DI (Direct Injection) Fuel System
Thread Starter
Race Director
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From: Missouri City, TX
DI (Direct Injection) Fuel System
I am considering buying a 2010 Cadillac CTS Sport Wagon for my wife's next DD. The Caddie 3.0L and 3.6L V6 engines are DI for "direct injection". How is DI different from the fuel injection on our corvette LS engines. I gather that DI is newer engine technology than what is on the LS engines now. Just a brief summary of what it is would be appreciated from the engine gurus here.
Drifting
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From: Melbourne, Arkansas
Cruise-In X Veteran
I am considering buying a 2010 Cadillac CTS Sport Wagon for my wife's next DD. The Caddie 3.0L and 3.6L V6 engines are DI for "direct injection". How is DI different from the fuel injection on our corvette LS engines. I gather that DI is newer engine technology than what is on the LS engines now. Just a brief summary of what it is would be appreciated from the engine gurus here.
Mark
Team Owner
Joined: Feb 2001
Posts: 27,254
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From: Short Hills, NJ
I'm really hoping that the C6's LS3 will get Direct Injection in the near future, should make for a nice bump in power and would be especially appropriate if the Z06 were to ever be dropped from the line up.
Melting Slicks
Joined: Mar 2008
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From: Avon Park FLORIDA
St. Jude Donor '08-'09-'10
it would be 
if they would do that, Ls motors would pickup HP and MPG!!
Drifting
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From: Melbourne, Arkansas
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From: Missouri City, TX
Direct Injection puts the fuel directly into the cylinder and under very high pressure, around 2800psi. Regular fuel injection the fuel is injected into the intake by the intake valve and is pulled into the cylinder by the down stroke of the piston. Using direct injection they can bring the compression ratio way up without the risk of detination. I had a Pontiac Solstice GXP and it came with a 2.0 liter (122 Cubic Inches) turbo charged direct injected engine. It ran up to 18 psi of boost from the factory and made 260 hp. That is over 2 hp per cubic inch
Mark
Mark
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From: Charlotte, NC (formerly Endicott, NY)
DI probably is coming to the Corvette. At the last ALMS race of the season last year the other manufacturers protested the Corvette team using DI in their GT2 car because it gave them a 20 HP advantage. They can use it this year with the new 5.5L engine and after a while it will probably come to a street Corvette. It is a way of increasing power or keeping your power level and getting better gas mileage.
Bill
Bill
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From: Missouri City, TX
FYI - I ordered a 2010 Cadillac CTS Sport Wagon with 3.6L DI engine from Kevin Will at Les Stanford Chevy-Cadillac yesterday for my wife's DD. Les Stanford is a Forum Supporting Dealer. Thank you Kevin for making this purchase very easy.
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From: Cumming Ga
Thread Starter
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From: Missouri City, TX
Thanks for posting this. Will a DI engine be more or less likely to require a Top Tier gasoline which has a high level of detergency for keeping the injectors clean? I am thinking more likely.
Supporting Vendor
Joined: Mar 2008
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From: Cumming Ga
with a input pressure of 1600 psi these will never get dirty.. we do a lot of service on gdi for marine and never see any clogged. the only problem is on modding these engines as there is only a few sizes available,, So when the ls3 starts using GDI, I would guess we will need a secondary fuel system and additional injectors. Or find a way to change the flow rate as we have done with conventional injectors. Also remember that these GDI engines run at 30-40 a/f ratio in cruise mode so there will be a whole new generation of tuner software, maybe. We are not really looking forward to this
