1-5-3-6-2-4

Ok turbo experience guys.


this hx55 I want to plonk on my engine. measures out 68/74/13. no wastegate.


so my config, 12v. lots of fuel. nv4500 and a heavy truck.

what say you? drivability? spoolup as single? 74mm turbine... hurts or helps? explain this surging deal to me. I've never had that problem before. probably want to avoid it though I guess. or so I hear. I'm not really conserned about towing. I rarely every tow anything. and my trailer is for sale. so i won't be towing that anymore. Its a play truck, but i still dont' want it to be a douche to drive on the street.

Tate

RPM will be your friend with that turbo. My silver bullet is a 66/71/0.8 A/R and it doesn't come alive till 2k. Your housing is probably more comparable to a .75 A/R, but you are still spinning more mass. It would be driveable, but get some valve springs on that truck so you can run it to 4k.

Mike Holmen

I'm with Tate, its gonna need some big rpms to lite that turbo up. A tighter turbine housing like the one that Tate suggested, and go with a smaller turbine wheel. It will help to lite the turbo up. You'll probably bark the turbo during shifting, on a decent hard wot blast. Once the turbo lites up, hold on.

RowJ

I tried a HX-55... 66/72/14! Granted that was on an Auto, but it was a disaster!! Lived with it for about two months before it drove me to twins.
Older technology and heavier metal in a Holsett, combined with the big size is, IMO, a formula for misery.
Take each gear to 3000 rpm and it might be street livable...just barely.
This time of yr, in your part of the world...maybe doable. But watch out when summer comes!!
JMO

RJ

dodgediesel

Luk, give Greg a call @ Truck Specialties 1-574-202-3465. He has a HX55 based turbo that spools crazy fast. A little more dough but I guess they are super impressive. I talked to him last week about turbo's but I'm thinking twins are the way to go nowdays...

1-5-3-6-2-4

Its not an old technology HX55 that I'm oogling. Its the Holset off the Detroit DD15. The engine was just introduced this year, its Detroits answer to the future. and its a design all its own, well with styling cues from the Mercedies family. that Holset is new technolody there is no doubt about that, with the amount of R&D that went into introducing the DD15 as the new face of Detroit Diesel.


so anyways the point in I can get on cheap like borcht on my employee price. no aftermarket guy could touch I can guarrontee.

dvst8r

There is only one way to find out how it will run.

Mike Holmen

Luke, just food for thought, does anybody have a VGT turbo around that 66-70mm inducer size for a highway truck? I read on competion diesel forum that guys are using the vgt off a ISX engine (S471 size I think). I think that it would have abit better street manors than the HX-55, of course you'll have to rig up a way to get the vgt part to work mechanically, but thats not a big deal. I bet that you'll get a bigger turbo with better spool-up. That HX-55 would be a sweet deal, if it had vgt on it.

1-5-3-6-2-4

Im in opposite mind set. I don't want anything VGT or VNT on my turbo at all.

the theory of design on all those devices is to choke the turbine housing to drive exhaust gas to the EGR system.

and I change so much of that junk in my day to day work that I really have no intention of ever having such a thing on my truck my choice.

heres a Holest 561 or 563 IIRC off an EPA'07 Series 60 Detroit. the compressor inducer isn't that big but the compressor housing is very large. I dont want one for my pickup.

dvst8r

I think the HX-55 and some fuel will be just fine, I ran a 97 12v manual with a gt4294 with a 1.01 T4 hotside for several months, it wasn't great, but it wasn't underivable, and let me tell you when it lit, it sure put a smile on my face.

Mike Holmen

Luke, what size is the exducer on the compressor impeller? The egr valve causes the turbo to gunk up with carbon/soot, so the your just seeing the end resultant. The variable housing size, just varies the area sizing so you have a variable smaller and larger turbine housing area. I can't explain the large compressor housing, and small impeller size, other than allow the compressor flow more. I always wondered how good that the new hiway emission stuff works.

I've been reading that the VGT electronic stuff seems to fail regularly thats why its cheap cheap...I want to put on mechanical stuff to adjust the vanes. The variable vanes just extends the size of the turbine wheel. It similar stuff just different manufacturers designs. There are a few threads on comp diesel.