Pure stock 340 Mopar

mike coates · 02-07-2012, 11:09 PM

Todd,
The cam specs come from the NHRA / IHRA engine specs. For the high compression 340's, the specs have the 330 ish duration. They don't match the "advertised" specs. I think Danny Waters Sr. may have the specs. Terry Bell used to have them, but I don't think he does anymore.
They have to be the old specs from before they removed the duration requirements, from like 20 years ago. I have them for the '70 340. I am not sure if they are the same for the earlier ones.
I have an ISKY stock grind that is around 348 @ .050. with .478 lift I think. It is the dwell nose type. The higher lift works because I run the stamped rockers and the ratio is off from the 1.5, so the actual lift at the valve is still a little short. It is supposed to be a good cam for a regular stocker, but I think it is too much for a pure stock. I run stock valve springs per the rules and I only get 6200 - 6300 rpm. If I were to get another, I would get one that works more to that rpm range.
Some time ago, I talked to the guy with the pure stock demon. I think he was only shifting @ 6000 and 4.56 gears and he was running around 12 flat. I don't know what his specs were. But as I said, I built my engine and I think he had someone build his. I know there are probably several items that could be improved on mine.

Mike

02-07-2012, 11:09 PM	#13
mike coates Junior Member Join Date: Jul 2007 Location: Marshall, MI Posts: 33 Likes: 0 Liked 0 Times in 0 Posts	Re: Pure stock 340 Mopar Todd, The cam specs come from the NHRA / IHRA engine specs. For the high compression 340's, the specs have the 330 ish duration. They don't match the "advertised" specs. I think Danny Waters Sr. may have the specs. Terry Bell used to have them, but I don't think he does anymore. They have to be the old specs from before they removed the duration requirements, from like 20 years ago. I have them for the '70 340. I am not sure if they are the same for the earlier ones. I have an ISKY stock grind that is around 348 @ .050. with .478 lift I think. It is the dwell nose type. The higher lift works because I run the stamped rockers and the ratio is off from the 1.5, so the actual lift at the valve is still a little short. It is supposed to be a good cam for a regular stocker, but I think it is too much for a pure stock. I run stock valve springs per the rules and I only get 6200 - 6300 rpm. If I were to get another, I would get one that works more to that rpm range. Some time ago, I talked to the guy with the pure stock demon. I think he was only shifting @ 6000 and 4.56 gears and he was running around 12 flat. I don't know what his specs were. But as I said, I built my engine and I think he had someone build his. I know there are probably several items that could be improved on mine. Mike __________________ Mike Coates TBD Last edited by mike coates; 02-07-2012 at 11:12 PM.