TURBO UPGRADE

TurboGTU · January 15, 2003, 01:08:53 AM

OK, since I've heard that the stock .80 on the M24 can't flow verry well and max is about 15 and its spinning its tail off at that point. Then how about putting the turbine and compresor fins from a bigger turbo or an aftermarket one then modding our stock compresor and turbine housing to accept them by making the turbine and compresor holes bigger and porting the housing to flow better. Seems like this is what people and turbo companies do. I will need a turbo rebuild kit soon since my turbo smokes like a bar-b-cue when idling at a stop for a while. No its not the oil return line(checked and its clear and stright down). Maybe make a list of turbines that could fit into out compresor and turbine housing to make a kit for these turbos for cheap. Heck or make it your self to save hundreds.

If anyone has their TGP turbo apart could you tell me your turbines shafts diameter and lenth from the intake part to the exhoust part without the nuts on though. I think this is all I need to search for one. I have mine but its already going into the car. Till I find a good substitude the turbo will stay on.

twinturbosedan · January 15, 2003, 01:34:46 AM

have you thought about just getting a different (T3) flange put on the crossover and using a T3 turbo from a 2.3 Thunderbird Turbo Coupe or another car? T3's seem so much more common than the T25.

btw, what does 'M24' mean? i know it is cast into the turbo, but someone was telling me that it was actually the nickel content of the housing?
joshua

Chris A · January 15, 2003, 05:27:03 AM

slightly off topic, but the oil return hose can LOOK ok, but really be bad. If you take it off and look through it it may be ok, but if it bends a little or gets hot, the inside that is blistered will expand and block the oil return.

As far as bigger wheels, you can get about 20% more flow out of this turbo for a cost of $800. Not worth it if you ask me. You can either change the flange setups, or goto the t3/t2 hybrids that WORK well on other apps (haven't seen it done on the TGP yet) but as I posted somwhere else, can have drawbacks. None the less its a good upgrade to keep the stock flanges.

TurboGTU · January 15, 2003, 07:01:14 PM

I thought the T3s from the eclipes/conquest/daytonas/saabs/turbocoupes/Murkers/SVO Mustangs were smaller than the TGPs. I know because I helped my older brother rebuild his engine and it had a .60 A/R(I think) size turbo on the Turbo coupe and there are others that are smaller on the Turbo coupe. We used a Murker turbo. The TGP has .80 A/R, or does A/R (area radius) don't tell how big and how much a turbo can flow? I know of a Ford pinto that used a 2.3 (140ci)turbo motor from a SVO mustang but had an upgrated T3/T4 hybrid that had a A/R of .83. and it flowed 3hp per cu. in..420hp.

What would the turbo on the TGP be called? I.E. a T2, T3, T4.

twinturbosedan · January 15, 2003, 08:14:23 PM

i'm just learning turbos myself, but i think comparing A/R ratios between different classes of turbos (T-25/T3/T4) is comparing apples & oranges. the TGP turbo is a Garrett T-25 - aka T-too small.
joshua

eclipse5302 · January 15, 2003, 08:42:33 PM

I think malibuolds is right, comparing a/r ratios between turbo types (T3/T25) is like comparing apples to oranges.

Example...

The T3 I have for my Cutlass:
Compressor A/R is .63
Turbine A/R is .60

The stock TGP T25 is:
Compressor A/R is .80
Turbine A/R is .60

The T3 has much larger turbine and compressor wheels, even though the numbers are smaller or identical. I remember reading somewhere that the A/R has to do with the restriction of airflow on the turbo. Not sure if thats true though. I'll have to do some research.

Jason

TurboGTU · January 23, 2003, 12:08:33 AM

I got my older bros old used turbo. Its the one off a Murker 2.3l-needs rebuild (now he has a SVO turbo). I put the TGP turbo next to it to compare and the dam TGP is dam small. The Murker t3 turbo has the .60 compresor and .63 turbine. I can have it rebuild as a t3/t4. I can reangle the compresor,turbine housings and the center section like the TGPs', but the exhaust down pipe flinge will face up ward unless I fabricate one, and the whole crossover will need to be replace by a custom one. I don't know if its realy worth the try. I just want to put it on like it is without a down pipe (this means no hood-since the flinge will face upward) and a half ass X-over that I can make to test it.
I think A/R is just the percentage of its size that is used. The TGP .80 A/R might be the same actual size as the T3s .60 A/R. A T3s .80 a/r might = a TGPs 100 A/R. Well at least that is what I understood.

Chris A · January 23, 2003, 05:35:08 AM

Turbo sizing is kinda complicated to explain, but its not a percentage. Its a ratio of the relationship of the cross sectional area of the scroll to the radius of from the center of the wheel to the center of the scroll. It plays an important part in how a turbo will respond. You can have two turbo's both with the same wheels but respond completely differently on a motor because of the A/R.

eclipse5302 · January 23, 2003, 10:48:36 AM

I've also heard that the A/R has to do with the restriction of the housings. Like the TGP turbo is an .80 compressor and the Merkur (Ford T3) compressor is a .60. So that one flows better...I think thats how it works. But there is a lot more to it, like Chris said. But to make matters simple, you can't compare the A/R numbers between any two different turbos (T-25 and T-3).

