well I been giving it some thought lately and im gonna turbo my 90 gta.
here is the list of mods:

power train:
_383 eagle rot assembly, srp pistons
_tfs twisted wedge g1 heads(extensive porting flowed 290@.550 lift on independent bench)
_hsr heavily ported as well to 1206 gasket, holley 58mm tb
_cam .550 lift 245-250 dur @.050(will retain this cam for now)
_ebl p4 flash 7730 computer.
_700r4 fully built reverse manual 2800 stall.
_moser 12 bolt 3.73 gear

this is going to be a street/strip car only used on weekends....car currently runs 11.40@117-118 on motor, compression is 10.5-1, going to put taller head gaskets to lower comp to 9.2 to1
will run 94 octane as my only fuel option, I been looking at 76mm and 80mm turbos and I came across this unit gt45r 80mm
here is the ebay link:

http://www.ebay.com/itm/CXRacing-GT45-GT45R-Ball-Bearing-Turbo-Charger-80mm-wheel-T4-1-15AR-Big-Power-/181106806132?pt=Motors_Car_Truck_Parts_Accessories&hash=item2a2ace8d74&vxp=mtr
I know some of my friends are running the borg warner s400sx4 80mm trouble free.
the unit im looking at its a lil cheaper, but I wouldn't mind to pay extra if this one is that much better.
now my goals..lol..want to run mid 9's in the 1/4 I know I will be making changes like bigger injectors, 340lph aeromotive pump etc(currently have 255 walboro pump).
which turbo should I go with?
car weights 3500lbs with me...will be lighting up a bit as im putting pa k member and all the heater stuff will be gone.

 

With that much already into the engine I would go with the BW instead of the China Garrett knock off. I would start with the 80mm Comp wheel.
Will gaskets give a decent quench at 9:1 compression? Sounds like it needs heads or pistons.

 

I think it won't be to bad for quench, when motor was built we kept in mind that it will be turbo charged some day

well I guess im gonna go with the B/W s400sx4
what air to air intercooler anyone can suggest?

 

Get it close to mid high 9's comp with gasket but dont go too high on quench height if you can help it. don't worry to much about the comp and just keep it intercooled well and run good gas when you crank it up to run 9's

Keep boost lower on street for pump gas driving. Mix race gas at the track to be safe

Go much higher on converter. Actually get a real trans first then i'd say 3800 stall atleast with that cam and a good turbo hotside. High stall allows footbrake higher to build boost, if you dont get a transbrake. Good T4 turbine will have boost threshold around 3500-3800. Stall around that will help response. If you are slightly high on compression say closer to 10:1 after gasket swap that doesnt totally kill quench height then you want to spool turbo higher rpm. You dont want to make power down low or midrange rpms wise, that creates alot more cylinder pressure. You want to push torque up higher rpm range, helps keep it less detonation prone

With that big cam and even closer to 10:1 you may be ok on pump gas. Dcr is lower so that does help. I ran 24 psi on straight pump gas at 9:1. 10:1 should handle 10-15 i would think with big cam and make a easy 650-700 whp which will do 9's et.
All depends if you get the car to launch well in boost else it will run high mph with no et like mine has past few years lol

BW s400 stuff could do it. 75-80 mm single is a good starting point

 

I already need a stall change with this combo..lol...so with the turbo defiantly I will change stall...I want to keep the 700r4 I just love the lock up when I cruise...all tho that low first gear will help to build boost quick can also make it a burn out monster....I want to run drag radials wich is what I run now...I have every susp mod done to the car it works good...going 1.4 on the sixty with nitrous so with better stall and turbo I expect 1.3 shorts..i guess ams500 will be my best friend.
thanks for your input....what size cooler should I be looking for?

 

go with the bw 80mm. ditch the 700 trans, do a th400 and a 3.23ish gear.

 

To 60 ft you need to leave spooled up in boost which requires a transbrake. At that power i do not see a 700r4 lasting long. And with turbo power, and that steep gearing, i dont see it hooking well enough. Turbo cars usually leave softer than comparable nitrous cars so just getting 1.4's would be good for now imo

4l80e is only option if you need lockup. But big trans to fit in these cars. Expensive to.

Cooler go for the biggest you can fit rated for over your hp level

 

thanks for the response....my friend has 4.6 stang with 80mm bw turbo he has no brake but rocks a 4000 ptc stall...he's been able to cut 1.3 shorts just footbraking it...its ironic because I have a th400 fully built as a spare on my shop....I know the th400 will take that power all day....but my issue is when I cruise, I go for 2-3 hour cruise sometimes all night as I live in the country I need to travel lil...and 3500 stall its going to be one hot trans cruising..no matter what gear I run...4l80e I like it...but ridiculously priced tho...lol.
I want to keep the build under 6500, and im doing all work myself.
i never used those air to air from ebay...are they even worth a look or i should just stick to pt or chisseled etc, the known brands?