newb question about swapping internals and tuning
newb question about swapping internals and tuning Im planning my next project. Want to either build a forged rod/piston 346 with a bump in CR, either a 228r or ms3 cam, larger injectors, upgraded pump, etc.
I know the car can not be driven with out being tuned, but Ive also heard not to start the car if injectors have been changed. So my questions is:
what process/order are guys using when doing a build like this? I would like to be able to start it and atleast idle before having it towed ti the dyno shop so I can make sure everything is good with the cam and heads first. Could you swap everything but the inectors and run it for a little bit, then go back and do the injectors last?
Also, would it be bad for the engine to do a few dyno pulls (as/after its being tuned since it would literally have 0 miles)? Or are guys having it safely tuned, and then doing actual dyno runs after it has a few hundred miles?
I hope this makes sense, please excuse my half-retardedness
I know the car can not be driven with out being tuned, but Ive also heard not to start the car if injectors have been changed. So my questions is:
what process/order are guys using when doing a build like this? I would like to be able to start it and atleast idle before having it towed ti the dyno shop so I can make sure everything is good with the cam and heads first. Could you swap everything but the inectors and run it for a little bit, then go back and do the injectors last?
Also, would it be bad for the engine to do a few dyno pulls (as/after its being tuned since it would literally have 0 miles)? Or are guys having it safely tuned, and then doing actual dyno runs after it has a few hundred miles?
I hope this makes sense, please excuse my half-retardedness
TECH Addict
Joined: Sep 2009
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From: PA/MD
If you keep your stock injectors in the motor after the build it can be fired up to check for leaks and things like that, even driven some, but will run rough and rich at/ near idle since a bigger cam actually takes less air/ fuel to run at and just off idle, but more air and fuel at higher rpms. Get the car running and checked out with the original injectors, then once the car is at the tuners, or being pushed around to goto the tuner put the bigger injectors in.
Biggest thing, like you said, if not tuned for the bigger injectors, don't run the engine with the bigger injectors in it.
Also pick up an extra set or two of spark plugs because you will have a good chance of fouling out your plugs with an untuned cam.
FYI, I run the good old cheap plain Autolite 103's,
Biggest thing, like you said, if not tuned for the bigger injectors, don't run the engine with the bigger injectors in it.
Also pick up an extra set or two of spark plugs because you will have a good chance of fouling out your plugs with an untuned cam.
FYI, I run the good old cheap plain Autolite 103's,
I agree with mark,
You can start it to check for leaks with stock injectors but DO NOT with your big injectors in it, You will fuel soak the cylinders immediately. If you want the tune to be correct make sure to put fresh plugs in it once the base tune is installed as the old ones will almost certainly be badly blackened.
As for the motor break in, If the motor is built properly the only thing you are waiting to have "break in" is the rings to seat and the assembly lube to make its way to the oil filter. The rings should seat in the first 8 or 10 min, and the motor should filter out the debris in the first 30 min of running. Once you change the oil and filter you will be as broken in as you need to be able to run the car on the dyno. A good tuner will know what to do to make sure you are set before beating on the car.
You can start it to check for leaks with stock injectors but DO NOT with your big injectors in it, You will fuel soak the cylinders immediately. If you want the tune to be correct make sure to put fresh plugs in it once the base tune is installed as the old ones will almost certainly be badly blackened.
As for the motor break in, If the motor is built properly the only thing you are waiting to have "break in" is the rings to seat and the assembly lube to make its way to the oil filter. The rings should seat in the first 8 or 10 min, and the motor should filter out the debris in the first 30 min of running. Once you change the oil and filter you will be as broken in as you need to be able to run the car on the dyno. A good tuner will know what to do to make sure you are set before beating on the car.
