Got some questions about modifications, a lot of questions.
 

Okay so I have a '92 fastback SE. N/A because I dont have enough money to go turbo. But I recently put on new 4-2-1 headers, and a 2.5" cat back exhaust. First of all, is 2.5" overkill on a NA motor and will I lose too much back pressure to the point where I lose power? And second of all, I could not get my EGR to go back into my headers so I just blocked it off, the port where it comes back into the header and the "thing" that comes from the bottom of my stock headers back into my intake. Blocked them all off, will that negatively effect my power and if so where at in the power band? Will it help at all in any of the power band? I talked to a 240 owner where I live and he had blocked off his EGR and said it helped for the most part so I did so myself. Good choice or not? And second of all, I ordered a Megan Racing test pipe for my exhaust, Im not too worried about emissions because here in N. VA, its not tested because the air is still pretty clean, but will that absolutely kill my backpressure enough combined with the exhaust to lose power? I have no cat on right now, just a gap between the headers and cat back, and other than being outrageously too loud, I dont feel like I have all the power I should on the few drives I have taken around the neighborhood to test it out while waiting for the test pipe on back order. Should I cancel the order and just get a high flow cat or what? Which will benefit me the most?
And by the way, blocking the EGR didnt throw a CIL or anything of the sort, but I know its probably going to effect my gas mileage horribly, is my assumption correct?

Sorry for all the questions but any and all help will be greatly appreciated.
Thank you.
tClarke

nah you'll be fine all together. you may throw a code for the EGR, but i wouldn't sweat it.

So with the free flowing exhaust and lack of EGR I def. should have more power?

yes

2.5 isnt an overkill. i, along with lots of other people run 3in on n/a ka's. test pipe is up to you. your not really gonna see any gains compared to a high flow cat.

Thanks for all the help, but another question, how much hp/tq, number wise, increase should I expect? All I have on it is an Injen intake, headers, test pipe, and cat back.

go to a dyno shop..if you want exact numbers of torque, hp, and a readout of your powerband the dyno shop is the only place to be.