Jump to content
SAU Community

Rb25/34

Morgz32

By Morgz32,
in Engines & Forced Induction

 Share

Recommended Posts

Morgz32 Collaborator

Morgz32

Posted
Posted

hey guys

im in the works of planning a 25/34 build to go into my 34 GTT, im sourcing parts prices etc but one thing that im questioning is the neo head. Ive built a 25/30 for my 32 using a 33 series 2 head which i got the water gallery welded, and a external oil feed for the lifters is the neo head requiring the same work? im sure the water gallery has to be welded but is there anything different between a neo head opposed to the 33 head that needs to be addressed for this conversion??

thanks

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/
Share on other sites
Morgz32 Collaborator

Morgz32

Posted
  • Author
Posted

would it be worth using a 33 series 2 head? i assume the majority of the 34 wiring harness is the same as the 33?

i had a 25/30 in my 32 originally had a 25 in it, and when i got it tuned the tuners said it had a 34 wiring harness

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6602374
Share on other sites
jangles Veteran

jangles

Posted
Posted

would it be worth using a 33 series 2 head? i assume the majority of the 34 wiring harness is the same as the 33?

i had a 25/30 in my 32 originally had a 25 in it, and when i got it tuned the tuners said it had a 34 wiring harness

34 head is far better, just allow for the 34 when choosing pistons etc.

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6602518
Share on other sites
KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

what do you mean by allow for the 34?

What Jonathon said - the Neo head has a smaller combustion chamber than the R33 so you need to take that into account when calculating your compression ratio. Should be fine with the extra capacity of the 3.4 block - Neo is the superior head. Look forward to seeing the result!
Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6603125
Share on other sites
r33_racer Grand Master

r33_racer

Posted
Posted

The lifters will be fine. Just use the correct oil restrictors. We converted our r33 s2 head to solids and I made two 1.1mm restrictors using m8 grub screws. Has worked fine so far. This is on a spool rb34 stroker also.

As they said already you just need to cc your chambers and get the pistons to suit so your compression doesnt go sky high. Otherwise no worries!

Be prepared for a nice fat torque and power curve. From our old rb30 our whole power curve moved to the left by a good 1000rpm and we picked up something like 160hp more through the midrange. Makes the car so much nicer to drive.

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6607090
Share on other sites
harks Collaborator

harks

Posted
Posted

what is the approximate additional cost in block prep to fit the 34 crank in? the spool site mentions there is some minor modifications required to make it fit.

i'm looking at a 26/34 conversion into my 32 GTR down the track (when i get the $$ for it) was weighing up a 2.8 stroker but leaning towards going all out with the 34 since im more looking at low end torque and dont want to wait till 4.5k rpm for boost.

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6608666
Share on other sites
KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

ahhh ok that makes sense im getting a spool kit for my build, out of curiosity what did you set your compression ratio at?

thinking of using a JUN pump

Mine is a bargain basement build with stock pistons resulting in about 8.2:1 CR :/

As yours will be fully forged etc something well north of 9:1 or even more if you are going to run E85 would be good!

I have an N1 pump but don't limiter bash and have 7000 max rpm.

Jun sounds good - Tomei may be better but people swear by Nitto pumps - no experience of them myself!!

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6608779
Share on other sites
KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

what is the approximate additional cost in block prep to fit the 34 crank in? the spool site mentions there is some minor modifications required to make it fit.

i'm looking at a 26/34 conversion into my 32 GTR down the track (when i get the $$ for it) was weighing up a 2.8 stroker but leaning towards going all out with the 34 since im more looking at low end torque and dont want to wait till 4.5k rpm for boost.

The pictures on their site show a small amount ground away for the extra clearance needed for the 3.4 - looks like a very small job - less than 15min labour.

Go the 34 - I want to see more results!!

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6608781
Share on other sites
MRHD66 Rising Star

MRHD66

Posted
Posted

The pictures on their site show a small amount ground away for the extra clearance needed for the 3.4 - looks like a very small job - less than 15min labour.

Go the 34 - I want to see more results!!

spool RB32 don't need any clearance and unlike the nitto RB32 stroker the spool on is a 3.2l
Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6608872
Share on other sites
JonnoHR31 Grand Master

JonnoHR31

Posted
Posted

spool RB32 don't need any clearance

So? The extra capacity of the 3.4 comes from a longer stroke. Longer stroke means a larger diameter crank, which naturally needs more room to spin around.... What's your point?

