Stock Turbo upgrades or D66?

daboostcreep · #1 (**permalink**) 05-04-2008, 03:33 PM

There are a few options on the table as I now have over 105k miles on my early 99.

I have the following options:

D66 - $1400 shipped
Rebuild kit with new replacement wicked wheel and non wastgate 1.0 A/R exhaust housing and dp adapter $500 +/-
Possibly a 2.5mm larger exhaust wheel and ported compressor housing inlet - Unknown Price waiting on vendor in Puerto Rico...yuck

So im trying to pair a turbo up with a set of stage 1 160cc single shot injectors.

The D66 while being a great turbo is nearly 3x as expensive as upgrading the stock one, and I doubt stage 1's will even put it in the sweetspot. I figure a fresh rebuild with new wicked wheel, and the upgrade to a non wastegated 1.0 housing will be a pretty good setup. There is also the possibility of getting a larger exhaust wheel from a turbo shop in PR who says they performance rebuild their turbos with a 2.5mm larger exhaust wheel.

Some say the stock turbo is out of efficiency at about 30psi in stock form and that its life expectancy at that pressure is diminished. I understand that, but Im hoping a fresh rebuild and higher flowing exhaust side can help to eliminate some of the restriction and allow better flow/lower backpressure with is a factor in killing turbos.

PS: If the stock turbo performs well with the discussed upgrades and only needs a rebuild every 3 years or so Im totally ok with that. $90 spent over a few years is nothing really.

So if you're EXPERIENCED help guide me to success on a budget.

I have all the supporting mods, 6.0 IC, intake, turboback, dead head fuel fix, boost pump, TW chip, valve body...all the low budget non internal jazz. Oh and a squirt of water/meth here and there.

farmboypowerstroke · #2 (**permalink**) 05-04-2008, 03:40 PM

i'm in search of a turbo too. like ASAP!!! I'm going with either Garrett ball bearing or Turbonetics. I heard that all Garrett turbo's and on some kind of back order and no one will be able to get one before the end of june. If thats the case then i'm going with Turbonetics. Whats the best, and cheapest place to get the turbonetics turbo?

***Dirk*** · #3 (**permalink**) 05-04-2008, 03:46 PM

Quote:

Originally Posted by daboostcreep

There are a few options on the table as I now have over 105k miles on my early 99.

I have the following options:

D66 - $1400 shipped
Rebuild kit with new replacement wicked wheel and non wastgate 1.0 A/R exhaust housing and dp adapter $500 +/-
Possibly a 2.5mm larger exhaust wheel and ported compressor housing inlet - Unknown Price waiting on vendor in Puerto Rico...yuck

So im trying to pair a turbo up with a set of stage 1 160cc single shot injectors.

The D66 while being a great turbo is nearly 3x as expensive as upgrading the stock one, and I doubt stage 1's will even put it in the sweetspot. I figure a fresh rebuild with new wicked wheel, and the upgrade to a non wastegated 1.0 housing will be a pretty good setup. There is also the possibility of getting a larger exhaust wheel from a turbo shop in PR who says they performance rebuild their turbos with a 2.5mm larger exhaust wheel.

Some say the stock turbo is out of efficiency at about 30psi in stock form and that its life expectancy at that pressure is diminished. I understand that, but Im hoping a fresh rebuild and higher flowing exhaust side can help to eliminate some of the restriction and allow better flow/lower backpressure with is a factor in killing turbos.

PS: If the stock turbo performs well with the discussed upgrades and only needs a rebuild every 3 years or so Im totally ok with that. $90 spent over a few years is nothing really.

So if you're EXPERIENCED help guide me to success on a budget.

I have all the supporting mods, 6.0 IC, intake, turboback, dead head fuel fix, boost pump, TW chip, valve body...all the low budget non internal jazz. Oh and a squirt of water/meth here and there.

The d66 is a no brainer. You can use up to stage 2's and will support up to 40psi.

Generally, you are correct about the stock turbo and 30psi. Most of the time, it's around 26-30psi. Anything 30+, and you run a serious risk of killing it.

I can push mine to 40psi or so, and it doesn't sound happy. If you have supporting mods, the stock turbo can push the air.. but it is not recommended.

My vote is for the d66 drop in replacement.

daboostcreep · #4 (**permalink**) 05-04-2008, 03:55 PM

Quote:

Originally Posted by Dirk

The d66 is a no brainer. You can use up to stage 2's and will support up to 40psi.

My vote is for the d66 drop in replacement.

The D66 would be a no brainer if I had $1400 sitting around to burn on just a turbo. Not to mention ideally I'd only do stage 1's. From my experience a turbo is usually at its peak efficiency within a few PSI of its max. For instance 40PSI rated means at about 35 or so its in its prime and as you approach 40 its diminishing return. This is most notable on a dyno and increasing boost 1lb at a time. Most often 1lb will nearly correlate with a certain amount of power increase. For instance my subaru reached a point at 25-26lbs where 28-29lbs only make about 1hp more. And that was after cool down and all...not simultaneous back to back pulls. There is no sense in blowing air that can't be made into power.

***Dirk*** · #5 (**permalink**) 05-04-2008, 04:02 PM

On my last dyno run..

Early 99 stock turbo
25-27psi=380something
35psi=406hp
40-42psi=415hp.

Lots of people have been telling me 420's is about the max on this turbo.

On anyones truck (stock 7.3 turbo), I don't recommend going over 20-25psi. On the d66, you may be able to make more usable boost than you think. But I agree, 35ish psi is probably the sweet spot. Depends a lot on your mods and tunes.

daboostcreep · #6 (**permalink**) 05-06-2008, 12:26 AM

does anyone know if the 1.0 exhaust housing upgrade will fit on an early 99 turbocharger?

**HVAC SuperTech** · #7 (**permalink**) 05-06-2008, 03:38 AM

Yes it does, go to beans diesel and that where I got mine. I wanted to go with the D66, but I was about 400 short at that time, and needed my truck up and going ASAP. Kinda wish I would have waited, but I am gonna do that swap as soon as I get the funds anyhow, and sit mine on the shelf as a backup.