Converting an RB to triple carb set up

[gearhead55]

I recently sold my RB25 s13 and I am missing it. I am thinking about what I would like to build next and I am leaning toward something classic.

I've seen the Rocky Auto cars and such that have carbureted RB25s and 26s, but I can't find any information on them in English. Do they use high comp pistons? What kind of power are they making? Are high comp pistons for an N/A build available in the US? Or cams designed for N/A use? And are there any carb conversion kits available on this side of the pond? I can't find anything through my searches.

Basically I'm just looking for that old school look with velocity stacks and that classic N/A sound but with some useable power. Any information on prices and power numbers would be greatly appreciated.

[S12 Drifter]

I would like to know this, when I get my hakosuka one day iKd wanna do a rb20ds itb carb and compression of 12.1

Sent from my SPH-M920 using Tapatalk 2

[dawagarage]

sounds like a lot of work aka either a lot of money, and/or ingenuity, know how and fab skills.

find out what head they used, thatll be a start.

you MIGHT be able to bolt an old L series head to the RB block, but if that were the case then you might as well just put a L series engine in your car.

as for pistons, etc, im sure youd have no problem finding whatever piston you desire stateside. BOTH piston design and head design will dictate compression. and for that, you might have to do some math if you cant find anything readily available

[S12 Drifter]

sounds like a lot of work aka either a lot of money, and/or ingenuity, know how and fab skills.

find out what head they used, thatll be a start.

you MIGHT be able to bolt an old L series head to the RB block, but if that were the case then you might as well just put a L series engine in your car.

as for pistons, etc, im sure youd have no problem finding whatever piston you desire stateside. BOTH piston design and head design will dictate compression. and for that, you might have to do some math if you cant find anything readily available

you can bolt a RB head on a L block but NOTHING lines up.... literally.

[dawagarage]

well if he wanted to run carbs it would be easier to bolt the L head to the RB block (not the other way around) but if it doesnt line up the way you said, it wont line up the other way either.

i say just go for running a full L!!! itll be super inexpensive, plentiful parts, all you gotta do is fit it in the pay and get the motor mounts, to work and get it to bolt up to whatever trans

[zerodameaon]

I looked into this some few years, it appears most of those carbs are one off setups so its very doubtful you will find any kits.

[gearhead55]

well if I was going to use an L series head I would just use an L28. I've heard of 3.2l stroker L28s making 300whp. My reason for using the RB25 is the dual cam head. I like the look/history of the S20 motor. From the pictures i've found it looks like the Rocky Auto cars are using regular RB25/26 heads just with custom manifolds.

RB30, looks like RB26 head, Solex(?) carbs:
S30Z RB30 - ‹ŒŽÔE–¼ŽÔ(ƒnƒRƒXƒJEƒPƒ“ƒƒŠEƒtƒFƒAƒŒƒfƒB [ZEGT-R)‚̐ê–å“X ƒƒbƒL[ƒI[ƒg (http://rockyauto.co.jp/stockcar/profile.cgi?_v=1360292947&tpl=car)

RB25 head, Solex(?) carbs:
ƒXƒJƒCƒ‰ƒCƒ“ RB25ƒXƒ|ƒCƒ“ - ‹ŒŽÔE–¼ŽÔ(ƒnƒRƒXƒJEƒPƒ“ƒƒŠEƒtƒFƒAƒŒƒfƒB [ZEGT-R)‚̐ê–å“X ƒƒbƒL[ƒI[ƒg (http://rockyauto.co.jp/stockcar/profile.cgi?_v=1360203453&tpl=car)

RB25 head, Solex(?) carbs:
h7wN-5Epi9U


I looked into this some few years, it appears most of those carbs are one off setups so its very doubtful you will find any kits.

hmmm I see.

[EvilRB]

^ LOL
I was thinking of that samw car when I say this thread

I would actually looking into the the RB30 a little, I think there are kits made for the motor for the older skyline crowds and it just would be bad ass to seee one here
OR maybe it was another one of Rocky Auto's kits...
IDK it's just soemthing I remember reading in a thread long time ago in a forum far, far away...

Way to think different!!!:bigok:

Ninja Edit: just noticed your local, If you ever get this project off the ground and need help, Let me know I'll come by and lend a hand!

[KiLLeR2001]

Looks like gearhead is suffering from post-traumatic two-tone separation anxiety disorder (PTTTSAD), seen this all too often I'm afraid...

[gearhead55]

Way to think different!!!:bigok:

Ninja Edit: just noticed your local, If you ever get this project off the ground and need help, Let me know I'll come by and lend a hand!

