On your second point, I beg to differ. Put too large a TB on, and whack it
wide open, and there will be a bit of a hesitation. Too much air too quick
from an idle. The computer has trouble compensating THAT quickly.
I agree that in theory, it shouldn't happen, but real world results differ
some.
TonyC
-----Original Message-----
From: david.clement@verizon.net <david.clement@verizon.net>
To: dakota-truck-moderator@bent.twistedbits.net
<dakota-truck-moderator@bent.twistedbits.net>
Date: Wednesday, January 07, 2004 4:46 PM
Subject: Re: DML: Throttle body..
>
>In article <016801c3d3a7$8c4a8900$d75f2241@a.tampabay.rr.com>,
>acellan1@tampabay.rr.com ("Tony Cellana") writes:
>>
>>
>> Some miscellaneous ramblings on the topic:
>>
>> Not knocking anyone's product or thoughts, just tossing mine into the
mix.
>>
>> TBs are a controlled hole in the intake manifold that will allow a
certain
>> amount of air into the motor. Some motors need more air than others.
The
>> amount depends on CID, RPM, and the tuning characteristics of the intake
>> manifold, cam and valvetrain.
>
>It is fairly easy to determine if you need a bigger TB. If you have (more
than
>approximately 1/2" H2O) vacuum in the intake manifold at WOT then you have
a
>restriction and a bigger TB is warranted.
>
>> Some motors want more air than others. TOO much air isn't always a good
>> thing though. It can cause bogging, off idle hesitation and/or stumble.
>> This is often seen when abruptly opening the throttle from idle or near
idle
>> (think jumping off alight or drag racing).
>
>The bog, hesitation and/or stumble is a carb characteristic. This does not
>happen with a port injected engine with a dry TB. When a carb is too big
you
>loose too much air velocity as you open the throttle if it's too big
resulting
>in a loss of vacuum that is needed to pull fuel from the bowls. This is a
non
>issue with port injection. If you were so inclined you could take the TB
off
>the engine and use your hand to control rpm.
>
>Dave Clement
>99 SLT+ CC 4x4
>
This archive was generated by hypermail 2b29 : Sun Feb 01 2004 - 16:29:49 EST