New Turbo Advice

[porkkis]

Originally posted by SteveH
Lag is reduced by two things -

1. WG spring tension (within sensible limits)
2. WGFV modulation by ECU programming

I think there are some bearings in the Turbonetics family which give quicker spool up times as well, but thats an expensive decision you make once.

Paul

3. Ball bearing turbo as you mentioned
4. Short boost lines = chargecooler
5. Impulse EM (???)

[Doug_RS2]

Any thoughts on the one Habib is selling??

Link to For Sale Thread

[MikQuattro]

This is turning out to be a good thread... I don't really have anything to add, more of a question really. I've read in a few places that intercooler size will affect turbo lag, because the more space there is for the air to build pressure, obviously the longer it will take to do so. Going by that, if you slapped a mammoth IC onto a stock S2, your turbo may perform more efficiently due to the cooler air, but theoretically it would increase lag. Adding a bigger turbo would help the situation since you'd actually be pushing more air, but then I guess you lose efficiency.

I've been reading up on this stuff because I would like to get the most out of my engine without dumping a lot of money into it. I guess I'm learning to tweak my current setup... Anyway, anyone have any opinions on this stuff? Can anyone confirm what I'm babbling about?

[Mark Halligan]

Hi Doug,

Its true, unfortunately the aeroquip type hose ends and hoses are expensive , but IMHO they are worth well worth it, if you have to make custom lines up, you have to make them as reliable as you can if you are spending your hard earned on a new turbo. Additionally these hose ends are re-useable so if you change the turbo or manifold later on as the need for power drives you further down the modification route, it is easy to re-make any of the lines if you need to.

Lag: well, so far I am a fan of Ceramic ball bearings, they are definately assisting my 63mm turbine spool up a lot quicker than the normal floating bearings would.

If you ever need any help with regard to choosing hoses and ends let me know, in the meantime get a catalogue from these people:

http://www.netcomuk.co.uk/~lfracing/home.htm

they will also make the hoses up for you if you want them to, to your specifications.


Cheers

Mark.

[Doug_RS2]

Cheers for the link Mark.

What did you do about the connections that have a plate with 2 bolts holding the hose in place? *******ise the original end or tap the hole?

[Mihnea]

Doug,

First off, I don't think a rolling road session is really worth it but first off I need to know what can still be done and where on your car. The reason I'm saying the RR isn't necessary is because I can't remap a car properly on an RR, if I could have remapped Mark's on the road, we'd have gotten at least 20 more HP and at least 500 Nm instead of the 470 he has (and which are already good, agreed on that one). My point is that you have no "feelings" of what's going on and at which RPM specifically on an RR and additionally it's extremely noisy, hence my preference for road tuning, also just because everyday you drive on the road, not on the RR.

Okay, next step, if you don't think you'll be shooting for 450+ HP, just get a racing K26/27/29 from me with racing 360 degree thrust bearing, it should be the same price as the Garrett one, except you don't have to trade your RS2 turbo in (well I could ask for it but I won't, there's lots of people looking for one and you can resell it for about 7-800 Euros fully rebuilt) and it works just fine on the RS2 EM. That turbo's cold side is good for about 560 HP with a bigger hot side (SQ EM necessary) but with the #8 K26 hot side it will work great for about 420-440 HP and loads of torque. It should be a bit laggier than Mark's hybrid, mainly due to the absence of ball bearings, but with a good stiff WG spring from me, it should work perfectly fine.

Cheers,

Mihnea

[Doug_RS2]

Ok Mihnea, Can you pm me details of the turbos you can do for me and some prices?

Are these still requiring custom oil/water lines? Custom Intake/turbo hoses?

Cheers for the help
Doug

[S2central.net]

Maybe that's a plan - its far enough ahead... I could book some roller time for Friday afternoon.

We could do some chipping and on-road mapping on the Friday morning for those that need it.

Mapping on the rollers sucks more than Mr.Twig.

Let me have a chat with Mihnea and see what we can arrange...


Paul

[Dr H]

Mihnea

For some strange reason I have just received a PM that was meant for Doug do you want me to forward it to him or will you resend it. Or maybe you got it as well Doug?

Leigh

[Mihnea]

Oh Leigh, sorry for that m8, it was meant for Doug indeed, I'll send it to him again, dunno why I've clicked on your name rather than on his

I'll stop having so I don't go totally :wacked: before sleeping everynight

[Mark Halligan]

Doug,
yes you can *******ize the original plate mount by welding a JIC weld nipple to it. Heres a pic sorry for the blurry image.

If you use a garret type turbo, the hole is usually threaded as well, therefore giving another fitting option.

Mark.

[Doug_RS2]

Cheers Mark - Are these standard plates - Can they be bought anywhere with a threaded adapter already fitted?

[audiman]

Just got on the bandwagon, bit late sorry guys. Yeah my 26/27 with the #6 housing is only capable of about 380bhp (i think). Im using RS2 EM, but the conrods wont take that nor will the crappy ignition system.

But on the lag side of things if you are not in the mood for stupid caning sessions then it does get on your ****. The car is flat before 2.5-3k. But then it hits hard. I think the only real way of getting a turbo to boost low down, like standard car, is to go with a smaller turbo such as the rs2 one. With good mapping this should be spooling quite early in the rev range.

But then its a toss up on the amount of power you wish to have. If you are happy with 300 ish bhp then fine stick with the low lag option. If like me you want a bit more and dont mind the lag then get something like my turbo or an even larger one.

I have driven a friends 911 turbo with a huge k27/29 blower and that doesn't even spool until about 4000rpm!! But you dont have move when it does.

[audiman]

Sorry for the essay.

[Doug_RS2]

Like I said before I am used to 3500rpm kick and that makes it an easy car to drive sensibly or keep your license - It also means I can cruise at 80mph on the motorway and not have the turbo spinning - That's how I got 380 miles out of one tank and got from Dunfermline to Billing without refuelling (well, nearly - I refuelled when I got lost, 2 miles away)

Tom - Does your Turbo have a bigger compressor inlet? How did you get round all the plumbing for that hose?

Did you have to change oil/water lines? Any pics/how tos?