girdle on 460

anybody running girdles on the bbf, which ones do you like DSS? Canton?

This should be a good one. Most people here don't believe in them but there are a few that say they "should" help. The fact that there are plenty BBF's making over 900 hspr in a stock block seem to negate it's need. This topic is almost as controversial as Pro comp.

The one thing that makes me wonder is that you never hear from people like Mark (Probe) when this topic comes up. Do they have some data to support the need or do they just make them because people think they need them?

i ran a girdle on my 521 and ... a canton girdle...... and when we torn down the motor there was still a ton of cap walk ...... and that was only with a 100 shot ......

i would spend the money on a 4 bolt conversion ..... or a SVO block

just my .02

this could be another good sticky for the newbs if we can keep the remarks educational

here are some pics of the tear down ...this was with 90-100 passes half are with the spray ....... did the girdle help ??? i dont know











you can definetly see cap walk !!!!!

Nick, what spot exactly shows the cap walk? I keep hearing about it and I'm not sure what the evidence is. I can see where the bearing insert end looks kinda mushed around...is that it?

Bill

Im curious as well.

Is the crank moving side to side (like left to right) or up and down (towards intake then towards oil pan) or is it moving front to back (towards trans then towards radiator)...combination of all 3?


Ive got the girdle windage tray and oil pan shown on Nicks motor. It may not help but Im pretty sure it doesnt hurt. You hear all types of stories and most say dont waste your money on a girdle. The strange thing is you hear one story about a stock block holding 900hp without cap walk then in the next post you hear a story of a 700hp motor with tons of it. Is it something seen more often with nitrous vs NA? Aluminum rods vs steel? 6000rpm vs 7000rpm+? Is it just one of those X factor things?

Id never say the girdle is a replacement for a 4 bolt stock block and certainly not for a aftermarket block but I guess I built what I could afford at the time.

I'm thinking "cap walk" is the main bearing cap moving front to back. They can't go side to side because of the registers machined into the block.

Bill

Boils down to this, if you already have the girdle and are not using it to try and cure the cap walk bolt it on.

If you dont have one, dont go out and buy one.

If your wanting to fix the cap walk issue get some 4 bolt caps.

If anything the girdle will make a nice handle to pick up the pieces by...................

What makes the caps walk is the crank putting stress on the lower main caps and it is like a bridge moving in the middle and the Main girdles do not stop or prevent that. The Girdles are built wrong for helping any of that... the Main caps should be milled flat so the strap is flat on the cap not with bushings holding it above the cap....Now if you mill the caps flat with the top bolt/stud holes and just put a strap across the bolts/stud holes it will do more to keep the mains from Fretting than any girdle ever will...
So in essence the girdle is just a way to relieve your pockets of unwanted CASH and place it in their Pockets........ IT DOES NOTHING TO HELP CAP WALK/OR FRETTING AT ALL......


Randy

The movement of the cap is as it is being "pinched" from the sides is essence. What actually is at work here is that crank is pushing down on the center of the cap, and the main bolts are holding the cap to the block. It is a scrubbing that occurs as these forces are applied. 4 bolt caps are basically useless unless they are of a spayed design. The outer 2 splayed bolts keep the cap from being pulled inward at the sides. As far as a girdle, it is no replacement for a good splayed 4 bolt design, but if set up properly can help to alleviate some cap walk, by supplying some rigidity to the bottom of the cap. It does not make the cap or block stronger, but reapplies some of the forces. If this girdle only ties to the main bolts it is less than effectice, but if tied to the pan rail it can help. In all honesty, save the money from the girdle and get a good set of splayed 4 bolt caps or a performance block which will already have them.

Cap walk is not front to rear movement, it's the cap bolt streching / caps bowing under load. Can also result from detonation to, not just high hp. The typical girdles are ineffective as the do not touch the cap where it needs support ( middle), cap straps are more effective than the cheap girdles on the market.

Put the money towards 4 bolt caps or a better block. Strait 4 bolt caps are an improvement and not useless, but the spayed stuff is better.

billandlori wrote:I'm thinking "cap walk" is the main bearing cap moving front to back. They can't go side to side because of the registers machined into the block.

Bill

The registers will not keep the two bolt caps from lifting/bending . The pistons are trying to drive the crank into the oil pan...not front to rear .

Lem Evans wrote:

billandlori wrote:I'm thinking "cap walk" is the main bearing cap moving front to back. They can't go side to side because of the registers machined into the block.

