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All Motor Rb????


Guest turdbo

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ok we'll iv been lurking around here for a while and i love the RB swap its my favorite out of any swap in any car...im building a road races / daily driver Z car and i was wondering if anyone has ever seen an all motor RB engine??..i have been researching alot about it and think im going to give it a try

 

Engine:

RB20Det ( converted to N/A )

different head with cam and new valve train ( rb 25 or 26 head if compatible )

lightened crank

lightened flywheel

ARP bolted everything

BMW M3 individual throttle boddies

Megasquirt ECU

fully custom headers and exaust everything blue printed and balanced

and fully forged bottom end

ect. ect.

 

i was hoping of getting the car to REV out extremely high adn make decent power for the road course

 

do you guys think it would be worth it building something like this?

any opinions or suggestions thanks-Zach

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Engine:

RB20Det ( converted to N/A )

different head with cam and new valve train ( rb 25 or 26 head if compatible )

lightened crank

lightened flywheel

ARP bolted everything

BMW M3 individual throttle boddies

Megasquirt ECU

fully custom headers and exaust everything blue printed and balanced

and fully forged bottom end

ect. ect.

 

Take a good look of what you just said and you'll see that there's a way to simplify things a bit.

First, you say you want M3 ITBs and Maybe an RB26 head. Instead, buy a complete RB26 head with intake and you'll allready have those ITBs.

ITBs M3s were never sold in the U.S. (I think) so, you'd have to find some in Europe or from a Canadian E36 M3 and they'll command a pretty impressive price, I know, cause I work at BMW.

 

Another thing to think about is the RB24 "this is a relatively unknown engine, as it was not produced for the Japanese domestic market. These were fitted to some left hand drive Nissan Cefiros exported from Japan new. Mechanically it is made from an RB30E head, RB25DE/DET block and RB20DE/DET crank with 34 mm height pistons. This engine used carburretors instead of the Nissan ECCS fuel injection system. This has the outcome of it being able to rev harder than the RB25DE/DET (as it has the same stroke as the RB20DE/DET) as well as being almost the same displacment as the RB25DE/DET. A common modification is to fit a twin cam head from other RB series motors while retaining the carburreted set-up. The standard single cam form produced 141 PS @ 5000 rpm and 20.1 kgf·m (197 N·m) of torque @ 4400 rpm."

(the parts between quote marks was taken from wikipedia)

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The easiest and most powerful N/A RB will be an RB30 bottom end with an RB26 head. High comp forged pistons can take you over 10:1 C/R and the RB26 head has factory throttle bodies already on it, simply remove the intake plenum. This is the set up I am currently working on myself. There are a number of guys getting close to 300hp out of a 3 liter L series. An RB will flow much more air with it's twin cam head, so having a comperable displacement and C/R would most likely yield well over 300hp. Not to mention probably a lot mor throttle response. The other option is to simply buy a N/A RB25 as they are all over the place. Have an adapter made if you want TB's or carbs. An N/A RB25 puts out around 160hp I think.

 

Brian

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well the reason i said i wanted to use bmw itb's is beacuse i have access to them rather easily from working at the race track..and the 2.0 would be more capable to rev higher because of the rod length i figured if you put a really good flowing head on the 2.0 block and bullet proof it..it should be able to do some damage

 

btw i didnt know rb26's came with itb's

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Guest captaincaveman
well the reason i said i wanted to use bmw itb's is beacuse i have access to them rather easily from working at the race track..and the 2.0 would be more capable to rev higher because of the rod length i figured if you put a really good flowing head on the 2.0 block and bullet proof it..it should be able to do some damage

 

btw i didnt know rb26's came with itb's

hmm, well I have heard of rb26s reving really high so I doubt you really need that shorter stroke and longer rods to pull off an excellent NA rb motor. Um one thing though. Where are you going to get NA aftermarket cams :confused: These engines are turbocharged from the factory, so I would think most aftermarket cams would be for turbo applications. Just wondering, I'm sure there's a company that makes them though

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lots of company's can make custom cams..and anyway i could always get NA cams and get them reground..so im not worried about that im just curious about different head design's among the RB engines

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The RB25DE puts out 187 HP @ 6500 RPM and 170 ft/lb @4800 RPM with 10 flat compression.

 

Thats what im running right now for my daily driven car. Pretty tourqy engine down low and punchy up top. Lacks mid range but then again im completely stock.

 

You can find RB25DE's anywhere for cheap too. I picked mine up complete for 900 usd.

 

let me know if you need info, i'd be glad to help and see what kind of power you can make from an NA RB.

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Your stated goal is a daily driver, with occasional track usage, and the motors you are talking about in NA form put out less than 200 hp. Why spend that much on a full blown swap to get less power for much more money than you can achieve with the stock L6? There are tons of documented 2.8 and 3.0/3.1L motors putting out near or greatly more than 200 hp to the wheels and they weigh less than a RB swap. It just doesn't make sense. I say go with a solid known and build a solid NA L6. Increased weight in a RB tranny and RB motor isn't worth the minimal gain in power over a STOCK 2.8L motor.

-Bob

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Your stated goal is a daily driver, with occasional track usage, and the motors you are talking about in NA form put out less than 200 hp. Why spend that much on a full blown swap to get less power for much more money than you can achieve with the stock L6? There are tons of documented 2.8 and 3.0/3.1L motors putting out near or greatly more than 200 hp to the wheels and they weigh less than a RB swap. It just doesn't make sense. I say go with a solid known and build a solid NA L6. Increased weight in a RB tranny and RB motor isn't worth the minimal gain in power over a STOCK 2.8L motor.

