well I am still dealing with lag issues so I need to go smaller .I do truck racing I only use first and second gear so I am never reaching full spool .right now I have a t70 ebay turbo its a .70 cold .84 hot .on a 1/2 bridge 13b-re .I got a turbo off my buddy for free that was just rebuilt its an air research .42 cold .42 hot I relize I will lose top end but will this work or should I try something else .I really dont want to spend alot of money right now plus I am beating most ecerything as it is but I want more out of the hole

 

Smaller A/R is a good way to increase spoolup. But, the bridgeports can't take to small a turbo. When the wastegate starts opening that is the begining of the end to you power. Exhaust pressure will be climbing faster than intake pressure. Shortening intake piping length is good for reducing lag too. You may want to go water-air or topmount intercooler if you have to. My 2 cents. Good luck.