Need Facts On Front Facing Plenums

[FordyR31]

Hi guys,

I have seached, googled and read lots about this and know that the Greddy, Hypertune, CPC and Plasmaman are the best and expensive. What I want to know is, are any of the cheaper options actually any good? I have read that some leak coolant, some just don't fit right and end up costing more to buy and fit than a more expensive one. Has anyone had any bolt on success with a "Freddy" plenum on an RB25 S2? I am not chasing massive power, 250ish rwkw, I simply want a cleaner looking engine bay, easier to service and my standard plenum has issues. The top rad hose connection has rusted away and isnt clamping properly. I have also searched a simple fix for this problem, asked questions in similar topic threads and come up with nothing. If anyone has bought a decent cheaper one or has good advice I'm all ears on cost, where you bought it, how easy/difficult it ended up being for the installer and tuning results.

Thank you for your patience, even a good link would be great as I'm sure its a common question. Just can't find the answers I am looking for.

Edited August 15, 2013 by FordyR31

[GTSBoy]

It's a dead common question that has been fanboid to death on here even just in the last few weeks.

in short, they are a waste of time, particularly if you are only going to stay near stock power levels (and yes, I include 250rwkW in that range). There's a lot of headf**k involved in fitting them, cost to do so, new pipework, etc etc. All for the dubious advantage of it being "neater".

The stock plenum works fine. The FFPs offer very litte to no advantage, and the Greddy/Freddy ones actually cost low/mid torque. Unless they were to offer a significant gain in the top end, this would be an unsupportable position just on that basis.

The only decent reason to fit one is if you are going for massive power, therefore needing a bigger plenum and having a massive top mount turbo that makes it difficult to get the pipework back to the TB. Otherwise, man up and remove a few 10mm fasteners to expose the spark plugs every three years or so when you swap them out.

[Josh080691]

Spark plug changes every 3 years? Hate to be your car :// mine usually gets done 6 months or less^^ $20 for new plugs won't break the bank.

[Soundboyracer]

I change my plugs once a year. Then again I don't drive it much

[KiwiRS4T]

I think OP has decided to get one and wants to know how much to spend. I have a cheap Chinese Greddy copy and it works fine - just needed an adapter so I could fit my stock Throttle body (no need to pay for an aftermarket 80mm item).

If you buy a cheap one then before you fit it check the mounting face and pressure test it. Some have pinholes in the casting (chrome plating will generally take care of that but I'm too cheap for chrome plating).

[FordyR31]

Thank you for not flaming guys. It has been concluded that the plenum needs to be changed regardless of wheather its for another stock one or for an after market one. I had read the pro's and cons power wise and heard of the loss of midrange which is a con I don't want. I tend to service the car every six months even though it hardly gets driven anymore. I have had the car since 2005 and it is just a pain taking it all apart to change six plugs. If there is an easy way to fix my standard plenum I'm keen to know but if welding is involved, it looks like a tight fit and that again, the standard one would need to come off. If it was a simple case of I want it just because, I would save for a more expensive one but every time I drive the car just to keep it in driving condition I am expecting the top rad hose clamp to give way and lose all the coolant. Obviously this is also holding me back from track days and wednesday night drags at Eastern Creek which I would like yo start doing more regularly. KiwiRS4T which one did you buy, how much was it and where did you get it from?

Thanks again.

Edited August 15, 2013 by FordyR31

[GTSBoy]

Spark plug changes every 3 years? Hate to be your car :// mine usually gets done 6 months or less^^ $20 for new plugs won't break the bank.

I had my RB20 for 12 years. In that time it got a set of new plugs when I bought it, and a set probably halfway through the 12 years. When the first set came out (halfway through) they were still fine. We only changed them because it was getting a boost up and going on the dyno.

There is a lot of unnecessary plug changing advocated on this forum. I usually just sit back and let it happen, because I don't care that much.

[zebra]

I only change mine when it needs it

[FordyR31]

For $30 I'm happy to do it every 6 months. Each to their own but it isn't a thread about changing plugs. Got some info so far but would like to know which Plenums to stay right away from and which are ok to buy, easy to fit up etc etc. I would be having it professionally installed so trying to minimise all extra costs.

[KiwiRS4T]

Thank you for not flaming guys. It has been concluded that the plenum needs to be changed regardless of wheather its for another stock one or for an after market one. I had read the pro's and cons power wise and heard of the loss of midrange which is a con I don't want. I tend to service the car every six months even though it hardly gets driven anymore. I have had the car since 2005 and it is just a pain taking it all apart to change six plugs. If there is an easy way to fix my standard plenum I'm keen to know but if welding is involved, it looks like a tight fit and that again, the standard one would need to come off. If it was a simple case of I want it just because, I would save for a more expensive one but every time I drive the car just to keep it in driving condition I am expecting the top rad hose clamp to give way and lose all the coolant. Obviously this is also holding me back from track days and wednesday night drags at Eastern Creek which I would like yo start doing more regularly. KiwiRS4T which one did you buy, how much was it and where did you get it from?

