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Discussion Starter · #1 ·
I was just thinking about te LT5 motor used in corvette ZR1's. Clearly an awesome engine, but here's my question. Did the LT5 have it's own unique engine block? I know it was based off of the LT1 sbc, but the LT5 was an overhead cam engine? If it used a normal LT1 block, what did they do about the hole through the middle where the cam would have gone in an LT1?
 

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wow, I had no idea that was the case. Since it was 5.7 liters, I just assumed it was LT1-based. Thanks for the info!
 

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32V DOHC with a 4" bore. Sorta looks like a TPI unit for the intake, except more runners
 

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Originally posted by ws6fanatic@Dec 30 2003, 05:54 AM
wow, I had no idea that was the case. Since it was 5.7 liters, I just assumed it was LT1-based. Thanks for the info!
It has small block dimensions, just not a small block. 4 inch bore, 3.48 inch stroke.
 

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The engine is so large with the DOHC that it takes up big block room. That is why you don't see a lot of these engines used in swaps. The dern things are to big, and way to expesive.
 

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Originally posted by bigals87z28+Dec 30 2003, 07:03 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (bigals87z28 @ Dec 30 2003, 07:03 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-ws6fanatic@Dec 30 2003, 05:54 AM
wow, I had no idea that was the case.  Since it was 5.7 liters, I just assumed it was LT1-based.  Thanks for the info!
It has small block dimensions, just not a small block. 4 inch bore, 3.48 inch stroke. [/b][/quote]
um...actually....no.

LT5 has 3.90 bore and 3.66 stroke.
Sound familar? Thats the same as an LS1....coincidence?
I doubt it.

Also, that is the same bore:stroke ratio as the 305!

The bore spacing was the same as the sbc at 4.4"

ZR1's are so cool.
 

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The LT5 has a longer stroke than the LS1. The two engines share nothing but bore spacing and bore measurements.

The LT5 didn't use the LT1's block because when the new heads and camshafts were added, the engine was too large to be installed in the C4's engine bay. Engines were mounted from below and the engine was too wide to fit between the frame rails. The LT5 had to be designed from the ground up as a DOHC engine, using 4.40-inch bore centers and a 5.7L displacement to make it "Corvette."
 

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opps :eek: LS1 is 3.62 stoke and LT5 3.66--they are so close I must have got them confused.
 
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