70mm tb? bigger,smaller, or what?
- Thread starter rd02gt
- Start date
hognutz
New Member
do not put a tb on without a plenum. waste of money. if you buy a plenum then use the TB size they recomend for that plenum.
Accufab tests show 70mm TB works the best with the accufab's having the most overall gains. Accufab and users show this. If you just want to get the TB and then get the plenum later I don't see a problem with it, however you won't see any gains from what I've heard.
hockeymonkey83
New Member
a new plenum pretty much does what a intake spacer does for a carb it increases the inkae volume a little but it also had a better angle design then the stock, this lets the air follow air less restrictive path then stock, kind of like the change from a manifold to headers, I would say go with the accufab plenum and the Ford racing 70MM throttle body accufab recomends a 70MM throttle body and the Ford Racing one is a good price plus it comes with a new TPS which is good for a little increase in MPG
Shawn
Shawn
hockeymonkey83
New Member
bigger is neccissarly better, the FRPP is just my personal choice I thin it gives the best bang for the buck
twogts4us
15 Year Member
I would have gladly paid the additional $10 bucks for the 75mm over the 70mm TB, but it wasn't recommended...so I stuck with the 70mm - and couldn't be happier. Bigger is not always better. I highly recommend the Accufab plenum and Accufab 70mm TB (though you have to transfer the TPS over from your stock TB, this really wasn't a big deal...two, albeit very tight, screws but adjustment necessary, really pretty easy). Accufab makes high quality stuff.
Brisk281GT
New Member
Accufab 70mm TB and Accufab plenum is the best setup for a N/A Mustang. The 75mm TB has shown to get a bit less hp than a similar 70mm TB. If you have forced induction of some kind then go 75mm but no bigger than that.
Someone should be along to post a link to a website that shows pulls with both a 75mm TB and a 70mm TB on a N/A Mustang... I don't remember the site.
Someone should be along to post a link to a website that shows pulls with both a 75mm TB and a 70mm TB on a N/A Mustang... I don't remember the site.
twogts4us
15 Year Member
Dark Knight GT
I can't get it up......ok that didn't sound right.
All this talk about throttle bodies is really getting rediculous. No disrespect to those of you who use a larger throttle body than stock either. However, the top racers on this board have used larger throttle bodies than the stock one and have gotten 0 positive results with them. No decrease in 1/4 mile times nor any increase in power on the dyno. I can even testify to some of this as I have had both a 70mm and the stock 65mm throttle body on my car. In all seriousness, the 65mm seems to make more power than the 70mm. Now, I know many of you are under the impression that if you couple a 70mm throttle body w/ a good plenum, you'll make more power with it. In some cases, this seems to be true while in others, it isnt. The key to making hp from induction modifications isnt through a huge throttle body. Remember, just because you're letting in more cfm's of airflow doesnt mean you're going to make more power with it. There is the issue of velocity that must be considered. When you go to a larger throttle body, you increase the cfm's of airflow, however, with a larger opening, you allow the air to flow through in a less condensed form which means there will be less o2 in the incomming airflow. Less o2 means less power. In my personal opinion, I would go no larger than a 70mm throttle body, even with an aftermarket plenum. Especially not an 80mm throttle body. That is over kill if you ask me.
white99gt
Founding Member
Unless you have other major mods already leave the tbody alone.By itself its a waste of money PERIOD.
Use the money for the tbody and get pullies or some gears.
Use the money for the tbody and get pullies or some gears.
Dark Knight GT
I can't get it up......ok that didn't sound right.
white99gt said:
Weren't you the guy who did the before/after dyno tune test between the 65 and 70mm throttle bodies and ended up loosing power up to past 5k rpms with the 70mm throttle body ?
white99gt
Founding Member
Dark Knight GT said:
LOL yep.
But i got tired of preaching it.
.They never listen ,because the mags are always right
You are talking about THIS dyno
blue -stock 65mm
red -70mm
View attachment 525701
Dark Knight GT
I can't get it up......ok that didn't sound right.
Thanks for the dyno sheet. I appreciate it. I'm getting my car dyno tuned here soon, once I get all my parts in that is. Anyhow, I have a spare 70mm throttle body. I might talk to the guy doing the tune. I know him personally and he's becomming an SCT dealer. Maybe he and I can work something out and we'll do a before/after test as well with the 70mm throttle body and see what my result is with all my mods. Maybe then it will sink in even further with two guys who have dyno proof that the 70mm throttle body is pointless on a n/a GT.
