y pipe?

About three weeks ago my y pipe blew off when I took off into traffic no big I put it back on a week later it happen again a week later it blew off 6 times in a 5 mile drive now I'm running 14 lbs of boost but it pops off much lower like 5 lbs so I order one of the after market chrome y pipe and installed now it makes it to 8 lbs bfore it goes I also installed new t clamps and other than that i did the free boost mod and fipk air filter 6 monthes agoother than that its stock oh and I drive a 91 vr4 any ideas

If the y pipe you bought doesnt have rolled edges then it cant hold the coupler.

My new y pipe does have roles edges

Could it maybe be the cats clogged and causing back pressure in the system it is factory

Could it maybe be the cats clogged and causing back pressure in the system it is factory
No, if cats were clogged the car would just run like shit and have no power.

It sounds like you aren't getting the clamps tight enough. I've never heard of anyone blowing aftermarket y pipes off and there are people making HUGE power on them.

Does the coupler fit properly?
Is the coupler free of oil and grease?
Your T bolts may not be tight enough.

Spray the pipes and inside of the couplers with hairspray. Tighten the t-bolts down harder, if that doesn't work...ghetto but effective, you can jam a tennis ball in there to block it from popping off.

EDIT: let me rephrase that before somebody gets a tennis ball sucked into their TB. You can jam a tennis ball in between bend of y-pipe and battery iirc. I personally have never done it, but have heard from a few people who have done it.

i replaced the clamps and cranked them down with a rachet now it will hold together for about a week (300 miles) but the vacum linethat attaches to the y-pipe will jump off every couple of days and it seems as if the coupler is strecthing out could my timing be off (making the car run lean) and causing the problem equally it idle high (1300 rpm) but thats nothing new it done that since i bought it thanks for the help guys

How much boost are you running. Bottom line, you should pressure test. You should be able to hold 20-30psi no problem. Any piping that isn't holding that much needs a t-bolt clamp, any vacuum hoses that aren't holding are probably old and dry rotting and need to be replaced. At stock boost pressure there is no reason anything should be popping off or loose...end of story. Regular idle should be 700rpms. Seriously, pressure test and replaced old hoses and tighten down piping. With a new rubber gasket and t-bolts on a metal y-pipe with rolled lips, I've never heard of one popping off at anywhere near stock boost levels.

i replaced the clamps and cranked them down with a rachet now it will hold together for about a week (300 miles) but the vacum linethat attaches to the y-pipe will jump off every couple of days and it seems as if the coupler is strecthing out could my timing be off (making the car run lean) and causing the problem equally it idle high (1300 rpm) but thats nothing new it done that since i bought it thanks for the help guys

When I bought a cheap aftermarket Y-pipe, it came with a cheap coupler that degraded and would balloon under pressure. Sounds like what you're describing, so I'd say get a good coupler.

As for the line that connects to it, you can try replacing the vacuum line with new hose and/or using a small fuel line clamp on it.