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Downsides to TB mod?

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Old 09-14-03, 02:28 PM
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Downsides to TB mod?

Just wondering if there are any downsides to the throttle body modification? I hate that goddamn cold idle anyway. I heard that you have to hold the gas down for the car to idle, otherwise it dies. Is this true??

Anyways let me know please, and thanks cuz I gotta pull my UIM soon, and i might as well get this done.

Thanks!
-Ross
Old 09-14-03, 02:46 PM
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For like 10-15 seconds, yes. I dont know if Id waste the time to do the mod again. I think the time would be better spent porting and smoothing the front lip of the tb.
Old 09-14-03, 03:58 PM
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I've done the mod a couple times and my car has always idled when cold. Modding the TB may give you a small amount of power but it mainly cleans up everything around it. You have more room to work with and you eliminate that coolant line that goes into the TB.
Old 09-14-03, 07:04 PM
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Originally posted by dr0x
For like 10-15 seconds, yes. I dont know if Id waste the time to do the mod again. I think the time would be better spent porting and smoothing the front lip of the tb.
Something like this?

Old 09-14-03, 07:30 PM
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From my experience on the Throttle body Mod...

Draw backs:

Drop throttle hesitation (pretty minor, but at low speeds when you lift the throttle, it may surge just a touch, if you come back on the throttle suddenly) Low speed (under 25 MPH) this may be more of an issue.

Cold idle is poor and may require help in cooler climates. (you can always leave the cold idle advance in place if this is an issue for you)

Advantages:
Quicker throttle response when warm (though you really need a turbo to feel the true advantage of the mod- On N/As the difference is very minor.

Cleans up throttle body.
Old 09-14-03, 07:33 PM
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JB weld failing to hold because you didn't rough up the surface enough and falling into the engine. KABOOM!!!!

Old 09-14-03, 08:30 PM
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Alternatively, just remove the Secondary Plates and not have to worry about holding the Throttle during start up. Same thing really.
Old 09-14-03, 09:14 PM
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I will be doing the tb mod very soon
There is one thing that i would also like to know

In removal of the cold start assist: would this affect idle of the car when cold? or just remove that very anoying 3000k start up?

Well that's probably as much i'll do to the tb

Not to sure about the termal wax thingy. Can anyone explain the draw-back of removing this function from the tb?

Chuch
Old 09-14-03, 10:58 PM
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I have to hold the gas for 20 secs or so then it'll idle cold just fine. however once I'm moving. and I want to stop. if I push the clutch in at 2-3000rpm it'll just stall out. so like a block before the stop. I have to push the clutch in while holding the gas down. slowing releasing the gas to manualy bring it down to idle. then I can start braking. hopefully still having enough time hence starting a blook back. I normaly only have to do this for the first stop. as it's warm enough by the 2nd to not stall.

kinda a pain in the ***. I've had it stall out a few times.
Old 09-14-03, 11:58 PM
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Dude, you could just heel and toe so you can brake at the same time

James
Old 09-15-03, 12:04 AM
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Or left foot brake after taking it out of gear
Old 09-15-03, 12:35 AM
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I left the thermowax in place and removed the #2 secondary throttles and linkages. No idle problems at all. If you slam the throttles open too fast it'll stumble but you learn how to avoid that.
Old 09-15-03, 12:53 AM
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Kim
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I did it to my N/A a month ago, and I felt a difference in acceleration, it could be the fact that the injectors were cleaned while I was at it.

I was told that when eliminating the BAC, it could cure the bouncy idle, and it did.
I also have to hold the throttle for like 20 seconds. If im lazy and takes off right away ill hold the gas with my pinkey-toe as I usuaslly drive around without my shoes on.
Old 09-15-03, 02:02 AM
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Originally posted by Kim
I was told that when eliminating the BAC, it could cure the bouncy idle, and it did.
The BAC valve is there to ensure a smooth idle irrespective of engine load. Fixing the problem would have been a better idea than just ripping it off. It was probably just dirty.
Old 09-15-03, 09:38 AM
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I dont have powersteering or A/C, so I guess that it is not used anyways
Old 09-15-03, 11:01 AM
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If you still have AC when you do your TB mod you can put your AC on full tilt. That way the idle should go up to about 900rpm and that will help you hold your idle while cold.

James
Old 09-15-03, 11:06 AM
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Use the throttle stop set screw to bump the idle a bit (up around 1,000RPM).&nbsp This is guard against the engine dying from aux. engine loads or intake leaks when the engine is cold.

Under 3kRPM, the engine does HESITATE when you romp on it - on the other side, this does help you drive smoother.

It really cleans up the aux. coolant routing, and it eliminates the stupid 90-degree coolant hose under the upper intake manifold.&nbsp If you remove your upper intake manifold a lot, this will keep the frustration factor down a LOT.

I do NOT recommend doing this for NA's, as I don't think the gains are worth it on those engines.


-Ted
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