new motor exhaust leak and missing under load

i just put a new motor in my car (again) and the exhaust keeps leaking i can tighten everything up itll be fine for a couple days than start leaking again and get worse over time so i thightin and it happens again. when i go to leave from a stop i have to tap the gas to get the revs up let off the clutch a little than hit the gas again or it boggs out on me and when i start to accelerate to pass someone it chugs at lower rpms. if i floor it it seems slower than at 3/4 throttle. i love em but hate em, wanna burn it
 
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We need more info on the car. What engine did you put back in? NPI, Pi, what mods are done to it. If its a 97 npi/pi with the two coil pack set up still I'd run the codes and check for a missfire from a bad plug wire or cp.

Need more info.

The exhaust leak, use lok tite on the bolts (blue) that way they will stop backing off.
 
i didnt know they made locktight with a high enough temp. for exhaust but ill get some blue, i already have the red stuff that wont work though right.

its a mark bottom end with npi heads, pi cam/ intake manifold, bbk shorty to xpipe magnaflow catback, steeda cai. still has the two coil packs up front, i had the codes checked at the parts store and it said egr valve, o2 sensors
 
Which o2 sensors? The front ones can cause issues if they are bad, they control the fuel trims.

Egr can also cause the same type of issue. Get those fixed first and check back. The o2's are likely from the exhaust leak if the leak is before the front set.

I think red is ok but its a step tougher than the blue and it may be hard to get the bolts loose after. I've always used blue lok tite with out issue.

What were the exact codes they gave u?
 
ill check on the codes but im pretty sure its cuz i dont have cats for the o2s and i dont have the egr on my car. its probably cuz i didnt do the egr delete correctly? its deffinatly leaking at the header but it seems like its leaking where it meets up with the xpipe but even with everything all tight i can hear a little popping if im driving next to a wall or fence.
 
You need to put the egr back on if you didn't get a tune for it. The computer allows for something like 10% emissions back in and tunes for it. The car will run like crap w/o it. You also nee do get all your leaks fixed and tightened up. Those too can cause issues and driveability problems.