Fergdog65 Posted May 29, 2016 Share Posted May 29, 2016 Can anyone help me identify/verify this block? It has the last 4 casting numbers ground and stamped "3512". It's stamped T0129CRN, 188153794. It was cast L15 9. I have found where GM did restamp some early blocks, but my question is the the vin stamp. I would think it should be stamped 10"Letter"153794. Does this block have any value to restorers? I plan to use it for a Nova build. Quote Link to comment Share on other sites More sharing options...
lastss Posted May 29, 2016 Share Posted May 29, 2016 Looks to be a definite re stamp. As far as value only one could guess, No one who would be doing a show condition would want it. My 2cents Quote Link to comment Share on other sites More sharing options...
LS5 Posted May 29, 2016 Share Posted May 29, 2016 Sam, That is NOT the font and Die spacing that GM would have used to restamp any block. that part of the block that has the numbers missing is not a Stamped number its a casting poured number. there fore restamping over it GM would not do but someone who has a 1969-1972 402 block casting number 3969854 would shave off the last 4 numbers and try very poorly to stamp 3512 in it to pass a 402 off as a 454. Thats my guess and all the years I worked at GM and have dealt with these engines. my guess is that its a 1969 402 made to look like a 454. the heads and intake will all match if they are dated correct and will also lead you to find out what engine it is. Is it still worth anything...... Oh yeah it is, even a date coded 402 for 69 or 70 would be worth something. you can use it in your Nova and pass it off as a 396. GM used in the Chevelle and Nova the 396 which is basically the 402 that they used in the monte carlo in 1970 as well. Darren 1 Quote Link to comment Share on other sites More sharing options...
Fergdog65 Posted May 29, 2016 Author Share Posted May 29, 2016 ncrs.org has a thread of the exact same block done the same way. It's called "casting number ground off!!" 2006 I'm not sure why anyone would grind a casting number and stamp it. That's kinda obvious. Quote Link to comment Share on other sites More sharing options...
496Bowtie Posted June 1, 2016 Share Posted June 1, 2016 While we are on the subject of engine ID... I'm trying to match the LS5 in my '70 SS but there is not a partial VIN on the engine pad stamp, only T1208CRN. Did they use another location? As for date code I see "HI PERF PASS" and a "K" near the oil filter but no 2 digit number after the "K". Barry Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted June 1, 2016 Share Posted June 1, 2016 sometime the VIN is down by the oil filter 1 Quote Link to comment Share on other sites More sharing options...
John S Posted June 1, 2016 Share Posted June 1, 2016 According to chevellestuff.net CRN is the suffix code for 1970 454 360 HP with 400 trans specific to Monte Carlo only. John S Quote Link to comment Share on other sites More sharing options...
gronlit Posted June 4, 2016 Share Posted June 4, 2016 My 70ss is stamped by the oil filter Quote Link to comment Share on other sites More sharing options...
rsorg Posted June 4, 2016 Share Posted June 4, 2016 Try right behind the alternator ,on the block there is a flat area about a half inch wide and 3 inches long ,it is on the block and on an angle ,get a wire toothbrush to clean off the paint ,dirt ,rust ,that is where I have one on my 72 monte carlo custom, with 454,Roger Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted June 4, 2016 Share Posted June 4, 2016 a lot of the 1970 and earlier were stamped by the oil filter Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted December 18, 2016 Share Posted December 18, 2016 Group, When I search the various engine suffix code sites/lists, i find that there are several codes for the 71SS, but I found none for the 70. all of the sites i have seen show CRN as a 70' Chevelle with a M/Trans. Do we know CRN is correct? (I'm REALLY hoping because thats what I have ha). Mike Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted December 18, 2016 Share Posted December 18, 2016 I do see the Chevelle stuff site, and the pic of the CRN code, noted as Monte Carlo only. all of the others I've found list Chevelle. weird Quote Link to comment Share on other sites More sharing options...
LS5 Posted December 18, 2016 Share Posted December 18, 2016 The GM Heritage Website lists CRN and CRQ as 1970 454 with TH400 as Monte Carlo Blocks. also picture of Gang Stamp they used [/u RL] I am thinking that block you have may have been a 3969854 which was a 396/402 block ground off and tried to be passed off as a 512 ?? Just guessing Darren Quote Link to comment Share on other sites More sharing options...
LS5 Posted December 18, 2016 Share Posted December 18, 2016 Easiest way to find out on that Block I just noticed is the Last of the VIN that is stamped on the engine. the 15 denotes as Canadian. GM Canada at the Oshawa Plant keeps all GM history on file. It will cost you about $75 USD but giving them that last part of the VIN they should be able to tell you what Car it was and what size that engine was for sure then you know 454 or 396/402.......... The vin will get them the details whether it was a SS car or a 402 car. Darren. Quote Link to comment Share on other sites More sharing options...
riverdogs00 Posted December 18, 2016 Share Posted December 18, 2016 my stamp reads T0317CRN Quote Link to comment Share on other sites More sharing options...
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