Thanks! it will be months before I even pick up a motor if I decide to go this route, but i'll keep you in mind.

Looks like gearhead is suffering from post-traumatic two-tone separation anxiety disorder (PTTTSAD), seen this all too often I'm afraid...

Hahaha yes I am. I'll leave the two tone life to you for now. Your car is too clean haha.


anyway here is this, the motor is shown at 1:50:
RiJH3qPQjFI



and this is the video that makes me want a dual cam motor:
2LC_4J1MmRU

If that head was possible to obtain that is the route I would go, regardless of what power it would make, solely for the rad-factor.

[Sileighty_85]

yeah that Z is running a RB30 Bottom and 26 head, failrly common in AUS and other High HP builds as the head will bolt to the block you just need to relocate the timing belt pullys

If your really lucky you could get yor hands on the Autech R32 RB26DE which was Naturally aspirated. 10.5:1 compression ratio and produced 217 bhp

[S12 Drifter]

L's make some pretty impressive power N/A if done up right, but are insanely expensive though, but on the plus side parts are extremely plentiful.

[EvilRB]

You should just get this and start the project

http://zilvia.net/f/cars-sale/516606-1981-280zx-fairlady-rhd-so-cal-91316-1st-1500-takes.html

[fliprayzin240sx]

Did you say NA carb'd RB?

http://zilvia.net/f/builds-builds-only/428454-krome-s14-n-rb-test-build.html

[OrangeVirus1]

you can get a RB20DE non T Intake manifold with individual throttles and stacks for about 800$ straight from Japan.

get that along with a RB20, Have some custom 17 or 18:1 compression pistons made and run it on E85 or LPG Propane

( or do the same with any of the RB's )

[gearhead55]

Did you say NA carb'd RB?

http://zilvia.net/f/builds-builds-only/428454-krome-s14-n-rb-test-build.html

I found that when searching, but that's not carbureted. Read the thread, it's using RB26 ITBs. ITBs are still EFI.


you can get a RB20DE non T Intake manifold with individual throttles and stacks for about 800$ straight from Japan.

get that along with a RB20, Have some custom 17 or 18:1 compression pistons made and run it on E85 or LPG Propane

( or do the same with any of the RB's )

What RB20 ever came with ITBs? Do you have a link for that? I was thinking more like 12:1 with an RB25 on pump gas. I'm not really looking to run a 2.0l with a compression ratio crazy enough to require more than pump gas.

[OrangeVirus1]

I found that when searching, but that's not carbureted. Read the thread, it's using RB26 ITBs. ITBs are still EFI.




What RB20 ever came with ITBs? Do you have a link for that? I was thinking more like 12:1 with an RB25 on pump gas. I'm not really looking to run a 2.0l with a compression ratio crazy enough to require more than pump gas.

Nissan Skyline HCR32 RB20 itb Special Order Individual Throttle Bodies Japan | eBay (http://www.ebay.com/itm/Nissan-Skyline-HCR32-RB20-ITB-Special-order-Individual-Throttle-Bodies-japan-/140971428567?pt=Motors_Car_Truck_Parts_Accessories&hash=item20d28d4ad7&vxp=mtr)

linked up!

[zerodameaon]

I was thinking more like 12:1 with an RB25 on pump gas. I'm not really looking to run a 2.0l with a compression ratio crazy enough to require more than pump gas.

That sounds like a pretty fun NA.

OV is about to turn this into an argument for the RB20 and its reasons for being better than the RB25 and up.

[OrangeVirus1]

That sounds like a pretty fun NA.

OV is about to turn this into an argument for the RB20 and its reasons for being better than the RB25 and up.

no I'm not.

[gearhead55]

Nissan Skyline HCR32 RB20 itb Special Order Individual Throttle Bodies Japan | eBay (http://www.ebay.com/itm/Nissan-Skyline-HCR32-RB20-ITB-Special-order-Individual-Throttle-Bodies-japan-/140971428567?pt=Motors_Car_Truck_Parts_Accessories&hash=item20d28d4ad7&vxp=mtr)

linked up!

very cool, thank you. I wonder how much fab work would be required to put this on an RB25 head. Not quite carbs but similar.



That sounds like a pretty fun NA.


Yea I think it would be.

[4x4le]

you can get a RB20DE non T Intake manifold with individual throttles and stacks for about 800$ straight from Japan.

get that along with a RB20, Have some custom 17 or 18:1 compression pistons made and run it on E85 or LPG Propane

( or do the same with any of the RB's )

These are diesel compression ratios

[OrangeVirus1]

These are diesel compression ratios

Yes they are, but they are safe on E85/98 or LPG propane.

