Leeroy_25

The first time I got involved with the RX7 (about a year ago) I asked around here in the UK if anyone had ever put a RB26 motor into one.. I gather V8 and V6 conversions are quite common place but thats loosing a bit of the japanese heart of the machine.. I thought putting an RB26 which is an awesome motor would be a great plan. However I was told that it was not possible for various reasons. After a lot of searching around I have found there are a couple such conversion in the states. I would really like to know some information on this conversion or if someone has a build thread for one even better.. I am very seriously thinking about doing it if I can get a cheap donor car. I have most of a spare rb26 engine so I would be insane not to I reckon!

Cheers guys

Lee

parid

Finding an RB26 would be the least of your worries. Theres going to be a ton of fab and wiring involved. Are you ready for that?

Ottoman

yeah i'ts been done

and just as much a PITA as a 2jz swap

lucky for u.. ur streering rack is on the right rather than the left where the turbo sits

dgeesaman

iTrader: (7)

https://www.rx7club.com/sitemap/t-235560.html

http://www.nissansilvia.com/forums/i...253593&hl=rb26

rXzach93fd

iTrader: (1)

check out my build thread, im doing an rb25 in an fd, if you have any questions feel free to ask me, i had to cut the steering rack out space it down about an 1''1/2, make custom mounts for everything, custom oil pan, it fits pretty good, the shifter almost lines up in stock position and it has plenty of clearence from the firewall, i mnot finished yet, but will be soon.....good luck!

Leeroy_25

Thanks for the info guy's. Firstly regarding the wiring surely not matter what conversion you do there is oging to be lots of loom wiring hel to deal with! unless you go back to carbs that is!
Fabby wise I would be surprised if you didn't have to do some.. I would be interested to know if you use the FD subframe and whether you use the fd box with an adapter or a RB25 box?
Half the fun is the challenge.. so far I have drawn blanks in the UK and a number of people have said that they have never heard of anyone doing it in the UK yet. So damn sure I would like to be the first! I like doing things on a budget to which adds some more interest! Yes an RB26 motor is fairly easy to get here but it would set you back £2000 easy! if not more.. so around $4000. If I am lucky I can get a donor car with a blown motor for $1000 then I have plenty of scope to play with! I like to have something different! So I fancy trying to custom up some bodywork as well.
I wil be checking out these links and probably asing plenty of questions about the 25 conversion. Are you using the standard inlet and so on? the general ancillaries and so on make te R25 a fair bit narrower in standard form.
Please post a link to your build thread so I can have a look.. Very interesting!

Miata_mx5

If you are going to keep it relatively stock, you should be fine.

Start modifying it for power and track duty, look into investing another at least 3000 Pounds in fixing all the RB's oil sumping/lubrication problems alone.

Better off with a toyota motor if you just want a cheap, reliable fast car.

Leeroy_25

Is this coming from a man that owns a R32 GTR!?
I am just getting ready to build an RB30 conversion.. I have picked up an N1 Oil and water pump for £150 each. The main weakness is supposidly more the pump drive collar than the pump itself.. You can get a larger drive collar for £30. ANd then if you are going for track use you'll probably want to baffle the sump and maybe get a sump extension.. Can all be fabbed DIY if you have the skill or worst case can be picked up for like £500 on the forums. What oter lube problems were you thinking of??

Miata_mx5

Don't get me wrong. The RB is a great engine, and i love it for what it is. But it has it's share of weaknesses (a bit of them too).

For track duty and high revving, there are 5 things that need to be done to make the RB26 SOLID (Lubrication wise). Water cooling is not usually an issue.

The oil and coolant galleries in the block need to be drilled to allow more fluid. Machine shop can do this.

The head needs an oil drain return from the head to the sump.

The ONLY oil pump that is known to work for the most part is the Tomei Oil Pump. The Jun, nismo, n1, all the other oil pumps have failed. Even the endurance racecars are only using dry sump because that is the only bulletproof way of doing it. The Tomei pump used toyota technology (much beefier parts) for the RB. The Tomei one is at least 700 Pounds.

You need an Oil Gallery Orifice.

You need Tomei, Trust or Nismo Oil Pan baffles to help the sump pickup.

http://forums.freshalloy.com/showthread.php?t=161095

This applies to all engines: RB20, 25, 26, and 30. When i build another engine, i intend on doing all of the above as well.

Side Notes: Metal Head Gasket IMO is a must, and for heavy track use the Mine's Triple Flow Cam Cover is recommended too.

http://www.mines-wave.com/english/CA...FFLE_PLATE.htm

This is the MINIMUM to do it right for heavy duty track work/high revving big power applications. Stock, or DD use, not so much is needed.

This is all if you want to do it right, and i am picky about the way i like to do things. Better to err on the side of caution.

Take apart a 2jz-gte/1jz-gte and an RB26DETT and you can see obvious design flaws in the RB that Toyota did right from the factory. The RB and GTR Chassis together are great. From a powerplant standpoint, Nissan IMO could have done much better.

Leeroy_25

Well thank you for the link first off. I have some of that information already for my build.. but good to have it al in one place! I did actually get the link earlier on the RB25 conversion thread. Nice to have it here though.

I agree with what you saying for the most part.. it cannot be denied that there is the weakness and yes Nissan should have done a bit more RnD and then they would have had a real dimaond motor. But as you also point out for general use it is pretty damn good and only normally suffers if it goes to the track. In my case I will not likely track my cars.. show and possibly a track day.. But I do intend to take the precautions where I can. I like doing things right but sadly I don't have the mass budget some do.. So I try to find alternatives or next bests!

