Concept Performance LSR - anyone used?

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Dec 29, 2021 | 11:05 AM

#21

NicD

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From: Chandler, AZ

Quote:

Originally Posted by SLOW SEDAN

I sure did... maybe you should see below:

1500 crank max, yeah no engine builder is going to recommend a stock block for that application. Anyways, continue on...

Dec 29, 2021 | 11:19 AM

#22

SLOW SEDAN

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From: No VA

Quote:

Originally Posted by NicD

1500 crank max, yeah no engine builder is going to recommend a stock block for that application. Anyways, continue on...

You are hung up on recommendations, but you obviously don't know every engine builder. Guess it really gets in your feels when a totally stock bottom end combo makes over 1300 crank

A forged bottom end is easily capable of 200hp more whether your shop and builder recommend it or not.

Dec 29, 2021 | 11:29 AM

#23

SLOW SEDAN

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From: No VA

Quote:

Originally Posted by JimTA

It's hard to know what I have will take. Read one post and I am already 400hp over what it will handle then others say it will live to a million HP... I guess it is a sickness and feel I need to be building something.. should probably run it til it dies then I have my answer.. I have the charge pipe issue addressed.

I get it! If I went by peoples "recommendation" on what worked and what didn't my SBE 5.3 would have blown up 10 years ago with 35PSI... but it didn't. Shops are just scared if word gets out something they worked on blows up they get a bad name on facebook or whatever. The real thing is when you beat their $50k shop build with a SBE 5.3 they get way more negative press

BTW I totally get the need to build something sickness! I always say build to your budget, don't let the build cost more than you are willing to lose.

Dec 29, 2021 | 11:52 AM

#24

ddnspider

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From: FL

Quote:

Originally Posted by JimTA

4" bore - opens options for heads and better airflow. figure I need less boost and less overall stress on motor/head gaskets with more inches. running a 5.3 through numbers with garret maps will take a lot of boost vs the inches, about 10lbs at 7000rpm for same HP...
Currently running 4" stroked LS1 block with K1 forged bottom and Wiseco pistons.. twin Garret 3684's (6266's).. made it to track for last run of the year and ran a 5.79 with a 1.31 60'... plugs show timing and fuel were good but I kept blowing charge pipe off at 26lbs (had wastegate not opening all the way and creeped on me) my goal is only 5.50 and will likely hit that first time out next season with some more boost on launch I think.. I am just looking to start on a short/long block to prepare for the inevitable and want to leave the door open for more in the future.. honestly if the Darts were sitting on the shelf I guess I would just go that route and call it done.

4 inch bore is nice, but I wouldn't get hung up on keeping the boost number down unless your class limited in size and the boost required to hit the power goal pushes you outside the efficiency range. I'd want as thick as possible between bores even if it means running more boost. The combustion pressure is what it is for a given power level regardless if it took 5 psi more or less to get there.