LS5 long block value?

[Rixls6]

If it's an original LS5 from a 70 Chevelle, then the code should be CRT. Chances are it's out of a car from Atlanta and would have the partial VIN stamped on the front pad also, like: 10Axxxxxx

If it was a Van Nuys built car, then the partial VIN would be down by the oil filter.

[ANDY M]

According to Colvin, the "512" block was the only Chevy block used as both a '69 427 and '70 454, since GM had already made the decision to increase the stroke for the '70. This casting was also made with both 2 bolt and four bolt mains, and used in the big Chevys and 'Vettes in '69, and Chevelles added in '70.

[Andy]

T0904CRN is what is stamped on the front pad. So it would be Tonowanda Engine Plant, September 4th and according to the big block engine suffix codes on http://www.nastyz28.com/gm-chevy-cod...-suffix-12.php, this is what it came out of.

CRN 1970 Chevelle 454 360hp manual trans LS-5

[Andy]

I've seen two different hp levels with this engine as well, 360 hp and 390 hp, which is correct?

[Mr70]

Are you sure it's CRN?,I think that's out of a 1970 Monte Carlo with an LS-5/360HP M/T originally.
390HP was for the Corvette & Passenger series & Police/Taxi vehicles.
Are you sure it's not CRT?

[Andy]

Yes, it's CRN. The source I had on www.nastyz28.com led me to believe that it was a 4 speed chevelle motor. It still had the manual trans flywheel on it, and he still has the 11" 621 bellhousing that came off of it too, so I thought the info was accurate. I asked about it on the chevelle board too and they said the same thing about it being a Monte Engine. I did a search on the Monte Carlo website and it said CRN designates a 454 Monte engine. Thanks for the info Mr70.

[Rixls6]

CRN is 70 Monte Carlo 454 with a Turbo 400, NOT 4-speed.