All Small Six Back in the Saddle

[cr_bobcat]

No. Haven't been out to work on anything in a week or so. We're getting ready to host some of the out-laws this week for spring break. I will try to sneak out to the garage and at least try to make cylinder #1 work. Anything beyond that will be the cherry on top.

 

[pmuller9]

How did hosting the Outlaws over spring break go?

 

[cr_bobcat]

Ok. Apologies for the delay. I will have some time Sunday for sure to get into the 200 and do a fit check. I'm crossing my fingers but I'm optimistically hopeful.

Out of curiosity, does anyone have a notional idea of how much meat is necessary around the edge of the deck to maintain gasket integrity? I don't think I'll have any issues with it, but I thought I would ask. My thought is that worst case I would have to copper coat just to make sure that any loss of material there wouldn't result in a potential for a blown gasket. TBH though, It's so far away from anything that it shouldn't be a concern and I'm not making it any narrower than any of the other spots.

 

[pmuller9]

Out of curiosity, does anyone have a notional idea of how much meat is necessary around the edge of the deck to maintain gasket integrity? I don't think I'll have any issues with it, but I thought I would ask. My thought is that worst case I would have to copper coat just to make sure that any loss of material there wouldn't result in a potential for a blown gasket. TBH though, It's so far away from anything that it shouldn't be a concern and I'm not making it any narrower than any of the other spots.

The most pressure is between cylinders and as long as you have more surface area around the rest of the circumference of the cylinder it should be OK.

 

[Invectivus]

Does anyone know how much lobe lift we're looking at for this? David posted that the stock 200 cam had a .348" lobe lift, and a later 250 cam had a .368" lobe lift. Bubba at one time said he couldn't find an aftermarket cam with higher than .330".

The Clay Smith cams seem to max at .456" based on a 1.6 ratio, so .285" at the lifter. These are flat tappet cams, would a roller be taller, ot just more aggressive opening and closing?

 

[awasson]

Does anyone know how much lobe lift we're looking at for this? David posted that the stock 200 cam had a .348" lobe lift, and a later 250 cam had a .368" lobe lift. Bubba at one time said he couldn't find an aftermarket cam with higher than .330".

The Clay Smith cams seem to max at .456" based on a 1.6 ratio, so .285" at the lifter. These are flat tappet cams, would a roller be taller, ot just more aggressive opening and closing?

Those numbers are the valve lift as interpreted by the 1.6 ratio rockers. I measured lift off the lifter when I did my Clay Smith H-6474-0-B camshaft when I degree'd it. I'm surprised I kept this note but someone asked me to check it when I was doing the install so I kept it in my notes. It lines up with what Bubba has said:

Intake lift: 0.3075”
Exhaust lift: 0.290”

EDIT: I would think a roller would be twice as tall as a flat tappet lifter.

 

[Invectivus]

Yeah, in hindsight I should have searched for lobe lift differences in the 302. They can apparently get up to .500” lift.

 

[Frank]

Yeah, in hindsight I should have searched for lobe lift differences in the 302. They can apparently get up to .500” lift.

.348 lobe lift = .522" valve lift w/ 1.5 rockers, .557" valve lift with 1.6 rockers. Way beyond a stock cam.

 

[awasson]

.348 lobe lift = .522" valve lift w/ 1.5 rockers, .557" valve lift with 1.6 rockers. Way beyond a stock cam.

I wonder if David was talking about valve lift on a stock camshaft as interpreted via a stock 1.5 ratio rocker rather than lobe lift.

I've read that the lobe lift on stock cams was around 0.24 - 0.26 so if you multiply that by 1.5 you're going to be in the range of .368

 

[Frank]

I wonder if David was talking about valve lift on a stock camshaft as interpreted via a stock 1.5 ratio rocker rather than lobe lift.

I've read that the lobe lift on stock cams was around 0.24 - 0.26 so if you multiply that by 1.5 you're going to be in the range of .368

Agreed. The whole confusion hinges on the terms lobe vs valve. The numbers are total lift after the rocker multiplication. Easy mistake to make.

 

[pmuller9]

Nice way to side track this section of the thread.
Thanks guys.
The focus was on whether or not a roller lifter can be installed in a 200 block.