I just bought 30 lbs injectors ,my car has the 24lbs right now , if i change them, will the car start and run properly without a tune?

 

No. You have to get a tune with injectors.

 

NO, you must tune!!

 

it will run, but it will run pig ******* rich. No tune, no injectors.

 

yea I have to agree with the other guys...you can get a basic tune for like $150 from a speed shop like speed inc and it will improve your cars performance all around

 

More fuel,more power. Seriously though,tune first.

 

If you want to blow up the engine so you have an excuse to rebuilt this is the perfect plan. All that extra fuel will wash down the cylinder walls compromising them and the rings then the fuel dilution of the oil will attack the bearings.

 

Kind of a hijack, but when does it become necessary to up the injectors? IIRC, mild cammmed cars with stock heads should be good with stock. Correct?

 

With cams it can't hurt to up the injectors especially if he plans on getting some good flowing heads to compliment the increased lift etc. Increased air + more fuel + hotter spark = more power !

 

Right, but when do you get to the point where you can flow enough air to need bigger-than-stock injectors?

 

All depends on the car. Generally when injector duty cycle is over 85%. That being said a full bolt on car, would be just fine with bigger than stock injectors if you plan on doing motor mods later on.

 

Thanks Buff!

 

Another Hijack - with LT1edit, there's a function to just change the injector size by typing in the pound rating... if your familiar with this (whoever might be) is that all that is needed to retune it for the bigger injectors? Obviously, dyno time and experienced tuner help is needed to fine tune the vehicle - I'm just talking about keeping it from hurting itself as you say it will without a tune.

 

well you need to know fuel pressure rating the injectors are rated at. IIRC the ford injectors are rated at a lower fuel pressure, so a 30lb Ford injector on our cars is really almost a 32lb injector. You really need to get a datalogger to watch the BLMs to make adjustments.

Matt