LT1: N20 vs Turbo discussion
11-22-2010, 05:46 PM
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LT1: N20 vs Turbo discussion after some reading, i am seeing a lot of evidence that guys running LT1s in stock bottom form prefer Nitrous.
I'm not exactly saying it's normal, but there are some that have sprayed stock bottom LT1s with 200-250 shots with incredible results and surprising longevity.
I'm just throwing this out there for discussion... why do you guys think the same can't be done with boost?
my first thoughts were cylinder pressure in the event(more often than not ie STS) that a quicker spooling turbo is used and full boost is reached before or around peak torque... do you think that this, in conjuction with the higher compression ratio, is just too much for the oe pistons?
my thoughts are.. what about a larger, later spooling turbo that didn't really come on until At or just after peak torque? therefore minimizing the huge spike in cylinder pressure. i do realize the potential loss in tq but feel it could be made up as hp later on without beating the oe pistons so badly(yes, maybe more of a trap car than an ET car)
i know the general thoughts around here are Boost=$$$$$ and how insane i sound just by using terms like boost, budget and longevity in the same breath lol, i'm just opening this for discussion... are we doing something wrong or is it just the design? why N20 but not boost?
I'm not exactly saying it's normal, but there are some that have sprayed stock bottom LT1s with 200-250 shots with incredible results and surprising longevity.
I'm just throwing this out there for discussion... why do you guys think the same can't be done with boost?
my first thoughts were cylinder pressure in the event(more often than not ie STS) that a quicker spooling turbo is used and full boost is reached before or around peak torque... do you think that this, in conjuction with the higher compression ratio, is just too much for the oe pistons?
my thoughts are.. what about a larger, later spooling turbo that didn't really come on until At or just after peak torque? therefore minimizing the huge spike in cylinder pressure. i do realize the potential loss in tq but feel it could be made up as hp later on without beating the oe pistons so badly(yes, maybe more of a trap car than an ET car)
i know the general thoughts around here are Boost=$$$$$ and how insane i sound just by using terms like boost, budget and longevity in the same breath lol, i'm just opening this for discussion... are we doing something wrong or is it just the design? why N20 but not boost?
11-22-2010, 05:56 PM
#2
One word = hypereutectic
They put more silicon in the aluminum and that makes the metal (LT1 piston) a little more brittle.
They put more silicon in the aluminum and that makes the metal (LT1 piston) a little more brittle.
Last edited by 96silverram; 11-26-2010 at 03:03 PM.
11-23-2010, 03:40 PM
#3
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your question could be answered by how many posts there are starting with:
"I got xxx amt of dollars and i want to make as much power or run as close to xx.xx time as possible while spending the least amount of my money."
AND
"I am thinking about a turbo build."
some people are just not as committed as others to follow through with a successful turbo build. boost also does not have as much of a support group here so choosing the path of least resistance (aka nitrous) seems quite logical. i was almost crucified on a supra forum for telling a guy the quickest way to 300rwhp in his N/A supra was to keep the automatic and spray it or SBC swap it instead of convert to a 5spd and build a donkey dick NA-T setup.
"I got xxx amt of dollars and i want to make as much power or run as close to xx.xx time as possible while spending the least amount of my money."
AND
"I am thinking about a turbo build."
some people are just not as committed as others to follow through with a successful turbo build. boost also does not have as much of a support group here so choosing the path of least resistance (aka nitrous) seems quite logical. i was almost crucified on a supra forum for telling a guy the quickest way to 300rwhp in his N/A supra was to keep the automatic and spray it or SBC swap it instead of convert to a 5spd and build a donkey dick NA-T setup.
11-23-2010, 03:53 PM
#4
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Here, read this that I posted on another site, and she what you think after this. LOL... I am so far deep in now though that I am going to roll with it.
http://ltxtech.com/forums/showthread...STS-turbo-help
http://ltxtech.com/forums/showthread...STS-turbo-help
11-23-2010, 11:02 PM
#5
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I dont know much about metals or technical things about engines. But Ive been around for a while and always wanted a boosted car, the pistons cant handle it.. No stock shortblock ever lasts on 9-10psi, its a ring land or a hole in the piston,thrown rod. Unless the tune has some much timing pulled out and rich as hell....
They dont handle boost like they can take n2o. A good tuned 225 shot DP kit will last a little while in a good setup LT car. No 9psi LT1 car with a semi aggressive tune would live long, especially if you turn any hi rpm. Pistons mainly are the issue.
My point is vtec(guy on there with a LT1 3rd gen) run's 9.40's @144, and plenty others behind him running 10 or low 11's on stock shortblocks. How many FI stock shortblock LT1's have you heard about in the past 5yrs????
None, they all blow up sometime before that. The n2o list is pretty big, the hyper slugs take it well.. If you want to be the one to do it let us know the results.
