Flipping Air Cleaner Lid on TBI
 

I have an 87 silverado with a 305 TBI. It has a k&n filter already. Some people told me to flip the lid over to get more performance and fuel economy. Does it actually work on a TBI engine? I thought this trick was more suited towards carbureted engines. What do you think?

Re: Flipping Air Cleaner Lid on TBI
 

try it and find out. It WILL help get more air in, but it'll be hot air. So this is a question of quantity over quality. I've seen it go both ways, bepends on how choked up the engine is for air.
I know for a fact that my burb liked quantity over quality, esp with a sea level tune, and going through denver... it was blowin black smoke like a cummins... lots les smoke, better MPG and performance once it was flipped.
I've done it on TBI cars with both results... so it is up to your truck to answer your Q.

Re: Flipping Air Cleaner Lid on TBI
 

I do it on my truck During the summer months. and in the winter I flip it back over and it tends to heat up faster.

Re: Flipping Air Cleaner Lid on TBI
 

i drove it today with the flipped lid. Definetly an improvement. Right off the bat seems to have better torque. When you punch it, it definetly pulls harder than before and with that awesome intake sound. Gas mileage, well, I'll have to wait until another fill up for that since I have been driving this tank with a heavy foot. I'm guessing I will have to clean the filter more often since it's open now though.

Re: Flipping Air Cleaner Lid on TBI
 

I flipped the lid on my '87 305 and got about 1.5mpg increase and a little more throttle response, but it is bone stock.

Re: Flipping Air Cleaner Lid on TBI
 

My 96 Vortec 4.3L likes having the air cleaner lid pulled right off. It has a cylinder style air filter from the factory, but draws all it's air through a tiny hole in the passenger side fender.

Slight hint of the intake noise when you take the cover off, not nearly like an old 350 has when you flip the lid. I'm thinking about getting a cold air intake for the truck just to get a bit more engine noise. I personally think the exhaust note on the V6 sounds terrible, but the intake noise almost sounds like a V8

Re: Flipping Air Cleaner Lid on TBI
 

Certainly an improvement guys. I last took an honost MPG calculation in the winter time, probably march. I remember that calculation, I drove the truck easy, but it was winter time, so occasionally I would let it idle a bit to warm up. I averaged only 11 mpg. Did the air cleaner flip, and drove it this past week or so. I drove it hard, harder than I usually drive with full throttle bursts, and a few tire screeching take offs. I was trying to see what improvement the flip made and it sure as hell made performance improvements. What's even more suprising, I got an honost 14 mpg driving it hard! This time, I am going to drive it "normal" and see what I get. I'm predicting about 15-16 which is awesome compared to my old 1978 f150 9 mpg guzzler! Flip those lids!

Re: Flipping Air Cleaner Lid on TBI
 

winter fuel also gets worse MPG on top of the warm up time.