RB30 Throttle body?

[Justlikemusic 0]

I measured up an RB30 Nissan throttle body today and it seems like its a pretty decent fit if there is a bit of mucking around. I can see that the AFM is pretty decent size, compared to the 325eta throttle body. I can plough out the intake manifold a bit. I'm sure a bigger TB on the eta will make a massive difference. The redline isnt much of a problem I feel after 4200rpm or so it just loses any power so redline isnt making much difference at this stage I think. There is massive amounts of torque compared to the general range of power at about 2600rpm.. and this drops off near 4. Im sure its the cam/head etc, but larger TB should make more power higher in the rpm.

Thoughts?

[hybrid 1039]

interesting mod if you make it work go for it..

.. you may have a few followers if you pull it off!

[Justlikemusic 0]

Well it measures up to the AFM sorta. I have taken them off the car and measured them side by side with a ruler. Ill go buy one next week and try fit it up next weekend. Maybe if I can get some funds this week Ill do it on the weekend. Ill see what happens.

*Edit: Found searching "...e36 M motors had their throttle body opening at 63.5 mm" Some specs on 325e and 325i TB sizes would be good.

RB30E breathes through a 55mm throttle bore

EA Falcon 3.9L 64mm throttle bore

Both of these I can get for like $20. Apparently the problem is in the intake manifold, and head... but im sure a larger TB will do some good.

Edited February 13, 2008 by Justlikemusic

[Gus 5]

I really would not bother on the eta engine..once you see the port sizes compared to the 325i Head you will understand. On a 325i maybe, however I found fitting a large TB to a cammed engine did very little. You will prob just lose some of the torque the eta was built for

good luck if you want to experiment, i really wouldnt expect too much though

[Justlikemusic 0]

Wouldn't the intake manifold have more to do with the torque etc... like the long runners for torque. The 'carby'/butterfly etc is just going to let more air flow through and with the manifold inlet ported out where the TB joins to it, and the actual TB larger, and the pipe from the TB to the AFM would obviously be upgraded to something thats the same size of the AFM. Im trying to work giving internet tech support to ppl and view forums at the same time, this is becoming an art. Getting paid for bimmer education. zzzz

Basically to expand on that a little bit... Im sure the six intake ports have a larger area than the TB area. I understand if the tb was the same size as the intake ports your engine would probably drown. But I look at the 350cfm Holley carbies that I have put on 3.3L 202's in the past and the triple webers on 2.8L nissan engines etc and start to think there could be some definate potential with increasing the size of that intake. But then I'd probably have to get the ecu to relearn (if it does that in the beemas? should do i think)

Edited February 13, 2008 by Justlikemusic

[will 169]

You can only get as much air into the engine as the valve opening will allow in a N/A engine. Unfortunately the eta motor has rather small intake ports/valves.

Has your standard TB got a TPS? If it has you will need to transfer it over to the new one if that one doesnt have one.

Give it a go, see what happens... nothing ventured, nothing gained..

Will

[Justlikemusic 0]

TB will not affect torque unless to have some other fundamental problems that were being masked.

Exactly what I thought. If I hog out the intake manifold around the TB connecting area, in theory that should open things up a bit. I mean six cylinders can take in more than what that pissy TB is allowing. It has no TPS on it from what I can remember, and just was a butterfly. This makes it really easy to upgrade. Another thing I was thinking of is linking six individual TB's on it with a megasquirt ecu. I can do that and tinker with the car, thrash the crap out of it and then when a motor rebuild is due, do it.

[Justlikemusic 0]

http://holdenpaedia.oldholden.com/images/c/c9/Carby_0.jpeg

I have two of these bases, and can buy another four for really cheap... weld on bellmouths for the front. use an intake manifold gasket and make a plate up, then weld these carb bases to them, hook up the linkage... M POWER Style. -.-

[Justlikemusic 0]

http://www.clockwisemotion.co.uk/images/ho...ttle-bodies.jpg

Another thing with customer throttle body install with megasquirt is the custom injector rail you can use, basic lack of intake manifold so you are just getting max rpm power, and larger injectors from any car you wish custom fitted into it.

http://www.mez.co.uk/dcam/DSC00232.jpg

This is making me lose sleep.

[Gus 5]

give it a go if you must, just don't expect massive gains and try and remember that the eta engine is not a performance engine by any stretch

[hybrid 1039]

3pedals .. liking this new found 08 tech stuff without the attitude .. PS .. I had 1/2 a bottle of wine.

[Justlikemusic 0]

Understood. I might try the RB30 TB though because that will increase breathing a fair bit. Is it true though that the eta TB is REALLY tiny for the engine, and the manifold for that matter too? I am just trying to reluctantly give it a bit more power without doing anything major. I got about two months before the $2000 that I paid for the car is paid off, then I can start focusing more funds into it. Engine mods will start adding up, and I want the car paid off before they do... and at the same time, 325i head with rebuilt ETA bottom end and boost will probably get it to boogy as much as I want.

[mr E34 11]

I measured up an RB30 Nissan throttle body today and it seems like its a pretty decent fit if there is a bit of mucking around. I can see that the AFM is pretty decent size, compared to the 325eta throttle body. I can plough out the intake manifold a bit. I'm sure a bigger TB on the eta will make a massive difference. The redline isnt much of a problem I feel after 4200rpm or so it just loses any power so redline isnt making much difference at this stage I think. There is massive amounts of torque compared to the general range of power at about 2600rpm.. and this drops off near 4. Im sure its the cam/head etc, but larger TB should make more power higher in the rpm.

Thoughts?

A lot of work/development time to get power from N/A. Have posted this before, check it out. Before you alter anything you need base line pwr/trq figures, tuning is an art & science.

http://www.alpinaaustralia.com.au/dyno/dyno_main.htm

[CamB 48]

Disclaimer - I don't know much about the eta.

Now we've got that out of the way, google tells me the eta makes peak power at 4250rpm - this is a camshaft, port size and valve size thing - changing the throttle body is unlikely to free anything up.

[Justlikemusic 0]

I'll be boosting the M20 shortly... and my mate has a RB30 Throttle body sitting there at his place which I'm gonna ring him in a sec to get from him. I'll be able to fit this up tomorrow hopefully if I get the time. Probably wont make much difference right now, but once the boost goes in with the 325i manifold I think things might change a little.

[Justlikemusic 0]

http://www.alpinaaustralia.com.au/dyno/dyno_E30_M20_325e.htm

Most of that 20kW's is probably from the Chip though... I do believe there is gains from a bigger TB however. Whether it be making the car feel faster, or actually making it faster, that TB thats on there from factory is really pissy.