Throttle Body Upgrade

It's a slippery slope.
Is there more power to be had? Yeah, there always is.
The question is how much and what is the cost for that power.
If you buy a $200 TB and a $200 meter, $200 injectors, then pay someone to tune it for what has to be at least $500+, did you get your $1100 worth if you only gain 20rwhp?
You can't only reliably pump so much boost (or power) into a stock engine. The last thing you want is a blown head gasket.

If it runs good, i'd leave it until you want to do a heads/cam/intake swap.

At most take it to a dyno shop and see how much power it makes and where the air/fuel is. If there is something dangerous about the a/f, then take the proper action.

Cronk1388 said:

hey guys I have a 89gt with a Kenne Bell 2.2 a bbk cold air intake, 255 fuel pump, Full catless exhaust. I bought it this way. As far as I know the rest of the car is stock. Injectors,throttle body and mas air flow. Never been tuned from what the other owner told me. Car runs strong no issues just curious should I upgrade the throttle body and injectors? Will it make a big improvement? Any tips will be helpful I’m knew and this is my first foxbody. Thanks!!

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I agree and disagree with some of these comments. A lot of people don't know what our Kenne Bell superchargers like and dislike and why. Take it from me, I know a couple things about them because I have a stock 302 Kenne Bell 2.1L supercharged car.

What @2000xp8 said is very true, how much are you willing to spend to gain HP? What are your goals? Is this just a fun street car? Before doing any modifications you should hit the dyno to find out where you are with your HP/TQ. If you choose some upgrades then you can go back to the same dyno and see what power the new modifications brought you. Going to the dyno may also uncover any issues that you may have and be unaware of like if your lean in high load situations, unusually high Intake Air Temps (IAT's or also known as MAT). This is very important to know since KB's twin screw rotors produce a lot of heat while in boost.

Before I go any further, very nice car!!
My $.02 on your vehicle. You said PO (previous owner) didn't get it tuned. Most likely your car has a Kenne Bell computer with their base tune for a supercharged 302. Located behind the passenger kick panel you might find one of these.....

You having one of these computers or not is very important. Please verify before making any changes to your engine.

Next, What does a Kenne Bell supercharger like? Well, it likes a very UNRESTRICTIVE intake. KB's like big MAF meters, big intake pipes, big throttle bodies!! The opening on your inlet manifold should dictate the size of your intake components. The opening on my Flowzilla inlet is 90mm, therefore I have a 90mm Accufab throttle body along with a large Anderson power pipe leading to a huge K&N filter inside my passenger fender (cold air!). The more cool air and larger the intake tract is the more your Kenne Bell SC is going to like it and you'll net more PSI of boost too! More boost = more HP.

Please verify and report back with crank pulley size and supercharger pulley size. We need to verify how much boost you're already setup for. Do not assume you have a stock size pulley. A popular modification is to run a F-150 6.5" pulley which will spin your blower and accessories faster. Faster you spin your blower the more PSI you make.

This is my car BTW

I would think that he doesn't have a kb computer setup considering in the pic there looks to be an fmu.
I don't know much about the kb computer setup, but I can't see doing that and an fmu.

2000xp8 said:

I would think that he doesn't have a kb computer setup considering in the pic there looks to be an fmu.
I don't know much about the kb computer setup, but I can't see doing that and an fmu.

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I noticed that blue FMU on the strut tower after I posted. You may be right but I'd still like verification just in case somebody hacked or mismatched the combo. Although many have successfully run FMU's, with such a nice car as this, I'd like to see the new owner ditch it and set it up the best way.

I wonder at what amount of boost does an FMU become a liability?

Get a wideband O2 so you can monitor AF ratio. Then you'll know if the tune is where it should be. If not, tweak until it is.

I use the PLX brand in my 92. I also have the vacuum/boost module so the pillar mounted single gauge can be toggled back and forth between the different functions. I haven't tried the smartphone adapter as of yet.

https://www.plxdevices.com/PLX-Wideband-O2-Air-Fuel-Ratio-Sensor-Modules-Gauges-s/125.htm