80mm throttle body?

[MingisDew31186]

Hi, I was reading the tech and I see the 3.8 v6 has a huge throttle body 63mm! I was searching around and I found a 80mm throttle body. I am a little skeptical...Is that even worth it...or is just a crap [img]graemlins/bs.gif[/img] Well, if you have any suggestions get back to me thanks. [img]tongue.gif[/img]

[Jeff Pristelski]

well, keep in mind the area of a circle = pi * radius^2

lt1's have a dual 52mm (i believe) tb, so the total cross-sectional area of this tb is close to
1682*pi...

our cars, with a 63mm have a cross sectional area of about 992*pi,
so in theory the lt1 dual tb will flow nearly 70% better than ours...

now look at the 80mm, cross sectional area is 1600*pi, a huge difference compared to our weak little 992*pi... and really close to what a lt1 tb would flow...

Actually the lt1 would only flow 5% better than an 80mm, so you should get a HUGE improvement

now looking at all of this, let's hope that TB wasn't for a grand-national... :(

[Backfire]

You would really want to flow test those before making that jump. You probably don't need that large a piece. There were a couple of posts awhile ago concerning larger TB's. Going to an extreme like that is not always good for performance.

[Dominic]

Our cars flow 350-400cfm maximum, there is no exception unless you plan on going above 6500RPM (eek).

Our current throttlebodies are seriously oversized as-is, you would gain nothing from getting a larger one - sorry.

[wolf]

TB flowchart

throttlebodys only flow as much as the engine can intake
so if at wot you motor only sucks 400cfm, a tb that flows 650 cfm wont make a difference,the motor will still only pull 400 cfm

63 mm is a huge tb for a v6

[ June 12, 2002: Message edited by: wolf ]</p>

[Dominic]

<blockquote>quote:</font><hr>Originally posted by wolf:
TB flowchart

throttlebodys only flow as much as the engine can intake
so if at wot you motor only sucks 400cfm, a tb that flows 650 cfm wont make a difference,the motor will still only pull 400 cfm

63 mm is a huge tb for a v6

[ June 12, 2002: Message edited by: wolf ]<hr></blockquote>

Our TB is 68mm, and that is a VERY helpful link. I really appreciate you finding that, thats something I believe we've all been looking for!

[wolf]

Thanx Dominic
[img]graemlins/evilgrin.gif[/img]
*cough* *cough* Technical Archive *cough* ahem... :D

[12secondv6]

Stock is 65 mm
There is one modified tb out there.
Thrasher made/ makes a modified one for us.
It is 67 mm, yes modified to 2 mm bigger.
I spoke with the guys at www.grandprixstore.com a while back about this, not worth it.
$500 plus core charge.
whoop de frigin do.
Not worth it in my opinion.
80 mm, will it fit on our cars? If yes, got a link?

[ June 12, 2002: Message edited by: 12secondv6 ]</p>

[Arctc Wolf]

it isn't worth it unless you are gonna start adding displacement. if you got the .02 overbore pistons from 3800performance.com, you'd get 1.5 cubic inches more displacement. The only way I see needing a bigger tb is doing heads/cam, pistons, forced induction, and maybe stroking. Also, cfm makes a difference, but so does smooth airflow. the bigger tb will need to be match ported to the upper intake manifold so airflow is smooth and not choppy or rough. on a stock car, it will maybe add a little throttle response, but that's it. just work on other stuff and get this after you've gotten all of the basic bolt-on's installed.