'i' throttle body on eta

[EtaSport]

Who has done this, and what were your experiences? I know that the two are almost completely different, and to get gains you have to bore out the intake to match.

Here is my problem. My eta throttle body is pretty much waisted. The TPS is getting flooded with oil which is sending bad signals to the computer causing mixtures to be screwed up. So, I decided that I would just get an m20b25 TB and pick up a bit more response. I had the breather tube for the i TB lying around so I used that, installed the TB, hooked up the water lines, sealed all vacuum ports that I wasnt using, put my linkage on, and made a custom air boot that includes the ICV port.

Well the installation finally concluded and i fired the car up, it ran well, then idled well. It pulled a tad bit harder from the get-go, nothing astronical, but i wasnt expecting much. Now I am having idle problems, and sometimes the linkage sticks open. Also I am having fuel problems. There is too much fuel going in all together. Black smoke is coming out of the exhaust all the time, and my idle is around 1500 when i push the clutch in. I noticed that the return spring is only about half as strong as the etas, and when I force the the linkage back the idle will go down where desired. (i also have the ICV screw all the way in)

Does the ecu need to adjust? I ran it on the highway today and the mpg gauge was going crazy, then came to normal, then acted up again.
I think the best thing to do is just go back to an eta TB and leave the car stock. I dont want all these problems and it ran to my liking before. So, unless someone can help out, I am ripping this thing off.

jon

[Ryan Stewart]

mine never belched black smoke. You do ahve to port match the manifold.

[Jand3rson]

I had a 325i throttle body and an intake manifold on my eta, I never ran into any problems like that at all. I got a small jump in power (maybe 5-10hp), and noticed almost no loss in torque. If you are having all those problems, it sounds to me like while doing all that re-routing of stuff and making your own boot, you did something wrong.

[EtaSport]

Well I will probably have to try again. I put the eta TB back on tonight and the idle smoothed out and everything was back to normal. Another point in case, I broke the fuel purge valve that runs from the vapor canister to the TB and tried to substitute it with another vacuum valve. I got the correct part today. also yea, my intake tube was half-assed. I will keep this in mind for when i swap my head. Bad valve tap. Id love to get my eta cylinder head ported to match the intake, and do the same for the TB. Thats what you did on your car right Ryan? Thanks guys

jon

[gstuning]

I think your "i" TB is sticking, that happens to my throttle bodies, wd40 on the springs and other moving parts,

[RedBaron86325]

I am and have been running an b25 throttle body for a very long time. I never had any problem as you have described. I did; however, like the b27 intake manifold better than the b25. You can remove a butt load of material from the b27 intake ports on the head and the manifold. If you want to go relatively "all out" install b25 valves along with b25 valve springs (gets to be a tad expensive though). I'm running a b25 cam currently and can hardly wait to switch back to the b27 cam as I prefer a fatter powerband vs peaky powerband. My cam preference would probably change toward the b25 cam if I had another 1000 rpms (6200-6400ish).

I noticed that the return spring is only about half as strong as the etas, and when I force the the linkage back the idle will go down where desired.

The return springs seem nearly equal on mine. Could it be possible that it has been pulled apart and the spring(s) were not tensioned correctly? Those TB springs are kind of a bitch to re-tension once the spring has been released.

[EtaSport]

Well turns out my problem with fuel is from a bad ecu. It has been replaced once already for this problem at no cheap cost; 1700 dollars dealer installed. (a few other things included) So i am getting another ecu (not spending $1700) and hopefully this will take care of my fuel problems. I will also add that this happened a few times before i put the i throttle body on, so I know it wasnt just the TB.

I think I will stick with my eta intake, just open the TB port and possibly the intake ports as well to match the head. And as for my springs, I did some adjusting on the linkage and it seems to work better. The springs are totally different and the etas are shorter but thicker. to me they seem stronger. I put an extra return spring on just to make sure it didnt stick open on me. I also fixed my air intake tube. thanks

jon