Jump to content
SAU Community

Recommended Posts

Hi all,i am about to get a forward facing plenum installed on my R33.It has an adapter plate to fit the standard throttle body but i am considering going a 80mm TB.Would this have any gains with a stock series 2 turbo or only when putting a larger turbo on?

Link to comment
https://www.sau.com.au/forums/topic/291471-larger-throttle-body/
Share on other sites

There is no gain upgrading the T/B.

The only thing you get is less throttle control, i do not rate that as a gain.

Few people around here have actually put the factory one back on because larger TB's are too "on/off" in low throttle applications.

Ok if you are drag racing, but daily driving etc, no no.

Bit of a controversial subject on turbo cars, every one has a different opinion, not many people do back to back tests. I posted up the atricle from Autosalon a while back, ill try and find it.

Here it is in Nick's thread. Half way down. http://www.skylinesaustralia.com/forums/Mo...html&st=180

I'm going to change mine over to the plazmaman one when i get around to it one day to match the plenum.

  • 3 months later...

I run an 80mm throttle body and really like it as far as drivability goes. You probably don't quite have the same control at low throttle, but I wouldn't say it is on or off. It only took me a drive or two and it felt as natural as when driving with the stock one.

What is cool, is that you will find it easier to blip the throttle when down shifting, as you don't need to stab as much of the throttle (with your heel) when compared to stock, to get the revs up.

As for performance, there is probably very little gain, but I don't regret the purchase and wouldn't go back to the stock one.

Cool. I just didnt want to re-bore my plenum (still stock sized opening) as i cant with the position that the hole is in.

^^ I hope you bored your's out to 80mm. Seen ppl claim to gain hp with 100mm t/b's but still have the stock 65mm opening in the intake plenum LOLZ

the only gain is if the plenum has a shit distribution. but you loose low speed response. if you do get a gain its because the plenum is not great.

if you have a look at alot of the older turbo race cars all have no bigger than 75mm. (same size as the pipework.)

1400hp 4cyl with a smaller than 3" tb says alot.

just dont put one thats bigger than the plumbing. complete waste of time.

75mm is big as youl ever need. ever.

ive got one love it,

i have no problem with control,

if you going the hole hog on a set up than do it,

thats my opinion.

most gtrs that go singal t/b use a 90mm,if there was no diference why do the use them an not a 75mm one ??

Edited by WARLORD

There is the ease of tuning with a map based ECU when its single TB instead of multiple, which may have had something to do with it also.

I like my Q45 TB, yes it is a little different to drive with than the stock TB as you don't have to be on the throttle that much to get it moving but it hasn't made the car annoying to drive around town. Investing in a clutch that doesn't require super human leg muscles to operate will go further towards making it nice to drive everyday than a smaller TB.

Edited by TiTAN
ive got one love it,

i have no problem with control,

if you going the hole hog on a set up than do it,

thats my opinion.

most gtrs that go singal t/b use a 90mm,if there was no diference why do the use them an not a 75mm one ??

because having a larger one slows the air velocity down stopping the last couple of cylinders getting more air that the front few, giving a more evan distribution.

like i said. if the plenum is not a great design then gains will be had. but at the cost of low load drivability. not a big loss but a loss.

put a flamin mongrel clutch in and it will show its head very fast.

the same reason its good to put a centre fuel feed in a fuel rail once your got a really big fuel pump,it slows the fuel flow down in the rail so each injector has time to grab the same amount of fuel along the length of the rail...

there will be no gain installing a larger throttle body than the piping.

oh and that on a gtr the plenum is already 80mm to begin with...

and a greddy plenum would be bigger again,

that's what i meant by the hole hog,hopefully soon when my dam exhaust manifold is finished i can show that having all not some of supporting mods from A-Z all together makes for a good package.

well that's the idea

as for a o/s t/b on a stock plenum and stock turbo and so on,yes its a waste of time.

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).
×
×
  • Create New...