RB5_245

Does anyone have the compressor maps for 16G and 20G wheels? I think i have the one for the 16G but would like to compare.

Also the VF35 turbo, i don't know what compressor wheel i has but i would like to see the map.

Cheers, Dave.

Edited to say, i found the Maps but do they vary depending on turbine side? i wouldn't have thought so, then does that mean the TD06 20G map will be good for a TD05/06 20G hybrid?

Also is it 13G we have on the TD04 MY99?

Cheers again, Dave

[Edited by RB5_245 - 11/7/2003 4:43:38 PM]

john banks

No easily available maps for VF35 but it is small and is most comfortable in the low 300s BHP.

Yes MY99 is a 13G.

20G hybrids sold in the UK tend to have the original turbine and housing off a TD05. This is capable of a comfortable 400-440 BHP at least.

Turbine maps are not widely published. But the turbine has the greater effect on spool up and lag than the compressor.

EMS

I'll try to get some newer IHI maps (VF30/34/35).

I like these turbo's!!! (the 35 the most, as I can't see that the "small" turbine housing is too restrictive) In my oppinion it's the best match for this compressor on a 2.0 Subaru.

Mark.

RB5_245

Cheers john, Do you get a lot of problems with boost surge on the 20G at low revs/full throttle when trying to run say above 18psi. It looks to me like it's a bit big (for reasonable power ). How does the standard ecu cope with this, do you need daws to make it work from low revs?

john banks

It is OK at 19-20 PSI on most cars, you can use the ECU or a Dawes or EBC.

The VF35 also flutters a bit I've found if you try to pull more than 19 PSI before 4000 RPM, certainly this was an issue on the STi 7 and also on STi 5 with VF34.

Personally I also like the VF35, but prefer the TD05 16G on a 2.0. It only spools up about 100 RPM later, but about 15% more flow potential I would estimate. The 20G is about 200 RPM later still, but still 1 bar at 3000 RPM typically, and can flow about 35% more than a VF35. I will happily exchange 300 RPM spool up for about 100 BHP The usable strong rev range is extended so if you are prepared to hold gears right to the red line you may benefit more. With a VF35 it obviously runs out of puff over 6000 RPM. The 20G slams into the rev limiter and you'd better be ready.

EMS

I mapped one VF35 (MY99) car (with STi MY02 TMIC) that outperformed every TD05 (and VF23) I've seen without any problem! I didn't see any TD05 car here that performed better than a VF23... The TD05/20G is a different story! I drove one car with it at only 1.0 bar and it was (very) good. I have to map a MY99 with this turbo in the near future. I like that one. I prefer the VF35 over the (front entry) TD05!

Mark.

john banks

Since the only thing we can compare is a Delta Dash road dyno... the bar is 320 WHP on a TD05 from my results, average of two directions, without an exhaust manifold, no water injection but using octane booster, best was about 300 WHP without the booster. Can a VF35 without an exhaust manifold and without STi heads get anywhere near this?

john banks

Here is the example STi 7 with manifold DDF from the Ecutek site (one of yours) vs my MY00 without manifold. I've used the extra boost capacity of the TD05 (because you can with the TD05 and it makes up for no manifold). Maybe the STi heads gives the sorts of gains of the octane booster I was using? Even if not, a TD05 without booster would still beat the VF35 comfortably.... It is not really a head to head between the turbos, but they are some figures to start with. Not sure if the STi 7 here had a FMIC which would maybe a bit unfair if it did not.

We have both used 125kg on top of the official kerb weight, drag on the STi 7 is 0.37 vs 0.35 for the MY00. Gearing is very similar - UK car in 3rd, STi in 4th, so UK car is 7% lower geared here.

Any better results from a VF35 car?

I'm surprised at your report, the VF34/5 I've found OK, but nothing like a TD05 on full song.

[Edited by john banks - 11/7/2003 9:29:17 PM]

T-uk

john,

could it also not be that the VF35 is a nicer turbo when standard injectors/fpr and possibly inlet are used.

we both know that with my own car , if I changed these even without booster I could run more top end boost and gain probably another 20wheel power on delta dash.

iirc. we are well inside the td05 compressor map with the boost I run , perhaps the VF35 at the same boost, might be on the edge of the map but still perform better in this situation?.

john banks

"if I changed these even without booster I could run more top end boost and gain probably another 20wheel power on delta dash"

You could just run more top end boost anyway, but you don't want me to You don't need injectors to do that. Inlet pipe is probably worth a couple of horsies at most?

It is all down to personal preference, I don't think the VF35 is big enough