On Gasoline, no.

[stacksondeck]

Here we go again. Show us one Nissan running 18:1, Virus.

Your retarded 'info' never ceases to amaze.

[OrangeVirus1]

Here we go again. Show us one car Nissan running 18:1, Virus.

Your retarded 'info' never ceases to amaze.

Retarded info? or your blantant inability to read? ( and blantant inability to construct intelligent sentences )

How about fucking try again you fool.

This is a perfect fucking example people, Perfect fucking example. Subject A: StacksonDick Blatantly miss-reads what I post, then Starts with personal attacks. Perfect fucking example of the etiquette that is Zilvia.

I said CUSTOM PISTONS.. Did I ever .. EVER fucking say there is a Nissan with 18:1 compression..

DID I?

Now go fucking kill yourself.

[stacksondeck]

Hahaha aren't you leaving the forum?

Soooo, if no Nissan has them then how do you know enough to tell someone to use them? Did you tune a car with 18:1 compression?

We love it when you get mad Virus :) makes my day knowing your life is shit.

[OrangeVirus1]

Hahaha aren't you leaving the forum?

Soooo, if no Nissan has them then how do you know enough to tell someone to use them? Did you tune a car with 18:1 compression?

We love it when you get mad Virus :) makes my day knowing your life is shit.

Are you really that retarded to not understand what custom pistons are?

No nissan Comes stock with custom pistons.. BUT YOU DID NOT FUCKING KNOW THAT?

It was a mere fucking suggestions you retarded fuck. did you even tune your car AT ALL? Do you even understand the aspects that is tuning? Ignition timing? Air to fuel ratio? Exhaust temps? Volumetric efficiency ?

Like I said, Go fucking kill yourself.

my life is great haha thanks.

perfect fucking example people. StacksonDick. Perfect example of the shit I'm talking about. I say something, Directed at nobody, I get personally attacked because the person is too fucking retarded to know what custom pistons are.

[stacksondeck]

Lol I think you're missing the point. Have you EVER tuned, driven, seen a car with 18:1 c/r?

Don't try to change the subject. Just eat your words and tell us what they taste like.

[OrangeVirus1]

Lol I think you're missing the point. Have you EVER tuned, driven, seen a car with 18:1 c/r?

Don't try to change the subject. Just eat your words and tell us what they taste like.

Dude please tell me you really aren't THIS retarded.. please.

OMG NO THERE IS NO CARS IN EXISTENCE WITH COMPRESSION RATIOS THAT HIGH.... oh wait.. Diesels.. what the fuck?

I've never personally tuned that high of a compression ratio on E / LPG but it isn't impossible.

You don't understand what 1. a suggestion is. 2. Custom pistons are.

Go fucking kill yourself.

[dawagarage]

can yall take that shit to PM and keep this thread on topic?

i was really interested in where this was going

[dawagarage]

so much so that it reignited my desire to stuff a z motor in my truck. its been done, but is not very common, and you gotta do a lot of digging to find anything about it.

here are some photos :)
http://www.bleachgarage.com/images/620gallerymod/gallery510.jpg
http://www.bleachgarage.com/images/620gallerymod/gallery513.jpg


http://www.bleachgarage.com/images/620gallerymod/gallery696.jpg
http://images.craigslist.org/3Mb3J53Na5I25F65M7d5adc438440428318d3.jpg

the problem is the L6 is just too damn long.
you either have to relocate the radiator to the rear,
or you have to cut the fuck into the firewall.

anyways, back lets get back on topic :)

[gearhead55]

so much so that it reignited my desire to stuff a z motor in my truck. its been done, but is not very common, and you gotta do a lot of digging to find anything about it.

the problem is the L6 is just too damn long.
you either have to relocate the radiator to the rear,
or you have to cut the fuck into the firewall.

anyways, back lets get back on topic :)

What kind of truck do you have? I've even seen L28s squeezed in to 510s before, so I guess anything is possible.


Anyway, here is some carb goodness:

FCR set up on an L28 (2.9l):
0P5mm5LTh2c


I believe these are FCR carbs on an L28 (the description says FCR, but they look different than other FCRs that i've seen, so I dunno):
iAF9jE5QMbI


This is a cool video of a bunch of different carb set ups on 4age AE86s. The MSR carbs look and sound awesome, but i've never heard of them before. FCRs are awesome as always, the expression on the guys face after driving them is classic (5:30):
fLqHxl4Qewc


I'm not sure why FCRs always rattle at idle....

