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Discussion Starter · #1 ·
I am not going to debate the feasibility, I am asking merely what would be a good match being one that would be able to spool quickly and achieve a little over 200wbhp. I am aware of the of the modified turbos from VTuner and BNR but what fun would that be. Thread is meant to be a discussion, not a plan of development.
 

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Would be cool to mount a t28 on the 1.4 those were upgrade turbos for Nissan 300zx's. The 300zx's were 3.0L engines with twin turbos. So, one would be good for a 1.4 4 cly
 

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Already getting a peak turbo pressure from the stock Cruze as high as 35 psi. How much do you want? And can that little 1.4 L engine handle more without throwing a rod through the side of the block.

Normally a turbo upgrade includes a completely remodification of the engine itself, plus the intake and the exhaust. If in the USA, these modifications require complete certification from the EPA for street use. But okay just for the track.

Could buy one of these, but still can only drive it at 55 mph on the road.



In my state, exceeding the speed limit by just 20 mph and getting caught will take your driver's license away for a year, and watch your insurance rates skyrocket when you get it back, if you get it back.

This is not hard to do went leaving a town with a 25 mph speed limit and seeing a sign ahead at 45 mph. If you hit 46 mph before passing that sign, already exceeded the speed limit by 21 mph. Suppose to drive at 25 mph until you pass that sign.

If you see any old vehicle along side of the road, make darn sure you are driving at 25, it will follow you with flashing lights, cops are playing it dirty today. Call themselves undercover cops.
 

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Jerry uses a brand new turbo core, and actually makes a ton of power. I'd have to find the dyno. Not only does it spool faster, but it keeps pulling harder all the way to redline. Any other turbo will have trouble with the "under the curve" power band. The catch of course is that you need new valve springs or you WILL get valve float.
 

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Discussion Starter · #5 ·
Already getting a peak turbo pressure from the stock Cruze as high as 35 psi. How much do you want? And can that little 1.4 L engine handle more without throwing a rod through the side of the block.
I wasn't aware that stock turbo psi peaked pretty high, but how long can the turbo run at that boost pressure without damaging itself.


Jerry uses a brand new turbo core, and actually makes a ton of power. I'd have to find the dyno. Not only does it spool faster, but it keeps pulling harder all the way to redline. Any other turbo will have trouble with the "under the curve" power band. The catch of course is that you need new valve springs or you WILL get valve float.
If you could find the dyno graph, that would great because I didn't see one on BNR's site, and I know Vtuner sells upgraded valve springs so that does sound like the way to go, and I have no doubt Jerry makes a great product! However, it would be awesome if there were custom turbo manifolds for the cruze, for the people who like to have a complete custom setup.

I wonder if we could twin charge the cruze, where we
 

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1.6 HP per cubic inch of displacement that the 86 CID Cruze engine has for a stock production engine with a 100K mile warranty isn't very bad. Some very exotic engines hit 5 HP per cubic inch of displacement, but are only good for a couple of hours of racing and have to be completely overhauled. And certainly not using convenience store pump gas.

A turbo can be looked at in two different ways, for the Cruze to recovered a small portion of that wasted exhaust heat where about 85% of the energy is not being used to operate the engine, but causing global warming. The Cruze is classified in the mpg race.

Another is increased performance, but a turbo does have limitations, more like a bell shaped curve. The more boost it produces, the more restriction it adds to the exhaust so performance will suffer over that peak. It has to be optimized for both fuel economy and performance.

For the big stuff, a supercharger is far better driven by the engine crankshaft, but for an 8,000 HP engine, that supercharger would consume about a thousand of that HP just to run it. Just about everything is a tradeoff in engineering, and for a "cheap" vehicle like the Cruze, manufacturing cost enters the equation.

HP = Torque X RPM/5252, torque is mostly gained by increasing displacement, some motorcycle racing engines run at 17,000 rpm, another way to gain more power, but have to be geared down substantially. Piston and bearing friction also increase exponentially, another tradeoff, forget about durability and engine life.

Also compressing air produces a lot of heat so intercoolers are required, the restrictions of the plumbing become a very strong consideration.

Unleaded gas is a major problem, but beats using leaded gas that explains why we have so many nuts today. Its combustion chamber is 2,600*F that can fry exhaust valves in a hurry and put large holes in your pistons. To counter this, either an EGR valve is used, problems with buildup, or the exhaust valves are closed early in the case of the Cruze. But this can effectively decrease your displacement by as much as 30% making 1.6 HP per cube even a lot more attractive.

Water injection would be far more superior, but not for the average vehicle driver that don't even know how to fill their own gas tank let alone anything about what is under the hood. Only thing the EPA can talk about is excess NOx emissions, nothing about frying up your engine.

