girdle kit

[matty wardle]

hi i was just wondering why you need to line hone your mains when you install studs and you dont have to when using bolts,i am putting a girdle on the bottom of my 451,overkill i know ,but the whole kit was only $335 from mancini and the studs alone where $100,so i went with the kit?

 

[smlveightis]

IMO, all engines should be line honed when being rebuilt. Just standard operating procedure, as far as i'm concerned. I'm sure others will chime in with more technicial definitions regarding this.

 

[moper]

The reason for the align honing after you change fasteners is because the main bore is machined with the original fasteners. The final bore shape is set when that particular fastener is preloading the block and cap. When you change the bolt, use something stronger, or go to a stud, you change the amount the bore distorts, and thus change the shape of the bearing bore. When going bolt to bolt, it's not much of a change simply because the material of the fastener makes little difference in comparison to the type of fastener. When you change to a stud, it preloads much differently and can distort things so much that the bearing clearance is affected.
If you are at all familiar with the horrid quality of the factory machining, and can appreciate a true performance engine, you'll have every block align honed regardless of new bolts or not. I have yet to find a factory one that did not improve at all by haing it done, and a good shop's equipment needs the main bore to be perfect as it indexes off it.

 

[Mad Dart]

I will line hone the mains and the cam journals on every engine I do from now on. I had Brian at IMM line hone the cam journals on my last block. It is the easiest engine to rotate so far that I have built to date. It made a tremendous difference compared to the other engines I have built.

 

[smlveightis]

Thanks for the info moper!!

 

[matty wardle]

thanks for the info on this guys,i now understand it much better,i am going to get my line honed anyway on the mains cause i,m going from factory bolts to studs,but i was really hoping to get away with leaving the cam bearings in there and just fully cleaning the block in a none caustic solution,from what i,ve read,not doing the cam bearings isn,t that crucial and they look to be in good nick,what failures can happen if you dont do the cam bearings?

 

[1970Duster]

Before you line hone the block, I'd order up some heavy duty billet main caps for ultimate bottom end strength (this way you only have to line hone it once).

 

[moper]

You can't leave the cam bearings in place. The machining causes chips and tiny bits of abrasive iron and honing stone to be stuck in the oil feed passages. You have to remove the bearings to clean the passages... This is the same deal is when a cam goes bad or anything else that gets crap into the oil passages. The only wany to clean is to get the block bare, and only a clean block makes a long lived engine.

 

[7172 duster]

you can't leave the cam bearings in place. The machining causes chips and tiny bits of abrasive iron and honing stone to be stuck in the oil feed passages. You have to remove the bearings to clean the passages... This is the same deal is when a cam goes bad or anything else that gets crap into the oil passages. The only wany to clean is to get the block bare, and only a clean block makes a long lived engine.

x2