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Discussion Starter · #1 ·
I noticed that we don't have the CTS DI engine in our 2009's,
but rather a DI version of the LY7 found in the 2008 Lambdas.
All along I thought we had the "actual" CTS version.

Here are some pics.
 

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Is it still the same H.P.?
 

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The block and internals should be the same. The manifolds, accessory drives, and exhaust systems are different because of the layouts. CTS rear wheel drive = ---, Lambda's front wheel drive " ----. The CTS DI 3.6 is rated at 304HP.
 

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Discussion Starter · #4 ·
xseler said:
The block and internals should be the same. The manifolds, accessory drives, and exhaust systems are different because of the layouts. CTS rear wheel drive = ---, Lambda's front wheel drive " ----. The CTS DI 3.6 is rated at 304HP.
Good point, makes sense.

I like the oil filter on the CTS better! :thumb:
 

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Discussion Starter · #5 ·
I think this is the fuel pump for the DI, anyone know for sure?
 

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Block wise, there is no difference between the Cadillac LLT and the Lambda LLT. Echoing xselers points, bore x Stroke and cam profiles are the same. Now, the intake manifolds could be different, the exhaust routing is obviously different too, and the ECM programming is likely different to account for the 16 hp difference.

Copperhead, all I could find on the high pressure fuel pump is that it is driven by the exhaust camshaft of cylinder bank 2.
 

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GeoHawk said:
Block wise, there is no difference between the Cadillac LLT and the Lambda LLT. Echoing xselers points, bore x Stroke and cam profiles are the same. Now, the intake manifolds could be different, the exhaust routing is obviously different too, and the ECM programming is likely different to account for the 16 hp difference.

Copperhead, all I could find on the high pressure fuel pump is that it is driven by the exhaust camshaft of cylinder bank 2.
So how much different is the 09 engine in relation to the 07's and 08's and why change it when it seems the two previous year engines are functional
 

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More power and better fuel economy. It probably also helped to lower the cost to Cadillac for this engine since more would be produced.
 

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xseler said:
More power and better fuel economy. It probably also helped to lower the cost to Cadillac for this engine since more would be produced.
Makes sense; too bad the engine wasn't thought of for the earlier models; maybe could have saved some cash
 

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jsimms said:
So how much different is the 09 engine in relation to the 07's and 08's and why change it when it seems the two previous year engines are functional
Expanding on xseler's comments, the two main differences between the LY7 (07-08) and the LLT (09+) are the port injection vs. direct injection and a bump in the compression ratio from 10.2:1 to 11.3:1. The other engine interals have the same specs, from what I could find. The LLT also eliminated the variable stage intake manifold on the LY7. With the LLT engine, you get a roughly a 5% increase in horsepower, a 7.5% bump in torque (and get more of it sooner in the rpm range), plus no fuel mileage penalty that everyone would crucify GM for if they could.

Here's some bathroom reading material ;)

LLT: http://media.gm.com/us/powertrain/en/product_services/2009/Stories/HFV6/09_LLT_n.doc

and http://media.gm.com/us/powertrain/en/product_services/2009/Spec%20Sheet/HFV6/09_LLT_n.xls


LY7: http://media.gm.com/us/powertrain/en/product_services/2008/Whats%20New/HFV6/08_LY7.doc

and http://media.gm.com/us/powertrain/en/product_services/2008/Spec%20Sheet/HFV6/08_LY7.xls
 

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Commenting on Geo's comments, while at the car show this weekend, I heard a guy talking about the motor in his 60's Corvette (I was hearing bits & pieces). It had 11:1 compression and a solid roller cam. He was talking about mixing lead additive with aircraft fuel to get an octane rating around 100.

It's still hard to believe this motor has over 11:1 CR & can run on 87 octane gas.

GM is fairly consistent in making more power from the same motor based on where it ends up. There has usually been a 30+/- HP difference between the 5.7L Camaro and Corvette for quite a while. Chevy usually puts "the good stuff" as far as manifolds & cams on the Corvette motors. I know on the LT1 versions, Corvettes also had 4 bolt mains. I read that the different parts were used to satisfy the egos of the Corvette buyers since the car cost a lot more. :) When I hopped up the 5.3L truck motor in my RX-7, I used a Corvette production cam & springs. In testing by the guy that wrote the LS1 performance book (Wil Handzel, Group Manger of GM Performance Parts) it was good for about 40 peak HP over a stock cam yet gives a decent idle and power band.