I am actually about to build an RB30/RB26 hybrid as I bought a R33 V-sepc that had a seized bottom end! When I have the bottom end appart i'll post some pics! Then we can all have a chuckle!
Thanks for the info though and like the banter too!

Does anyone know who the guy that has done the RB26 FD3 with the mega wide body conversion is.. I would really like to have a chat with him or see a build thread if he has one?

Miata_mx5

Go to freshalloy.com

and PM VeilsideS14.

If i remember right, he was the one that did it. If he still is on that forum.

reman13b

iTrader: (1)

2jz is little easier, cause the turbo is on the other side. also 2jz can be bar'd.

Leeroy_25

Thanks for that Miata, I managed to find Veilsides14 after numerous googles last night! He is on here also. Hope he replies to is pm!

Reman, I am in the UK with a RHD car so the turbo set-up of the RB is probably better for me in that respect.

rXzach93fd

iTrader: (1)

it doesnt matter either way, they are both just as easy, just get ready to do a lot of custom fab work

Leeroy_25

Sounds like fun to me!

What sort of things have you come up against so far? I have seen your thread.. and was expectinf to custom fab or mod the following.

engine mounts
gearbox mounts
diff mount/brace
propshaft.
exhaust system
did you run the FD diff? maybe a skyline diff would be an option?? then even more custom work to do!
Will you get away without moving the rack in your new planned setup?

Anything major I have missed?

Cheers
Lee

Miata_mx5

I highly recommend you set aside money for a GOOD oil pump. It's expensive, but it will save you a motor. If you don't have the money for a new Tomei oil pump, you don't have the money to fix a blown motor.

I do recommend the XS Engineering RB Throttle body seals as well. Good, Cheap insurance against a boost leak as w/e engine you will get will have it's seals shot due to age. PM XSDAILO on Freshalloy for those.

PS: You can read about all the N1 oil pump failures on freshalloy.

If you are getting a pre-Oct 93 RB26, i do recommend upgrading to an R33 or R34 GT-R Crank so you get the wider oil pump drive.

Only the Tomei one is the only good one that is known to last the longest for street use. I had a friend with an N1 pump fail 2 months ago. This makes 6 N1 pump failures this year alone. 3 of them were just normal driving.

http://forums.freshalloy.com/showthr...ht=N1+Oil+Pump

Worth the read.

rXzach93fd

iTrader: (1)

i am using the fd rearend right now, you will need a custom oil pan to go with your list, i am not messing with the steering with this swap..

this thing has not really been that hard, i took the steering out to set the engine in place, lined up the shifter and gave clearence around the firewall, got the engine where i wanted and welded up some mounts for the motor, tranny, and diff, put the steering back in and thats where i am at right now, it will be about done in 2 weeks...

Leeroy_25

Cheers for that.. will keep a check on your progress.. have you got a pic of yor sump/oil pan?

Miata. I am about to build an RB30 using N1 upgrade water and oil pumps! Best hope it stays together.. what's the point in the upgrade if it's no good?? I am sure if there was that big a floor in the pump it would have been pulled by now?? You say there are failures which I don't doubt but then there are hundreds/thousands out there that are running perfectly fine. maybe the percentage of people that can actually afford to upgrade to an N1 verses a tomei or similar has something to do with that? i.e there are way more N1 pumps out there on motors than any other upgrade I would guess. I bet if you dug you would probably find failures on the dearer ones too..

Miata_mx5

All the oil pumps are known to fail. The only one that works and that is bomb proof is a dry sump.

This topic has been covered over and over here in the states and japan.

Water pump is usually never an issue. Oil Pump is. Since you said you have a siezed R33 Bottom end, if you are using the R33 Crank you should have the wider drive as well.

Even the guys at Nismo Omori Factory say the N1 Oil Pump is useless.

It's just a strong warning. It will be a lot more expensive than 800 pounds to fix a broken motor than invest in a good pump. Beat on the Tomei one long enough, it will fail too. Something about the RB motors and tearing through oil pumps. They tested the Tomei one at a 24 hour endurance race for a 12 hour stretch, after 11 hours it failed. But the rest all took a **** a long time before that.

But out of ALL of them, the tomei one is known to last the longest and the most durable for most street use.

rXzach93fd

iTrader: (1)

you will be fine with rb, pumps dont fail unless you don't know how to set up your car, i have had many rb's

gripp2maxx

here thank me later.........

https://www.rx7club.com/showthread.p...highlight=rb26


http://forums.freshalloy.com/showthread.php?t=172517

gripp2maxx

i almost did this but ls2 is way better option if your not gona stay 13b........i was on the stay jap drive train but the lsx motors is one of the best built engine's hands down!

Narfle

iTrader: (16)

1) wrong
2) what does a "set up" have to do with an oil pump?
3) I doubt youve even seen one

rXzach93fd

iTrader: (1)

ok

Miata_mx5

Tell that to the guy with the R32 GTR who had his New N1 Pump fail 2 weeks after building his motor. He cheaped out on the build, now he will spend another 6000 dollars on good engine parts, and a Tomei Oil Pump + an Accusump and do it the right way.

Says the guy who says you can get 450 whp out of a stock turbo Non-Neo RB25DET. Most people are upgrading turbos go get 430-480 whp out of any RB25 period.