What would be my options and a place where I could get the parts for me to get a setup for twins. Currently I'm running a 62/71/14 with an automatic, 37" tires, and the turbo lag is horrible. Towing its hard to spool and keep egts cool. I want to go twins for better fuel efficiency aslo. Any advice would be appreciated.

 

I'd say it won't spool any better

Untill you do all the supporting mods

that 71 wheel and an auto lil big IMO (dependant on fuel)
most use a 62/65/14-s475

 

I think the rule of thumb is that a compound turbo setup will spool slightly slower than what the smaller turbo would spool if you ran it as a single

 

It will probably spool a little slower in a compound setup, really not the right turbo for an auto with 37's let alone compounds although some ARE using it in compounds. You'd probably need an S480 or 31 with it . . you need to be calling the twins builders to get it right or you will be just as unhappy after the fact as you are now.

I just put on compounds, choose the 62/65 over an S475 for towing, I have more power and lower EGT's, my spoolup is very fast.



CD

 

Send the turbo back to HTT and have a 65 turbine put on it or use the factory turbo with an S475 compound setup. Auto trucks are very different then manual trucks when it comes to spooling the turbo. Your best beat will be to sell the 62/71/14 and go with the stock/s475 setup.

 

^^^^^^ Yep, get a 65. Way wrong size for single turbo and auto. Would feel like a different engine afterward. I would love to have twins someday too.

 

Also go to a 12 cm housing instead of a 14 if keeping your 62. That is good for about 150rpm sooner spooling.

 

What he said ^^^^ 62/65/12 spools WAY faster, put it over an S475 is some AWESOME fast power. LOVE mine.



CD

 

Thanks for all the advice. Is there anything I can do to get more boost down low out of this turbo. When I am driving any other program than smarty tnt on lvl 7 or 9 will throw the low boost code and the truck goes in limp mode. I lost versatility when I got the turbo since I cant run the lower levels or other smarty programs. What other options do I have with this turbo setup. Also I'm getting my trans redone next month, would a larger stall help.

 

Send it back to HTT (if that is where it came from) and get the exhaust wheel and housing changed. Should be about $400 to get it done. And like was stated get the 65 with the 12cm wastegate. Who is doing your tranny? A stock stall or a little tighter may be the way to go but do the turbo change first and see how you like it. A change to 4.10's may also help but will be expensive.

 

Send it to Engineered Diesel and get there 68mm exhaust wheel, it flows like a 71, but spools like a 65 and its a low drive pressure wheel, unlike the 65mm wheel.

You'll also get much much better customer service, and a better product.

 

Why is everybody avoiding the reason why spoolup is laggy... He needs injectors! 90's if he stays with a single and 120's if he goes 62/S476. Lack of Injectors is what causing lag and heat. Now if he was running 315's or 35's then it would possibly be fine but not 37's

 

i am running a 62/65/12 over s475, it spools great. actually improved my mileage 1-2 mpg if i stay out of it. i am running 80's and a Floor It CP3 kit also

 

Even those with 35" tires and bigger nozzles complain about that particular turbo being a little too laggy in the 2006/2007 trucks. In fact, do a little reading about those years and bigger injectors, those year models are a little picky about bigger injectors.

I have stock injectors, no lag with my current setup of twins. I do have plans to increase my injectors but it will only be 50-75's.


CD

 

It's easier to go from a 65 wheel to 68 than from a 71 to a 68. I asked ED about it and they pretty much said I would be better off and more cost effective if I got a new turbo. I have an sps62 btw. I wouldn't consider this turbo laggy on a stock converter. Whenever i went to a 200 rpm under stock stall the lag was worse but easy to drive around