Turbo with 10.8:1 comp. pistons??
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From: soon to banned as I am from MANITOBA?
Turbo with 10.8:1 comp. pistons??
The following is GM specs for the 2.2 performance team drag car.
Engine Type : Inline 4-cylinder
Displacement : 2.2 Liters, 3.500" bore, 3.505" stroke
Valves/cylinder : 4
Balance Shafts : Removed for high RPM operation
Block Material : Aluminum with steel cylinder liners
Head Material : Aluminum
Crankshaft : Billet Steel
Compression : 10.8:1
Camshafts : Custom ground, with roller valve finger followers
Induction : AirWerks by BorgWarner Turbocharger with air to water intercooler
Ignition : Capacity discharge by MSD
Fuel Delivery : Pectel T-10
Lubrication : Dry sump
Exhaust : 4 into 1, custom bent
Horsepower : 1250hp @ 9200rpm
Torque : 800 lb-ft @ 8000rpm
Transmission : X-Trac seqential
When ever I talk of replacing pistons people tell me to go lower compression to do a turbo one day. In the compact build book the suggest 8:1 or 9:1. and yet this build has 10.8:1 and GM did a build of an LSJ to be over 300HP with 10:1 pistons. Now obviously something in the recipe dictates the way to go. Help me out. I was planning on building up to the max with bolt ons as I dare to go. then pistons. then do the rest (head, cams, twin or turbo charged) anyone with thoughts about this.
Engine Type : Inline 4-cylinder
Displacement : 2.2 Liters, 3.500" bore, 3.505" stroke
Valves/cylinder : 4
Balance Shafts : Removed for high RPM operation
Block Material : Aluminum with steel cylinder liners
Head Material : Aluminum
Crankshaft : Billet Steel
Compression : 10.8:1
Camshafts : Custom ground, with roller valve finger followers
Induction : AirWerks by BorgWarner Turbocharger with air to water intercooler
Ignition : Capacity discharge by MSD
Fuel Delivery : Pectel T-10
Lubrication : Dry sump
Exhaust : 4 into 1, custom bent
Horsepower : 1250hp @ 9200rpm
Torque : 800 lb-ft @ 8000rpm
Transmission : X-Trac seqential
When ever I talk of replacing pistons people tell me to go lower compression to do a turbo one day. In the compact build book the suggest 8:1 or 9:1. and yet this build has 10.8:1 and GM did a build of an LSJ to be over 300HP with 10:1 pistons. Now obviously something in the recipe dictates the way to go. Help me out. I was planning on building up to the max with bolt ons as I dare to go. then pistons. then do the rest (head, cams, twin or turbo charged) anyone with thoughts about this.
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Joined: 04-17-04
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From: Calgary Alberta Canada
well for one---they are using some seriously high octane race gas.
Wonder how much boost it runs?
Compression ratios and lbs of boost has both been steadily going up for years on production cars.
Wonder how much boost it runs?
Compression ratios and lbs of boost has both been steadily going up for years on production cars.
I'm old school
Joined: 02-16-05
Posts: 6,905
Likes: 3
From: Nashville
I am the man you need to talk to.
You are confusing a street machine with a race engine.
The car described above is a race machine that can never be legally operated on the street. The car uses Methanol, not gasoline, and only runs for about 10 seconds at a time. Therein lies your answer.
It's all about the gasoline. A street emmisions legal car can only use the highest octane pump gas that they sell at the local gas station. Sure, there are higher octanes, and sure, people use them on the street, but isn't legal to do so.
If you want a street machine, you have to design your engine around the street legal gas available to you, usually around 93 octane depending on where you live.
With that limiting factor, build you engine. A forced induction engine using 93 octane will be able to handle a larger amount of boost with a smaller compression ratio without pre-ignition or detonation. The idea being, get as much air and gas into the cylinder as you can and compress it as much as you can without the gas exploding. A nice, stable running engine that will be reliable and streetable.
Does that answer your question?
You are confusing a street machine with a race engine.
The car described above is a race machine that can never be legally operated on the street. The car uses Methanol, not gasoline, and only runs for about 10 seconds at a time. Therein lies your answer.
It's all about the gasoline. A street emmisions legal car can only use the highest octane pump gas that they sell at the local gas station. Sure, there are higher octanes, and sure, people use them on the street, but isn't legal to do so.
If you want a street machine, you have to design your engine around the street legal gas available to you, usually around 93 octane depending on where you live.
With that limiting factor, build you engine. A forced induction engine using 93 octane will be able to handle a larger amount of boost with a smaller compression ratio without pre-ignition or detonation. The idea being, get as much air and gas into the cylinder as you can and compress it as much as you can without the gas exploding. A nice, stable running engine that will be reliable and streetable.
Does that answer your question?
