"stage 2" VF40 to VF52, stock fuel.

Has anyone that's done this care to share their impressions? I've got a catless turbo back and a pretty conservative tune on the car at the moment. The mod bug is starting to rear it's ugly head again and I want a bit more power. I'm looking around and it seems like the VF52 + an aftermarket topmount can get some pretty decent numbers (280-290whp), but then it also seems like there's these super stock turbo cars at 270/280whp. These could very well be inflated numbers though, depending on the dyno.
I guess my question here is whether or not a more aggressively tuned VF40 car with more bolt ons (tmic/headers/intake) will be as quick as a VF52 car with a catless UP/DP and bigger topmount but on the stock fuel system. There's a lot of numbers floating around and I'd like to hear some real world experiences.

i went stage 2 with a BNR 16g turbo, FMIC, DW fuel pump, GoFastBits Manual boost control. Intake, pro road tune and up and down pipe and stock exhaust, just about 325, i could go for more but dont want to risk blowing the 5eat till i do the valve body upgrade.

Why focus on the numbers, then? Why not instead focus on what's needed? You need a tmic if you don't already have one, and you might as well get the fuel pump. You're not going to flow enough through the 40 to utilize the headers or intake. If you're targeting 300whp, a 40 won't get you there. Plus, in order to get close you are pushing more boost than your turbo would like to see.. did you read the turbo wiki thread?

Originally Posted by captainobvious

i went stage 2 with a BNR 16g turbo, FMIC, DW fuel pump, GoFastBits Manual boost control. Intake, pro road tune and up and down pipe and stock exhaust, just about 325, i could go for more but dont want to risk blowing the 5eat till i do the valve body upgrade.

Fyi.. you're not stage-2 if you have an upgraded turbo..

This might help. the 52 car had a stock tmic fwiw. Sea level cool air 93octE10 blah blah blah

Originally Posted by Nolmers06LGT

Why focus on the numbers, then? Why not instead focus on what's needed? You need a tmic if you don't already have one, and you might as well get the fuel pump. You're not going to flow enough through the 40 to utilize the headers or intake. If you're targeting 300whp, a 40 won't get you there. Plus, in order to get close you are pushing more boost than your turbo would like to see.. did you read the turbo wiki thread?

It's hard to focus on anything but numbers when I don't have a VF52 on my car to really feel it. I'm not going for any magical number, because if I wanted 300whp all I have to do is find the right dyno.

I've just seen a lot of guys posting up 40 numbers what would lead one to believe that it's an extremely capable turbo compared to the 52 on a stock fuel system, so I thought I'd ask for individual's thoughts and experiences, rather than focus on the numbers. That's all.


And thanks NRW, I searched a bit and never came across a comparison on the same dyno. The 52 is on stock injectors, correct?

Yessir stock fuel. The lack of a aftermarket intercooler is holding it back a bit along with a EBCS.

Both on the same dyno, though different days. Both are 5mt's and actually wagons now that I think of it lol

It's not just the end result, it's the way they make power. The VF40 may make say 260 whp and 280 wtq, but it will die off in the high rpms. You get that initial punch and it tapers. A VF52, or BNR16g which I am installing, will make the same power and more, and they won't die off. It will be a nice, continuous pull. Boost will taper slightly on the higher rpms due to the stock fuel system, but it will far out power the VF40.

It's about the power under the curve, and the VF40 can't compare. It peaks quickly and dies off, a VF52 or BNR 16 peak quick and maintain power. A maxed out VF40 would lose a race to the others since if they had the same power it would taper.

Originally Posted by DansSpace

It's hard to focus on anything but numbers when I don't have a VF52 on my car to really feel it. I'm not going for any magical number, because if I wanted 300whp all I have to do is find the right dyno.

I've just seen a lot of guys posting up 40 numbers what would lead one to believe that it's an extremely capable turbo compared to the 52 on a stock fuel system, so I thought I'd ask for individual's thoughts and experiences, rather than focus on the numbers. That's all.


And thanks NRW, I searched a bit and never came across a comparison on the same dyno. The 52 is on stock injectors, correct?

My point was just that hp numbers are deceiving.. there may be guys with 40s putting down 52 numbers, but I'm not sure you can expect reliability..

Why push a small turbo so hard when you can push another turbo to the same power level without stressing it?

Originally Posted by Nolmers06LGT

My point was just that hp numbers are deceiving.. there may be guys with 40s putting down 52 numbers, but I'm not sure you can expect reliability..

Why push a small turbo so hard when you can push another turbo to the same power level without stressing it?

Oh, I'm definitely leaning towards the 52 as it is anyways.

Do you have an aftermarket tmic or bpv yet?

Originally Posted by Nolmers06LGT

Do you have an aftermarket tmic or bpv yet?

I'm planning on getting both to go along with the turbo

Get yourself a fuel pump if you haven't already. DW65c is nice, GRB STi item also is plenty.

Bullet-proofing your stock TMIC will certainly suffice for a VF52 setup--you'll likely see very little gain from going with an aftermarket unit, maybe a bit more if you go process west but I haven't seen a direct comparison back-to-back. Front mount will likely net you a bit more at the expense of additional piping and hassle.

Originally Posted by BarManBean

Bullet-proofing your stock TMIC will certainly suffice for a VF52 setup--you'll likely see very little gain from going with an aftermarket unit, maybe a bit more if you go process west but I haven't seen a direct comparison back-to-back. Front mount will likely net you a bit more at the expense of additional piping and hassle.

I'm planning to bulletproof mine (Thanks BMB) in prep for a vf52. As my car sits right now, I'm pulling roughly 240g/s with a stg 2 tune on a vf40. I know its fairly inaccurate to base hp from g/s, but its the only estimate I have. That said, I should be putting down somewhere close to 270whp.

If you're planning a turbo upgrade, you should make sure your engine can handle it by buttoning down all of the failure points through the system. IE the tmic (will leak over 17psi), bpv (may or may not leak at 52 boost levels), fuel pump (so you don't risk running lean by not being able to supply enough fuel).

I've also heard the turbo inlet should be swapped out, as well as oil supply lines, and an EBC will help control boost.

You can upgrade the turbo without doing these things, but you risk boost leaks, etc, and run the risk of detonation. IMO, its not worth the risk.