Throttle Body size?

I just recently ordered a cold air intake system for my '01 GT and figured while installing that, it would be a good time to put in a new throttle body. What kind is best, I was looking at BBK, and what size is best, the 70mm? Thanks for the help.

i was thinking about putting on 70 mm on my car, i can't imagine why not - for some reason everyone seems to keep it at 70 or 65. greater then 75 won't really do anything with out crazy mods. be sure that you do more then just a larger throttle or else the benefits will be minimal. and too big of anything on the intake or exaust could result in "diarrhea of the engine" - that is to say too much flow that leads to a loss of low end torque.

oh yea - don't forget to get the appropriate spacer to go along with the throttle body.

70 is fine. Also, look into getting another mass air meter. Its supposed to help out alot!

:bigthumb:

Under the same driving circumstances, would the larger throttle body and mass air sensor hurt gas mileage at all?

I havn't made the change myself, but it would make sence to me if gas mileage increased slightly. On one hand the more air makes for a better fire, but on the other hand what the fuck do i know?

but keep in mind that just replacing the throttle body and spacer won't suddenly open your car up, you've got to balance it with a change in the exaust manifold or a post-throttle body intake flow enhancer.


big words are fun.

TB,CAI, MAF all will help but also big gains can be had by potring and polishing that pretty metal box that sits on top of your plastic intake manifold.

I don't think a bigger MAF hurts anything if its the right size. Shitty injectors (clogged, otherwise), overreving, racing the fuck out of it, gears, and prolly cams and other shit would hurt your gas mileage.

Just spray the damn thing.

yo los - you keep saying "just spray it" what does that refer to?

Originally posted by BigDanTheMan
yo los - you keep saying "just spray it" what does that refer to?

He's talking about the "juice", more commonly known as Nitrous Oxide.

Originally posted by GTStang
TB,CAI, MAF all will help but also big gains can be had by potring and polishing that pretty metal box that sits on top of your plastic intake manifold.

You know I just read about that too. I'm going to have to look it up again and see what kinda gains were achieved.

He's talking about the "juice", more commonly known as Nitrous Oxide.

How bad does nitrous hurt engines? Ive been thinking about getting a 50-75 shot bottle, but i dont want to destroy my engine. Id only use it at the track, maybe.

i know that the block can hang with NO2 if the bursts are short, be sure to run extra high octane, 92+ to be certain that all of the no2 is burnt up. In california the highest grade you can get at the pump is 91 and my friend's old 67 gt didn't burn it all up and some excess no2 got into the upper manifold and blew that shit off.

Highflow knows all about this shit - wait for him.

My best friend runs a 150 shot. He recently took the motor apart for port/polish, just overall head rework. He didnt' have a problem, only one backfire which crumpled his K&N filter as it smashed into the front of the car in the engine compartment. As soon as that's done, he thinks he can push a 175 shot.

I think he's going to melt his heads, get pissed off, and start bitching about how his life sucks.

:cwm27:

I don't see a problem with running a 50-75 shot occasionally, depending on the motors current condition and all. If the motor had high miles and small problems, I would think twice about it.

I think ZEX makes the easiest and safest kit to use. It's just nitrous and not fuel/nitrous mix.

Take a look at this, here's what happens when you get a nitrous backfire. Ouch!

I was actually planning on getting the zex kit, and the highest gas ive seen around here is 93, and its hard to find. Its usually 92 though. My intake & exhaust runners have been ported and polished.

A stock 302 block can handle up to 150hp shot if you get the right kit. Avoid any wet system that is not a plate design. Also run highest octane avialable, step colder non-platinium plugs, bump timing down 2 degress per 100hp added.


Hi-flow: porting that intake box gives around a 15hp gain. If anyone is interested let me know I do them for $40.

40 bucks for porting? first i'd feel obligated to purchase a manifold worth porting. gt stang - do you do upper and lower? how long does it take? where do you work at? what's the update on your pony

a stock motor 302 can handle a 175 shot easy, if you know what your doing. Had a Renegade car and got a junkyard 100k+ mile longblock, ported the stock E7's, put a Performer RPM intake on it, 24lb injectors, etc. backed with a C4 & 3.73's. Car went 11.2 with a 200 shot. Stepped it up to a 250 and the car went 10.86. Stepped it up to a 300 but the fuel solenoid didnt open, and went real lean. Blew the intake plate into a million pieces, cracked the intake in 3, etc.

put a new intake on it the next day, and the motor ran fine. Had to run on motor though cause the piece of the intake plate slided through the line, and we didnt realize it til after the run. Got a picture of the car in MM&FF for that though :bigthumb:



GTStang...whats wrong with a wet nozzle? Ive sprayed everywhere from 50shot to 200 shot on a wet nozzle, and never had any problems. :confused:

Originally posted by YJGWRacing
GTStang...whats wrong with a wet nozzle? Ive sprayed everywhere from 50shot to 200 shot on a wet nozzle, and never had any problems. :confused:

Nothing, but the key phrase is, "if you know what your doing." For the beginner it would be wise to run a dry system, opposed to a wet system.

I still would be weary about running anything more then a 100-150 shot on a high mileage stock motor. It may hold up to a few shots, but who knows down the road after more usage.

There is nothing wrong with running wet on a carbed intake because it is designed to flow both air and fuel. I would never do it on a FI car cause the intakes are designed to flow just air. In FI intakes puddlin tends to happen which is very bad. Many people run them on FI cars and have no problems. But I would not risk it!

I work at the 5.0 Pro-Shop. My enine just finised up its dyno tuning and the car is at my friends body shop. Im painting it this week-end hopefully

And where is it located?

Ah yes, the Nitrous Oxide debate.

The block will take a 200hp shot without a problem. Actually, all the components will, IF you have it tuned perfect.

Problem with a wet nitrous system on an EFI car is the picture above, which appeared to have the most dangerous type of wet nitrous fogger possible. At the T/B. Nitrous oxide is NOT flammable. Only when it's mixed with a fuel like gasoline does it burn.

When the fuel and air/nitrous charge is combined all the way up in the intake of an EFI car, it creates a serious explosion hazard because the fuel is confined within the plenum. A backfire can ignite the highly explosive mixture with no area to expand and it basically becomes a bomb.

Most people use the logic, 150shot or less on the forged piston cars, and 125 or less on the hyper piston cars.

Keep in mind, if you're tuned right, you'll never make 150hp on a 150shot. The car should definately be de-tuned for Nitrous applications, both with timing, and colder plugs due to the greater risk of detonation/pre-ignition.

A dry nitrous kit relies on the fuel injectors to supply all the fuel so there will be less fuel in the intake system, and therefore less chance of it blowing up.

A wet nitrous kit supplies additional fuel through a fogger plate, and the fuel enters the intake system further up, creating a larger risk to explosions.

Bonus for dry system, safer. Bonus for wet system, less strain on injectors.