[gearhead55]

I also just found this:
N/A is the only way.. | (http://datsunikon.wordpress.com/2013/04/16/na-is-the-only-way/)

[dawagarage]

same as the one pictured, datsun 620
(also listed in my sig, silly ;) )

[Yellow4g63]

Carbs? i remember those.
qzOJj4UR-jU&list=UUP5RDENWil7XYYHmuGNPdoQ&index=93

[gearhead55]

same as the one pictured, datsun 620
(also listed in my sig, silly ;) )

Oh whoops haha. Yea an L28 would be much more fun than the L16. My first car was a 510 with an L20 with dual weber carbs and a dog leg 5 speed. That car was so fun.


Carbs? i remember those.
qzOJj4UR-jU&list=UUP5RDENWil7XYYHmuGNPdoQ&index=93

Now that's what I'm talking about, old school is best school. Do you have any info on that set up? Internal mods or power numbers? Looks like RB26 but I can't tell what carbs.

[Yellow4g63]

gear it's a RB25DE with RB26 valve covers. I can't remember what the HP numbers were it's been a while. I don't remember where he got the ITB's(no carbs)from but he is running a Microtech stand alone.

[gearhead55]

gear it's a RB25DE with RB26 valve covers. I can't remember what the HP numbers were it's been a while. I don't remember where he got the ITB's(no carbs)from but he is running a Microtech stand alone.

Ah gotcha. Now that I look closer I can see that it's an ITB set up.

[S12 Drifter]

Bro if you're trying to replicate a S20 get a RB20DET you keep the oil squirters... not that they matter.

do 12.5:1 like you wanted. go ITB tripple carb's. and you can keep the ecu use it for ignition.

the RB25 will never replicate a legit S20 that was used in the race car hakosuka. sure the displacement is nice but it's not the same experience as the little S20.

[S12 Drifter]

Here we go again. Show us one Nissan running 18:1, Virus.

Your retarded 'info' never ceases to amaze.

THE LD28 YES A DIESEL version of the L28 I believe a RB diesel as well sohc. i believe Z24 came in diesel.

and yes the US DID get a LD28. it ran 22.1 or 20.1

[gearhead55]

Bro if you're trying to replicate a S20 get a RB20DET you keep the oil squirters... not that they matter.

do 12.5:1 like you wanted. go ITB tripple carb's. and you can keep the ecu use it for ignition.

the RB25 will never replicate a legit S20 that was used in the race car hakosuka. sure the displacement is nice but it's not the same experience as the little S20.

I'm not trying to replicate the performance of the S20, I'm really just looking to replicate the LOOK of the S20. After driving my miata for a while i'm really missing the torque of my old RB25.

About using the ECU for ignition; does anyone know if I would be able to keep a rev limiter using the ECU to cut spark at the desired RPM? I would be a little worried to run a motor without any form of rev limiting.

[gearhead55]

P3k4yyHU9ZY

[EvilRB]

LOL... Randomly searching came across krome's car... though of this thread...

Tag Archive for "Exhaust Manifold" - Lazy Rocket (http://www.lazyrocket.com/tag/exhaust-manifold/)

As for your question I think you can but I think you can use something like Nistune or you can use something simple like a Bee-r rev limiter

[gearhead55]

LOL... Randomly searching came across krome's car... though of this thread...

Tag Archive for "Exhaust Manifold" - Lazy Rocket (http://www.lazyrocket.com/tag/exhaust-manifold/)

As for your question I think you can but I think you can use something like Nistune or you can use something simple like a Bee-r rev limiter

That car is cool. It's like half of what I am thinking. I would like to see what kind of power it would make with a high comp bottom end.

Another way to increase compression that I was reading about on miata forums is shaving the head down. Has anyone heard of this done with RBs?

[EvilRB]

I think that is exactly what one of the engines that rocky auto did with their 25/ head on a 30 block combo was... I'd have to find it. you should try asking the guys on JNC these questions they might have a better insight...

Japanese Nostalgic Car • View forum - Datsun/Nissan Garage (http://japanesenostalgiccar.com/forum/viewforum.php?f=7&sid=2dbd877c6cec5be6649e1fce1a2c0e3c)

[gearhead55]

I know the rocky auto carbon Z with the RB30 block is carbureted, I dunno about any others.

I've never checked out the JNC forum, I should've looked there haha. I'll search there for a while.