VF40 18g upgrade

First, anyone that has one of these just write a little something about what you think as in performance increase over the stock vf40, supporting mods you'd suggest (note if the mod is NECESSARY to run the 18g upgrade), and finally just an overall opinion of its performance. dyno sheets are welcome. Just trying to pool some info on this topic, seems like whatever info there is is pretty sparse and strewed all over the boards.

 

Any of you guys send your stock vf40's into blouch to have the mod done? Heard they do pretty good work with turbo upgrades and rebuilds.

 

-Jake

Comparing the VF40 18g to a stage 2 lgt, it seems to have better top end and also 3rd and 4th gear is where you'll notice a difference in performance over stock, from what Ive been told....

I had this upgrade for a whooping 6 months. It spools close to stock but top end is a little better. I picked up about 15whp over stage 2 with this mod, AVO 15lb actuator(better if you use an aftermarket BCS instead), Perrin TMIC and fuel pump. Main thing was the area under the curve was improved.

What I've heard is... "Spools like a 20g and holds boost like a 16g."

 

It seems to me that an 18g is better suited for a 2.0 liter.

What I've heard is... "Spools like a 20g and holds boost like a 16g."

You've heard wrong.

so whats the consensus then?

Also, I just read a thread about the wrx vf34 with an 18g wheel upgrade and the guy mentioned having an fmic, 740cc dw's, and an avo pump. curious as to whether or not they're necessary for the vf40 18g, or a bigger topmount or something? protune obviously (since im not too educated on opensource and self tuning just yet), but would there be anything else I absolutely NEED to pull this off?

Just get a VF52.

Just a little more top end was my experience...I could pull to 7k, not die at 6100. If that's all you want, it's fine (stock spool, etc.)--that's really all I wanted at that time. If you really want a moderate increase in power and don't mind losing a little bit of spool, I'd go bigger.

Interested...

 

VF52 is on order for me but still searching for decent comparisons. A VF40-18g doesn't sound too far off the 52. I'll be having Grimmspeed play around with the thing before I install it.

 

We'll se...

 

Ideal would be OEM fitment, VF52 spool, 20G top end. I can dream can't I

Are you guys talking the vf40-18g, where its just the 18g wheel on the exhaust side, and compressor side is still stock vf40? If that is the case I would say the vf52 is a better option.

 

I have a full td06-18g that was machined into a vf40 cover, so the hotside is from mitsubishi (bought the turbo used).

 

Yes, main difference is it doesn't fall on its face at 5000rpm like stage 2 used to. I can hit 20psi by 3300rpm, so it does spool slower than stock turbo, but that is the trade off with anything bigger than stock. Even a stage 2 vf52 will spool slower than a stage 2 vf40, if just slightly.

 

Right now my 18g is maxing at 22.5psi around 3900 and tapering to 18psi at redline. My vf40 was maxing at 18psi with my stg2 tune and boost fell hard toward redline. Overall I am happy with the 18g and I would say its a very nice daily drive turbo. I know its not the fastest, probably 300whp, but I like the fact that it keeps pulling through the whole rpm range.

I have a td06 18g as well, and I love it. Peak torque at 3300 rpms, and it pulls all the way til redline. The stock tmic couldnt even handle 16psi from the 18g until it blew apart so I would say tmic, and injectors are a must. But you would be dumb not to go with a catless up and down while you are at it.

But you would be dumb not to go with a catless up and down while you are at it.

Planning on snagging a perrin 1 piece single highflow cat down from fred beans (got an amazing deal on them going right now), and an HKS catless (obviously) up. The tdo6-18g sounds like just the turbo Im looking for, since my target whp is probably around 300-330 or so for now. Since theres already a problem with my stock vf40 (Link), I figured why not see whats available in the market with minimal accompanying mods. But it seems like the tdo6 18g needs all the supporting mods; tmic, pump, dw's. Dont know if I have all the dough for this now, especially since I'm throwing on the up and down and am going to need a good protune if I go the new turbo route. If not, I do have my ap to load a stage 2 rt map, save some cash there and put my $500 I paid for the ap to work. But Im somewhat paranoid about that thing now, and you'll see why if you read that thread I linked above...