And the Merkur T3 you've got is the same one I'm putting on my 3100 / 3.1 Turbo project in my Cutlass. It also came in a Ford Turbo Coupe, 85/86, among other rides. I'm just waiting for the rebuild kit, I'm only rebuilding it to stock for now. I'll probably run a external wastegate because of the weird DP situation. I can get a flange and weld the piping for the DP/external wastegate easily. But it will all have to be custom...no bold ons here. The larger turbo works with 29lb Sy/Ty injectors and the 3100 heads/roller valvetrain and custom chip. Should go pretty good with the 5 speed.

Jason

skalor · January 23, 2003, 03:11:17 PM

first in computing the best turbo for an engine you must know a couple of things.

engine size- 192 CID
engine type- 4 stroke
maximun speed- 5200 rpm
maximun boost pressure - well just say 14 psi
ambient temp- 70*F is a fair #
barometer- 29 in Hg. is also a fair #

1.)start by converting displacement to cubic feet:
192 cu in.
------------------ = .111 cu ft.
1728 cu in./cu ft.

2.)next calculate the ideal volume flow through the engine:
.111 cu ft. 5200 rpm
------------ X ------------ = 288.6 cfm
revolution 2

3.)but that's at a volumetric efficiency of 100%, so reduce the VE to 80% for at least a closer guess:
288.9 X .8 = 230.88

4.)assuming a 65% compressor efficiency, calculate the density of the intake-manifold air(multipling by 2.03 converts psi to in. Hg.
manifold pressure abs
pressure ratio = ---------------------------
inlet pressure abs

14 psi + barometer
= ------------------------
barometer

(14 x 2.03) + 29.0
= ----------------------
29.0

= 1.98

5.)use a table to find Y for normal air and diatomic gases, which turns out to be .21

6.)ideal temp rise-AT(ideal): where A means delta, also note that 460*F is added to convert to degrees Rankine)
AT(ideal) = Y x T
because inlet temp is 70*F
AT(ideal) = .21 x (70*F + 460*F)

= 111.3*F

7.)Actual temp rise-AT(actual):
AT(ideal)
AT(actual) = --------------------------
compressor efficiency

111.3
= --------
.65

= 171*F

8.)then calculate the intake manifold temp
= compressor-inlet temp + AT(actual)
= 70*F + 171*F
= 241*F
air will not actually be this hot due to the cooling effect of fuel, plus it doesn't take into effect intercoolers

9.)Then calculate density ratio-DR:
inlet temp outlet pressure
DR = ------------- X ------------------
oulet temp inlet pressure

70 + 460 28.4 + 29.0
= ------------- X ----------------
241 + 460 29.0

520 57.4
= ----- X ------
701 29.0

= 1.47

10.)Under these conditions the:
compressor-inlet flow is = compressor-outlet flow X density ratio

= 230.88 cfm X 1.47

= 339.4 cfm

11.)now convert cfm to lb/min
lb/min = cfm x .070318

= 339.4 x .070318

= 23.87 lb/min

Now all you have to do is go back to step #2 and replace the rpm with a couple of different numbers. After you map 2 or 3 different rpms, take those figures and compare them to turbo compressor maps. Make sure that that all of the figures you mapped are in a good efficiency range on the compressor map you choose. Please, take into account these are some very rough calculations on my part. I'm sure glad that those Chem 1/2 classes came in handy somewhere :D

Sorry that it's hard to follow, but the BB didn't like my spacing. If anyone wants I can convert it to HTML and post the site.

Also, here's a link to some compressor maps to help track down a good match.
http://www.turboneticsinc.com/comp_maps/fig5.html

TurboGTU · January 23, 2003, 07:16:18 PM

Josh got skills. Dam wish I knowen that. I'll check up on that though. Thanks man.

and here's the side by side I took .. yes the resolution sux.

http://image1ex.villagephotos.com/pubimage.asp?id_=1428100" width=256 height=256>

SHE's so tinny. :o
The down pipe will face upward without any costom work on the t3.
But now I will see if I will need it for the future.

Chris A · January 24, 2003, 12:37:05 AM

HA finally a comparo picture of a T25 and T3! I knew the T3 flange was bigger!

There are wastegates available that can replace the elbow on the tbird turbo, then you can have a downpipe straight off the back, i think the are usually vband style fittings so a downpipe would be pretty easy.

skalor · January 24, 2003, 10:36:04 AM

My friend is into 2.3Ts...he has a '88 Turbocoupe(stick) so it has the IHI and not the T-3, but the exhaust manifold flange is the same. He also has a '90 Ranger that he put a 2.3T into it and that thing is such a sleeper. Anyways, he always makes fun of my T-25, and from those pictures you can see why :( .

Hey Chris A, do you have the compressor map for our T-2small? or do you know anyone that does have it? I've looked all over the internet, but there are only a handful of T-25 compressor maps out there.

TurboGTU · January 31, 2003, 02:31:27 AM

http://www.relentlessracing.com/images/closeup_swingvalve.jpg

was this the wastegate that you were talking about? $120 is the asking price on this site. relentlessracing(.)com. They have all sorts of stuff I need for the turbo should I do a swap with the rebuild kit for the t3.

ReallyFastZ24 · January 31, 2003, 02:15:58 PM

Hey there, just signed up -- i'm swapping this motor into my cavalier, yet i was going to have a custom crossover pipe made because of the motor mount problem. I was wondering if anyone has a picture of the motor mount out of the beretta in the above pictures. I'm going hunting tomorrow -- this is EXACTLY what i needed to see the pictures of, and i have a feeling my car project will be done veryyyyyyyyy soon, and for a whole lot less money than i had anticipated.

-- Lee