RB25 Swap
09-26-2005, 01:12 AM
#2
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you'll need the 200zr crossmember and engine mounts. if not make your own. the 200zr had the rb20det in it, and all rbs bolt to the same mounts. the vg30 version of the 5 speed will not bolt up to it, you'll need an rb series gearbox.
in the end its well worth it though.
in the end its well worth it though.
09-27-2005, 06:10 AM
#5
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you obviously havent driven a skyline or an rb20det powered car before than, would you say no to an rb26dett just because it has less litreage? point taken? Well IMHO its a very very good swap. power is easyer to obtain too.
Tho add an intercooler exhaust intake and boost to a VG30et and you've allready got a good performaing engine.
Tho add an intercooler exhaust intake and boost to a VG30et and you've allready got a good performaing engine.
09-27-2005, 01:35 PM
#6
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The VG30ET can make some pretty serious power with stock internals. It's a good motor. Why go through all the hassle when you can make some very decent power with the engine you have? Power is not easier to obtain, really. Why do you think this? You do know that the VG30ET puts out more torque than the RB25DET at only 200HP? Torque is what you want. HP means nothing without it. By the time you get done doing the swap, and working out the bugs, and getting more power out of it, you'll have spent more time and money than it would take to build one beast of a VG30ET.
Last edited by SloppyGoat; 09-27-2005 at 02:04 PM.
09-27-2005, 04:35 PM
#7
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im just looking at my options becuase this is a project car, it doesnt hav eto be runnning anytime soon, so im just looking at everything.
I like the Vg30 but it only has two valve heads, still has a distributor, and some oiling issues which i need to find out about so i can maybe correct them.
I like the RB25 becuase along with power i am also looking into gas mileage, I beleive in a car to be power but controllable and effecient, so thats why i want the Rb25 becuase it has coil per cylinder, 4 valve heads, and it is a straight 6 and i have always liked the straight six design over a v6.
I havent researched it fully but i believe i can build a 300-350hp RB25 for about the same price as my VG30. MY transmission is gone in the 300 right now so i already have to get a transmission and im talking to a few dealers for rb25 pull outs and i think i can get one for about 2000 or cheaper.
Remember i would rather have a motor that is powerful but controllable and also effecient.
I like the Vg30 but it only has two valve heads, still has a distributor, and some oiling issues which i need to find out about so i can maybe correct them.
I like the RB25 becuase along with power i am also looking into gas mileage, I beleive in a car to be power but controllable and effecient, so thats why i want the Rb25 becuase it has coil per cylinder, 4 valve heads, and it is a straight 6 and i have always liked the straight six design over a v6.
I havent researched it fully but i believe i can build a 300-350hp RB25 for about the same price as my VG30. MY transmission is gone in the 300 right now so i already have to get a transmission and im talking to a few dealers for rb25 pull outs and i think i can get one for about 2000 or cheaper.
Remember i would rather have a motor that is powerful but controllable and also effecient.
09-27-2005, 07:43 PM
#8
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Okay, here's my take on it... yes, if I could do it, I would swap an RB20 into my car... but, as I'm buying an '84 NT, an an '86 Turbo. I have an '86 NT... so, I've also gotten my hans on a VG33, from an '01 Xterra.. I'm pretty good on the engine thing right now. But, yeah, if I could I would swap out any of the RB motors.., either an RB20, or an RB26. I don't want the RB25 for the simple reason, if you're going to fork out 3k for a 2.5, why not go out and get a 2.6 for 3,500. It's just wiser. Being as I don't know enough for the harness and body modifications... I'm just gonna stick with my VG33. At the current moment I've repaired the electrical problems I had with my Z, and I put in a new Deep cycle truck battery. If you look at it from the aspect of time and money... yeah, sticking with a VG series. But, It's like the guy who buys a CRX and puts in a B18... there's no point when he could be a teg... Be original, and do what you think is better for you car... if people were satisfied with keeping a stock engine, then there wouldn't be nearly the customizing done in the auto world... I say, if you want to do an RB swap, GO FOR IT! Hell, somebody needs to do it. and if you can do it, do the damned thing. That's just my two cents... take how you want it.
JD
JD
09-27-2005, 07:56 PM
#9
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Location: riverveiw,fl
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What if a part goes bad on the rb?Not even the dealership will carry these parts.
You will have to locate one overseas and have it shipped.Your car could be down for weeks over a faulty coilpack.
You can get 300 to 350hp for less than that rb will cost you.
Unless you want to be uniqe use the vg. It will save you alot of hassle.
You will have to locate one overseas and have it shipped.Your car could be down for weeks over a faulty coilpack.
You can get 300 to 350hp for less than that rb will cost you.
Unless you want to be uniqe use the vg. It will save you alot of hassle.
09-27-2005, 07:58 PM
#10
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I'd rather put the VG33 in it. It's more of a direct swap, and it's more displacement. For the money you're going to spend on a used RD25, you could rebuild your VG30 and beef it up a bit in the process. Then, you'd have new/reworked internals, and practically a new engine.
09-27-2005, 07:59 PM
#11
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That's why there is a Signal Auto in California... If you're an enthusiast... you would know this, if you know who Signal Auto is... they specialize in Nissan/Nismo parts and tuning... if you need an RB part, they will get it for you.
