I will make it simple,

V6 sti Ra
Full 3" RCM system (decat)
Standard headers
550cc injectors/uprated pump and parallel rails.
Large cone filter
STI8 TMIC
Simtek ecu

What turbo do I run?

Want to keep it to a VF or TD due to running the ALS, which will reduce its life anyway. So needs to be common unit.

Im looking at td o5-18g, VF34 or VF 35

Would like around the 350bhp figure.

From what I read, the 35 will run out of puff for anything over 350, as will the 34.
Anyone confirm this?

Whats the pros and cons of the 05-18g?

Also, what gain will I get with the headers being changed at the same time? Should I go semi or equal or port the std ones?

Thanks in advance

Jamie

 

Your 550s are the limiting factor i.e. around the 400bhp mark.

So a 20g, 321H, Billet SC40 - if you want near 400!

I think harvey also does another affordable 400 turbo that is more likely to hit 400 than the 20g given like for like supp mods. Don't know what it's called though...

18g would be a good choice if happy with c.360-380. You should make the latter figure on your engine/mods. 18g spools a bit earlier than the 20g - prob at 3.4-3.5k rpm, with harvey's ported OEM headers and matched uppipe (these help gain c.150-300rpm in spool alone! ).

If you want just 350+ with max spool, then the VF34... or Billet SC36...

 

As said...Harvey is very much worth a call on this, his turbos are very good and excellent VFM...

My spec is very similar to your own, on a V5 Type R, and Harvey sorted me out a 400bhp capable turbo that has no more lag than the original VF28.

 

s5ooob, what is that turbo called - I'm well interested!

 

Joz, I believe Harvey calls it his HS380...if you do a search on here theres a few graphs and some info kicking about....

IIRC it was developed on harvey's own standard engined STi 3 and made 390bhp on this car with a STi8 TMIC, then 407bhp with a FMIC fitted. I think boost was around 1.5bar.

I've just had a forged engine built and will be running mine at full tilt, boost wise, when it gets mapped in a couple of weeks...should be interesting

 

From what you say the VF34 or TD05 18G would be a good choice. The VF35 is probably not a big enough step up from what you already have. There are secondhand VF34 about just ensure it is a good one or a new TD05 18G, ported exhaust inlet, oil drain, water pipes and uprated actuator all for £675 currently. The 18G is a hardy turbo so anti lag is not an issue if that is your thing.
Ported headers and matched uppipe all DEI wrapped (£369) work well with any of the above turbos and show a definate improvement. Without more expense it is not worth going to tubular headers at this stage.

 

Harvey,
Thanks for the reply.

Sent you a mail as I need a FMIC now and a few other bits.

 

I just purchased Harveys version of the Td05 18G and stock ported headers... had those all mapped up yesterday and they are an absolutely awesome choice! great surge of power from the turbo all the way to red line and with the headers i have an massive bucket or torque at my disposal!

Highly recommended set up!

 

After having spent the day looking into many options, Im now looking to go for Harveys Front mount instead of the Newage TMIC.

Also going to look at his ported headers as they are mush better than I could ever have imagined.

Then the 18g is on the back burner as I think the 20g could be the one for me.
Sent Harvey an email today anyway, so wil;l see what he comes back with.

Worst situation is I stick the FMIC on along with the 550's, full 3" and ported headers, get Andy to stick the Simtek on and change the turbo at a later date once im convinced I know what I need.

Work in progress

As I say, will see what Harvey says first

Thanks

Jamie

 

If your going for the 20G Jamie 550's might not cut it, I maxed out a set of 550's last week getting my 20G mapped from Andy.

buy big, buy once

 

Contact mark at lateral performance regarding injectors, he can modify your STD 440cc's to flow far more than 550! Think they end up circa 800cc capable. I had some done and used them on my type r (2.5 and 20g)

 

Dunk, if one was to have a Fuelab FPR added to the 550s and pressure upped to c.4+ bar, then surely there would be enough fuelling to see the potential max form the 20g?

I ask this, as these are my next mods to fit (+ FMIC of course)...

 

Nope, mine has a FPR fitted and think fuel pressure was set at around 4K and I still maxed the 550's out, being honest I have two maps (Simtek) one on Vpower, the other meth + vpower, I'm not sure if I only maxed out the 550's on the meth map or on both of them.

 

I'm a little miffed here. I was advised by a well known specialist to swap my 740s to 550s if I was going to run a 20g.

I thought 550s could manage 390-420bhp...... on std 3bar?!!!

 

550s on V-Power will max out somewhere close to 390-400 bhp. Sometimes a little more, sometimes a little less. The actual injectors in use will be significant. Some flow more than others or it may be they are rated at different pressures. 550s tend to max out around the ability of my 05 20G turbos.
4 bar map pressure is very high.
If you plan to run Methanol and want to exceed 400 bhp then obviously you need injectors bigger than 550cc

 

Cheers harv.

No, intend to get mapped on V-Power only.

Assuming my 550s and 20g are 'quality' items (), would you expect the 550s not max out before the 20g does - if the mapper sets the FPR to around 3.5bar? (I meant to say 3.5, not 4+ ).

 

My injectors where at 98% on a Tdo5 18g with stock fuel pressure at 1.5bar. It might give you an idea of the room you have to play with

 

It will be interesting to get a power figure for your car on a rolling road but tht sounds like a good result and suggests that the 20G needs more than 550 injectors. I only say the 18G is a 360 bhp turbo and the 20G 380-390 but some guys have reported 380 bhp on the 18G and 405/407 and 409 bhp on the 20G. Obviously a lot depends on supporting mods and the actual injectors. The turbos are all the same ie. all 18G are the same as each other and all 20G are the same as each other and both run the same actuator. The 18G has had a billet wheel for the last 10 months but there is no obvious performance difference with the pre billet wheel and both are exactly the same design.