GDBSTi

Hi Chaps

Anyone give me advice on whether my friend should buy a VF23 or VF24. VF24 is US$100 less than VF24. Both 2nd hand 10 000miles.
His Specs: 2000Turbo, PPP,Turbo back 3" Catless exhaust,MRT Boost controller, Standard TMIC
Car used for Gymkhana's mostly 1st/2nd gear stuff, Hill Climbs (<140mph) sometimes and track racing (<140mph)sometimes.

Cheers
Rupert

john banks

1st/2nd stuff he would probably be better with the TD04 IMHO.

EMS

If it should be one of the 2nd hand turbo´s, I suggest the VF24 will better suit your needs. If it can be a new one, try the VF35!

Mark.

GDBSTi

John

If he kept using the TD04 what boost could he run within the efficiency range of the TD04 using a EBC. Keeping in mind the electronic boost controller will try to maintain set boost until the redline!!

Rupert

[Edited by GDBSTi - 5/17/2003 10:36:38 AM]

dhorwich

brand new IHI VF23 here for £650...!

Dan

[Edited by dhorwich - 5/17/2003 10:30:58 AM]

john banks

Rupert, the wastegate gets blown open by exhaust gas back pressure on most TD04s to limit them to about 1 bar at about 6000 RPM, some more, some less. On a decent EBC like an AVC-R it can be mapped by RPM anyway.

The only reason for sticking to the TD04 is if he is in events which required very little lag in 1st and 2nd gear. The VFs are slugs by comparison, and despite making far more power he may not be any quicker?

Agree with Mark EMS that the VF35 is the pick of the bunch for quick response if you are ditching the TD04, closely followed by TD05/VF24/28/29/30/34, followed by TD06/VF23/VF22/VF hybrids.

[Edited by john banks - 5/17/2003 10:47:10 AM]

Nology

John/EMS,

When you say VF35 is pick of the bunch...care to highlight with some raw numbers or better still if you have the compressor map?

Thanks
keet

john banks

1 bar at 2650 RPM, happily holds 1.2 bar at 6000 RPM. Very little in the way of lag. You won't find a compressor map for it unless you have inside contacts in IHI I suspect.

Nology

Do you know if it will outflow the TD05-16G at the top end?

keet

john banks

It is nothing like a 16G at the top end I'm afraid. I estimate you could get 40BHP more out of a TD05.

MurrayZA

When you say

"1 bar at 2650 RPM, happily holds 1.2 bar at 6000 RPM."

Can you put that into perspective by quoting values on identical set ups, and only the turbo differing (i.e. same boost controller, similar mapping, same zorst etc etc). Maybe the VF35 as quoted above vs the TD04, TD05 16G, VF24, VF23 ?

john banks

This is the most I would run on my own car...

TD04 1 bar at 2300 RPM, 1.25 bar midrange, rolling off to 1 bar at 6000 RPM
TD04 hybrid 1 bar at 2400 RPM, 1.4 bar midrange, 1.1 bar at 6000
TD05 1 bar at 2700 RPM, 1.5 bar at 3000-4000, 1.7 bar 4000-5500 RPM, 1.5 bar at 6000 RPM
TD05/06 20G 1 bar at 2900 RPM, 1.5 bar until 4500, rising to 1.9 bar at 5000 RPM, 1.8 bar at 6000, 1.7 bar at 7000 RPM
VF24/28/29 1 bar at 2700 RPM, 1.3-1.35 bar midrange, 1.2 bar at 6000 RPM
VF23 1 bar at 2900 RPM, 1.4 bar midrange, 1.25 bar at 6000 RPM

[Edited by john banks - 5/20/2003 7:15:27 PM]

MurrayZA

And the legendary VF35 - ever tried / worked with one, jb ? Where would that boost ?

john banks

As I said above 1 bar at 2650, would run up to 1.3 bar midrange, dropping to 1.2 at 6000 RPM.

MurrayZA

Interesting to see the 1.5 bar max on the TD05. These power figures - are you keeping the life of the engine or the life of the turbo in concern?

john banks

The turbo for the figures I outline above, the engine, well As I say these are on my car, I am rather tamer with customer's cars for good reason. My approach with my engine recently (since I decided to build another) is to push it as hard as thermally sensible, although I haven't quite explored the full midrange thrust of the 20G mainly due to the gearbox.

I think the TD05 16G is plenty enough for a standard cast piston engine. Only this and the 20G on this list above I would say go beyond reliable limits for the engine (IMHO over 1.4 bar) - the other turbos are good for lower boost levels but I don't think if done properly will majorly stress the engine.

[Edited by john banks - 5/20/2003 7:30:36 PM]