donald smith
Member
can the casting snub b removed for pump clearence passenger side engineblock 340
fuelpump clearence issue
- Thread starter donald smith
- Start date
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We need pictures to see what you are referring to.
This is a first for me! Never heard of fuel pump clearance issues
Rat Bastid
Dunamis Metron
Yes, you can take some of it off. I’ve never milled one down to the block so I can’t say you can take it all off.
IIRC you need to take somewhere around .200-.250 off to get the pump to clear. I take just enough off to get the pump in there.
IIRC you need to take somewhere around .200-.250 off to get the pump to clear. I take just enough off to get the pump in there.
donald smith
Member
Thanks for the input ive never had to doit but some hp pumps will not clear
donald smith
Member
On most early la engines on the pass side of the block were fuelpump diaphram sets is a casting stickingout about 1inch an a half about like the end of a hot dog weinnie and on some hp aftermarkit pumps wont clear it
donald smith
Member
If you fool with enough ofem you sooner or later will when you use a pump other than stock pump
mopardude318
Well-Known Member
I’d like to see pictures just to see what’s going on. 
Rat Bastid
Dunamis Metron
My bad. As the OP said, on some blocks there is a nub on the front of the block that’s real close to the mechanical fuel pump.
Sadly, I’ve never kept notes on that nub (I should have) to get an idea if the size of the nub changed over the years or some other change occurred.
It doesn’t happen often but some blocks, for whatever reason have the nub height/location or both in a position where the bigger, bolt together mechanical fuel pumps hit that nub.
I’m not close enough to the shop to get a picture, but I suspect (I’m guessing actually) that that nub is a riser for getting the air out of the mold when the block is being cast.
Ive never machined one off completely to see if there is a passage into the nub or not.
If I ever get ahold of a junk block I’ll grind it all the way off to see if it’s an issue.
I know some guys who need block weight at the minimum remove all kinds of extra casting features without issue. Like the engine mounts and such. I have to think that over the long run of the LA engine someone has taken that nub all the way off.
The result of that Ive never seen.
Here is a pic I just took, the boss is pretty close even on a stock pump.
donald smith
Member
i just looked at another 340 block i have and you can stick your finger all the way in and around that area behind the snub through the freezeplug hole its flat all the way so id say you could remove this snub all the way to the block with no issues
donald smith
Member
mabi this will help other mopar lovers in the future thanks again for your interest when you want to go fast and hard in a mopar and b first alot of times you have to do what the manufacture didnt..... mopars 4 ever
Heres our 67 273. Machined flat, approx 3/8" away?
Rat Bastid
Dunamis Metron
Yep, thats the offending nub right there.
My 1971 340 (cast date 1970) has the nub as well. My Holley mechanical pump hits it.
Your wife told me that you had an offending nub.
Rat Bastid
Dunamis Metron
Oh yeah, she will swear to that in court. Of course, she got sick yesterday so that’s my fault don’t you know lol.
So, I’m pouring DayQuil down her as fast as the law allows. I get a dirty look because it tastes bad. And yes, since she’s sick that’s my fault too because I didnt get theraflu, which no one around here has for some reason lol.
So yeah, the better half has way more grievances with me then the aggravating, offending nub!!!
LMAO. Just know I share your malady. lol
Not a 340 but a 67 273.
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