JThomas

Well i purchased a Htb2 62/12 compared to my old hx40/16 your turbo seems to be running 200-300 degrees hotter under normal driveing. This turbo uses more psi under the the same conditions with the higher egt's. Pulling the same hill 75mph with lawn trailer in tow Htb2 30psi 1100-1200egt With the hx40/16 i was running about 15psi-20psi max I would see 800-900 egt. Over all this turbo has great low rpm responce it just seems that once it reaches 2000 rpm things start to heat up as to where the hx40 cooled more. On the interstate when i go to pass some one things heat up alot faster. With the Hx40 70mph 600-800egt Now Htb2 800-900egt all the time dosen't go below that unless you coast I need help did i purchase to small of a turbo or wrong size exhaust turbine

wap

I would contact HTT directly and see what they say, but from talkin to people and based on what I have read you may want to think about upgrading to the 14cm housing. The 12 should cool better in mid range and the 14 should do better in the upper rpms.

Hope this helps but I am sure on of the turbo gurus will chime in.

RJF

Well of course your EGT's are up, you went from a big 16cm exhaust housing down to the same size found on a stock HX35, a 12cm housing. Your EGT's don't sound that bad yet anyway, you can pull a hill continuously at 1250*.

Roger rodbolt

JThomas,
I suspect your change in egt is due to a boost leak or drive pressure leak (exhaust) so you really need to pressure test your cold side from the turbo inlet to through to the engine. Make an adapter and pressurize the sytem while spraying soapy water on all connector. I saw a customer truck that had a cut oring on the cold side turbo connection, another just left out the oring!! Look for soot or exhaust leaks around the turbo/exhaust manifold with a flashlight and mirror.

The cm size of a Holset and 300 based HTT turbo are not the same. A 12cm HTT Schwitzer housing flows more or is less restrictive then a Holset 12cm. Depending or which 14 HTT housing may be comparable or larger the your old HX40 16cm. Also it is normal for egt to be hotter in cruise or light tow with a larger turbo! You may be only using <150hp maintaining your speed with a trailer on flat ground, there just isn't enough drive pressure to spool a larger turbo so you run less boost then the stock smaller turbo, hence less air and higher egt. With equal (or even a bit less) boost the larger turbo will result in less egt but it needs a fire lit to keep it working. Any leaks in drive pressure or boost will show up in cruise egt and poor economy, yet the truck may run fine and keep wastegated boost at full throttle.

My experience is the the 62/12 is a better towing turbo then the 62/14 and is a bit better then the HX40 for towing, definately better all round turbo then the HX40. Please check it out and let us know.