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Engine Specific Info and Questions => IDI Engine => Topic started by: davidskipper123 on April 05, 2011, 10:35:09 am

Title: HX25 on a aaz ?
Post by: davidskipper123 on April 05, 2011, 10:35:09 am

will a hx25 have laughable lag with moderate pump upgrades and the such?

Title: Re: HX25 on a aaz ?
Post by: RabbitJockey on April 05, 2011, 03:40:00 pm

i think it will be ok but i am not certain, the hx27 has been used before with good success

Title: Re: HX25 on a aaz ?
Post by: colhel59 on April 05, 2011, 09:24:24 pm

I would also like to know i have one off of a case skid steer freebiie

Title: Re: HX25 on a aaz ?
Post by: blackdogvan on April 06, 2011, 07:41:32 am

Post the map!

Title: Re: HX25 on a aaz ?
Post by: R.O.R-2.0 on April 06, 2011, 07:48:05 am

Quote from: blackdogvan on April 06, 2011, 07:41:32 am

Post the map!

thats the best thing to do..

Title: Re: HX25 on a aaz ?
Post by: davidskipper123 on April 06, 2011, 01:13:47 pm

dunno where i could get the map from ?? all i can find is catalogues :(

Title: Re: HX25 on a aaz ?
Post by: davidskipper123 on April 06, 2011, 01:24:50 pm

(http://i1214.photobucket.com/albums/cc485/Dave_JaVu/HX25compmap3.jpg)

hope that gives someone an idea ?

is there any guide on reading compressor maps ? would like too learn and i think if someone posted a lil thread a about them quite a few people would benefit!!!

Title: Re: HX25 on a aaz ?
Post by: RadoTD on April 06, 2011, 02:32:35 pm

That turbo looks decent for an AAZ to me. A bit on the big side maybe, but it's good on it's own for 25psi easy, even 30 shouldn't be much trouble. It likely won't spool super quick though... it appears bigger than a K24

When I get home, I can find a guide to reading compressor maps, I'm at work right now though. If you google, a few things should come up. IIRC, Garrett's website has good info

Title: Re: HX25 on a aaz ?
Post by: RabbitJockey on April 06, 2011, 02:40:12 pm

looks ok from what i can tell, but i am not that great with compressor maps

Title: Re: HX25 on a aaz ?
Post by: RabbitJockey on April 06, 2011, 03:25:52 pm

i think 30psi would be too much maybe 25 at the very most and even that i think would be over spinning it

Title: Re: HX25 on a aaz ?
Post by: keaton on April 06, 2011, 05:33:19 pm

add a smaller turbo to help spool the bigger one  ;D

Title: Re: HX25 on a aaz ?
Post by: RabbitJockey on April 06, 2011, 06:12:02 pm

honestly i don't think this will be too big at all, it will be a good turbo for 20-25 psi

Title: Re: HX25 on a aaz ?
Post by: RabbitJockey on April 06, 2011, 06:43:58 pm

u no i get too confused when reading the maps there are so many variables, just disregard everything i posted haha

Title: Re: HX25 on a aaz ?
Post by: Alcaid on April 07, 2011, 05:10:02 am

The compressor side of this turbo looks like a good candidate for a AAZ if head is optimized.

Calculations and plotting I just did:

(http://i14.photobucket.com/albums/a345/Alcaid/GTD/HX25AAZ.jpg)

The four points on the graph:

Green = 1bar/15psi boost @ 2000rpm
Yellow = 1.7bar/25psi boost @ 2700rpm
Orange = 2.0bar/29psi boost peak @ 3000rpm
Red = 1.7bar/25psi boost @ 4500rpm


If you run the turbo with max boost 1.7bar/25psi it would produce somwhere in the region of 175hp/230ft-lbs (crank numbers)
If you let the turbo peak up to 2.0bar/29psi in the middle range you would gain some torque, somewhere around 175hp/255ft-lbs


If the turbine side of the turbo is matched to the 1.9 litre displacement to support this boost curve is a different question…

Title: Re: HX25 on a aaz ?
Post by: davidskipper123 on April 07, 2011, 05:48:56 am

that sounds promising :)

Title: Re: HX25 on a aaz ?
Post by: davidskipper123 on April 07, 2011, 05:50:51 am

and by optomising im assuming you mean a port and polish ?

Title: Re: HX25 on a aaz ?
Post by: Alcaid on April 07, 2011, 05:52:33 am

Yes, bigger valves wouldn't hurt either :)

Title: Re: HX25 on a aaz ?
Post by: davidskipper123 on April 07, 2011, 06:04:57 am

thats gonna be alot more than my budget can allow me thinks how much bigger we talking what are standard sizes ?

Title: Re: HX25 on a aaz ?
Post by: Alcaid on April 07, 2011, 06:15:45 am

The earlier AAZ heads has 8mm valve stems:
Intake: 36.0mm x 8mm x 95.6mm
Exhaust: 31.2mm x 8mm x 95.6mm

Later on they moved over to the 7mm stem size:
Intake: 36.0mm x 7mm x 95.6mm
Exhaust: 31.0mm x 7mm x 95.6mm

Something like 37mm intake and 33mm exhaust would be nice: http://performance-diesel.com/index.php?main_page=product_info&cPath=2_1&products_id=3 (made for VE TDI, so slightly longer (1.3mm) but would be perfect for a IDI application with a reground camshaft)