Jump to content
SAU Community

Larger Throttle Body

Get EPIC

By Get EPIC,
in Engines & Forced Induction

 Share

Recommended Posts

Get EPIC Rising Star

Get EPIC

Posted
Posted

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
R31Nismoid Grand Master

R31Nismoid

Posted
Posted

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.

PM-R33 Grand Master

PM-R33

Posted
Posted

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...
Ryno Experienced

Ryno

Posted
Posted

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.

r33cruiser Grand Master

r33cruiser

Posted
Posted

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

T04GTR Grand Master

T04GTR

Posted
Posted

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.

WARLORD Veteran

WARLORD

Posted
Posted (edited)

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
TiTAN Grand Master

TiTAN

Posted
Posted (edited)

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
T04GTR Grand Master

T04GTR

Posted
Posted
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...

WARLORD Veteran

WARLORD

Posted
Posted

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • GTSBoy
      New kid on the block

      By GTSBoy · Posted

      The wiring diagram for the R33 RB25 is freely available, and is essentially the same same as most other RBs (just with differences as to which pin # does which job). To get the ECU to power up, you just need to provide power to the ECCS relay, and have the other power feeds that come in from the top left of the wiring diagram (wrt the ECU) that give perma power to the fuel pump relay, the ECU itself, etc etc, all connected. When you put power on all these it will just come to life. It's pretty clear from the diagram what needs to happen. Just follow the lines from the 12V + supply stuff in the top left over towards the ECU. I've even posted snips of such diagrams (not for vanilla 25, I think for Neo and 26) to various threads here in the last few months, talking about what it takes to get the fuel pump and FPCM up and going. Search these up and they will help get you started on doing the same with the vanilla 25 diagram. Hell, for all I know, I've done the same with that one in years past and have forgotten.
    • Duncan
      New kid on the block

      By Duncan · Posted

      Yep...so unless someone posts up the answer you will need to probe from the ECU connector to the dash plug with a multi meter in continuity mode to trace the wires.  Note the ECU has multiple - and + (and across different key settings - Battery, IGN and Start) and most likely the power is fed from the connector(s) that is normally near the left hand headlight.
    • Songo
      New kid on the block

      By Songo · Posted

      Thanks Duncan, I am actually just trying to get the Rb turning and running with the RB25DET S2 original loom itself  I am just trying to get it going outside the body and not thinking about the S15 or trying to match anything to the S15 loom at all I am only trying to see if anyone has done this and what pin they found to be the ignition trigger and ECU+/- on the dash connector, that's about it. Thanks  
    • iain_ST44GA
      M35 VQ25DET starter motor

      By iain_ST44GA · Posted

      Hi Guys, Does anyone know any aftermarket part numbers for a starter motor to suit the VQ25DET? I can find lots of alternative part number for the VQ35DE, which I assume would fit, but there is a lot of conflicting information out there. Thanks..
    • Murray_Calavera
      R33 GTR running -9 with no tune

      By Murray_Calavera · Posted

      I don't understand how this hasn't boiled down to - Upgrade the turbo when you have everything required. ECU, injectors, fuel pump, turbo, etc. Do it all at once.  If you don't have everything required, just enjoy the car as it is and keep saving up your pennies. 
×
×
  • Create New...