Stumpalump

I live at 6000 feet and drive up to 13000'. I heard a hissing above the gas tank at 13000' and could smell a little gas. I opened the gas cap and air gushed out for 30 seconds. A lot of air. A whole lot of air. Is somthing wrong with a vent somwhere? I just past emissions testing and they checked the cap for somthing. Any sugestions for high altitude? With so many CAI on the market do some flow better past the traction controll box better than others? It looks like it's a tight fit. Thin air sucks. At 6000' Im down 20% power.

Formula350

iTrader: (3)

That's just outside pressure collapsing the gas tank a little, which causes pressure. Even shaking of the gas does that. Mine does it took sometimes when I take off the cap, but it's just a quick "whoosh" and the tank goes "bwomp" with the metal moving back.

Only thing you can do is get a turbo or a blower That's what they were designed for after all. High altitude bombers/fighters during WWII that just couldn't get the altitude they wanted due to air limitations. For you, a supercharger would be easiest I think.

Stumpalump

It funny that I vented the tank by taking off the gas cap at 13000 feet and air came out but when I got back down to 6000 it was even pressure in the tank. I'd like a supercharger but I just built a rockcrawler and then souped up my diesel tow rig. I'm not sure how much longer the wife will hold out with all these mods. It was "her" dad that gave us the smokin deal on this cool car last week so that should make it ok,right? Another thing is the old man across the street has a 97 SS Camaro with 40K on it. He claims it will blow mine away. He has a LT1 350 and the factory SS ram air hood. All stock. I just need to get this car a little faster than his before the big race. I'm hoping CAI,airfoil,relocated air temp sensor and cat back will do it. I may take the throttle body off and clean up the inlet and outlet with a drum sander unless you guys advise against messing with it. Why don't I read anything about mild porting them and MAF sensors. Can't I hack and sand that aluminum bridge out of the MAF if I'm carfull with the wires inside? I'm in thin air so the more I can get in the better. Yep I'm a freakin newby to fast cars but I've built jeeps, trucks and boats so this project ought to fit right in. This site is great!

speed_demon24

iTrader: (6)

If you want to mess with the MAF you could de-screen it, other than that keep it stock. Relocating the IAT doesn't do anyting and is a waste of time, an Airfoil might give you 1-2hp if you are lucky. Just get a CAI and good catback. As far as the hissing sound check out your evap and make sure it is working right and hooked up the correct way.

aboatguy

Actually its the exact opposite, there is less atmospheric pressure at altitude and the denser 6000ft air was trapped in the tank hence the whoosh at 13k.

The maf/tb are not really restrictions on stock LT1s, the best easy performance gain when I lived in COS was Headers, gears provided a better boost but there a little harder on the install scale.

Mike

Stumpalump

Mine has an air pump and the emissions testing folks went over the car with a fine tooth comb. Can you keep the air injection with headers? I just did gears on a Dana 44 and a Ford 8.8. I say bull to those that say you can't set them up yourself. It's not hard if you pull the chunk and do it on a bench. It pulls 2500 RPM in overdrive on the interstate and I wouuld think thats allready a lot. Our interstates are 75mph so Im probably going 80.

aboatguy

What state are you in? Kali does not allow LTs and I'm sure some other states are the same.

I retained all of my emissions equipment on my LT install and used high flow converters.

Formula350

iTrader: (3)

Inside, outside, close enough

Pntbll309

iTrader: (33)

Im from Colorado Springs I get the hissing from just driving around town when I go to fill up.