I've been at the crossroads for quite some time between the BR 20G-9 vs. BR GT35R turbo upgrade for my '03 VIII. Just when I was certain that the GT35R was the prime candidate, I come across this thread started by Mr. Buschur himself about the 20G-9 pulling 2.14 seconds faster in third gear between 3K-7K RPM than the GT35R. I think my head's been in the ground because I've focused only on power (dyno) numbers. I'm looking for some serious unbiased advice here. I know that I can get the two-stage launch ability through Dynoflash meaning that either the 20G-9 or the GT35R would already be spooled and ready to be unleashed. I don't go to the track very often and I'm hoping to fall somewhere in the 350-400whp mark until I finish paying the car off and then I want to shoot for the 450-500whp mark. Does the 20G-9 have the capability of reaching 450-500whp or should I spend the $1600 difference and purchase the GT35R from the "get-go"?

Thanks

 

Tough decision huh. I went through the same thing . Just look at my sig and you'll see the path I took .

 

Yeah I think the 20g is capable of that power, but you'll more than likely need to run meth or a race fuel of some sort. You'll need more mods than the ones in your sig to get 450-500 whp though.

 

450-500 WHP from a 20G-9, are you sure about that? Is it physically capable of flowing that much air? I was torn between the BB 50 Trim and 20G-9 and ended up getting the 50 Trim, partly because upgrading to a bigger turbo (e.g. 35R) is simple and cheap this way.

 

You would more than likely need everything done though, like cams, intake manifold, race head and internals lol.... and the gas of course higher octane

 

That was from 3K, the GT35 doesn't spool at 3K, it spools up at 4200 and will hold boost to 9000+ RPM's. The Buschur 20G is very nice and gives you torque, but the GT35R will make well over 100WHP more and have better topend by far, but you give up the low end. The 35R will hold over 35PSI if you ask it while the 20G cannot. On a stock 03 Evo block expect to make 450WHP max on race gas with a 20G, the GT35R can almost hit that on pump gas, on race gas you can get 550+WHP on the GT35R having the stock bottom end bing your limit, if you built a 2.0 motor expect well past 600WHP with a GT35R.

The 20G is an AWESOME street turbo, losing very little spoolup so your gona keep all your low end torque. If you just going to run pump gas, stick with the 20G, it;ll make great power and is very streetable. Running race gas and Alky the GT35R will make BIG BIG power for sure but it still lags.

 

Buscherpowered on this site ran an 11.3 at the track with a 20g on a stroker motor, he has more in it as he was only running 23lbs of boost on race gas.

On an 03 you will need to shell out much more cash than on a ix in my opinion.
I had AEM ems/turbo back/DP/ BC/HFC- and put out 333/333 on TTR dyno.

If I went the 35r route I would have to build my car to rev to 9k to take advantage of the power band.

 

You should sit in a car with the 35R... im sure it would change your mind once the turbo starts to sing. My car is tuned at 29psi and it is scary fast... Dont worry about turbo lag and when full boost hits. Once it reaches 4000rpm and above it pulls like crazy and just doesnt stop....remember anything over 4k the turbo is pushing so much more power so even if your not at full boost the car is still hauling ***.... Before I bought the 35R I kept looking at dyno graphs to see when full boost hits but when you actually drive it you will know full boost dont mean anything....to me it doesnt. Yes a smaller turbo will get a head jump if you are both at 3k rpm and start to go at it but in about 3 seconds time you will destroy him.

What is your goal and what is it you want from your car?
1. "dam this turbo is fast" get the 20g-9
2.OMFG holy $hit- get the 35R

this is my opinion.

BTW I have not been in a Evo with the 20-9 but my friend does have the HKS 3037 turbo on his Evo 8.

 

35/37r Ftw.

 

Here is another overview from David himself:


https://www.evolutionm.net/forums/sh...d.php?t=169638

 

On a serious note... when racing, when do you *ever* start at 3k rpm... from a roll or dig? Buschur's test was nice to compare the lag and power of both turbos... but not exactly for realistic use.

 

from a roll.. btw that was just an example if you were to run both cars at 3k rpm.

 

I was worried about the lag of a Gt35R because i'd never been in a car with one. I decided to go with it anyway (was originally going with a GT30), and i'm glad I did. The lag is not nearly as bad as its made out to be. No way i'd go back to a smaller turbo.

 

I disagree with the above. It has been suggested (pretty sure by Buschur himself but not 100% positive) that the 20g will not make substantially more power on pump gas than a 10.5 16g, it will spool a little slower too. The 20g will however hold higher boost better when run on race gas or alky/meth injection, and that is where it will shine over the 16g.

To the above poster, I would wait until we see more 20g cars running at the track before making a decision.

 

Do you have an AEM EMS? If so I think that is key to getting decent spool up on a gt35r turbo. So I think that is something that the original poster should consider in his $1600 dollar difference.