JD
JD
09-28-2005, 04:31 AM
#13
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Indeed...it's like ordering any other part from your local dealer, but no local...yes, it will cost you... but it makes it easier to get the parts. If you don't find it suitable, then don't do it. If 864v thinks it works for him, then it does. Don't ever destroy someone esles dream...
09-28-2005, 06:31 AM
#14
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Location: australia, tasmania
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oh i forgot you guys are from america lol, we have em everywhere in ausland!!! and i totally agree with the vg30et theory. Put it this was, a vg30et can make 200 HP with a clogged up exhaust and 6 psi boost. put the boost specs and tune it like any new turbo, and you have more power at your finger tips.
Boost, IC, exhaust, POD, ECU, you have a demon at your hands!
Add injectors, larger turbo, and your cracking bloody good numbers for 1/4 less that what you would on another engine.
Boost, IC, exhaust, POD, ECU, you have a demon at your hands!
Add injectors, larger turbo, and your cracking bloody good numbers for 1/4 less that what you would on another engine.
10-18-2005, 03:08 PM
#15
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Location: Oregon
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Originally Posted by SloppyGoat
The VG30ET can make some pretty serious power with stock internals. It's a good motor. Why go through all the hassle when you can make some very decent power with the engine you have? Power is not easier to obtain, really. Why do you think this? You do know that the VG30ET puts out more torque than the RB25DET at only 200HP? Torque is what you want. HP means nothing without it. By the time you get done doing the swap, and working out the bugs, and getting more power out of it, you'll have spent more time and money than it would take to build one beast of a VG30ET.
But your comment is bothering me. Mainly the comment on torque. I believe you just need the right drivetrain to take full advantage of the motor.
http://www.houseofthud.com/cartech/t...horsepower.htm
I would think the rb would be much better than the vg. The rb has an oversquare design so you can build a very high revving engine and the rb has a better head than the vg
10-20-2005, 10:51 AM
#17
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Originally Posted by Captain caveman
Sorry for reviving this old thread.(was looking for info on rb powered z31)
But your comment is bothering me. Mainly the comment on torque. I believe you just need the right drivetrain to take full advantage of the motor.
http://www.houseofthud.com/cartech/t...horsepower.htm
I would think the rb would be much better than the vg. The rb has an oversquare design so you can build a very high revving engine and the rb has a better head than the vg
But your comment is bothering me. Mainly the comment on torque. I believe you just need the right drivetrain to take full advantage of the motor.
http://www.houseofthud.com/cartech/t...horsepower.htm
I would think the rb would be much better than the vg. The rb has an oversquare design so you can build a very high revving engine and the rb has a better head than the vg
Any RB costs more than any VG motor, and getting performance parts as well as basic maintainance parts costs more.
Yes, the RB motors can be built well. But so can the VGs. Get a VG33 and do all the neat little tricks you would have done to the RB, and you'll be in it for less money and have more horsepower and torque.
No, you can't rev a VG over 8000 rpms (at least, not that I've seen), but 7k isn't so bad. Just have to know what you're doing.
Originally Posted by shawn86t
rb is DOHC so of course its going to have the advantage. RB aftermarket parts are a dime a dozen these days and are everywhere.
As far as the DOHC vs. SOHC, don't even go there. If DOHC were so great, EVERY high performance motor in the world would be using it. Guess what? There are still high performance, high power motors using pushrods.
10-21-2005, 04:18 AM
#18
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i agree with what your saying bloke, but relitively speaking i keep forgetting that im in australia, and that parts are hard to find for the earlyer model vg series whilst an rb20det would set the average guy back around 300 dollars. i can't walk into my local auto joint and ask for a gasket set for a vg30et without them having to order me one in after telling them what its from and what it is.
10-21-2005, 06:53 AM
#19
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Location: Oregon
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plus you don't even need to buy a running 300zx. You can buy one off of someone that blew theri engine or the car is just giving them to many headaches for dirt cheap and then buy a low mileage motor like an rb for it.
10-21-2005, 01:30 PM
#20
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Originally Posted by shawn86t
i agree with what your saying bloke, but relitively speaking i keep forgetting that im in australia, and that parts are hard to find for the earlyer model vg series whilst an rb20det would set the average guy back around 300 dollars. i can't walk into my local auto joint and ask for a gasket set for a vg30et without them having to order me one in after telling them what its from and what it is.
10-25-2005, 03:56 PM
#21
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Hm... after long consideration, AZ's right. It's not worth it. I figure, if you had a 200ZR or one of the many variations of the Z31 using an RB powerhouse. I suppose it'd be worth it to modify and tune this to no limit. Though... dropping an RB series motor into anything in the states that didn't come equipped with (which to my knowledge is.. NOTHING, unless you've imported ..say a Skyline?) is senseless. I've seen guys who pick up RB's off of ebay and do great things with them. Keep in mind, if you can't adapt it's harness to your car, you've got to use an aftermarket harnes, most likely an HKS F-ConV Pro. Or maybe an Accel or MoTec system. And yes... there's always the worry of parts repair and how difficult they are to come by in the states. There are still parts available for the VG's in Japan that can't be gotten into the states without knowing somebody who knows somebody... know what I mean? In short, an RB series engine, is a beautiful thing, though... an expensive hobby as well. I'd stick with USDM parts and engines unless you've got pockets fat enough to buy Jenna Jameson for a one-night-stand.
JD
JD
10-26-2005, 04:18 AM
#24
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Originally Posted by shawn86t
perhaps i should start shipping rb parts to the us and selling them off there lol.
