Manifold Insulators

[PM-R33]

Exactly right, if the manifold is off, chuck one of these on. I was going to do it but needed a full VRS gasket kit so didn't want to spend the extra money on another intake manifold gasket.

I definetely wouldn't go changing the gasket just on its own for the benefit of using one of these.

[Wheezy]

Chucked one of these on after seeing them at Gizzmo and speaking to URAS. Was while I was fitting my FF plenum on my 20. Not 100% convinced they will make a real world difference to me, but my plenum is fairly cool to touch after dyno runs \ a few laps on a track compared to other Plenums I have touched on an RB.

If you can get it cheaper than a genuine Nissan gasket then I would say its a "why not give it a go" while the intake is off, it cant hurt to give it a go.

[Cjmartz2k]

i would imagine a bit of effort to ensure you have a better cold air intake would negate any gains from this

given its probably a no brander china ching chong ebay part its probably rubbish

Wow, that is one of the most obtuse statements I've ever seen you type Paul. Not to typical of you, but typical of the attitude on this board towards anything that doesn't have an HKS/Greddy/Tomei sticker slapped on it. Besides, it's a freaking solid chunk of plastic (or whatever it's made out of). It's not THAT hard to make correctly for shit sakes. Use your head before you nut swing from name brand parts so hard.

About the actual effectiveness of these spacers, not just the honda boys (and I choose my words carefully) use them. They are pretty popular with the mustang guys stateside also. Anything that helps heat soak is good in my opinion, but the degree to which it helps, I couldn't being anything factual to the argument. Actaully, maybe one thing. On my jeep (4.6L straight six stroker), I will always run a couple mph slower after several back to back 1/8 runs and it heat soaks. Sticking a bag of ice on the intake for 10 minutes or so and I always run my best times with best e.t.'s by a couple mph. The mustang guys also have documented gains icing down their intakes. Granted, this isn't the same amount of temperature change. How much gain would be enough in your mind to make it worth $80? People spend a lot more and stuff that does a lot less every day.

Edited October 7, 2009 by Cjmartz2k

[juggernaut1]

Taken from outlawengineering.com.

Notice the trend that the hp and torque diminishes as rpm increases supports my previous suggestion that the spacers are most beneficial in street cars. As rpm rises and air speed through the manifold increases and the potential for the air to grab heat is reduced - the two graphs merge. Its at low/mid rpm and stop/start traffic that they will be most beneficial when the air speed through the plenum is lowish and more susceptable to heat soak.

Edited October 7, 2009 by juggernaut1

[Dorifta]

nice research, seems pretty logical

[R31Nismoid]

It'd still be good to see some data on a skyline that does not have exhaust manifolds below the plenum like the k-series.

No doubt that would be adding heat, especially as it is at the rear of the motor where airflow could also possibly be lower and so on.

Plus you are not talking about forced induction still, id be fairly certain that would have a degree of factor be it good OR bad.

Either way, your talking 12-15hp there, on a % basis, nothing noticeable in the real world to any great lengths.

[FineLine]

Dunno bout you Ash but I'll take all the 10/15 hp for 80 buck mods I can find.

[Wheezy]

It'd still be good to see some data on a skyline that does not have exhaust manifolds below the plenum like the k-series.

No doubt that would be adding heat, especially as it is at the rear of the motor where airflow could also possibly be lower and so on.

Plus you are not talking about forced induction still, id be fairly certain that would have a degree of factor be it good OR bad.

Either way, your talking 12-15hp there, on a % basis, nothing noticeable in the real world to any great lengths.

More than happy to compare mine against any RB in VIC for arguments sake....Lets see if we can get some facts for once for the sake of both sides of the argument.

Bring it on I say

[R31Nismoid]

Dunno bout you Ash but I'll take all the 10/15 hp for 80 buck mods I can find.

Well its not $80 buy the time you have it fitted if you cannot DIY

Probably closer to $400, then the removal of the water lines going to the plenum etc etc, its not longer a $80 adventure

[FineLine]

Well its not $80 buy the time you have it fitted if you cannot DIY

Probably closer to $400, then the removal of the water lines going to the plenum etc etc, its not longer a $80 adventure

c,mon fessup Ash. The black knight is in your ancestry isnt he.

[Wheezy]

I pity the fool who cant remove an RB plenum...$20 set of tools from super crap would be enough to do the job.......and don't give me that torque wrench crap

Happy to do a test with some one after I get back from Tokyo at the end of the month

Could possibly organise this at Status (I will be there for some data logging tuning soon anyway). I'm sure if time permits Trent would be up for it. (Not putting words in his mouth or anything)

[R31Nismoid]

c,mon fessup Ash. The black knight is in your ancestry isnt he.

lol

I pity the fool who cant remove an RB plenum...$20 set of tools from super crap would be enough to do the job.......and don't give me that torque wrench crap

Happy to do a test with some one after I get back from Tokyo at the end of the month

Could possibly organise this at Status (I will be there for some data logging tuning soon anyway). I'm sure if time permits Trent would be up for it. (Not putting words in his mouth or anything)

Well two different cars = no good.

