I just put on my Phat shaft 62 yesterday and I have mixed feelings about it. At WOT it's great, hit's 50 psi easily. But on the freeway at 70mph it only runs 3-5 psi and my egt is 800-1000. I'm on the freeway quite often so I don't like that high of temp. My stock turbo would run 15-20 psi and only be at about 700 egt. Is it just that the ps62 takes more to spool up, or do I have a boost leak, or maybe a waste gate problem? On the other hand it sounds so cool through the Scotty II. Any help would be greatly appreciated. Thanks

 

Your boost is about right running that speed, but your egt's seem high, check for boost leaks. Remember, that just because you put on a larger turbo, doesn't mean it will cool as well at a lower rpm. With singles you give up in one area, to gain in another.

 

I notised on larger turbos they have very little boost & high EGT's on the hiway.Just not in there map like a stocker cruising.

 

That's kind of what I figured. I will check for a leak. Thanks for the replies

 

i have a pdr 40 on mine and love it highway running egts around 800-850 and it spools up really quick i know its smaller but iam real impressed with it

 

You can flame me if you want, but at 1000 degrees you're getting a better overall fuel burn than you are at 800 degrees. I agree that it's a little more uneasy, but once you put a real load on the truck (ex: 10k lbs. of trailer) I think you'll see more boost and less heat.

JMHO,
brandon.

 

With my ps64 I'll see 5 lbs @ 70 mph and egts are around 800, so it doesn't sound abnormal to me. I would think the 62 would be running more boost, but am unsure the difference in spool between the 12v and 24v

 

I'm not going to flame you, I agree.

 

So do I.

I bet you see higher mpg as the higher EGT. While the engine is less efficient on paper with the higher egt, the drastic decrease in pumping loss usually offsets that and then some.

I've heard reports of +2mpg with a big turbo like the SPS66, due to the wide open turbine side.

Big turbos usually give better mpg on the hwy, worse mpg in town.

 

i've almost got the truck put back together with the stock injectors and the 62/14 pulling 20k of hey i either had to drive 55-60 in 5th or 75 in 6th to keep the turbo lit and things cool. with the 4's the egt's are at 800-850 cruising. it will make a lot more boost sooner with the 4's but has a bad barking problem. i too have mixed feelings with the phat shaft but doug says they're one tough turbo so i'll see. while putting the head and stuff back on i'm also puting on the new intercooler boots. one of the old boots was almost worn in two from part of the fender so check them closely.

 

your numbers are just like mine sorta hot cruising and then cool off if you light it with out allot of fuel. I am happy with the topend just want a little better spool so im considering sending mine back to become a SPS 62

 

800-1000* won't hurt anything.

as stated above, you'll probably see better empty fuel mileage.