i got shop to put on the gears for 200 dollars but they are putting all parts new high performance so by how much will my ets drop with 3.42 gears and a set of under drive pulley like .4?

it depends, when i went from 3.08 to 3.42 my ET did not change at all. although my MPH went up by 2, so i could have just been a bad night at the track for me.

Some poeple have seen as high as .5 sec drop but that is with a 3.73 from 2.73 swap. Depends on what motor you have and what size gears you just replaced. You could easily see.4 with the right track conditions.

well i prder some parts from spohn suspension will this help me drop my ets?
lca's, panhard bar and streeing brace?and plus the 3.42 gears i will put in the year off the year

the LCAs will, a torque arm will really help also. the panhard, and steering brace won't really effect ET. they are more of a cornering peice. also LCA brackets will really help the car bite. make sure you have sticky tires too.

how hard is it to put on the brackets?i know u gotta weld them what do u do with the ones on the rear end now?

they fit over the ones in the rear, you don't remove anything. they are pretty easy, you should be able to take them to an exaust shop and have them weld them in for cheap.

NOTE: DO NOT INSTALL THEM THEN TRY TO DRIVE TO THE SHOP

You may wanna think about a higher stall as well, it will compliment your gears and headers

You will see a bigger improvement of your MPH then your ET with gears, and Underdrive pulleys wont change anything.

what stall should i get?what u mean they just side over the original one?so i buy them and put them on and weld them over the stock ones?

yes

and what does this do?what will see from the brackets?

it increases the anti-squat of the rear suspension, you can get 100% or more anti squate in the rear end, which drives the rear wheels into the ground .. thus more traction. but if handling is a concer, roll steer will become and issue.

what u mean by this?(but if handling is a concer, roll steer will become and issue.)