hey thanks for the diagrams bud.

balizticbobo
are the t3s off the ait kit similar to say a highflowed VL t3? as these ait kits made power almost up to redline according to graphs ive seen

cheers

Post up a flow map and we'll see???
The exhaust in most cases would be too small and choke up...
So turbine map would be required...
It will detonate bad if back pressure is more than 2 to 1 of boost...

when you say detonate do you mean blow up like boom ?

Eventually yes!!
Detonation is uncontrolled ignition in combustion chambers. Which can be caused by heat, not good enough exhaust scavenging ...
Ping, detonation will kill any engine...
Suggest you read this...
http://www.turbomustangs.com/turbotech/main.htm

oh ok wow. thanks ill read that after.

my engine used to ping on unleaded fuel ... but now i run premium in it it doesn't ping no more (the guy i bought the engine off told me he used to run premium so i thought id try it and it fixed the pinging problem.)

just for reference, there is a major difference between ping and detonation...

although, both usually make the same kind of sound.

ping is caused by too much ign advance, which causes the flame front to hammer against the piston too early while the pison still traveling upwards

detonation is when there is points of ignition other than that from the spark plug firing and the numerous flame fronts collide and cause the cylinder to ring like a bell

i dont have a turbine map unfortuantely but i have bee told that the rear is a 0.42AR with a 0.48 AR on the comp although im not 100% sure. how do you think this would go on a 250 on LPG? basically i am looking for a street setup and want boost right down low, i would imagine that you would see it at maybe 1500rpm or less? for a daily i would much rather see low down power than top end and one perosn told me that i might get 150rwkw out of this setup. i also plan on using a large intecooler and custom ignition map.

as an alternative i was thinking that seeing as aVL T3 is about the same size, i was wondering what the AR is on a VL T3 highflow usually are? also do the VL T3s have rotating housing as i have to reverse the oil drain to the other side. this may be another alternative?

Cheers

Use two of them. The exhaust pressure will build up bad on one... The A.R is too small..

at what point do you beleive that it would run out of puff and problems would start? 3500rpm maybe?

also i have been reading as much as i can abut turbocharging and i have learnt alot but if you dont mind can you please explain one thing that i cant get a straight explination on. looking at 'trims' and 'AR' ratios is confusing. i have seen turbos that have physically bigger turbines than others but have a smaller AR ratio? i was hoping that you or someone could explain how this and trim specs all work in so i can size them up for myself and not have to nag all you fellas, although i do appreciate the advice.

thanks

See the turbo maps above?? There isn't a t3 there but the flow would be way over to the right as soon as you open the throttle. It's NOT a matter of rpm...A small turbo will become a heater as far as compressor but more important the turbine would cope heaps of exhaust flow....
Unless you have something like a Precision SC61 which has T4 compressor / T3 exhaust housing BUT T350 T04 exhaust wheel...
You have to read maps...
Understanding Compressor Maps

It's all about airflow whether it is expressed in cubic feet per minute (cfm) or pounds per minute (lb/min). In any case it takes about 150 cfm per 100hp....so for 300 horsepower you need a turbo that puts out about 450cfm. The real question is what pressure ratio or boost in psi is this airflow possible with your engine. You need to start thinking airflow and not "boost".


Operating characteristics: The compressor operating behaviour is generally defined by maps showing the relationship between pressure ratio and volume or mass flow rate. The useable section of the map relating to centrifugal compressors is limited by the surge and choke lines and the maximum permissible compressor speed.

Surge line: The map width is limited on the left by the surge line. This is basically "stalling" of the air flow at the compressor inlet. With too small a volume flow and too high a pressure ratio, the flow can no longer adhere to the suction side of the blades, with the result that the discharge process is interrupted. The air flow through the compressor is reversed until a stable pressure ratio with positive volume flow rate is reached, the pressure builds up again and the cycle repeats. This flow instability continues at a fixed frequency and the resultant noise is known as "surging".


Choke line: The maximum centrifugal compressor volume flow rate is normally limited by the cross-section at the compressor inlet. When the flow at the wheel inlet reaches sonic velocity, no further flow rate increase is possible. The choke line can be recognised by the steeply descending speed lines at the right on the compressor map.
I can't seem to edit how I'd like? But the top pics just shows how A.R is measured...
The second is a T3 map....
The next is to show how maps are read... You should be between the surge line [to the left] and choke line to the right.. Hope this helps...

 

 

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thanks for that. very interesting read. i can see what you mean now about the T3. i had also considered something larger, i just had this one with the kit and was hoping to use it. a freind of my has a t04b/t3 on his which is off an F250 and that seems a good unit, power nice and low with reasonable top end. cant seem to find any of these local though. his was imported from a wrecker in the USA. i have a T3 flange on my manifold and need an internal wastegate. the car is a fresh motor with near standard internals, i have a straight gas system which will be set up accodingly for boost pressure and a custom ignition map. any suggestions on a particular turbo. as i said before, im not after a top end screamer just something thats got a lot of low down power and torque with a not too restrictiv top end. thanks for all your help

Just got some new double ball bearing Precisions from Pag parts U.S.A They where sent 0n the 5th and arived to today tuesday 8 th...
Here's the shiping slip....Um there date is mm/dd/yy
Graeme E has requested that you receive a Track & Confirm update, as shown
below.

Track & Confirm e-mail update information provided by the U.S. Postal Service.

Label Number: EC92 1849 738 U S

Service Type: Express Mail - Post Office to Addressee

Shipment Activity Location Date & Time
--------------------------------------------------------------------------------
Delivered Abroad AUSTRALIA 05/08/07 7:23am

At Foreign Delivery AUSTRALIA 05/08/07 1:21am
Unit

Out of Foreign Customs AUSTRALIA 05/07/07 5:00pm

Into Foreign Customs AUSTRALIA 05/07/07 12:45pm

Arrived Abroad AUSTRALIA 05/07/07 12:44pm

International Dispatch KENNEDY AMC 05/05/07 12:22am

Enroute JAMAICA NY 11499 05/05/07 12:20am

Enroute FLUSHING NY 11351 05/04/07 6:03pm

Acceptance HOWARD BEACH NY 11414 05/04/07 4:21pm

Electronic Shipping HOWARD BEACH NY 11414 05/03/07 8:32am
Info Received


Reminder: Track & Confirm by email

Date of email request: 05/03/07


Confirm web site at http://www.usps.com/shipping/trackandconfirm.htm

 

 

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Last edited by EBXR8380 on Wed May 09, 2007 10:12 am, edited 2 times in total.

Are you upgrading again, Graham?

That is a very fast delivery time!

Yea I have two engines in shed a 351 Clevo and 5.0 Windsor.. I'm building a boat engine for ski boat with turbo's...Should have enough grunt...
Good excuse to upgrade mine....

Just a quick question why would you bother with an adaptor for large flange t4 to euro flange t3 when you can pick up a second hand housing for the price of the adaptor and you will have less chance of developing leaks form the 2 gaskets.

Also a t3 of a vl WILL work I had one on my ea as stated a few times throughout this forum it is good for a mild set-up once you start to produce good power it will overspeed the tubo and reliaibillity becomes an issue.

I have another question why does everyone want a ball bearing turbo yes they do spool a little better but to notice the poofteenth that it spools up quicker 99% of people would not be able to tell the difference and when it comes time to rebuild or repair any damage you are better of buying another one as the parts are so damn expensive give a plain bearing t3/4 any day.


cheers Mic