So - I'll put this out there, being i am a good sport.

If dorifta wants to be the guinea cop for this and...

1. Pay for the gasket himself/install

2. Have it dyno'd before and after the install (on the same day)

3. Set it up to measure intake temps before and after install

Then i'll pay the dyno fee's.

It's gotta be Status, Racepace, RE customs or Dr Drifts though, that is the requirement there.

[Wheezy]

Happy to take my manifold off. Think I have it down to an art now.

Otherwise dorifta can go for his life.

[gotRICE?]

Taken from outlawengineering.com.

Notice the trend that the hp and torque diminishes as rpm increases supports my previous suggestion that the spacers are most beneficial in street cars. As rpm rises and air speed through the manifold increases and the potential for the air to grab heat is reduced - the two graphs merge. Its at low/mid rpm and stop/start traffic that they will be most beneficial when the air speed through the plenum is lowish and more susceptable to heat soak.

I think its good that you are taking the time to research, but you keep making the comment about it being most beneficial in traffic.. WHY would it matter if you made an extra 10% of power sitting in traffic?

[XRATED]

I emailed the manufacturer:

"Dear mace_engineering_group,

Is there any plan to manufacture these for rb26?

I'm shure you guys have done your testing, but there are coolant passages that run through the rb25 manifold... thus the manifold temps will stay close to the coolant temp.

The rb26 intake manifold dose not have any coolant passages so your product may yield better results.

Just an oversilmplified observation.

Cheers

Justin"

"Dear xratedgtr,

Would love to, however we have a lot of other engineering developments on the go plus we're down and engineer

The main reason why these spacers work is that they lengthen the runners and not so much from a cooling perspective (though it certainly does help), which is why they still work well on RB25's

In saying this though I'll put you on the interest list.

Kindest Regards,

Steve"

Take from that what you will...

[juggernaut1]

I think its good that you are taking the time to research, but you keep making the comment about it being most beneficial in traffic.. WHY would it matter if you made an extra 10% of power sitting in traffic?

I like better mid range and throttle response in the rpm range where 90% of my driving is done.....particularly when bigger turbo's are fitted. Area under the curve is more important to me than peak hp. But hey I'll take both mid range and peak hp if I can get them.

I run one of these spacers on my SR....and on a 36 degree day after 42 dyno pulls the intake manifold was only warm to touch. A side benefit is that the fuel rail also gets less heated (as heat transfer from the intake manifold is reduced or at least delayed) so your fuel temps would also be cooler.

I didn't do a before and after test because a myriad of other changes had also been made so I can't quantify any specific gains (or losses).

At the end of the day the cost of the spacer was insignificant compared to what else had been spent on the car - there were no apparent downsides that I could see - so I installed one.

I even contemplated stacking two together however, my studs weren't long enough and the intake side of things was getting tight in the engine bay as well even if I changed my studs.

It may only be minor percentage gain....but if you can couple that with other minor mods you may just end up with a noticeable difference in the end.

[juggernaut1]

The main reason why these spacers work is that they lengthen the runners and not so much from a cooling perspective (though it certainly does help), which is why they still work well on RB25's

In saying this though I'll put you on the interest list.

Kindest Regards,

Steve"

Take from that what you will...

I've thought of the change in runner length too. However, wouldn't manufactures have lengthened the runners by the thickness of the spacers (ie. around 3 - 5 mm) if the gains were attributed to just solely the change in runner length?

[gotRICE?]

Not necessarily, as the manufacturers arent always making cars to squeeze every last ounce of power out of them.

[juggernaut1]

Not necessarily, as the manufacturers arent always making cars to squeeze every last ounce of power out of them.

True, but they are trying to make engines more efficient. Longer runners = more torque in the rpm range where most people drive. More torque = more efficent engine.

Longer runners = less peak hp as a generalisation.

[STATUS]

They are a 6mm intake manifold spacer designed to reduce heat transfer between engine intake ports and the intake manifold. Hence, reducing intake air temperature.. Wondering if anyone has used them or tested them. AFTER OPINIONS TOO. They can be found at ebay,, not sure where else they stock them

been using them for years (gizzmo) search phenolic on here i think i posted up datalogs a long while back. Every SR20, CA18 and RB we build has one fitted. GTR's and rb30's love them.

The inlet temp logs will prove any nay sayers wrong..