what year q45 throttle body for ffim
- Thread starter redsupra_Dragstar
- Start date
I think they're all the same, but go with the one that looks like an overinflated early 90's Maxima.
The Q45 is normally used on a FFIM. For it to work on a stock manifold an adapter plate would have to be made/welded to the TB mating flange. In addition, the TPS would have to be re-wired and linkage fabricated. This is not a plug & play mod.
To achieve the higher flow afforded by the Q45, the the rest of the piping and intercooler intake/output would need to be changed over to 3". Anything smaller would become a restriction and negate the Q45's higher flow.
To achieve the higher flow afforded by the Q45, the the rest of the piping and intercooler intake/output would need to be changed over to 3". Anything smaller would become a restriction and negate the Q45's higher flow.
Better approach may be to ID any other restrictions/bottlenecks in the system before bothering with a TB.
So the point being made as i am understanding is that its pointless to use a Q45 TB unless your are using 3" piping throughout the intercooler setup??? Which does make sense I am jsut confirming my thoughts and understanding.
When you run piping for a forced induction system (i.e. a turbo), the smallest diameter of the piping, the TB, the intercooler in/output becomes the most restrictive. The compressed air becomes "more compressed" in a sense restricting flow...it's Bernoulli's Principle at work...you will get only so much flow through a given diameter. You can do this with psi and/or volume...psi will work to a point, then you have to increase volume. The Q45 will do that, but you have to have the rest of the restrictions removed in the system as well or it doesn't really matter.
Flow is what you are actually after...more O2 molecules to support combustion in the cylinders. You can add gas all day, but if you don't have the O2 it's not going to burn efficiently.
Flow is what you are actually after...more O2 molecules to support combustion in the cylinders. You can add gas all day, but if you don't have the O2 it's not going to burn efficiently.
The same theory as having a 3" exhuast pretty much right. The more flow the better. I just wanted to make sure I was understanding right which I was. Thank you for the Science class.:icon_bigg
Conversely you might actually hurt drivability by going that large as the Gas speed through the system drops and you need time to fill the volume added and end up with perceived lag.
Your Turbo moves xx cfm of air at a given boost pressure what you're after is a pipe diameter that's small enough to flow that amount without it increasing speeds to a critical point (mach .4/304 mph).
People often get caught up in the "Bigger is Better" thing with Turbo's then bitch and whine about "Lag" and blame the Turbo when it's just a badly thought out system that's to blame.
Your Turbo moves xx cfm of air at a given boost pressure what you're after is a pipe diameter that's small enough to flow that amount without it increasing speeds to a critical point (mach .4/304 mph).
People often get caught up in the "Bigger is Better" thing with Turbo's then bitch and whine about "Lag" and blame the Turbo when it's just a badly thought out system that's to blame.
Those problems should be solved by choosing the right parts to use and by tuning the car when it is done. Correct or Incorrect??? Or Just by not giving a massive overload of air and not enough gas and vice-versa
IJ. said:
Yep...very true. You need a turbo that will move the volume of air required in a short period of time. Like IJ said, you gotta think this through. A restriction in the system will increase speed for a given psi (Bernoulli's Principle again) and can cause the flow to hit the critical point.
And you have to have the fuel (injector size with supporting fuel pressure) to match.
Last edited:
Ok thank you very much guys. I was confused at first but it's all explained now and I understand. haha
It all gets a bit nerdy doing the math but really pays off in how the car drives when you get it right! 
Dave: LMAO I almost choked on my sandwich laughing!
Would be cool to catch up if ya make it down here!
(I really have to get off my butt and visit the States one day)
Would be cool to catch up if ya make it down here!
(I really have to get off my butt and visit the States one day)
I've worked with a few aussies. Australia sounds like an awesome place to live. I would love to vacation there. You should come see the states aswell. What part of Australia are you from?
91SupraTurbo said:
no
intake is not so simplistic.
Volume is only part of the equation. Gas velocities is the other and on the intake part it has as much importance as volume does
BTW
Q45 tb you are stuck with just that ONE sized TB.
For FFI there is only ONE way to go and that is with a 86-93 Mustang 5.0 Throttle body.
Availalbe from 65mm to 105mm. Anything else is just pointless as you have zero option than just the one TB. Sized to fit the system and HP goals Not to big or not to small.
Q45 tb you are stuck with just that ONE sized TB.
For FFI there is only ONE way to go and that is with a 86-93 Mustang 5.0 Throttle body.
Availalbe from 65mm to 105mm. Anything else is just pointless as you have zero option than just the one TB. Sized to fit the system and HP goals
Not to big or not to small.