Nice RB25 1989 300ZX on eBay...

[1CLEANCOUPE]

Dam I wish I had the money to get this one. I seen it in person and is sick...

http://cgi.ebay.com/ebaymotors...wItem
Modified by 1CLEANCOUPE at 9:11 PM 5/27/2007

[tg]

I'll take some torque instead thx.

[nsrZ32]

Um....that's a Z31....from the 80's. Not a 1991.

[1CLEANCOUPE]

Um....that's a Z31....from the 80's. Not a 1991.

Yeah sorry is an 89 I love that body style I copy and paste the (91) but yeah I seen that car in person looks good and is fast.

I'll take some torque instead thx.

I'm not sure what you mean about toque??? RB26?

Can a mod move this on the correct Z section please...Sorry guys

[mtcookson]

I'm not sure what you mean about toque??? RB26?

A VG can make a lot more torque than an RB. The big comparison that comes to mind is the Pentroof Skyline and Z. Both modded equally (i.e. massive amounts of work), the RB made only 10 hp more than the VG30DETT but the VG... made over 300 lb. ft. more torque than the RB.

Exact numbers:

RB26DETT:759.9 hp @ 7,820 rpm543.2 lb. ft. @ 7,000 rpm

VG30DETT:746.5 hp @ 6,550 rpm865.8 lb. ft. @ 4,550 rpm

Difference:13.4 hp more for the RB322.6 lb. ft. more for the VG

I'll take a VG over an RB any day.

[bone_stock_240]

woah! Why the huge difference in torque? I was under the false impression that inline 6 made more torque than a V. I know some of it is due to the 400 mL difference in displacement, but what other factors contribute to it?

[AZ-ZBum]

RB26DETT:759.9 hp @ 7,820 rpm543.2 lb. ft. @ 7,000 rpm

VG30DETT:746.5 hp @ 6,550 rpm865.8 lb. ft. @ 4,400 rpm

Those are impressive numbers and all, but not nearly a good comparison. It's pretty clear the RB was built to rev the piss out of. Note the 7800rpm peak power. I'd guess they set the redline at around 8500 rpms. You can't say that the RB doesn't make any torque just because it wasn't built to make low end torque. I'm sure if someone wanted to, they could build a lower revving RB that makes tons of torque down low. A lot of factors will contribute in how much torque an engine makes. And just throwing out two big number engines is not a good comparison.

Also, since we're on the subject, why not compare the original Z31's engine with the RB25DET that is installed?

VG30ET:200hp @ 5200 rpms227 ft-lbs @ 4300 rpms

RB25DET:250 hp @ 6400 rpms217 ft-lb @ 4800 rpms

[bt2s14]

Why would you put so much work and money into something like that to end up

selling it and losing money/time.

[1CLEANCOUPE]

Why would you put so much work and money into something like that to end up

selling it and losing money/time.

I talk to the guy and he's selling the car because he just found a 92 R32 GT-R Skyline for a good price. I think that's a really good reason to take the loss and sell the Z...

[mtcookson]

Those are impressive numbers and all, but not nearly a good comparison. It's pretty clear the RB was built to rev the piss out of. Note the 7800rpm peak power. I'd guess they set the redline at around 8500 rpms. You can't say that the RB doesn't make any torque just because it wasn't built to make low end torque. I'm sure if someone wanted to, they could build a lower revving RB that makes tons of torque down low. A lot of factors will contribute in how much torque an engine makes. And just throwing out two big number engines is not a good comparison.

Its a good comparison for what was being questioned, which was the torque the VG makes over the RB. The RB has a shorter stroke than the VG making the biggest difference in the way it delivers power, being the lower amounts of torque production but being able to rev quite high. Take the RB30 now... that one has a very good chance of making more torque than the VG. 1 mm less bore but 2 mm more stroke.

The VG and RB I listed above, like I mentioned, have nearly identical mods. The RB has a 1 mm larger bore while the VG has the stock bore. Turbos are identical between them being Trust TD06-20G's, cams are very similar in specifications (270 duration with 10.25 mm lift for the VG, 272 duration with 10.5 mm lift for the RB). But yeah, like you said the RB could easily be made to be a lower revving, torque monster engine. The RB30 should be able to pull that off quite easily. Mod for mod though, the VG should almost always be able to make more low end torque than an RB26 or any of the other smaller RB's . You will always have things like for instance over sized turbos that can change that but in most cases it will be true. Just the way the engines were designed.

I personally wouldn't mind the smoothness of an I6, but they're tall and long making packaging a little more difficult in some cases, so unless I bought a car with one, I'd stick with my V engines.

Here's the link to the two engines listed above (first two cars on the page): http://www.ooparts-internation...ecord/