Throttle Body Boring

Subaru_Nation555 · Post by **Subaru_Nation555** » Wed Oct 27, 2004 10:56 pm

I was browsing boxer4racing.com yesterday and they had a bored out throttle body for $185. I'm not actualy considering this, I was just wondering if anyone has tried this mod and if it works?

tris91ricer · Post by **tris91ricer** » Thu Oct 28, 2004 12:47 am

I have an extra TB if you'd like to experiment.. name your price, cause it'd be alot less than $185.. in fact, I have a whole 91 intake manifold.. complete and untouched.

vrg3 · Post by **vrg3** » Thu Oct 28, 2004 1:00 am

If you actually bore out the throttle body, you need a custom butterfly, right?

mikec · Post by **mikec** » Thu Oct 28, 2004 1:16 am

Rev-Lab (http://www.rev-lab.com/) does it. They have pictures of before and after if you pick any of the chassis and then look under Power. I can't tell if they switch the butterfly, or just port the entrance and have it taper down to stock size at the butterfly.

Post by **Legacy777** » Thu Oct 28, 2004 1:24 am

Yes, if you bore it out, yes you will need a new throttle plate.

Subaru_Nation555 · Post by **Subaru_Nation555** » Thu Oct 28, 2004 1:28 am

Thanks for the offer 91legacy_sleeper, maybe sometime in the future. I was just curious on the topic

tris91ricer · Post by **tris91ricer** » Thu Oct 28, 2004 7:47 pm

will do.. looks like i'll probably have it some quite some time to come...

georryan · Post by **georryan** » Thu Oct 28, 2004 10:05 pm

Wouldn't the issue be to bore it out if your intake could pull enough air to mak the throttle body the weak link?

Our throttle body isn't the weak link in our intake track is it? Even if we put on a cone filter, our limit comes from our MAF, right?

scottzg · Post by **scottzg** » Thu Oct 28, 2004 11:23 pm

I think the throttle body is the last thing that restricts. the maf, the intake manifold, the airbox, and the heads themselves would all become restrictive before the throttle body. Although im not certain on this one, i can say with some confidence that having a disproportionately large throttle body makes it difficult to modulate power. Maybe someone would confirm?

mikec · Post by **mikec** » Thu Oct 28, 2004 11:29 pm

FWIW, this is directly from Rev-Lab's site:

This is only suggested when turbulence in the throttle body becomes the next step in optimizing your intake flow. (usually done after the exhaust, heads, etc.)

Sounds like it is indeed the last thing that is done, when you're trying to squeeze that last little bit out of the engine.

-K- · Post by **-K-** » Fri Oct 29, 2004 6:26 am

I have seen a lot more power than most of us here make go through a lot smaller TB.
I would not touch the inside of my engine, heads, intake mainifold (exept the injectors), or TB unless I wanted more than 300HP

EJ22_SLO · Post by **EJ22_SLO** » Tue Nov 02, 2004 11:50 pm

is there any difference (inner radius) between Ej22, Ej20t and EJ25 intake manifolds?

THAWA · Post by **THAWA** » Wed Nov 03, 2004 4:07 am

EJ22_SLO · Post by **EJ22_SLO** » Wed Nov 03, 2004 8:49 pm

are they compatible?
i'm thinking of: coffe mug mode, changing intake manifold & thottle body (if necessary) and switching pulleey (just lighter, not underdrive); after i change al that, reset ECU, leave it to learn everithing from scratch...

Could this work on my EJ22 engine? (unfortunately there are no EJ22T in Europe...

)

ehm..
Is it wise to mode engine with 250.000km (155275 miles) on it? Engone (so far) works like swiss clock... no problems at all... average milage is about 111,5L/100km (20,4 miles per galon)... oil consumption about 1 litre/10.000km, top speed 130 MPH (not legal even in EU

)

QuickDrive · Post by **QuickDrive** » Wed Nov 03, 2004 10:46 pm

I'm not sure that the coffee mug mod will work on the Ej22 non turbo.

As with modding an engine with 150k miles on it, bolt-on's shouldn't cause any problems with reliability if it's running like clockwork.

Keep bringing it up to 130mph and I can sense that clock losing the second hand though

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Throttle Body Boring

Throttle Body Boring