Jump to content
SAU Community

Recommended Posts

So I've noticed on eBay there's a few greddy 6 throttle body's intake plenum replicas on ebay, now the greddy is around the $1100 mark and the eBay jobs are around $300 to $500 but still boast of decent power gains. Has anyone brought a eBay special and noticed the gains with there rb26? Or had any troubles with them?Or is it best to stay with the original intake?

Link to comment
https://www.sau.com.au/forums/topic/444211-ebay-plenum-for-rb26/
Share on other sites

Who's to say the Ebay one won't also?

Have you checked this theory by measuring the egt's in each runner, or are you just happy to quote old wives tales? Gibson didn't have any trouble with it afaik...

I'm just asking questions to find out if it's worth while or not. I'm no mechanic and trying to find these things out on google is hard if not to no answer at all. That's why I've tyres to the forum to hopefully find someone that has done this and that may help me out

People do all kinds of stupid things, that doesn't mean you should copy them... :P

I have seen 500kw through a factory setup, intercooler, plenum, manifolds, piping, airbox, fuel lines etc. If you are near that I would be more worried about the block splitting than the runner flow. Just run a fat mixture and cram some more boost in.

Just to help the OP, ive got a genuine Greddy and had a ebay/china copy side by side.

You had to look really hard to spot the differences, runners, diameters, everything identical, slight differences in casting lines...very slight.

Would come down to the quality of the alloy IMHO.

Ive met and spoken with a Chinese manufacturer that makes them, as he said to me with any part, supply me with the brand name original and ill copy it for a fraction of the price and you wont tell the difference.

And just to throw a spanner into the works, he was offering them to me for $US 80 dollars each 2-3 years ago, no wonder there are so many copies out there......

Would come down to the quality of the alloy IMHO.

This... And how it's actually made. You can have the same materials, same design (making a mould isn't hard) and still stuff it up by having the casting temperatures or cooling speed all wrong. End up with a brittle part of the product which will be the first to crack under a high load.

Personally, I wouldn't want anything potentially breaking off a scraggy bit of metal under high temp / pressure and going straight into my engine. So if you go for a cheap copy get it checked out with a scope and cleaned up before it goes near the car.

  • Like 1

I found a few forums searches off google saying that they lean number 6 , thought I'd ask before I finished my motor because it would be easier to change a manifold whilst it's out. I'm thinking I might buy the greddy/trust manifold for peice of mind

Re cylinder 6 - true. Although tuned around.

Stock plenum is awesome and you will have no issues so keep it. Don't waste your money on these for the RB26

In my opinion the best is the Nismo Plenum - max 2-4% improvement - EDITED: 1-2% power and 0.4% fuel saving - SUBJECTIVE. Yes I have one

At $1500-$2000 money is spent better elsewhere.

Topic covered heaps already

Edited by Sinista32
  • Like 1

I'm building my motor ATM to have around 450 to 500kw

I found a few forums searches off google saying that they lean number 6 , thought I'd ask before I finished my motor because it would be easier to change a manifold whilst it's out. I'm thinking I might buy the greddy/trust manifold for peice of mind

I see.

Well I'd double check with Racepace, just give them a call to confirm.

As I have said before, you can get decent power gains with the stock Inlet Plenum but how much to what point, I'd double check.

So yeah, don't go throwing your money on ebay parts.

I noticed your user name and that you had a R32 GTR, so im assuming your doing a RB30 bottom end?

If so, before you go any further, the Greddy plenum will hit your clutch master, there are work arounds, or a few ways to do it but if your only going to 500Kw you may as well stay with the factory item, it does still work well.

Yes 6 can lean out, or run leaner, quick cheap way is get your injectors flow tested and put the highest flowing one on number 6. ;)

Otherwise 6 EGT probes on the manifold will do the trick......as will getting the tuner to run injector 6 a little longer.

Edited by GTRPSI
  • Like 1

Yeah mate I'm halfway through building a 26/30. Can the stock manifold be port match to the head or is it already done from factory? Also is there threads on how to fix the greddy manifold with the clutch master cylinder touching?

There are a few threads, all with different suggestions/methods in the RB30 section.

From using spacers under the cross member to steering shaft spacers to cutting the bonnet, some even remove the clutch booster and use a different clutch slave with spacer.

We are doing the same build right now for our 26/30 R32 GTR.

Edit, Forgot to add, port matching always helps, all depends on how far you are going or are prepared to look at details.

