The Turbocharger thread

[dannygti]

Blackie, put up your most recent graph so we can see how your CR and turbo choice effect things.

This is meant to be a turbocharger thread with dyno plots, compressor maps and turbine wheel sizes to get people talking about different options.

[blackie_2k5]

my most recent ones are useless tbf mate, i booked the dyno day to be after id been mapped, but id been having loads of trouble with the car..

id been haunted with issues that i only worked out were down to fuel pressure/pump not long after second map, got mapped on 15psi with a restricitve induction set up, and had a massive hold in one of my boost pipes.. so in effect it felt worse on 15psi then it did on 10

removed the filter set up and it felt much better...found the hole night before RR day..fixed that and BOOM..quick as fuck!! but fueling issues were magnified(occasionally not supplying enough and dying off..more often over fueling...amount in tank dependant)

im hoping we can identify the odd shape of the power plot in the most recent one..im thinking its because the turbo is strugling on 15psi, looks like its running out of puff quite soon lol(unknown miles and had play when fitted) it was only supposed to be a temporary turbo but its holding out better then i thought lol!! i was going to get it hybrid rebuilt

so its off the road now to address the issues and fit some new stuff, and hopefully a new turbo, then remap to see if weve cured the problems

most recent:



original..with a much better power plot..but that was actuator pressure of 10psi..so the turbo isnt working hard here:



the compression ratio is around the mid to low 8's(aimed for mid 8s but head is really skimmed so couldnt work out properly), its hitting 15-16psi at just over 3k..but i have a rallye inlet(large plenum to fill), and 2.25" pipework (replacing with 2" asap)

on this set up, it hit 10psi at just over 2k, so even with low CR and big boost pipes(the circuit is quite long aswel..being revised with 2" stuff)

the t25 is pretty good turbo to run at 10-14psi, anything more and id defo look at a diff unit

[dannygti]

Here's some Very useful sites to try and understand compressor maps etc.. Also helps you work out how boost you can run before speeding the air up makes no difference so more pressure results in little gains.

http://www.ztechz.net/id6.html


Another one with dozens of compressor maps on, will more than likely see your turbo on here

http://www.not2fast.com/turbo/maps/all.html


It's saying my turbos peak efficiency is approx 24psi and it would flow around 375bhp if the engine conditions were perfect. Any more boost then gas speed wouldn't result in more power but boost pressure would give me a little more but at the expense of heat.

[blackie_2k5]

second link is quite good, going to see if i can find the map for my turbo later, ive done a fair bit of reading on compressor maps..there is a section devoted to it in that book i sold the other day "forced induction performance tuning"

ive just never really read up on the t25 i have as i never intended to use it for too long at first...and thought ill just run 10psi for a while till i either break it or build a forged lump..

but then realised the non forged route isnt as fragile as certain ppl like to make you think... guessing thats for their own financal gains

id like to see alot more ppl post up their specs/graphs and experiences aswel tbh, im really enjoying this thread, its one of the better discussions that rarely pop up o here, danny you can lead on with the beast

EDIT- acutally theyre both good sites, theres lots of nice reading on the ztech site

[Sophia_Bush]

what do we think to a 2052 i think as discussed on previous page for a gti on a mild setup

[dannygti]

Originally Posted by Sophia_Bush

what do we think to a 2052 i think as discussed on previous page for a gti on a mild setup

I think it would be a great little turbo for a fast road car, would provide an almost n/a like power curve but with the torque to match.

[yr51ocw]

Originally Posted by dannygti

It's saying my turbos peak efficiency is approx 24psi and it would flow around 375bhp if the engine conditions were perfect. Any more boost then gas speed wouldn't result in more power but boost pressure would give me a little more but at the expense of heat.

Danny, be very careful of estimating your pressure ratio. If you look on the y-axis you will see: Pressure Ratio (t/t) P2c/P1c. This means the TOTAL pressure, not the static pressure (static pressure is what is measured by a boost gauge), so you need to add your dynamic pressure (1/2.p.v^2) to your static pressure to calculate the total pressure.

So to work out your dynamic pressure you need to know mass flow rate, area in, area out, temp in, temp out aswell as static pressure in and out. This makes a HUGE difference in the pressure ratio you need to plot on a compressor map.

I have been doing some turbo matching at work recently and fell into this trap. I have seen a reduction in pressure ratio of nearly 1 point by using the correct TOTAL pressure ratio compared to just using static.

If you want further explaining pm me.

[dannygti]

Here is a V V good thread to read if your having issues understanding compressor maps. This thread tells you how work out what power you can make and when the turbo is able to spool up for


http://www.d-series.org/forums/archi...g-dummies.html

Your welcome

[dannygti]

Originally Posted by yr51ocw

Danny, be very careful of estimating your pressure ratio. If you look on the y-axis you will see: Pressure Ratio (t/t) P2c/P1c. This means the TOTAL pressure, not the static pressure (static pressure is what is measured by a boost gauge), so you need to add your dynamic pressure (1/2.p.v^2) to your static pressure to calculate the total pressure.

