Jump to content
SAU Community

Greddy Plenum Spacer Info (Torque/midrange)

skylineking

By skylineking,
in Engines & Forced Induction

 Share

Recommended Posts

skylineking Collaborator

skylineking

Posted
Posted

Hi everyone, been searching forums & Google for a while now struggling to find detailed info on my question...

I have an r33 gtst (engine out currently) hks 3037s top mount & many other mods including a genuine greddy plenum. My question is how do I go about gaining the midrange loss back from the plenum? A few posts in various forums said a spacer between the plenum & the head. So this leads me to my questions below

1. How thick should the spacer be?

2. Did it cause any fittment issues?

3. Can you use the same bolts to fit the plenum back on or longer ones to suit?

4. to people who have done this was it really noticeable dyno/road feel?

I'm not here to get plenum choice advice or what somoneones opinion on my setup is or why plazmaman this & greddy that...... just trying to find info on the greddy spacer idea & if it works well.... To anyone who has done this please shed some light on this topic, tell us what car/engine u have & how thick the spacer is + what were your gains.... Thanks in advance

Ps hope everyone had a merry Christmas & have a happy & safe new year!

  • Replies 56
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

Ryno
Ryno

This is the setup I use..... As with any RB25DET plenum setup you will see that the coolant exits the block/head through the large orifice on the lower runners of the plenum. As a result the coolan

skylineking
skylineking

Awesome guys keep the posts coming!! Yeah I've been considering the whole injector thing & brake master issues....I was hoping there would be a few guys who have done the mod & can confirm for

skylineking
skylineking

I'm guessing that would be in a R34? That wouldn't make bugger all difference to the midrange. In a R33 you might have a bit more room but I think even at best 40mm wouldn't make much of a difference

Posted Images

Ben C34 Grand Master

Ben C34

Posted
Posted

Look at it this way, you have reduced runner length by heaps, a spacer will help a bit but not much compared to stock length, so I wouldnt expect a noticable result at all with a spacer.

skylineking Collaborator

skylineking

Posted
  • Author
Posted

Dammit Ben lol wasn't hoping to hear that haha nah cheers for the post mate I need to hear all the info on this so I can to see wether it's worth doing or not!

Gotta be a few people with RB25's, spacer fitted to their greddy plenum share your opinion/findings please

Blackkers Experienced

Blackkers

Posted
Posted

Another potential issue is moving the injectors back by the amount of the spacer. Not sure if it poses problems though.

An option would be to use the bottom half of the stock manifold and use a plazmaman style plenum which bolts up to that.

Ben C34 Grand Master

Ben C34

Posted
Posted (edited)

A while ago I had a jeep cherokee for some reason. Moment of madness.

Added a spacer under the throttle body as recommended by the Internet and car went substantially better. Spacer cost me nothing so I didn't care either way.

Inlet manifolds are weird things with all the science going on inside them!

I would give one a shot if cheap enough. I would not worry about moving the injectors back a bit, in some ways moving injectors back is a good thing.

I can help out if you want to get a spacer made. Even though I don't think it would be worthwhile!

Cheers

Ben

Edited by Ben C34
GTSBoy Grand Master

GTSBoy

Posted
Posted

I'm with Ben on both of his posts.

Think of the spacer as buying you back a fraction of what you lost.

If it were me, I'd be looking at whether I could turn the last couple of inches of a set of stock runners into a spacer. That way you can retain the injectors in the original location. Then make the cut off ends of the runners into a suitable head equivalent flange for the Greddy manifold.

But before I did any of that I'd look to see if there was enough clearance to the brake master etc.

skylineking Collaborator

skylineking

Posted
  • Author
Posted

Awesome guys keep the posts coming!! Yeah I've been considering the whole injector thing & brake master issues....I was hoping there would be a few guys who have done the mod & can confirm for us! Cheers Ben I'll keep that in mind man appreciate it. Gtsboy that's some good thinking there

  • Like 1
skylineking Collaborator

skylineking

Posted
  • Author
Posted

Here's another question I'd like to throw out there......... On an RB25neo with a 3076r & plenty of other bolt ons what would give the best mid range torque & spool time out of these 3 forward facing plenum options:

1. Plazmaman plenum

2. Greddy plenum with a spacer

3. RB26 plenum with itb's

& I'm not talking about throttle response I'm talking about best mid range/less lag plenum! Interested in people's thoughts cause they are my 3 options from here on in. People who have done any of these setups please share your thoughts & to any lucky (or should I say unlucky person) that has done a couple of different setups in the quest of best mid range ff plenum please share your pain & gain

Ben C34 Grand Master

Ben C34

Posted
Posted

I'm going to vote for plazmaman. Having never tried any but based on how much effort manufacturers go to to get long runners. Even on large v8s long runners very time. Factory cars want torque, long runners win.