A TD06 18g and a VF40 with an 18g comp wheel are two completely different turbos..OP...which one are you asking about?

well i started off asking about the vf40 18g upgrade but now thats lead into strong consideration of the tdo6 18g.

Consensus is that hybrid IHI turbos (especially vf40's) suck balls and are not reliable at all. True story. Don't waste your time. Better off just getting a tdo5h 18G.

is there a specific mitsu turbo of their 18g family i should be leaning towards? i.e. either tdo6, tdo5. not too fermiliar with the deifferences between the models.

tdo5 will spool slightly quicker but the tdo6 will make another 20whp or so. I had a TD05 and it spooled similar to my vf4018g but it made more power through the majority of the power band.

Consensus is that hybrid IHI turbos (especially vf40's) suck balls and are not reliable at all. True story. Don't waste your time. Better off just getting a tdo5h 18G.

 

No 100% true. Mine is dead reliable, makes huge torque, 17psi by 2850rpm, 19psi by 3000rpm. Huge power difference from 5000 to 6500.

 

Supporting mods;

 

Invidia catless DP

X02 FMIC

15 pound actuator

catless UP

K&N Typhoon

TDC tune

 

If you have a ver 1 AP I could put a package deal together for you with maps. I'm looking to go bigger.

I already have a v2 ap, would you be able to write something for that? May be interested in yours if your planning on upgrading soon. Really was looking to avoid having to upgrade the injectors and pump just yet, so I may hold off on the tdo5 18g.

My hybrid will tune fine with the stock fuel system at 19psi. If you go with a TDO5 or TD06 they are WRX type flanges and won't bolt up to a LGT top mount.

 

I don't know if a v1 map will work with a v2 AP. Check with Cobb.

tdo5 will spool slightly quicker but the tdo6 will make another 20whp or so. I had a TD05 and it spooled similar to my vf4018g but it made more power through the majority of the power band.

 

I thought you had the TD05-18 FP currently? (the one they discontinued for the HTA)

My hybrid will tune fine with the stock fuel system at 19psi. If you go with a TDO5 or TD06 they are WRX type flanges and won't bolt up to a LGT top mount.

 

I don't know if a v1 map will work with a v2 AP. Check with Cobb.

 

The reason the vf40-18g can work with the stock fuel system is the tiny hotside is still that of a vf40. It simply can't flow enough past around 5000rpm, so boost tapers like crazy toward redline. So, if you really want to stay stock fuel it is about your only option.

 

Personally I don't think even a vf52 should be run with stock fuel 05-06 cars with sidefeeds, maybe it would be ok on the 07-09 topfeed cars but I don't think the turbo could be used to its full potential.

 

Some td05/06 18gs and 20gs were made with the vf40 compressor cover, Deadbolt was the main supplier. I'm happy with the used one I picked up.

 

As for fuel, if you're going to a bigger turbo just do it. Its really not bad, pick up some used 650cc or 740cc for around $300 and a walbro for $80. I was all afraid of the walbro install and actually picked up 650cc thinking I could squeak by with the stock fuel pump. That didn't work so I had to get the walbro, and really the install was not bad (as long as you have a decent dremel).

The reason the vf40-18g can work with the stock fuel system is the tiny hotside is still that of a vf40. It simply can't flow enough past around 5000rpm, so boost tapers like crazy toward redline. So, if you really want to stay stock fuel it is about your only option.

 

My boost holds 19-18 to redline. We know about the tiny hotside but the hybrid doesn't fall off until 6500, not 5000. In fact, I was getting some boost creep with the addition of a catless DP. You could do some fuel mods and add alky injection and get more out of that turbo.

I thought you had the TD05-18 FP currently? (the one they discontinued for the HTA)

 

Nope, had the ultimate racing tdo5 18g with the modified flange to fit the 08 wrx/lgt. Before that I had THREE vf40/18g's from Deadbolt that failed collectively in less than 8K miles.

My boost holds 19-18 to redline. We know about the tiny hotside but the hybrid doesn't fall off until 6500, not 5000. In fact, I was getting some boost creep with the addition of a catless DP. You could do some fuel mods and add alky injection and get more out of that turbo.

 

GTTuner, are you still on stock injectors with boost at 18psi at redline? If so what are your IDC and do you know what kind MAF g/s you are pulling?