Hey guys. I've got a '95 F-150 XLT with a 5.0. I'm about to redo the exhaust and have a question. I've have some people tell me that I have to keep the same size pipe under there or I'll have issues with not enough back pressure on the motor, is this true?

 

It isn't true, but be aware it is likely going to be a pain in the *** getting the old exhaust off.

 

I'm sure it will be, but I don't have many options. The cats are clogged up so I'm just going to delete them and put straight pipe in their place and replace the muffler. Right now I'm just doing from in front of the first cat to the rear of the muffler and I'm going to replace the rest later once I have more funds to put into it.

 

...so to be clear, if I run 3 inch exhaust throughout it won't effect the performance or mpg negatively?

 

Yes it could. this is super common for young people to do.

Measure the exhaust you have, and go just a touch larger if you want persormance.

If you go super huge you can absolutely backpressure the engine. I cannot tell you how many times I see this happen.

 

If you install a 3" exhaust on a 5.0 you will lose torque, 2.5" pipe is plenty.

 

Ok thanks guys I wanted to make sure before I got myself into trouble

 

Also, prepare yourself for a CEL with no cat. OBDII vehicles are kinda finicky like that

 

2.5" is plenty.

We did exactly what you are doing on a 95. You won't have a CEL as long as you keep the O2 sensor installed. You'll need to put a bung in the new pipes.

We used a Ypipe from an early model 302 and put a flowmaster super 44 in it with 2.5" exhaust pipe. It sounds fantastic.

 

Many years ago I installed a Gibson 3" cat back system on my '87 Bronco. It killed the low end torque on the 302. I went back to a 2 1/4" system as soon as I could.

 

This would be an OBD1 truck, obd2 didn't start until '96 in 1/2 tons.

 

My bad, i though he said it was a 96

 

I have a 95 F150 and it has OBD 2 .

 

Mine is OBD 1. Yours was probably made towards the end of 95

 

Interesting....there are some supposedly OBD-2 1995 model year F150s with California emissions. Perhaps yours is one.

Post a photo of the sticker on the driver side door jamb and the VECI label under the hood.