Bill

The registers will not keep the two bolt caps from lifting/bending . The pistons are trying to drive the crank into the oil pan...not front to rear .

that is what my machinist told me trying to push the cranks out the bottom of the oil pan some type of support is better than nothing and when you tie them together it has to take some of the punishment vibration and harmonics, This gives some good examples

http://www.dssracing.com/SearchResults.asp?Cat=6

A four bolt savings account is best . Starting with the $s one would have spent on the girdle deal...i.m.o.

Lots of good arguments for and against them, but since I have been using one for close to 6 years on my blown 473 and last time we had the pan off the bottom end checked out with no cap walk, and keep in mind unlike regular motors I have a 3" wide belt tugging on the crank snout. I agree a 4 bolt splayed block is better or buy an a460 block from Lem, but the girdle doesnot seem to hurt, and in fact on the new 545 I'm building I'm going to splayed caps and a girdle on top of them. Hall bros uses this same setup on a pro car and runs 8 to 9 sec quarters with reliability. Bottom line if you want to make power above 750 and race regularly I would buy an aftermarket block. If its a bracket racer/street car and your budget won't allow a $2100 block a girdle is not going to hurt, at worst your throwing away a couple hundred bucks, I can only tell you my motor has held up to the test.

Ive used both. Definetly splayed 4 bolt is better. Cheers Colin

Lem Evans wrote:A four bolt savings account is best . Starting with the $s one would have spent on the girdle deal...i.m.o.

Lem, what kind of cost is a guy looking at for a 4-bolt conversion these days?

Greg

Greg_P wrote:

Lem Evans wrote:A four bolt savings account is best . Starting with the $s one would have spent on the girdle deal...i.m.o.

Lem, what kind of cost is a guy looking at for a 4-bolt conversion these days?

Greg

I.U.D. 572 Blake.... may know .

blown473 wrote:Lots of good arguments for and against them, but since I have been using one for close to 6 years on my blown 473 and last time we had the pan off the bottom end checked out with no cap walk, and keep in mind unlike regular motors I have a 3" wide belt tugging on the crank snout. I agree a 4 bolt splayed block is better or buy an a460 block from Lem, but the girdle doesnot seem to hurt, and in fact on the new 545 I'm building I'm going to splayed caps and a girdle on top of them. Hall bros uses this same setup on a pro car and runs 8 to 9 sec quarters with reliability. Bottom line if you want to make power above 750 and race regularly I would buy an aftermarket block. If its a bracket racer/street car and your budget won't allow a $2100 block a girdle is not going to hurt, at worst your throwing away a couple hundred bucks, I can only tell you my motor has held up to the test.

Not trying to be smart here....but it does make one wonder why four bolt blocks are produced if the two bolt units are good enough .

Years ago, the first main girdles for 429/460 engines had FLAT spans between the main cap bolts and the caps NEEDED to be machined flat on top to get them to fit correctly. The girdles got a good reputation for strengthening the caps while tying them somewhat together.

Manufacturers weren't SELLING enough of them, (mainly because it took machining to install them), so, they made them easier to install without the need to modify the caps which also made them a lot less effective. Do these new designs help...? Maybe a little but, if they give people "piece of mind" and it's their money ... oh well.

X-2

So if we were to own and use one of the older ones it would probably help the two bolt block? I bought one around 5-6 years ago and had to have the caps machined for it to fit properly as well as having it line bored with all this installed. I take the engine apart every year and havent noticed capwalk where as before the girdle it was showing a little, I'll check it again here in a few weeks.

jasonf wrote:The one thing that makes me wonder is that you never hear from people like Mark (Probe) when this topic comes up. Do they have some data to support the need or do they just make them because people think they need them?

Sure you do. I don't make one for the 460. If someone insists, I sell them a Blue Thunder.

Other than a 302, where it's a safety item, and a 351W...where it can help with cap walk, I don't see the point.

Like has been said, when you get to the point in (HP)time that you are past the limit for a 2 bolt block,IMO it's time for a RACE block. My block is a oem A block w/4 bolt billet caps, but their NOT splayed. They have DOWEL pins inserted in the block/caps.I think Lem will be selling a block this winter.

Mark O'Neal wrote:


Sure you do. I don't make one for the 460. If someone insists, I sell them a Blue Thunder.

Other than a 302, where it's a safety item, and a 351W...where it can help with cap walk, I don't see the point.

Thank you for the correction Mark. I thought you had a 460 girdle. My bad. I think your opinion speaks volume when a manufacturer doesn't think they are necessary.