What size throttle body should I get for a 2003 GT (70mm or 75mm) ? Im going to get the accufab TB and plenum. My mods are in my signature. I dont plan on geting a supercharger.
Now, a few people who have never tested or probably even seen the parts will chime in and quote the one MD test that showed a slight difference between the two that is within the realm of data scatter, but the fact is both will make the same power at stock levels, and once mods get added the 75 starts pulling ahead.
I'm with the majority. 75mm all the way. The Modular engines don't suffer from low speed drivabilty problew with a throttle body that's too large for the application the way the old 5.0L OHV's do.
And based upon this was exactly why I bought a 70mm Accufab TB to go with their plenum on my 02...absolutely no regrets. Some HAVE reported loss of low end with the 75mm, and I'd believe it, since mine feels exactly as it did prior to this mod until 3K + RPMs. If you're planning to stay N/A as you stated, I'd really recommend the 70mm.