Turbo choice
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Given the choice between what would people recommend? Gt20 or t3. I'm stuck between the two.

http://photobucket.com/quintonrose

GT2056

If something is worth doing, it's worth doing half of.

I'd use the t3...





As a doorstop! GT all the way.

In the 13's at last!.. Just

Neither. Lots of help this thread.

Tell us what you want power wise and you'll get a few ideas. The T3 and GT20 are quite different beasts with different characteristics.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

i think the gt20 would win hands down, maybe a little big for lower boost though

Yes i moved to the darkside

Instagram @jdm_brett

dont be a pussy quinton get a gt 22 :) do it properly

Drives
-Ford S-max Mk2 Ecoboost
-Rover 100 VVC #2 - track project

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or a ball bearing gt25?

Yes i moved to the darkside

Instagram @jdm_brett

No one would be daft enough to stick a gt25 on and expect it to make boost would they?

Lol. Well I aiming high power with a decent spec. Just my original idea was the t3 but after seeing the gt20 now and how well the gt17 has performed a can only want to follow that. But I'm still do work out what comp to go for with the turbo but with the t3 I was thinking 8:1 comp with high 20's psi but dunno now. Stuck with ideas in what I want to do hence the turbo decision first.

http://photobucket.com/quintonrose

gt17 seems to be the one to have it seems to be the jack of all trades comes on boost low and also gives big power

Yea true but if you look at the compression maps for both the 20 and 17 it feels like the 20 can be quite promising aswell or am I wrong?

http://photobucket.com/quintonrose

Do you want more than 230bhp?

If not than the 17 will do the job very well.

In the 13's at last!.. Just

Yea I'm aiming high :)

http://photobucket.com/quintonrose

a gt2052 52 trim will work very well up to 230 bhp wit a bit less flow on the turbine side compared to the gt17, but compensated by a better/stronger spool.

Then if you want to play into the bhp war, a gt2056 will just outbreath anything on a very high boost a serie

the 1752 have a particular design which benefice from a high flow/efficiency compressor (as 2052/2056), matched to a shopped gt20 turbine wich reduce impeeler restriction(trade on boost build), but higher flow.

choose your power class then select your guns

Thanks for that fab. Think I'm sorted for a decision now.

http://photobucket.com/quintonrose

T3

Best 1/4 mile 13.2 seconds @116 mph
First 5 port miniturbo to make over 200 bhp on a carb?
First 5 port miniturbo to make over 200 bhp on Injection?

http://www.mattwoodsphotography.com

What sort of boost is the gt17 having to make (yes i no engine spec needed) to produce the 220/230hp and is that straight out of the box, how strained is theat turbo at that power, is it at its limit so if im on track 5/6 times a year its going to kill it? , do you think( i can sacrifice lag) on a gt2056 it wouldnt be straining as much so would be the better option.

Rick

Sorry if im hijacing it mat help others i hope aswell.

need one or two bag of boost..




Maths:
A-series bsfc is around 0.55 at peak power,
so to produce 230 bhp, you'll need 230x0.55=126.5 lb of fuel/hr
at this power level, around 12/1 afr is needed to produce these numbers: 126.5lbx12=1518lb of air/hr or 25.3lb/min
convert to cfm(25.3x14.27)=360cfm.( optimist side)

Now work on p/r:
assuming 6500 peak power rpm( need high flow turbine):

360cfmx3456(1728x2)/6500rpm=191 boosted ci;
assuming 0.85 ve at peak power (optimist)

191/(0.85x80 cid)= 2.8 p/r ie 26.5 psi of boost at engine intake

then ad intercooler /carb/restrictor pressure drop: +3 psi min=30 psi of boost from compressor:
On compressor map 3 P/R 360cfm/25lbmin

this is the minimum boost/flow needed to sort this power, then these number are the high side, you could calc this with 0.59/0.60 bsfc;13/1 afr;6200/300 max power rpm; 0.8ve;4.5 psi loss thru IC carb and restrictor which'll give around 41.5 psi out of the compressor at 440 cfm:
On compressor map 3.9 P/R @ 440cfm or 30 lbmin

a gt1752 will start to out rev at these flow/Pr I would highly consider a 2056/2259 (rpm wise look at turbine flow), td04h15t, kkk k16/k04 2275

forgotten to put the t3 in the battle, a 0.48 a/r one with 50 trim compressor will just push as much air, with more lag

Fab you lost me at "maths"

bsfc is the volume of fuel needed to produce X amount of power , it is engine specific, and vary with revs, from around 0.45 lb of fuel per hp at max torque to 0.55/0.60 lb of fuel by hp at peak hp rev.
from this you can calculate the volume of air needed at these 2 points.

I took the peak rpm hp a-series bsfc with a conservative 0.55 lb of fuel/hp/hour (generally this is a n/a bsfc mesured, turbocharged it should be higher).

Then if you know your desired hp, just calc the volume of fuel needed to produce it:
0.55x 230hp= 126.5 lb of fuel/hour

Then you find the volume of air needed to be pumped to burn these 126.5 lb of fuel, determined by air fuel ratio (at max power it's needed to be between 12 and 13) so:
12x126.5= 1518 lb of air/hour to burn these 126.5 lb of fuel.

You know know that you need to pump 1518 lb of air/hour, convert this by minutes:
1518/60=25.3 lb of air pumped by minutes.

convert to cubic feet minutes:
25.3x14.27=361 cfm

360 cfm need to be pumped by minutes to burn the minimum quantity of fuel needed to produce 230 hp

Then it is a ratio between your engine volume, his rpm, and his volumetric efficiency, from this you find how much pressure you need to push in his mouth to consume and burn that volume.

For the purists, I didn't applied pressure temp rise in this, so these value are the minimum..meaning it is impossible to produce 230 hp with less pressure and less flow and this assuming 20° temps and 100% compressor/IC efficiency...

After your calcs I got 491 cfm roughly. What else what I need to take into consideration. The gt2056 sounds like the turbo for me even though it sounds like that's on it limits.

http://photobucket.com/quintonrose

As i said go for the gt22

Drives
-Ford S-max Mk2 Ecoboost
-Rover 100 VVC #2 - track project

Searching is all you need on TurboMinis