Edited by GTRPSI
  • Like 1

I've had the 30 bottom end in my GTR before but I never went crazy on the head. My n1 pump let go so I'm spending abit more this time. But all I did was cut the inner braces out of the bonnet and tapped the floor up abit with a hammer near the low mount dumps for clearance. Everything else was sweet. Well I've got an aluminium die grinder bit so I better port match it

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


  • Similar Content

  • Latest Posts

    • Update 3: Hi all It's been a while. Quite a lot of things happened in the meantime, among other things the car is (almost) back together and ready to be started again. Things that I fixed or changed: Full turbo removal, fitting back the OEM turbo oil hardlines. Had to do quite a bit of research and parts shopping to get every last piece that I need and make it work with the GT2860 turbos, but it does work and is not hard to do. Proves that the previous owner(s) just did not want to. While I was there I set the preload for the wastegates to 0,9bar to hopefully make it easier for the tuner to hit the 370hp I need for the legal inspections that will follow later on. Boost can always go up if necessary. Fitted a AN10 line from the catch can to the intake hose to make the catchcan and hopefully the cam covers a slight vacuum to have less restrictive oil returns from the head and not have mud build up as harshly in the lines and catch can. Removed the entire front interior just shy of the dashboard itself to clean up some of the absolutely horrendous wiring, (hopefully) fix the bumpy tacho and put in LED bulbs while I was there. Also put in bulbs where there was none before, like the airbag one. I also used that chance to remove the LED rpm gauge on the steering column, which was also wired in absolute horror show fashion. Moved the 4in1 Prosport gauge from sitting in front of the OEM oil pressure gauge to the center console vents, I used a 3D printed vent piece to hold that gauge there. The HKB steering wheel boss was likely on incorrectly as I sometimes noticed the indicator reset being uneven for left vs. right. In the meantime also installed an airbag delete resistor, as one should. Installed Cube Speed premium short shifter. Feels pretty nice, hope it'll work great too when I actually get to drive. Also put on a fancy Dragon Ball shift knob, cause why not. My buddy was kind enough to weld the rust hole in the back, it was basically rusted through in the lowermost corner of the passenger side trunk area where the wheel arch, trunk panel and rear quarter all meet. Obviously there is still a lot of crustiness in various areas but as long as it's not rusted out I'll just treat and isolate the corrosion and pretend it's not there. Also had to put down a new ground wire for the rear subframe as the original one was BARELY there. Probably a bit controversial depending on who you ask about this... but I ended up just covering the crack in the side of the engine block, the one above the oil feed, with JB Weld. I used a generous amount and roughed up the whole area with a Dremel before, so I hope this will hold the coolant where it should be for the foreseeable future. Did a cam cover gasket job as the half moons were a bit leaky, and there too one could see the people who worked on this car before me were absolute tools. The same half moons were probably used like 3 times without even cleaning the old RTV off. Dremeled out the inside of the flange where the turbine housing mates onto the exhaust manifolds so the diameter matches, as the OEM exhaust manifolds are even narrower than the turbine housings as we all know. Even if this doesn't do much, I had them out anyways, so can't harm. Ideally one would port-match both the turbo and the manifold to the gasket size but I really didn't feel up to disassembling the turbine housings. Wrapped turbo outlet dumps in heat wrap band. Will do the frontpipe again as well as now the oil leak which promted me to tear apart half the engine in the first place is hopefully fixed. Fitted an ATI super damper to get rid of the worn old harmonic balancer. Surely one of the easiest and most worth to do mods. But torquing that ARP bolt to spec was a bitch without being able to lock the flywheel. Did some minor adjustments in the ECU tables to change some things I didn't like, like the launch control that was ALWAYS active. Treated rusty spots and surface corrosion on places I could get to and on many spots under the car, not pretty or ideal but good enough for now. Removed the N1 rear spats and the carbon surrounding for the tailpipe to put them back on with new adhesive as the old one was lifting in many spots, not pretty. Took out the passenger rear lamp housing... what do you know. Amateur work screwed me again here as they were glued in hard and removing it took a lot of force, so I broke one of the housing bolts off. And when removing the adhesive from the chassis the paint came right off too. Thankfully all the damaged area won't be visible later, but whoever did the very limited bodywork on this car needs to have their limbs chopped off piece by piece.   Quite a list if I do say so myself, but a lot of time was spent just discovering new shit that is wrong with the car and finding a solution or parts to fix it. My last problem that I now have the headache of dealing with is that the exhaust studs on the turbo outlets are M10x1.25 threaded, but the previous owner already put on regular M10 nuts so the threads are... weird. I only found this out the hard way. So now I will just try if I can in any way fit the front pipe regardless, if not I'll have to redo the studs with the turbos installed. Lesson learned for the future: Redo ALL studs you put your hands on, especially if they are old and the previous owners were inept maniacs. Thanks for reading if you did, will update when the engine runs again. Hope nothing breaks or leaks and I can do a test drive.
    • No those pads are DBA too  but they have colors too. I look at the and imo the green "street" are the best.
    • I’m not sure what happened I told them about sonic tunes free OTS tune and the next the I know .. I was booted..   To funny 
    • Yea - I mean I've seen my fuel pump which is decades old and uh, while I'm not saying this with real knowledge... but I sure get the ick at using anything in the fuel system that produced the state of that pump. Many years ago I went through multiple pumps (and strainers) before I dropped the tank to clean it out with extreme violence. I'm talking the car would do maybe 50km before coming to a halt, which resulted in me cleaning out the filter with some brake cleaner and going on my way. None of my stuff ever looked like what came out of your fuel tank. I don't think I'd be happy with it unless every single component was replaced (or at least checked/cleaned/confirmed to be clean here).
    • I'm not going to recommend an EBC pad. I don't like them. Just about anything else would suit me better. I've been using Intima pads for a while now.
×
×
  • Create New...