Intake casting numbers

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Map63Vette

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So my 318 had a 4 bbl on it when I bought it and I really didn't think much of it, but when I got to looking around I noticed that they pretty much didn't make 318's with a 4 bbl out of the factory (I think there may have been a few cop cars or something with them). So I decided to go pull casting numbers to see what I could find out for the fun of it and to see if I had something off a 273 or a port mismatch from a 340 or 360 intake. The main problem I have is that all the Mopar casting numbers I find are of the format XXXXXXX, but the numbers on my intake are XXXX XX-X with a second number that is five digits. The numbers I have are 2531 15-2 and 03259. When I looked up numbers I saw that there was a 340 4 bbl intake with the casting number 2531915 which is pretty similar in style to my 2531 15-2, but what's the deal? Are my numbers a later style or something? There is a pentastar on the front of the intake as well, so I assume it is a factor Mopar piece as well as the fact that it carries what I assume is probably factory blue paint by the look of it. Any idea why the casting numbers are so different?
 
Yeah, I've seen lists of casting numbers and looked up ones specifically for the intake, but the format is the big issue that I'm having. All the lists I find have a 7 digit casting number on the tables for intakes, but the casting numbers on my intake are a different format in that it's a 4 digit number then a space, then two digits a dash and one more digit. For instance, this site http://www.mymopar.com/intakecastnumb.htm was where I found the material I mentioned before, but my casting number isn't on there. If I ignore format and just put all my numbers together I get 2531152, but that number isn't anywhere to be found. There are some that are close like 2531915 and 2531914, but not mine specifically. Year One mentions the "Galen Govier Casting Number book", but I don't have it. If someone did and could look it up that would be nice.
 
Certainly, sorry they are not terribly good, didn't really want to remove everything for a better picture.

IMAG0058.jpg


IMAG0059.jpg


IMAG0060.jpg


IMAG0057.jpg
 
The 03259 is the date code. Which is June 30, 1970 by my calculations.

Gots to be a 340 intake.


Chuck
 
I think you are correct and I don't have the service manual handy for that year or I would look it up for you. The only thing that bothers me is that I thought for the 1971 model year the 340 used a Thermoquad spread bore carb?? I could be wrong.
 
2531915 shows to be a 1968 340 according to my casting book but your intake isn't in it.

I wonder if your intake could have been for a marine application originally?
 
I was thinking maybe a replacment manifold over the parts counter. This could explain the '68 casting number but '70 casting date.


Chuck
 
Lol, nothing would surprise me at this point. You all pretty much know more about my engine than me at this point. I'm almost hesitant to do anything to it, because by some miracle the thing actually runs pretty well. It all came with the car, so I haven't changed a thing. The whole car seems like it was just a junkyard dog in that there pretty much isn't a single part on it that's original aside from the vin tag, and at times I even wonder on that one, lol. By the vin and what I can make out from appearances it was originally a /6 and I'm guessing auto since a tunnel was welded in (poorly), but it has obviously since been changed. My main concern was whether or not the intake was really a 340 or 360 piece. I'm fairly sure the heads are original to the block (they're some 73 318 head, don't have the numbers in front of me), so I was curious as to whether I might have had a port mismatch.
 
Huh, figures one of the few things I'm lucky on doesn't necessarily help me, lol. The 340 intake on the 318 heads has got to be an interesting fit, I would dang near put money on it that there was zero machining done to make them match. Probably just looked on the shelf or the nearest junkyard small block for a 4 bbl intake and yanked it. I would doubt the carb is native to the manifold either since it's an electric choke. Can you put a Carter Competition AFB on a Thermoquad bore pattern without an adapter plate?
 
Looks to me it sort of matches the numbers for a 340 intake but the last few digits don't. I'm thinking someone bought that at a parts store new as a replacement intake then it ended up on your 318.
 
Huh, figures one of the few things I'm lucky on doesn't necessarily help me, lol. The 340 intake on the 318 heads has got to be an interesting fit, I would dang near put money on it that there was zero machining done to make them match. Probably just looked on the shelf or the nearest junkyard small block for a 4 bbl intake and yanked it. I would doubt the carb is native to the manifold either since it's an electric choke. Can you put a Carter Competition AFB on a Thermoquad bore pattern without an adapter plate?

You can not put anything other than a spreabore carb on a spreadbore manifold without an adaptor. The primaries are too small....
 
68 thru 70 340's had Carter AVS carbs. AFB and Edelbrocks also fit. The port mismatch is not optimum, but it is a power increase. 71 was the first year for the TQ.
 
Thats exactly what it is, I looked it up in my book here and it's a 68-69 340 Intake. Maybe throw some X heads on that thing to match?
 
I'll probably end up with a full rebuild and top end kit in the long run, but it's nice to know I might be able to at least sell what's on it for some decent money. I'll have to keep it in mind though, I wanted to go aluminum heads for weight, but the 340 idea keeps tempting me, lol.
 
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