Turbo upgrade logic

[CMullen]

What are good reasons to upgrade my turbo? are there prereq's like new trans first. i have the juice/attitude power box.

 

[SRadke]

If you plan on using more than 300 RWHP you need to upgrade your turbo.

 

[JVolpe]

Not sure there is ever real logic applied to BOMBing. My goal was to get to 550rwhp at least. I did my tc/trans onced I passed the 400rwhp level. I chose to upgrade my turbo when it became evident that I had enough fuel and boost potential to nuke the stock turbo. My logic was that with enough fueling/boost fooling to push 44psi on the stock turbo I was not really getting enough cool air. I think that the stock turbo will have deminishing returns after 38-40psi if not before. I chose the II SPS66 over twins primarily because of cost and the posted results of users. So far I am very happy with my decision.

 

[Rams-n-Hogs]

JV,



Do you tow with your setup, and if so, how does the turbo act? Also, how driveable is it with the boxes turned down?





Jim

 

[puebla]

JVOLPE: keep us posted and up to date on your thoughts of the SPS-66... alot of us are keeping our eyes peeled for any feedback. Thanks.

 

[JVolpe]

For the last 3 weeks or so I have been running with HOT Juice/Attitude only connected. Juice on level 1(40hp) setting. I have had other things going on and just not a lot of time to play with the truck. I have been making 400 mile Interstate trips on the weekend. My SOTP meter tells me that the SPS66 act pretty much like the stock turbo in this configuration. The spool up is probably slower, but I really dont notice much. Daily driving seems pretty normal and I dont really pay much attention. Yesterday's 400 mile trip at 74mph(1900 rpms) I got 18. 3mpg whick is best yet I think for this truck. The boost level cruising is less than stock at that cruising speed. Stock would be about 6-8psi, SPS66 4-6psi type differences. I just dont see any drivability problems with this turbo on low power settings.



I dont tow anything heavy so I can not comment on how it would handle that situation.

 

[Rams-n-Hogs]

Thanks for the info, JV.



Jim

 

[RMalone]

I second J. V. 's opinion on low fueling spool-up, not really that much different from higher fueling, that is spool up is about the same with tst at 1,1 as 5,3(hp,tq). I do think the sps66 spools slower than stock, its most noticable at 25 to 30mph just cruising. When I stomp the go pedal the wait for power is maddening. I should also mention that switching from the banks 6gun to tst/with the stock turbo also increased lag, so perhaps some pressure would decrease lag, overall I'm happy with the sps66. You can push the stock turbo to 40-45 lbs with lots of fuel (with little benefit), with mild fueling enhancements its hard to keep the sps66 under 40lbs. TST at 3,3 and up gives 40lbs or more, I've seen 55 with tst on 6,6. I run warmer than J. V. though, again pressure might help I really don't know.



Back to your question when to get a larger (or more) turbo/turbos. I think transmission should come before turbo, just my 2pennies. In fact if you have (and want to use) enough fuel to put the transmission or turbo in harms way then both are in no mans land. Enough fuel to ruin one is probably enough fuel to ruin the other. Mods lead to mods to more mods and finally an empty wallet.

 

[CMullen]

Thanks

For the feedback,,,I think I agree with Rmalone, enough to ruin one is enough to ruin the other, so I think Ill keep the box on 3 or below. I want a security system , DC decided to give me a keyfob that is otherwise useles other than locking the doors.



Also the 4 speaker radio sucks with those crappy paper speakers. So i am putting in an Alpine with boston speakers and viper security with remote start





that should get me thru the winter and a few paychecks before i start again :-laf

 

[puebla]

CMullen: The only prerequisite is how full your pocketbook is. If you ain't got the cash... . the stock turbo is the only way to go! For most of us a SPS66 or similar would be nice. For those members going through midlife crisis. Twins are the only way to go.