03-29-2021, 10:52 AM | #1 |
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LT1 versus LT4 GM standard block build
edit: Stupid idea, I forgot the LT4 low compression pistons are part pf the short block.
I have this offbeat idea that some of you engineers and GM folks might be able to flush out (or flush down ) What would the $$ or practical limitation be to use the same block build for the LT1, LT2, and LT4? In other words if all the LT blocks have the good stuff how much more does that cost to go LT4? And would simplifying the two build processeses to one save some of those $$ back for the more expensive parts and block casting? This might also save warranty work to some extent with stronger internals. But I suppose the LT4 block also might need more of an assemblers manual attention/time. Like all SSes have track cooling which is used by (guessing here) 10% of Camaro owners including the 1LEs could this another plus for SSes? Espcially if you track.
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03-29-2021, 11:58 AM | #2 |
Drives: Turbo 6.2 Join Date: Feb 2019
Location: Buffalo
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Good question. I've heard the blocks and heads are different material but I dont know. Looks like the vendors use lt1 blocks for most of their stroker engines they sell.
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2016 Turbo Camaro SS - 800hp/900tq 9.7@146
2018 LTZ Z71 Redline Silverado - 381hp/420tq 13.8@100 |
03-29-2021, 04:02 PM | #3 |
Drives: 2021 Camaro ZL1 A10 Join Date: Nov 2018
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I'm not sure if you're just referring to the block casting itself, or the short block, or the long block. That said, the LT1 and LT4 blocks are similar, but the LT4 has additional pressure relieving holes in the lifter valleys to help allow for better oil draining. I'm not sure what other minute differences there are, but I'm sure there are others.
Practically everything that bolts up to the block itself, however, as I'm sure you're aware, is upgraded or improved over the LT1, so making the LT4 short block or long block into a standard LT1 would be too expensive. For example, the forged LT4 crank is stronger than the forged LT1 crank (which fails when subjected to extreme tests at LT4 power levels). The LT4 heads are Rotocast 656T6 alumimum - a stronger casting method and a stronger material itself. Of course, there's many other differences in the long blocks as well.
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03-30-2021, 09:16 AM | #4 | |
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
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Quote:
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03-30-2021, 12:06 PM | #5 | |
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Quote:
I wonder if the LT4 short block is heavier?
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07-21-2021, 07:32 PM | #6 |
Drives: SS 6 speed of course Join Date: Jan 2016
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Clevite LSx bearings are suppose to fit with "minor work to the block". That scared me away but I have plenty time how to work on it.
https://www.texas-speed.com/p-5649-t...-assembly.aspx The Lt4 crank's 7/8 rod journal is solid (not drilled) as testing showed the LT1 crank to weak under boost at that location. This looks like a standard thrust bearing to me: https://www.lsxceleration.com/king-x...oil-clearance/ I don't remember off hand but I thought the cap had the cut for a full radius thurst. The real problem being is the cap can walk on the block which can cause the two thrust surfaces to be messed up. ARP studs? dunno, I studded my block, which is mandatory. Since the design was only for 1/2 radius I can see the cap side not being machined correctly, just "good enough" from the factory. I wonder if the Voodoo engine has a full radius thrust?
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08-02-2021, 06:32 AM | #7 |
Drives: Hyper Blue 2016 2SS 6M Join Date: Sep 2017
Location: North Ga
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Parts commonality is a good thing, generally speaking, and if Camaro was the only platform using the 6.2L, I wouldn't be surprised if the advantages of maintaining the parts, tools, plans, etc. Would offset the slightly higher costs of the LT4. However, since the trucks/suvs use the same longblock as the LT1, the math to support one configuration no longer works.
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08-02-2021, 07:40 AM | #8 |
Drives: Turbo 6.2 Join Date: Feb 2019
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I completed a LT4 swap into my SS. The heads are very different. I want to say the blocks might be a little different in the water jacket webbing around the cly. I don't remember though. If I have time, I'll look through pics and see if I can find something.
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2016 Turbo Camaro SS - 800hp/900tq 9.7@146
2018 LTZ Z71 Redline Silverado - 381hp/420tq 13.8@100 |
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