A ton of books have been written on this subject since 1885, should do some reading first before asking questions, and never will get a straight answer.
 

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Oh, another thing they don't tell you, practically of vehicles for the last 15 years or so have spy boxes installed, know exactly how you are driving your vehicle. Claim it is for improving safety, but can be used against you in a court of law if involved in an accident.

Big brother is riding along side of you. You don't see him, but he is definitely there.
 

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I wasn't aware that stock turbo psi peaked pretty high, but how long can the turbo run at that boost pressure without damaging itself.




If you could find the dyno graph, that would great because I didn't see one on BNR's site, and I know Vtuner sells upgraded valve springs so that does sound like the way to go, and I have no doubt Jerry makes a great product! However, it would be awesome if there were custom turbo manifolds for the cruze, for the people who like to have a complete custom setup.

I wonder if we could twin charge the cruze, where we
Stock boost is up to 16 PSI - or as much as needed below that cap to hit the 148 ft-lb torque target.

It can run 22-23 before the turbo passes its efficiency curve and anything more is pretty much useless.

Some have gone to great lengths to custom fab headers and get various Garrett and Mitsubishi turbos to fit, but most have said in the end that "it isn't worth it".
 

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Turbo boost gauges use a restrictor to read average boost pressure. Intake manifold pressure is nothing like average with valves opening and closing all the time. Need a high response time electronic pressure tester with a good scope to read peak pressures.

If you remove the restrictor from a turbo gauge, that needle will be bouncing all over the place and for all practical purposes, unreadable.
 

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Discussion Starter · #10 ·
1.6 HP per cubic inch of displacement that the 86 CID Cruze engine has for a stock production engine with a 100K mile warranty isn't very bad. Some very exotic engines hit 5 HP per cubic inch of displacement, but are only good for a couple of hours of racing and have to be completely overhauled. And certainly not using convenience store pump gas.

A turbo can be looked at in two different ways, for the Cruze to recovered a small portion of that wasted exhaust heat where about 85% of the energy is not being used to operate the engine, but causing global warming. The Cruze is classified in the mpg race.

Another is increased performance, but a turbo does have limitations, more like a bell shaped curve. The more boost it produces, the more restriction it adds to the exhaust so performance will suffer over that peak. It has to be optimized for both fuel economy and performance.

For the big stuff, a supercharger is far better driven by the engine crankshaft, but for an 8,000 HP engine, that supercharger would consume about a thousand of that HP just to run it. Just about everything is a tradeoff in engineering, and for a "cheap" vehicle like the Cruze, manufacturing cost enters the equation.

HP = Torque X RPM/5252, torque is mostly gained by increasing displacement, some motorcycle racing engines run at 17,000 rpm, another way to gain more power, but have to be geared down substantially. Piston and bearing friction also increase exponentially, another tradeoff, forget about durability and engine life.

Also compressing air produces a lot of heat so intercoolers are required, the restrictions of the plumbing become a very strong consideration.

Unleaded gas is a major problem, but beats using leaded gas that explains why we have so many nuts today. Its combustion chamber is 2,600*F that can fry exhaust valves in a hurry and put large holes in your pistons. To counter this, either an EGR valve is used, problems with buildup, or the exhaust valves are closed early in the case of the Cruze. But this can effectively decrease your displacement by as much as 30% making 1.6 HP per cube even a lot more attractive.

Water injection would be far more superior, but not for the average vehicle driver that don't even know how to fill their own gas tank let alone anything about what is under the hood. Only thing the EPA can talk about is excess NOx emissions, nothing about frying up your engine.

A ton of books have been written on this subject since 1885, should do some reading first before asking questions, and never will get a straight answer.

Thanks for putting that time writing this up, very helpful.
I am currently running water/meth injection, I am trying to figure out what I want to do to increase the bottom end power a bit. I wonder if we could fit a procharger on the Cruze to reduce the turbolag.
 

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Thanks for putting that time writing this up, very helpful.
I am currently running water/meth injection, I am trying to figure out what I want to do to increase the bottom end power a bit. I wonder if we could fit a procharger on the Cruze to reduce the turbolag.
What lag? There is hardly any - the turbo is about the size of your fist and spools close to 2000 rpm, less on the auto.

If you feel a sharp power drop off below 2500, you're losing power to preignition. Look up the thread here called "hesitation gone"
 

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In theory at least, water/meth injection should replace the need for exhaust gas recirculation, meaning in the Cruze to extend the dwell of the exhaust valves so a greater amount of air fuel can get in. This would definitely make a difference in performance.

Easy job in the 70's years vehicles, just put a plate over the EGR valve and plug the venturi feed tube. Won't be to easy to do in the Cruze, camshaft reground and fooling around with the tune.
 
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