All,
After a tremendous amount of work both on regular chassis dynos and DynoJets I figured that I would give my two cents worth. In stock form, the V-8 TB's flow approx. 570 CFM @ 24 inches. With stock plates and work, the TB can be pushed up to approx. 670 CFM @ 24 inches. Larger plates can be installed, but the size for a streetable TB is limited by the web thickness between the two bores (actually a support for the throttle shaft) and the throttle shaft bearings themselves. We have used larger plates (out to 2.025 inches) without compromising the center web and without actually hitting the bearings. Flow @ 24 inches nets you approx. 710 CFM with the larger plates. All work has been done with either the stock shaft or one of our SS half shafts. Whether you use larger plates or the stock plates depends on your needs and your goals. The stock intake actually becomes the limiting factor at around 650 CFM. If you are contemplating a different intake (MPI) and using a healthier cam, !
!
then you will reach a point where you need to go to more CFM through the TB whether you choose to use a 4 BBL or increase the plate size in the stock TB is up to you. One thing you need to remember is that our engines use a MAP sensor, the setup is actually a speed density setup whereby the amount of air reaching the engine is calculated based on MAP signal at the base of the plates. The problem with larger plates is that the velocity through the TB actually decreases, the computer recognizes this and supplies less fuel. The results are a reduction in peak HP through the mid/upper RPM ranges. You can see this with scan tools and also see it on the dyno. This doesn't necessarily mean that big plates are bad, you just need to take the appropriate steps within the computer to adjust accordingly. If you don't plan on going the custom route with software, then smaller plates are better (you need to keep the velocity up through the TB). If done correctly, the factory plate size wil!
!
l net you more HP and Torque throughout the powerband with all after-market bolt-on equipment then larger plates will. This includes cam changes. We have been down both roads and it really doesn't matter to me if I use larger or factory size plates. The goal is to match the work to the intended modifications.............
Frank
---------------------- Forwarded by Frank T Holloway/CA/KAIPERM on 12/11/99 01:31 PM ---------------------------
Jpm699@email.msn.com on 12/11/99 08:38:00 AM
To: dakota-truck@buffnet.net@Internet
cc: (bcc: Frank T Holloway/CA/KAIPERM)
Subject: DML: Re: Re:Best throttle bodies?
Plus the F&B was only $90 bucks, I'd like to see someone else match that!!!
Jason
>Ditto here on the F&B TB. I don't understand how anyone can claim that
>one particular modified TB is better than another *unless* that person
>has tested all of them under the same conditions. It looks like personal
>preference and fortunately everyone seems very pleased with whichever
>modified TB they have purchased.
>
>This is great news for all of us to know that whichever TB we get, we
>will probably be very pleased with the workmanship and performance. How
>often can one say that about different manufacturers?
>
>Richard in San Antonio
>
>
>On Sat, 11 Dec 1999 00:32:46 EST Quiktruk99@aol.com writes:
>>I can't speak against a product I haven't tried, but from what I've
>>read, the
>>Quick D sounds like an incomplete unit. My F&B Stage 1 for $300
>>included:
>>fully bored & polished with airhorns milled flat, new s/s shaft, new
>>
>>butterflies, new button-head hold-down bolts, new cable brackets
>>(already
>>attached), new TPS & IAS sensors (already attached), new gasket, and
>>6-page
>>illustrated instructions. Also fired right up & idled at 600
>>immediately,
>>needed NO adjustment at all. This was for a "new core" no-exchange
>>t/b. Made
>>the truck a SCREAMER!! Also idles so smooth, I have to look at the
>>tach to
>>make sure it's still running! Now, maybe Quick D's makes you go
>>faster, I
>>don't know, but for the extras & the price, I'm happy I went with F&B.
>>Just
>>my .02
>>
>>
>>Kevin / NJ
>>99 Black Sport+ CC(no decals) / 318 auto 2wd / 3:92 SG
>>OEM wheel flares / 1.5"& 2" drop / Dunlop GT Qualifiers
>>F&B Stage1 / MSD 6a(plugs@.050") / Mallory 8mm Prowires / Echlin cap &
>>rotor
>>K & N Gen II FIPK / 180 HD t-stat / Flex-a-lite dual 12" fans( spring
>>of '00)
>>JC Whitney split-rear exit cat-back / Hooker tips / Lakewood traction
>>bars
>>Pace Edwards Roll-Top / Bedrug / Pop Lock
>>African rosewood interior kit / Wet Okole seat covers
>>Kenwood 140w stereo w/6 cd changer / silver DML stickers
>>visit my truck at: <A
>>HREF="http://members.aol.com/quiktruk99/DARKDODGE.html">
>>THE DARK DODGE</A>
>
>
>
>___________________________________________________________________
>Why pay more to get Web access?
>Try Juno for FREE -- then it's just $9.95/month if you act NOW!
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>
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