Lifter bore spacing..

[RustyRatRod]

Does anybody know lifter bore center to center spacing for small blocks and big blocks? Thank you drive through.

 

[RAT ROD AL]

 

[RAMM]

Does anybody know lifter bore center to center spacing for small blocks and big blocks? Thank you drive through.

Best way would be to grab your favourite pair of 6" calipers and measure wall to wall of a pair and add lifter diameter. It should be a nominal number but it may be something weird from whatever the engineer decided on way back then. For example if I came up with 2.123" I would guess that it was really 2.125" which is a nominal number. It may not though--might be something arbitrary like 2.077" . J.Rob

 

[RustyRatRod]

Best way would be to grab your favourite pair of 6" calipers and measure wall to wall of a pair and add lifter diameter. It should be a nominal number but it may be something weird from whatever the engineer decided on way back then. For example if I came up with 2.123" I would guess that it was really 2.125" which is a nominal number. It may not though--might be something arbitrary like 2.077" . J.Rob

I would do just that, but all I have are slant six engines. That's the whole point of asking here.

 

[gzig5]

1.760" +/- .005"
I have a cleaned 340 block in the basement. I plunked pair of Comp solid lifters in the holes and measured between them with a caliper. On the outside I came up with 1.758 and on the inside 1.765. I used .904 for the lifter diameter. There is some slop in this method and I didn't take a lot of time to do it, but if the designing engineer wasn't a dick, the target number is probably 1.760" plus some tolerance.

Edit to add.....This was distance between intake and exhaust on same cylinder.

 

[RustyRatRod]

1.760" +/- .005"
I have a cleaned 340 block in the basement. I plunked pair of Comp solid lifters in the holes and measured between them with a caliper. On the outside I came up with 1.758 and on the inside 1.765. I used .904 for the lifter diameter. There is some slop in this method and I didn't take a lot of time to do it, but if the designing engineer wasn't a dick, the target number is probably 1.760" plus some tolerance.

Edit to add.....This was distance between intake and exhaust on same cylinder.

Thank you! This is a start.

 

[33IMP]

I havent measured anything, but maybe..... 1.750?
Gimme a few, i can get the big block.
Edit: got a bigblock with the intake off, but no pairs of lifters high enough to get an accurate number, but.... quick and very dirty measurement says around 1.750.
Im sure gzig5 is more accurate than me!
2nd edit: sorry, just noticed this is in the small block thread. Oh well....

 

[moper]

Measuring inside to inside needs to have (2) “half lifter diameters” ( or .904) added to get the center to center distance. Still doesn’t account totally for slop. So 1.7625+.904=2.6665 give or take...

 

[33IMP]

Measuring inside to inside needs to have (2) “half lifter diameters” ( or .904) added to get the center to center distance. Still doesn’t account totally for slop. So 1.7625+.904=2.6665 give or take...

I think he did it right. He just compared outside to outside minus lifter dia, vs inside to inside, plus lifter diameter.
My big block is around 1 3/4, i dont think a small block spread is almost an inch greater.

 

[moper]

Six of one...
regardless of how it’s measured the inclusions have to be all there for center to center.
I just measured a 383. Not perfect accurate but 1.897 center to center.

 

[RustyRatRod]

Thanks yall. This gets me close enough to make a decision.

 

[RustyRatRod]

Six of one...
regardless of how it’s measured the inclusions have to be all there for center to center.
I just measured a 383. Not perfect accurate but 1.897 center to center.

The slant six is really close to 2" so I believe the big block lifters will be the right choice. Thanks man.

 

[dirty white boy]

The slant six is really close to 2" so I believe the big block lifters will be the right choice. Thanks man.

BB roller? lifter?????

 

[moper]

Not that I’ve given it any thought... but the factory hydro lifters have those flats cut for the dog bones. There might be a lot more slop in that arrangement if something could be made to work, than a tie bar that’s a hair wide. If you want solids just shim the plungers.
Just thinking about what you seem to be angling for.

 

[RustyRatRod]

BB roller? lifter?????

Yeah.

 

[dirty white boy]

Yeah.

cant wait to see this engine run!!

 

[RustyRatRod]

cant wait to see this engine run!!

This one's gonna be a bit. It's the one I'm putting the closed chamber head on. Ported the snot out of with 318 valves.