:hijacked:
oops. :-X :-[
 

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GeoHawk said:
jsimms said:
So how much different is the 09 engine in relation to the 07's and 08's and why change it when it seems the two previous year engines are functional
Expanding on xseler's comments, the two main differences between the LY7 (07-08) and the LLT (09+) are the port injection vs. direct injection and a bump in the compression ratio from 10.2:1 to 11.3:1. The other engine interals have the same specs, from what I could find. The LLT also eliminated the variable stage intake manifold on the LY7. With the LLT engine, you get a roughly a 5% increase in horsepower, a 7.5% bump in torque (and get more of it sooner in the rpm range), plus no fuel mileage penalty that everyone would crucify GM for if they could.

Here's some bathroom reading material[/color] ;)

LLT: http://media.gm.com/us/powertrain/en/product_services/2009/Stories/HFV6/09_LLT_n.doc

and http://media.gm.com/us/powertrain/en/product_services/2009/Spec%20Sheet/HFV6/09_LLT_n.xls


LY7: http://media.gm.com/us/powertrain/en/product_services/2008/Whats%20New/HFV6/08_LY7.doc

and http://media.gm.com/us/powertrain/en/product_services/2008/Spec%20Sheet/HFV6/08_LY7.xls
Thanks for the info and links; now if I can just figure out how to get this desktop into the bathroom I will be good to go :D
 

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Discussion Starter · #13 ·

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GeoHawk said:
jsimms said:
So how much different is the 09 engine in relation to the 07's and 08's and why change it when it seems the two previous year engines are functional
Expanding on xseler's comments, the two main differences between the LY7 (07-08) and the LLT (09+) are the port injection vs. direct injection and a bump in the compression ratio from 10.2:1 to 11.3:1. The other engine interals have the same specs, from what I could find. The LLT also eliminated the variable stage intake manifold on the LY7. With the LLT engine, you get a roughly a 5% increase in horsepower, a 7.5% bump in torque (and get more of it sooner in the rpm range), plus no fuel mileage penalty that everyone would crucify GM for if they could.

Here's some bathroom reading material ;)

LLT: http://media.gm.com/us/powertrain/en/product_services/2009/Stories/HFV6/09_LLT_n.doc

and http://media.gm.com/us/powertrain/en/product_services/2009/Spec%20Sheet/HFV6/09_LLT_n.xls


LY7: http://media.gm.com/us/powertrain/en/product_services/2008/Whats%20New/HFV6/08_LY7.doc

and http://media.gm.com/us/powertrain/en/product_services/2008/Spec%20Sheet/HFV6/08_LY7.xls
So if I read these reports correctly; are they saying the 08 engine has more horsepower than the 07's?
 

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jsimms said:
So if I read these reports correctly; are they saying the 08 engine has more horsepower than the 07's?
Nah, the 07s and 08s have the same power numbers, but the LY7 in the Lambdas did make more power than the LY7 in other vehicles.
 

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I see; that's probably where I was getting confused
 

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Has anybody seen acceleration figures for the 09? I have them from (Motor trend, I think), for the 07. I am curious if the extra ponies made a difference.
 

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sandman said:
Has anybody seen acceleration figures for the 09? I have them from (Motor trend, I think), for the 07. I am curious if the extra ponies made a difference.
I have an 07, can you send me the figures you have; thanks in advance
 

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jsimms said:
sandman said:
Has anybody seen acceleration figures for the 09? I have them from (Motor trend, I think), for the 07. I am curious if the extra ponies made a difference.
I have an 07, can you send me the figures you have; thanks in advance
Use this link - http://www.caranddriver.com/buying_...e-reviews_by_make+mode-collection+id-266.html

Look for downloads[/color] about half way down the first page and click the "spec sheet"

Couldn't find any acceleration figures for the 09 in the car and driver review (outside of being second in the quarter mile) - so if anybody else has seen any let me know.
 

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Thanks for the link
 
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