nissan murano.

Also - VH45DE from an infiniti Q45. Yeehaw!

[Yakboy]

VH41 v8 .. sell you one reallll cheap

Ha ha nice one, give us a bit more to go on???????

VH41..v8 ?? wheres that come from? gearbox config??

yeah an Price ?????

[Yakboy]

VQ30DE would be out of an A32 and a33 nissan maxima sir. you'll need to adapt maybe like a z32 5spd or auto to it (300zx), but it'd go hard man.

VG30DETT out of a 300zx in general would be immensely good. quite a bit heavier, but fkn bulletproof.

Agreed, for naturally aspirated VQ30DE, VQ35DE from a 350z or J31 maxima or nissan murano.

Also - VH45DE from an infiniti Q45. Yeehaw!

Hiya, so from your excellent list, I could get a VG30DETT and auto box out of a 300zx, but this would be a "heavy" option

or...

VQ30DE out of a maxima but have to adapt the gearbox

any idea of a ballpark weight figure for both engines??? rough guess is good enough for me......

thank you for your input, its fantastic....

nige

[Dsturbd]

Ha ha nice one, give us a bit more to go on???????

VH41..v8 ?? wheres that come from? gearbox config??

yeah an Price ?????

PM sent

[bubba]

2WD Extreme class with no limits on mods.. go the VH41 and twin turbo it!

But the reason I ask about 4WD is (yes, I know it would be a HUGE task with lots of sensors and electronics to swap but hey.. if it was done to a VL 10 years ago.. why not give it a bash in a buggy?!), get a wrecked GTR and transplant the driveline/ATESSA setup with a bigger engine in front of it..

[Tony de Wonderful]

With that kind of weight, don't bother with an RB...or with anything less than 3.0

If you're going 6 cylinders, find a VQ...you can get them in up to 4.0 displacement stock form, they're a shitlaod lighter and produce tons more torque than RBs, they can handle low-mid boost very well, not soo well at high boost unless you do some work to the heads.

I can vouch for VQ30DEs...can keep up with a 6L HSV with minimal effort, and without going anywhere near its 6600rpm redline.

If you want high boost, the VGxxDE (T)(T) might be on the cards...they're a bit heavier, being an iron block, but can support 1000+hp reliably with stock internals...it'd be hard to pull those kind of numbers out of one, but the reliability is more so what you're after...I've never seen a VG blow other than due to neglect.

I'd imagine the RB would be easier to fit, cheaper and easier to get trick parts for and boost up a bit? It's more of a known quantity...proven reliability.

[Yakboy]

2WD Extreme class with no limits on mods.. go the VH41 and twin turbo it!

But the reason I ask about 4WD is (yes, I know it would be a HUGE task with lots of sensors and electronics to swap but hey.. if it was done to a VL 10 years ago.. why not give it a bash in a buggy?!), get a wrecked GTR and transplant the driveline/ATESSA setup with a bigger engine in front of it..

Hey Bubba,

nice idea, whats a VH41 out of?? scuse my ignorance !!

If say I took everything out of a 4wd GTR as you say, and transplant the driveline, is it possible to do a 2wd variant??

I welded up the rear LSD in the back end of my scubie box, because it was s rear engined configuration with a reverse rotation transfer box, the front wheel drive wasn't needed, wouldn't work from the back of the car anyhow. This was done because taking drive from only the rear output shaft, the front diff would just spin and you wouldn't get any drive out the back....

Could this method also be done withan AWD nissan box?? just gives me options in choosing to go down the 4wd route and not 2wd......bigger choices..

I'm not the least bit worried about engineering things, I can design the frame around anything, thats why its termed "spaceframe" in my mind, just want to design into the car, the reliability, good power and torque and not too trick because of getting hold of replacement parts..

Engine size is somewhere about 3.4L 3.5L turbo'd of course, is this readily available??

cheers

nige

[Nic_A31]

I'd imagine the RB would be easier to fit, cheaper and easier to get trick parts for and boost up a bit? It's more of a known quantity...proven reliability.

Just as easy to fit a VQ...theyre alot better and worth the little hassles, and "support" isnt a big deal for serious racers.

RBs are great for street cars, since every mofo has one...RBs arent great, theyre just alot mroe common and easier than any other engine...their potential is actually pretty crap when you look at what other Nissan engines can do.

Look on wiki for where theyre used.

VQ20 and 25s arent on any Aussie market cars..overseas Cefiros used them and I think the Stagea used the 25HR.

30s are used in A32 - A34 Maxima, also in alot of Cedric/Gloria/Cima, etc

VQ30DE-K is used in A34 Maxima (improved externals)

VQ35DE is in J31++ Maxima and 350Z

VQ40DE is in the new Pathfinder I beleive.

VH45 is in some Gloria's, Leopards, I think either Cedric or Cima had the option before V8 became standard, as well as Infiniti Q45s (before it became VK41DE in i think 96+)

Thats all I can recall off the top of my head without checking Wiki (at work....)

[Tony de Wonderful]

RBs arent great, theyre just alot mroe common and easier than any other engine...their potential is actually pretty crap when you look at what other Nissan engines can do.

You need to don your flame suit after that heresy.

Too be honest I can't refute the idea of VQ's being 'a lot better'...but I've heard of people easily blowing pistons w/ a bit of aftermarket boost. Sure there are more powerful engines than the RB's but they are pretty good for street cars at the end of the day. They are reliable, strong, bits and pieces are plentiful etc...they just want to be boosted up.

[Nic_A31]

Exactly my point...RBs are great for street performance and mild pro track use....the real pro's go and find other engines...like VQs.

Getting power from any engine is easy...but its a whole lot easier when you have more power and response to start with...and in that field, VQs win over RBs, hands down....the RB has plenty of potential, especially built 3.0s...but I think VQs will always have way more horizon. Likewise with the V8s...i test drove a few Q45s and they're f**kin' awesome...gave it a few squirts rolling from 30 and it got to a hundred in maybe 2 seconds ? if that ? not bad for a 4.5 litre engine in an 1800kg car