Last edited by slomarao; 11-23-2010 at 11:09 PM.
11-23-2010, 11:20 PM
#6
Why do motors pop on boost and not nitrous?
Think of how many nitrous motors would be scattered from here to kingdom come if it had to come on the kit every time you floored it or even came up to 2/3 throttle and the bottle never ran out or was disconnected.
It doesn't help that people tune them (turbo engines) as if they were n/a either.
Cylinder pressure is what it is, the piston doesn't care if it came from a bottle or a blower.
Think of how many nitrous motors would be scattered from here to kingdom come if it had to come on the kit every time you floored it or even came up to 2/3 throttle and the bottle never ran out or was disconnected.
It doesn't help that people tune them (turbo engines) as if they were n/a either.
Cylinder pressure is what it is, the piston doesn't care if it came from a bottle or a blower.
11-25-2010, 09:51 PM
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you should be able to make more power with a turbo than a single stage of nitrous on the stock shortblock. 10.7-11.0 or whatever compression is no big deal, you just need to run the right fuel.
having said that, a COMPLETE turbo setup will cost you some coin. lots more than a complete nitrous setup. if you need to feel max power every day of the week go ahead and do a turbo since bottle refills will cost ya. if you make a couple passes every month with no street driving, nitrous may be an option for you.
i have learned if you can make 6-700rwhp, you will be working on the chassis tuning anyways. any more power will be useless on the typical car other than roll racing to 150+.
having said that, a COMPLETE turbo setup will cost you some coin. lots more than a complete nitrous setup. if you need to feel max power every day of the week go ahead and do a turbo since bottle refills will cost ya. if you make a couple passes every month with no street driving, nitrous may be an option for you.
i have learned if you can make 6-700rwhp, you will be working on the chassis tuning anyways. any more power will be useless on the typical car other than roll racing to 150+.
11-26-2010, 04:39 PM
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11-26-2010, 05:42 PM
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11-26-2010, 06:54 PM
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Tuned correctly horsepower and cylinder pressures should have the same effect from either nitrous or boost. But when I nitrous combo is pushing the limits I would say most people run a little better fuel. This is do to the fact that they are not continuously spraying it. A boosted car is under boost more then the nitrous car being sprayed.
Their are to many variables in each combo. A turbo system done right is going to have a larger upfront cost and I would say that will effect how many have tried going each way. It wouldn't surprise me if there are 10 times as many nitrous combos being built or more.
A friend of mine went 140 mph with a boosted 5.3 liter and I'm sure there aren't many if any lt1's with stock pistons running that mph.
All in the combo. Boosted motors can more then double there n/a hp can that be said of a nitrous motor?
Their are to many variables in each combo. A turbo system done right is going to have a larger upfront cost and I would say that will effect how many have tried going each way. It wouldn't surprise me if there are 10 times as many nitrous combos being built or more.
A friend of mine went 140 mph with a boosted 5.3 liter and I'm sure there aren't many if any lt1's with stock pistons running that mph.
All in the combo. Boosted motors can more then double there n/a hp can that be said of a nitrous motor?
11-26-2010, 07:49 PM
#19
I think you may be confusing combustion temperature with intake air temperature.
Combustion temperature is how hot the air and fuel mixture burns once ignited. During normal combustion, this is primarily a factor of the air to fuel ratio, dynamic compression and the fuel type. Richer burns cooler, leaner burns hotter, more compression burns hotter, less compression burns cooler and gasoline (my favorite fuel type) burns at a specific temperature given the pressure and mixture ratio. It has almost nothing to do with how the air got there (nitrous vs. turbo). The compression, tune and the type of fuel determine the combustion temperature during normal combustion.
The intake air temperature (the temperature of the air going into the engine) is increased by a turbocharger and decreased by nitrous oxide but intake air temperature does not correlate directly to combustion temperature at all. The intake air temperature increase is why turbocharged engines are often equipped with a charge cooler of some type. Nitrous oxide released from a high pressure container is in fact an effective charge cooler on its own.
Combustion temperature is how hot the air and fuel mixture burns once ignited. During normal combustion, this is primarily a factor of the air to fuel ratio, dynamic compression and the fuel type. Richer burns cooler, leaner burns hotter, more compression burns hotter, less compression burns cooler and gasoline (my favorite fuel type) burns at a specific temperature given the pressure and mixture ratio. It has almost nothing to do with how the air got there (nitrous vs. turbo). The compression, tune and the type of fuel determine the combustion temperature during normal combustion.
The intake air temperature (the temperature of the air going into the engine) is increased by a turbocharger and decreased by nitrous oxide but intake air temperature does not correlate directly to combustion temperature at all. The intake air temperature increase is why turbocharged engines are often equipped with a charge cooler of some type. Nitrous oxide released from a high pressure container is in fact an effective charge cooler on its own.