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Joined: 07-14-06
Posts: 162
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From: OK
Originally Posted by Halfcent
I am the man you need to talk to.
You are confusing a street machine with a race engine.
The car described above is a race machine that can never be legally operated on the street. The car uses Methanol, not gasoline, and only runs for about 10 seconds at a time. Therein lies your answer.
It's all about the gasoline. A street emmisions legal car can only use the highest octane pump gas that they sell at the local gas station. Sure, there are higher octanes, and sure, people use them on the street, but isn't legal to do so.
If you want a street machine, you have to design your engine around the street legal gas available to you, usually around 93 octane depending on where you live.
With that limiting factor, build you engine. A forced induction engine using 93 octane will be able to handle a larger amount of boost with a smaller compression ratio without pre-ignition or detonation. The idea being, get as much air and gas into the cylinder as you can and compress it as much as you can without the gas exploding. A nice, stable running engine that will be reliable and streetable.
Does that answer your question?
You are confusing a street machine with a race engine.
The car described above is a race machine that can never be legally operated on the street. The car uses Methanol, not gasoline, and only runs for about 10 seconds at a time. Therein lies your answer.
It's all about the gasoline. A street emmisions legal car can only use the highest octane pump gas that they sell at the local gas station. Sure, there are higher octanes, and sure, people use them on the street, but isn't legal to do so.
If you want a street machine, you have to design your engine around the street legal gas available to you, usually around 93 octane depending on where you live.
With that limiting factor, build you engine. A forced induction engine using 93 octane will be able to handle a larger amount of boost with a smaller compression ratio without pre-ignition or detonation. The idea being, get as much air and gas into the cylinder as you can and compress it as much as you can without the gas exploding. A nice, stable running engine that will be reliable and streetable.
Does that answer your question?
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From: soon to banned as I am from MANITOBA?
Originally Posted by avro206
well for one---they are using some seriously high octane race gas.
Wonder how much boost it runs?
Compression ratios and lbs of boost has both been steadily going up for years on production cars.
Wonder how much boost it runs?
Compression ratios and lbs of boost has both been steadily going up for years on production cars.
I think I read that they run 42 to 45psi and have the capability to run just over 50psi. I feel I am being conservative about these numbers but I know I could be way off. It has been quite a while since I read that. I dont feel like pulling out the build book right now LOL.
Thread Starter
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Joined: 03-14-06
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From: soon to banned as I am from MANITOBA?
Originally Posted by Halfcent
I am the man you need to talk to.
You are confusing a street machine with a race engine.
The car described above is a race machine that can never be legally operated on the street. The car uses Methanol, not gasoline, and only runs for about 10 seconds at a time. Therein lies your answer.
It's all about the gasoline. A street emmisions legal car can only use the highest octane pump gas that they sell at the local gas station. Sure, there are higher octanes, and sure, people use them on the street, but isn't legal to do so.
If you want a street machine, you have to design your engine around the street legal gas available to you, usually around 93 octane depending on where you live.
With that limiting factor, build you engine. A forced induction engine using 93 octane will be able to handle a larger amount of boost with a smaller compression ratio without pre-ignition or detonation. The idea being, get as much air and gas into the cylinder as you can and compress it as much as you can without the gas exploding. A nice, stable running engine that will be reliable and streetable.
Does that answer your question?
You are confusing a street machine with a race engine.
The car described above is a race machine that can never be legally operated on the street. The car uses Methanol, not gasoline, and only runs for about 10 seconds at a time. Therein lies your answer.
It's all about the gasoline. A street emmisions legal car can only use the highest octane pump gas that they sell at the local gas station. Sure, there are higher octanes, and sure, people use them on the street, but isn't legal to do so.
If you want a street machine, you have to design your engine around the street legal gas available to you, usually around 93 octane depending on where you live.
With that limiting factor, build you engine. A forced induction engine using 93 octane will be able to handle a larger amount of boost with a smaller compression ratio without pre-ignition or detonation. The idea being, get as much air and gas into the cylinder as you can and compress it as much as you can without the gas exploding. A nice, stable running engine that will be reliable and streetable.
Does that answer your question?
I am mechanically enclined (for a back yard tech) and have managed auto repair shops plus one years apprentichship. I know quite a bit about cars and threories. Point being my opinion of your explanation is backed with some knowledge. I have racing experience too, but in motorcycles.
This is all new territory. I thank you for giving light to the situation.
GM and JBP are still recommending 10:1 and some people are doing 10.5:1. JBP knows what they are doing and I would follow their recommendations but I still want to understand.
Now with your explanation I am thinking to myself "whoa, I am definitely not going to the 10.5:1 and I really need to see how victory red SS's car turns out.
I thought of twin charged like this fella is doing but I am willing to get as much HP out of it with the factory blower. but the world is for ever changing and so will my mind LOL.
thanks.
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