skylineking Collaborator

skylineking

Posted
  • Author
Posted

That's what my thoughts were until I was reading about the 26 itb plenum & when blitz did it to nomuken's car they gained power accross the whole rev range..... Just not sure if it's all true cause plazmaman guarantee their results & some people didn't get good results using that plenum so I'm worried same thing will happen with 26 plenum

Here's the link by the way to the blitz info hard to read in jap lol

http://www.ricohracing.com/ricoh-home/ricoh-home/rb25henkan/rb25_6ren.htm

Ps I can buy an adapter decently cheap to be able to put the 26 plenum on so price isn't the issue its just what will work best?

skylineking Collaborator

skylineking

Posted
  • Author
Posted

Gtsboy that's what I was hoping to hear but it seems like the people who have spacers on their greddy's are no where to be found or just don't wanna tell us lol

Any dyno results would end all the head scratching hahaha

Dan_J Veteran

Dan_J

Posted
Posted

A while ago I had a jeep cherokee for some reason. Moment of madness.

Added a spacer under the throttle body as recommended by the Internet and car went substantially better. Spacer cost me nothing so I didn't care either way.

Inlet manifolds are weird things with all the science going on inside them!

I would give one a shot if cheap enough. I would not worry about moving the injectors back a bit, in some ways moving injectors back is a good thing.

I can help out if you want to get a spacer made. Even though I don't think it would be worthwhile!

Cheers

Ben

hey ben,

was that a plastic type spacer that would also shield the heat soak off the head or was it alloy ?

Ben C34 Grand Master

Ben C34

Posted
Posted

hey ben,

was that a plastic type spacer that would also shield the heat soak off the head or was it alloy ?

Alloy, and between the throttle and manifold so no heat soak benefits.

GTRPSI Mentor

GTRPSI

Posted
Posted

In a nut shell.....generally speaking.....

The rule is longer ports are better for bottom end range, shorter ports for top end range.

The opposite goes for runner diameter, smaller dia runners for bottom end, larger dia runners for top end.

So something for pulling down low would have long narrow runners, a screaming high rpm big power engine build would have short large diameter runners.

skylineking Collaborator

skylineking

Posted
  • Author
Posted

Blackbox & GTRPSI thanks for the inputs.

By the sounds of it the plazmaman plenum seems to win in this situation now to find one for a neo at a good price ?

ps anyone with more info please throw your 2c in here

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

    • GTSBoy
      Unknown sound similar to BOV on positive boost with partial throttle RB26

      By GTSBoy · Posted

      I don't think the shuffle can damage the turbos. It only happens at low shaft speeds and loads. It's just annoying (to some people - others are tickled by the effect) and it quite possibly reduces spool performance a little bit.
    • Murray_Calavera
      Steps to DIY sanding car back ready for respray....

      By Murray_Calavera · Posted

      Oh dear. The panel beating needs to be done before the filler work. Do you have a photo of the dent before you started? Hard enough to not flex and only hit the high spots?  What do you mean it was just temporary? 
    • Manur33
      Vag Coil Diy loom wire guage selection

      By Manur33 · Posted

      Can u check this way it works for power supply?
    • Manur33
      Vag Coil Diy loom wire guage selection

      By Manur33 · Posted

      These coils draw 10amps that what i read online
    • nouveau_poor
      Unknown sound similar to BOV on positive boost with partial throttle RB26

      By nouveau_poor · Posted

      I appreciate the detailed explanation, think I understand now. I spent the better part of last night reading what I could about shuffle and potential solutions. I had replaced the OEM twin turbo pipe with an alternate Y pipe that is separated further away from the turbo. The current one is from HKS and I had a previous pipe that was separated even further away, both have shuffle. I had heard that a divider can be welded in to the OEM pipe to remove turbulence, and figure that aftermarket pipes that are more separated would achieve the same thing. From what I read, most people with -10 turbos get shuffle due to their size, though it's a bit less common with -5s on a standard RB26. I think Nismoid mentioned somewhere it's because OEM recirculation piping is common in Australia with -5 cars. It seems that the recommendation tends to vary between a few options, which I've ordered in what I think is most feasible for me:  1. Retune the MAP or boost controller to try to eliminate shuffle 2. Install OEM recirculation piping 3. Something called a 'balance pipe' welded onto the exhaust manifolds. I don't know if kits for this are available, seems like pure fabrication work 4. simply go single turbo My current layout is as follows: Garrett 2860 -5s HKS Racing Suction intake MAF delete pipes HKS racing chamber intake piping hard intercooler piping,  ARC intercooler HKS SSQV BOV and pipe Haltech 2500 elite ECU and boost solenoid/controller HPI dump pipes OEM exhaust manifolds HKS VCAM step 1 and supporting head modifications Built 2.6 bottom end All OEM recirculation piping was removed, relevant areas sealed off I'll keep an eye out for any alternative solutions but can get started with this.  Only other question is, does shuffle harm the turbo (or anything else)? It seems like some people say your turbo shafts will explode because of the opposing forces after a while and others say they just live with it and adjust their pedal foot accordingly. 
×
×
  • Create New...