Why you would NOT upgrade your turbo
- Thread starter Killerbee
- Start date
I noticed a big difference in the top end on my truck - not with his kit but with a stock LBZ inlet and an S&B LBZ intake. I ran .32 faster in the 1/4 on the same exact setup. The EGTs also went way down. I drive like an idiot too much of the time to get any kind of consistant MPG numbers. ChevyDieselLLY's truck gets over 25mpg highway (hand calculated) with just tuning and exhaust. I didn't believe it until both he and his wife told me that they drove over 500 miles then put in 20 gallons; and that they made a 950 mile trip from NC to MI and only stopped once to fill and still had fuel to spare when they got there, and then did the same on the way back. JonathanCasey also reported 23.5mpg hand calculated on a 12 second, 500hp tune on his stock LB7 turbo.
Now back to the interesting discussion of nitrous and tuning.
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I don't have a whole lot of experience in any of this but it seems to me that either way you go (N20 or a bigger turbo) you better have some extra cash laying around because your going to need a built motor one way or the other. I know a few people from my area that tried to spray a ton of N20 and it didn't work out so hot for them. In my head i think a bigger turbo would be better. The power is always on tap, u don't have to worry about running the bottle empty. And larger turbos seem to be as lot more popular than huge nitrous setups so i would have to go the route that more people go and have less issues with. I nitrous was the magical answer everybody would have a few bottles in the box or trunk. I seen a lot more trucks and cars with bigger turbos. Not saying that nitrous won't make the power though, just seems a little more cumbersome.
One thing I haven't seen mentioned (or maybe skipped over) is a big plus when you upgrade the charger.
What is the turbine backpressure vs boost on a stock charger? How about when you throw the coolwhip on it?
If you're seeing 2:1 pressure ratios at 40psi of boost, that's a crap load of force trying to stop the engine from turning. So that 700hp making it to the flywheel could be putting (making up numbers here) 750hp worth of stress on the engine.
This is in effect, coupled with higher efficiency compressor wheels/covers, why people can see huge hp gains at the same boost level.
There is a lot of power hidden on the backside of the turbo.
What is the turbine backpressure vs boost on a stock charger? How about when you throw the coolwhip on it?
If you're seeing 2:1 pressure ratios at 40psi of boost, that's a crap load of force trying to stop the engine from turning. So that 700hp making it to the flywheel could be putting (making up numbers here) 750hp worth of stress on the engine.
This is in effect, coupled with higher efficiency compressor wheels/covers, why people can see huge hp gains at the same boost level.
There is a lot of power hidden on the backside of the turbo.
X 100000000:rofl:
Thats exactly right!
But most of the Group here wont listen anyway so it's most likely a waste of your time, like most of my post's........
But i agree 100%:cool2:
a very good point. Keeping boost "reasonable" on a VVT, keeps passages open. There is no wastegate to compensate for serious backpressure. This goes a long way to support this thread, IMO. Just the concept that upping boost has far reaching consequences not understood by a lot of folks. There is no drive pressure guage in the truck. If there was, we would have a face to the concept.
I thought this was a pretty basic concept, there is no free lunch and as you get well outside the map of a charger the pressure ratio goes to crap and the aircharge gets very hot. Two things you really don't want.
As was stated, it's fairly cheap and easy to stick a pressure sensor just before the turbine.
FREEBIE
Alot of memebers here use a real drive pressure gauge:hello:
I thought the point of this thread was to not upgrade the turbo and use N20
If thats the case how do you deal with the DP from a stock VGT?
super diesel
<<<< Under Pressure
Speed sensor is a need in this field as well if you want to maintain max efficency and power produced by the turbo (even in the VVT). DP is also dictated by this. :hello:
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