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6609218
Share on other sites
MRHD66 Rising Star

MRHD66

Posted
Posted (edited)

So? The extra capacity of the 3.4 comes from a longer stroke. Longer stroke means a larger diameter crank, which naturally needs more room to spin around.... What's your point?

was just saying some people don't like machining the block for Clearance as it weakness the block a bit Edited by MRHD66
Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6609521
Share on other sites
blue_vl_t Rising Star

blue_vl_t

Posted
Posted

It will be interesting to see more results, I've only ever come across the spool s15 dyno graph. It's a good thing. Is there any other 3.4L results you guy know of?

I like the idea of the 3.4, considering its really the same cost as going 2.8 from a rb26, obviously exept the mods to fit an rb 30 in your car.

What rpm are you looking to turn this to?

Link to comment
https://www.sau.com.au/forums/topic/412621-rb2534/#findComment-6611019
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • MBS206
      Anyone have this problem with their temperature gauge?

      By MBS206 · Posted

      I'm with GTS, that's not an actual overheat issue. That's an electrical issue.
    • GTSBoy
      Anyone have this problem with their temperature gauge?

      By GTSBoy · Posted

      So, it's clearly an electrical problem. Either with the gauge itself, or the sender. It appears to be voltage sensitive (ie, alternator output affects the reading.
    • LaurelPWR
      Rb26- Enlarging Std Throttle Bodies

      By LaurelPWR · Posted

      Yes, at this stage of SAU threads, I  automatically assume that anyone here knows that everything depends on each and every setup and its choice of parts and what an individual wants from the setup. I think your misunderstanding what I've said, I'm not saying your curve will move to the right.. I'm stating the opposite; that my setup has a much larger turbo than my last one, my current exhaust manifold runners are 2-3x longer than the last one, the intercooler is longer and thicker (hks 103mm thick), the itbs are now oversized from 45mm up to 49mm, and the plenum is now a larger Nismo plenum that's been port matched. As a result, I'm making more power, torque and boost 1000rpm earlier than my last setup. My curve moved left, in a big way. You guys with 800-1000+hp turbos should be considering hks v-cam or the other Japanese company Sakura who makes RB25 Neo vct adaptor kits for RB26's. they all make more power / boost / torque far earlier and higher peak numbers. Dahtone Racing modifies the Hks v-cam systems to his own specs and he also developed the worlds first and best dbw individual throttle body kits, to complement his V-cam. Every single car is 800-1200+hp and they all produce huge gains in response and peak power. 
    • juanX
      Anyone have this problem with their temperature gauge?

      By juanX · Posted

      I have a 2008 Skyline 370gt with about 160,000 km on the clock currently. A while ago, I noticed the temp gauge would start climbing but it comes down when I give it some throttle. I took it into the shops. The technicians comments are transcripted below. Reported they couldn't find anything wrong with the vehicle mechanically and they pressure tested the cooling system. Funnily enough, the technician commented that the temperature dropped back down when the car is stationary but this is when I'd notice the temp gauge to be climbing. Just wondering if anyone else experienced anything similar to enlighten me? Cos at the onset, the temps were going up one tick and then comes back down when I step on it. Now, the temps are climbing all the way to the top of the gauge, and it's making me very nervous lol. It also doesn't come down to the neutral position anymore. PS I do have a small exhaust leak near the drivers side caused by when I got f**ked by a really steep driveway at a mall I never visited before. Not sure if this would affect the sensor. Technician comments: Check and verify Fan/Cooling system - ALL OK max 106*C and fans operating at 100% Cools down right away. Checked Fan Operation - 55%@101*C, 85% @ 104*C and 100% @ 105*C Vehicle did not exceed these temperatures with max load. Temperature recovered back to 99*C after fan operation while vehicle Stationary.
    • Predator1
      Rb26- Enlarging Std Throttle Bodies

      By Predator1 · Posted

      It really depends on your setup. Mine is 'accidently' more suited to revving higher. bigger cams, turbo etc. Plus my super long first takes donkey years to come onto boost, so if it will move my power band to the right, maybe i'll pass on this. i have a G45-1500 going on there soon which I suspect might make it more of a fat pig.
×
×
  • Create New...