-Bob

 

 

First of all an NA RB swap is a fraction of the money and work you have to put in compared to a DET swap. I know youve done a DET swap and i can tell you its nothing even close to that. Second your talking about near 200hp in STOCK form. I don't know of any NA L24/26/28/3+ that came with that much HP in STOCK form. The RB has more potential to grow as an NA engine becuase of a better flowing head.

 

Also, he did say he wanted it to be a daily driven car, so i'm sure efficiency is a must. It's very unlikly that an carbed L engine with webers, mikuni's or su's can be more efficient than the fuel injected RB.

 

Furthermore, a stock RB25DE + tranny and all electronics weighs 35 LBS more than a su'd L28 w/ headers + 5 speed. I know, because I weighed everything myself. Shift the weight further back than the L28 and your good. If weight is your biggest issue, then toss the stock iron manifold for a nice stainless peace, toss the large intake minfold for some ITB's , throw on a lightweight flywheel and that almost covers the difference.

 

The RB is is undisputedly a more advance engine than the L and has far more potential to make more power. I don't see why you think RB's HAVE to be turbo or nothing.

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Parts avilibility isn't a BIG factor. I can't think of one thing that's different from an RB25DE and DET. Intake/exhause manifolds, cams, spockets, clutch/fly, water/oil pump, etc.. the parts are all interchangable.

 

The only drawback I see the the PRICE of the parts becuase there is no reference to the RB in the states so all parts would come form over seas.

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  • 1 month later...
Guest TeamNissan
The easiest and most powerful N/A RB will be an RB30 bottom end with an RB26 head. High comp forged pistons can take you over 10:1 C/R and the RB26 head has factory throttle bodies already on it, simply remove the intake plenum. This is the set up I am currently working on myself. There are a number of guys getting close to 300hp out of a 3 liter L series. An RB will flow much more air with it's twin cam head, so having a comperable displacement and C/R would most likely yield well over 300hp. Not to mention probably a lot mor throttle response. The other option is to simply buy a N/A RB25 as they are all over the place. Have an adapter made if you want TB's or carbs. An N/A RB25 puts out around 160hp I think.

 

Brian

 

Actualy I believe its a rb30 bottom end with rb25de head and pistons. rb25de non vvt head is the only 100% direct bolt on and using the rb25de pistons give you a comp of 11:1. A few people in the aussi forums claim 250hp with a matching completely liniar tq stats with just that done. Toss some cams, headers maybe some itbs and I would be thinking you would be close to 280hp. Thats the rt I'm personaly taking too so I'll be sure to post weather the aussies are full of ♥♥♥♥ or not :-).

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RB30-ZED, a member on classiczcars (mayb here too?) has got an rb30 in his car with an rb25de vvti head i believe

 

one of my mates put an rb25det into his vl commodore (the engine all the rb30's come out of) and has now put the rb30 block back in with the 25 head, and says for the money he's now spent he could of, and should of bought an rb26dett, and thats with him doing all the work, so i think he must of upgraded a few things

 

there are also a couple of guys in aus building up rb30dett's (possibily converted to single turbo) for their 240z's i think, they have websites, not sure of the links sorry.

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Guest TeamNissan
RB30-ZED, a member on classiczcars (mayb here too?) has got an rb30 in his car with an rb25de vvti head i believe

 

one of my mates put an rb25det into his vl commodore (the engine all the rb30's come out of) and has now put the rb30 block back in with the 25 head, and says for the money he's now spent he could of, and should of bought an rb26dett, and thats with him doing all the work, so i think he must of upgraded a few things

 

there are also a couple of guys in aus building up rb30dett's (possibily converted to single turbo) for their 240z's i think, they have websites, not sure of the links sorry.

 

Ya to run the vvt head you have to weld shut the stock oil gally then tap it and run a oil line from the oil sender. thats if you want to keep it vvt, which I would. I think most people end up using vvt anyway since non vvt rb25de's are such a pain to come across.

There are alot of ways to run the rb30, I mean a turbo 3.0 is great but the post was all motor :-/. Its not really a max hp thing... If I was going bang for buck I would have bought the supercharged lt1 I saw on ebay the other day for 2k lol. I think if you go all motor your just looking for something dif. Just my opinion anyway.

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  • 2 weeks later...
Guest turdbo

ya i know what you mean..im interested in all out power for this project not huge nubers but enough power to know its their and its right at the pedals no lag ...i work at a road couse and have owned turbo cars an rx7 and now im trying a z but taking the N/A route i think it should be a good idea im shooting for 300hp with vvt ...anyway if anyone has any tips on where i can find decent parts maybe engine rebuilds or rebuild parts let me know....btw im in the states

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  • 2 weeks later...
Actualy I believe its a rb30 bottom end with rb25de head and pistons. rb25de non vvt head is the only 100% direct bolt on and using the rb25de pistons give you a comp of 11:1. A few people in the aussi forums claim 250hp with a matching completely liniar tq stats with just that done. Toss some cams, headers maybe some itbs and I would be thinking you would be close to 280hp. Thats the rt I'm personaly taking too so I'll be sure to post weather the aussies are full of ♥♥♥♥ or not :-).

Are you sure they are 11:1 compression? I've read the SAU thread and I can't find any reference to that combination yielding that kind of compression.

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