Thanks again.

I bought mine from Luxury Sports

http://www.trademe.co.nz/stores/luxury-sports/contact

for $330 although they are out of stock atm and new price will be $380

It looks very similar to this one:

http://scarles.co.nz/shop-online/cooling-products/intake-manifolds/intake-manifold-front-face-rb25

[FordyR31]

Scarles have an Aus online shop I just found I just found out. The plenums look ok and are rediculously cheap! It has said it takes their fuel rail but I'm assuking from your first post that a stock fuel rail isn't a problem? As long as its only a plenum and adaptor needed one of these may be the go.

Thanks.

[XRATED]

I had my RB20 for 12 years. In that time it got a set of new plugs when I bought it, and a set probably halfway through the 12 years. When the first set came out (halfway through) they were still fine. We only changed them because it was getting a boost up and going on the dyno.

There is a lot of unnecessary plug changing advocated on this forum. I usually just sit back and let it happen, because I don't care that much.

Well a fresh set of plugs are worth 12-18kw on the dyno to me... So I change them after every drag day/track day.

6 years is longer than even the factory recomendations.

[GTSBoy]

No it's not. Platinum plugs, 100000km.

[XRATED]

Not the engine manuafuturer, the plug manufacturer. Sould have been more clear.

NGK copper plugs are reccomended service life of 10 to 20k miles...

Platnium... sure if it's a factory engine.

At the end of the day, most people here don't have factory tuned engines (engines that are not modified). As the hp increases so does the requirment to service the engine more frequently. Including spark plugs.

I will agree the the factory cross over pipe is a PITA but I try and keep the factory intake manifold on my rb's as long as I can.

[KiwiRS4T]

Yep stock side feed rail (it will take a top feed rail if you want to change later) and side feed 550 injectors. BTW my tuner has told me to change to platinums so I have PFR7G now.

Scarles have an Aus online shop I just found I just found out. The plenums look ok and are rediculously cheap! It has said it takes their fuel rail but I'm assuking from your first post that a stock fuel rail isn't a problem? As long as its only a plenum and adaptor needed one of these may be the go.

Thanks.

[FBRacing]

I have a S1 with the Greddy manifold with KU engineering TB. It accepts stock fuel rail which I still have but upgraded to 750 injectors. No leaks, problems, or fights. You do lose your windshield wiper fluid tank for the piping to go thru the sheet metal. I have 3 3/4 inch piping running to it from the FMIC. I wouldn't go with it unless you build the head with cams, a turbo that can put out pass 12 psi, and a fuel/ecu management system that can handle. A buddy has one on his stock S2 RB25 and it took away a lot of mid but top end greatly improved sort of. It felt around 5000ish RPM it started dropping out. Maybe the turbo was max'n out. The Greddy style intakes are much larger in volume so it takes a bit longer for that snail to fill it up. I don't know. I guess research it more. There's gotta be a lot of guys running them.

[FordyR31]

Thanks. It seems most of the Greddy copies are fine. Only have 2.5 inch piping and a GT3076 running up to 18psi on high boost. In the process of sorting one with a larger throttle body. I did get excited when i saw that Nungun had Greddy ones for $860ish but then it blew out to around 1100 with throttle body adaptor and shipping. Still cheaper than the ebay stores I found.

[KiwiRS4T]

Why do you want a larger throttle body? Stock one will be fine. My adapter was $20 or you could make one.

Thanks. It seems most of the Greddy copies are fine. Only have 2.5 inch piping and a GT3076 running up to 18psi on high boost. In the process of sorting one with a larger throttle body.

[FordyR31]

Found a great thread from 2 years ago. I do want drivability and the stock throttle body is larger in diameter than my cooler piping anyway. Don't think there is much happening in the way of pressure drop and will get sub 300rwkw. Adaptor plate it is if needed.

[KiwiRS4T]

Here's a local supplier:

http://www.ebay.com/itm/New-Nissan-Skyline-R33-ELECTROPLATED-Plenum-w-Original-Throttle-Body-Adapter-/171082227375?pt=AU_Car_Parts_Accessories&hash=item27d54b9eaf

Found a great thread from 2 years ago. I do want drivability and the stock throttle body is larger in diameter than my cooler piping anyway. Don't think there is much happening in the way of pressure drop and will get sub 300rwkw. Adaptor plate it is if needed.