Cap walk problems

DGS wrote:Let it walk, not a huge deal, caps won't break. JMExperience.

No, they will break and do. I think you will hear from others on hear that will say the same thing. But as far as bearing damage by cap walk, as long as you have enough oil clearance to keep the bearing off the crank when it moves into the bolt and stops, your right, it's not a huge deal.

And I have seen them still running with the cap broken, and the bearings looked fine. But I still say look into main straps or a 4 bolt conversion if over 800 hp, if you want to feel warm and fuzzy.

IDT-572 wrote:

Lem Evans wrote:Compared to Nicplaus Copernius.....Einstein was an idiot .

Wasn't Copernicus's grand father on his mother's side a Williams?

Nikolas Capernicus, 1473-1543. polish scientist who discovered the heliocentric universe. the Church was scandalized because it was against their policy that the universe was geocentric, from the calculations of Ptolemy. I think he may have been a Williams.

61coon wrote:

IDT-572 wrote:

Lem Evans wrote:Compared to Nicplaus Copernius.....Einstein was an idiot .

Wasn't Copernicus's grand father on his mother's side a Williams?

Nikolas Capernicus, 1473-1543. polish scientist who discovered the heliocentric universe. the Church was scandalized because it was against their policy that the universe was geocentric, from the calculations of Ptolemy. I think he may have been a Williams.

Mean SOB I thought he was a WILLAMS

61coon wrote:

IDT-572 wrote:

Lem Evans wrote:Compared to Nicplaus Copernius.....Einstein was an idiot .

Wasn't Copernicus's grand father on his mother's side a Williams?

Nikolas Capernicus, 1473-1543. polish scientist who discovered the heliocentric universe. the Church was scandalized because it was against their policy that the universe was geocentric, from the calculations of Ptolemy. I think he may have been a Williams.

I though he was the guy who invented Kolbasa!!!!

Guy's I have a regarding the cap Straps. When you install the cap straps,Does the engine need to be line bored ? And does the straps absolutely need to be made from TOOLED STEEL?

bbf-falcon wrote:Guy's I have a regarding the cap Straps. When you install the cap straps,Does the engine need to be line bored ? And does the straps absolutely need to be made from TOOLED STEEL?

Yes you should line hone the mains ( not necessary to line bore) when using straps and IMO I'd use a high grade of steel, it's not that expensive as you only need 5 short pieces.

DGS wrote:Let it walk, not a huge deal, caps won't break. JMExperience.

Maybe they won't break if YOU are not making any serious power.

Charlie

dfree383 wrote:

bbf-falcon wrote:Guy's I have a regarding the cap Straps. When you install the cap straps,Does the engine need to be line bored ? And does the straps absolutely need to be made from TOOLED STEEL?

Yes you should line hone the mains ( not necessary to line bore) when using straps and IMO I'd use a high grade of steel, it's not that expensive as you only need 5 short pieces.

Thanks Dave

I wonder would you still get cap walk if the 2 bolts were splayed instead of straight up and down?
I know it can't be done, but it would be interesting to find out. Cheers Colin

DGS wrote:Let it walk, not a huge deal, caps won't break. JMExperience.

hi welcome, thanks for imput but u must drive a geo metro ,or u would all ready know that the caps will break
and not huge deal if they cap walk, well i am hope that u never get to tune or build any race motor for any body that i know because u dont know s##t.
you need to read up on a bbf before the wolfs get u at the bar!!!!!!!!

p.s. if the evean's tell you it will happen you can take it to the bank!!!!!!!!!!
p.p.s have a nice day!!!!!!!!!!!!!!!!
logan

Guys,

I appreciate any and all opinions on this. Everybody has had different experiences, and the good thing about a site like this is that all opinions are generally valid and have merit.

The cap strapping sounds interesting to me. I presume the caps are milled flat on top and bar stock is placed over the cap between the bolts?

As far as line honing after adding the straps, just torque them to spec and check the housing bore. I have done them on 2300 ohv ford 4 cyl and 302's and not had to hone them.

Greg , yes mill the top of the cap flat, As far as the material , I just made the caps thick enough that cold roll was fine.

Also Hienergy, splayed main bolts I feel would probably stop it as it would pull the sides of the caps tight into the register. I think the reason BBC 's don't have cap walk issues as bad as the BBF with their 2 bolt caps is it has a much larger foot print ( more cap outside the bolt pattern )


JMHO

What thickness do you recommend?

min. .625

The force of the crank pushing staight down and the bolts clamping on an inclined angle, less chance of the bolt streching. That's why the splayed 4 bolt conversion is better than 4 bolt SCJ cap to stop cap walk.
Cheers Colin.

Greg_P wrote:Guys,

I appreciate any and all opinions on this. Everybody has had different experiences, and the good thing about a site like this is that all opinions are generally valid and have merit.

The cap strapping sounds interesting to me. I presume the caps are milled flat on top and bar stock is placed over the cap between the bolts?

Greg,
Here is some pictures of the straps and how the caps are machined.

https://www.429-460.com/stuff-for-sale-f1/wtb-main-stud-kit-2-bolt-dove-a-t2256.htm#24007

Awesome, thanks for the pics...now I'm clear on what the straps do and how they fit.

Too bad I didn't get educated till after they sold, though!

Greg

Thanks for the cap strap edumacashun...


Greg,

I've got a block that has worse cap walk than that. Everyone and their grandma looked at it at the Bash and all agreed to just hit the caps and saddles on a honing stone to knock the high spots, throw some anti-sieze in there and torque them down extra snug with studs and I'll be fine... That's what I'm going to do...


My thought is it's not walking anymore, but probably did when the tune was off. OR it might be walking on the initial hit of the bottle...

billandlori wrote:

richter69 wrote:Put the good crank in it, a little anti sieze between the caps and block, start saving for an aftermarket IMO.

Jon, does the anti sieze just allow the caps to do what they are gonna do with out the metal transfer?

Bill

Anyone??

Put a good set of aluminum rods in it, ARP studs torqued to about 105-110 w/molly, have it line honed, and STOP already with the lean tunes!

Bret

I asked that question today, and thats what I was told, they will still walk, just won't gall.

342g wrote:I asked that question today, and thats what I was told, they will still walk, just won't gall.

10-4 Thanks!!

Bill

I had this same problem. at 1016rwhp its time for an A block before I drive through my own oil again on the big end.

interesting... subcribing

i am a firm beliver in the lean tune up you just have to pull some timing BBF dont like that much timing anyway lean it out and pull some timing