Need replacement turbo advice for 2005 GT

Stock turbo blew - shop offered IHI VF46 to replace stock IHI V40 series, saying it is exact bolt on replacement with no mods needed.

 

Any comments on the above?

 

Gary McCormick

the VF52 is a bolt on too if you decided that you wanted to go faster later on. It would need supporting mods to make more power though

My question is whether IHI 46 is direct bolt-on with no issues

Yes, VF46 will bolt on and work just like the stock unit.

Thank you both

Revive and old thread because there's nothing like searching..haha

 

So if/when my turbo blows up, I can replace it with a VF46 or even a VF52. Would I be correct in saying an all stock car with a VF46 would be faster than an all stock car with the V40? And if a person is running Cobb AP Stage II with the stock turbo but later added the VF52, you would see an even greater difference in power even on top end?

Revive and old thread because there's nothing like searching..haha

 

So if/when my turbo blows up, I can replace it with a VF46 or even a VF52. Would I be correct in saying an all stock car with a VF46 would be faster than an all stock car with the V40? And if a person is running Cobb AP Stage II with the stock turbo but later added the VF52, you would see an even greater difference in power even on top end?

 

You will see less torque at the low end.

So if/when my turbo blows up,

 

key is not letting it if/when. preventative.....replace before it goes. do your regular oil changes. remove the banjo filter (I never did and mine have been fine). on my 3rd turbo, each lasted me about 100k or so before I swapped them out.

key is not letting it if/when. preventative.....replace before it goes. do your regular oil changes. remove the banjo filter (I never did and mine have been fine). on my 3rd turbo, each lasted me about 100k or so before I swapped them out.

 

Good info there.

 

I replaced mine before it blew, mine gave me warning, Learn what your turbo sounds like, when the sound changes, replace it. Or at least check it out.

Still running my original VF-40. Maybe replace it some day:rolleyes:

Mike

remove the banjo filter (I never did and mine have been fine).

 

 

Now there's something I'd like a definitive answer on. I've read so many contradictory threads/posts about removing it or not removing it.

My first turbo went out at 58K. I now have approx 122K on the next one so that's 64K on the replacement. I always took my car to the suby dealer every 3K for an oil change.

 

I've considered having it removed. Does anyone have a lot of miles on their car after removing it? I mean like 50K plus with NO issues.

My turbo is getting close to 30,000 with no banjo filter. When I did the new short block I had the machine shop remove the front filter too.

You'll never get a correct answer on the banjo bolt filter. Some people report them fairly clogged (especially after blowing a turbo). Lots of people remove to inspect and report very clean.

 

Also, VF46 is a stock equivalent replacement. A VF52 requires a modified tune to run properly, which is a major difference.

You'll never get a correct answer on the banjo bolt filter. Some people report them fairly clogged (especially after blowing a turbo). Lots of people remove to inspect and report very clean.

 

Also, VF46 is a stock equivalent replacement. A VF52 requires a modified tune to run properly, which is a major difference.

 

 

Hmmm, a VF46. Would have to perform some better than the VF40 and sounds like I could keep my Cobb AP.

I checked with a company yesterday on the VF52 and they said I would need bigger injectors, 650cc I think, and in addition to the Cobb AP, I would also need a Protune.

Sounds like they would add a specific tune to my Cobb AP for the VF52 turbo??

Hmmm, a VF46. Would have to perform some better than the VF40 and sounds like I could keep my Cobb AP.

I checked with a company yesterday on the VF52 and they said I would need bigger injectors, 650cc I think, and in addition to the Cobb AP, I would also need a Protune.

Sounds like they would add a specific tune to my Cobb AP for the VF52 turbo??

 

You can get more power out of the VF52 by upgrading injectors/fuel pump, but it's not a requirement. You SHOULD get a pro tune, and yes the tuner would add a map to your AP. There are plenty of guys successfully running a VF52 w/ stock fueling. The only requirement is that boost tapers toward redline to prevent lean conditions, whereas upgrading the fuel pump/injectors would provide more than enough fuel for the 52.

My vf52 has al most 30,000 miles on stock fueling, it's great for a DD. My Tuner loaded his custom map on to my Cobb AP v2.

Hmmm, a VF46. Would have to perform some better than the VF40 and sounds like I could keep my Cobb AP.

I checked with a company yesterday on the VF52 and they said I would need bigger injectors, 650cc I think, and in addition to the Cobb AP, I would also need a Protune.

Sounds like they would add a specific tune to my Cobb AP for the VF52 turbo??

 

Ahh, google is my good friend. Found a couple threads saying the VF46 provides no significant power gains but may be a little more reliable.

Here is my tune/dyno on my stage 2 2005 with a vf46. I have boost graphed in relation to power output.

 

http://legacygt.com/forums/showthread.php/stg-2-ic-2005-auto-dyno-161609.html?t=161609

Here is my tune/dyno on my stage 2 2005 with a vf46. I have boost graphed in relation to power output.

 

http://legacygt.com/forums/showthread.php/stg-2-ic-2005-auto-dyno-161609.html?t=161609

 

 

That seems like an approximate 50hp increase at the crank as you're probably around 300 now?? I'm guessing a stock 05 LGT auto is somewhere around 210-215 at the wheels if you use a 15% reduction as a rule of thumb and I know that number varies.

Why does the graph say Stage 3 if you're running Stage 2?

They considered the intercooler replacement stage 3. It didn't affect the way they approached the tune. IIRC the losses are more than 15% on the auto. I think they typically show 185 to 190 at the wheels. Not sure if it helps but I asked them to be conservative.

They considered the intercooler replacement stage 3. It didn't affect the way they approached the tune. IIRC the losses are more than 15% on the auto. I think they typically show 185 to 190 at the wheels. Not sure if it helps but I asked them to be conservative.

 

Hmm so in reality the VF46 is a little different than the VF40.....

 

My Stage 2 VF40 (Up/Down Pipe & ECBS (Stock TMIC/Exhaust & 98K Miles) is @ 225 WHP / 291 TQ.

 

So looks like the VF46 is a little more HP but a lot less TQ?

 

Maybe that's due to tuning though - How's your A/F Look?

 

Not trying to start a battle - just trying to help understand the differences between the Turbos with comparable mods:cool:

Stock turbo blew - shop offered IHI VF46 to replace stock IHI V40 series, saying it is exact bolt on replacement with no mods needed.

 

Any comments on the above?

 

Gary McCormick

I decided to step outside the IHI turbos and chose a BNR G16 which I am ecstatically happy with. Its a really nice unit and Brian, the owner, is incredibly helpful. As soon as the bearings are really broken in (say 1K miles) I will take it down for a tune to Bren Tuning. So far I feel like it is a VAST improvement. Also put on a COBB uppipe. Thanks to Underdog Motorsports for all his help. Man knows his stuff.

 

Also, while gas mileage is not of major concern its up to 24.5mpg around town. No trip

data yet.