I know there are a few threads on 16g vs 20g but I wanted your opinions on my setup weather a 20G would be a gain or not worth the hassle of swapping

current turbo is a Port matched MHI Evo 3 16G

I have a 20G turbo rebuilt sitting on the shelf from a different build but I would need to get a external wastegate to use it.

I am not sure with 20G I have because it has been shaved smooth if I post a pic can you tell me witch one it may be.

thanks guys for your opinions

What are your goals?

Your goals will determine whether or not it's worth it.

Seems like you have the mods to support the 20g already, so I say why not? Bigger is always better . But your spool time is going to be slower but on the highway the car is going to feel alive. Another thing to ask yourself are the pushing the 16g to the limits? If not try turning the boost up and see how happy you are with it then decide if you want to take the time to swap them over.

thanks guys

my goals would probably be 500HP or more to reach 10.5 sec 1/4

the car is around 430ish and like 11..3 sec 1/4

my boost gauge says 30psi do you think I am really getting 30 psi out of a 16G

here is what I have on the shelf

We had someone make 414 hp(e85) on the 20g with tdo5h turbine and 449 (pump gas 28psi) on the tdo6sl2 20g with 7 blade billet wheel.
i had someone make 364 hp at 24 psi on pump. it seems like they get get close to the 400 hp mark with the tdo5h shaft being the limiting factor.

well it sounds like maybe the 20G will not quite get me were I want to be

any opinions on maybe what turbo I should use to get me to my goal or 10.5 sec 1/4

11.3 on a 16g is very good. As far as 30psi, you're SD. I wouldn't be using a boost gauge to determine boost, I'd be using the MAP sensor. More HP more problems.... Your 255 walbro is probably pretty close to being maxed out now. Any more HP and you're going to need a bigger pump. Also are you on street tires? Bigger turbo=more wheelspin=harder to launch. I went from an 8.2@86 on an FP Green last year (1/8mi) around 430HP to 7.99@94 so far this year on my FP Black (~575HP). I'm having trouble cutting 60's with this bigger turbo, therefore am nowhere close to my goal of 6.99 1/8mi. 20g may not be worth your effort. Next logical step in my eyes for a quick spooling 10sec turbo would be an HTA Green or an HX35 or a BW S256. Take all of that with a grain of salt as your 10.5 sec 1/4mi goal is also mine and I'm nowhere close to it .

I looked at your profile and it is very similar to mine. I was running a bastard 20G, stock cams before I went with my build and my goal is a 10.99 or better street car so I am running a HX40 now and hoping to get the car running very soon. Motor went in this last weekend so now its just getting my SD hooked up (flex fuel too) and the water/meth for my 10:1 motor. 6 bolt, kiggly girdle, arp main, rod and head studs, Evo 3 intake, FP race exhaust manifold (its all in my profile). Hopefully some others will chime in too. Looking at bigdnno98's comments I may need to go up to the Wally 450, since I have the 255 currently. Thanks bigdnno98!

No problem. I think I'm getting ready to sell this FP Black and go to something smaller. I'm giving up on this 10.99 goal. Now I just want a fun street car that makes peak boost before 5500RPMs. Ideally I'd love to find someone to trade their 68HTA for this FP Black.

I may be over shooting my goal to because really, I just want to drive my fast street car again after being down for a year....I really miss the little car and its stealth look that eats up 5.0's and such.