So to work out your dynamic pressure you need to know mass flow rate, area in, area out, temp in, temp out aswell as static pressure in and out. This makes a HUGE difference in the pressure ratio you need to plot on a compressor map.

I have been doing some turbo matching at work recently and fell into this trap. I have seen a reduction in pressure ratio of nearly 1 point by using the correct TOTAL pressure ratio compared to just using static.

If you want further explaining pm me.

Cumon Marc im not that stupid lol

[dannygti]

Edit, the only thing I'm not able to work out is at what pressure my car will start becoming inefficient. But I will soon see that on the dyno.

Using the compressor maps I have posted is as close as I will be able to get to properly comparing all turbos as neither do I have the money or facilities to properly test what's best.

Your input into this thread is very important to me though so the more you can bring to it and I will be able to learn more.

[yr51ocw]

Originally Posted by dannygti

Cumon Marc im not that stupid lol

Its funny that you claim to know this, but both links you have posted have hugely flawed and have made the common mistake of using:

Pressure Ratio= P2(abs)/P1(abs)

And have not used the correct formula of:

Pressure Ratio = P2(total)/P1(total)

Where total pressure = Static + atmospheric + dynamic

So the links you have posted will misguide people into thinking they are running a higher pressure ratio than they actually are.

If I remember I will scan in a couple of compressor maps I have been working with where I have plotted the raw data and the corrected data and you will see the vast difference it makes.

[dannygti]

That's fair enough Marc but using the formula in my link I worked how much power my car should have at certain boost level and rpm and it perfectly matched the results my car made on the RR...

This gives me confidence the above links are perfectly useable for people like me and other people on this forum. Perhaps not the 'true' way but certainly accurate.

[yr51ocw]

oh for sure, to get you in the right ball park for turbo sizing its perfectly adequate!

But if people are going to get really hung up about efficiency then you need all the info. Efficiency is the name of the game in OEM stuff at the minute which is the reason I have been looking into it.

[Greedo]

Without forged internals, you're playing with fire - and it WILL eventually melt a piston/break a con rod or something.

But out of interest, how reliable would a turbo conversion be if it did have forged internals? More or less 100%? Would it need forged pistons, con rods and con rod bolts OR just pistons & bolts?

[dannygti]

Originally Posted by yr51ocw

oh for sure, to get you in the right ball park for turbo sizing its perfectly adequate!

But if people are going to get really hung up about efficiency then you need all the info. Efficiency is the name of the game in OEM stuff at the minute which is the reason I have been looking into it.

Agree there Marc, if you have anything we can look at from your work I'd greatly appreciate it

Originally Posted by Greedo

Without forged internals, you're playing with fire - and it WILL eventually melt a piston/break a con rod or something.

But out of interest, how reliable would a turbo conversion be if it did have forged internals? More or less 100%? Would it need forged pistons, con rods and con rod bolts OR just pistons & bolts?

eventually is a key word, the fueling you use and the management and mapper is the most important factor in this IMO.
At the end of the day if you are putting 100% more load through the internals their life is going to be substantially shortened.

I've know a few people run over 300hp with forged pistons, standard rods and arp rod bolts. Anymore than this then forged rods are a good idea.

[Greedo]

Originally Posted by dannygti

eventually is a key word, the fueling you use and the management and mapper is the most important factor in this IMO.
At the end of the day if you are putting 100% more load through the internals their life is going to be substantially shortened.

I've know a few people run over 300hp with forged pistons, standard rods and arp rod bolts. Anymore than this then forged rods are a good idea.

Awesome, cheers for the heads up

[jones91]

Hi everyone, im now near completing a turbo conversion on my vts, I will be running a kkk turbo off a seat Leon at about 9-10 psi

Has anyone ever run one of these, how fast did it spool up and what sort of power was it giving out?

[stevo1600]

thats the turbo im running - ive heard lots of good feedback from members on here so it should be quite a good fun turbo.

well i say running. mine hasn't even been started up yet!

fast spool with a good broad power band. perfect for a road car.

[dannygti]

Originally Posted by jones91

Hi everyone, im now near completing a turbo conversion on my vts, I will be running a kkk turbo off a seat Leon at about 9-10 psi

Has anyone ever run one of these, how fast did it spool up and what sort of power was it giving out?

What Leon?
Is it 180hp cupra or a 210/225 hp cupra R?

The k04 on the cupra r is a great choice for a vts imo and I don't think it has done before?

[Matty16v]

I'm a bit of a noob when it comes to turbo conversions. Never done 1 before.

What parts would I be needing to do the conversion?

Turbo
Boost controller
Intercooler
Hoses
Radiator
ECU

What other stuff would I need?