Cap walk problems

When you start creating horsepower in your blocks regardless if they are a 2 bolt or 4 bolt block's the only thing holding your main caps or splayed caps in place is the register of the block and your hardware. When your motor is running, especially under highly loaded conditions, the crankshaft is being twisted and is trying to move the main caps.

In other word the crankshaft is trying to kick itself out of the block. With enough horsepower the crankshaft will move the caps inward causing "cap chatter" . Once this occurs your main caps are no longer register into your block and your caps have become egg shaped. A stap or a girdle is not going to stop this! If you are making enough power to lift the cap then your strap and girdle are going to lift with the cap. The only way to stop cap walk is to lock the cap into the block so that the cap can not move inward.

http://strokerkits.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=119&category_id=16&option=com_virtuemart&Itemid=1

I found these guys making these caps at the PRI show. These Splayed caps are different then anybody elses. They actually stop chatter. We install two sets on two different 460's and are making well over 1000 hp on these blocks with no cap chatter.

http://strokerkits.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=111&category_id=19&option=com_virtuemart&Itemid=1

They make a nice cap thats for sure, but at $400 a set and the machining to install them , about another $300+ or to buy their block at $1500 , why wouldn't you just be smart and buy an A460 block? Look at the caps on the A460 block in Lem's ad. Theres flat no comparison. Especially in the crown of the cap where the bending pressure builds up. The A460 is huge there. The point of discussion has been cost for the budget racer. A factory 2 bolt block with inexpensive "cat " caps installed will probably handle up to 80% of the load the $400. cap will. And the caps AND installation will cost about just the price of the highend caps alone. You can put a Cadillac hood emblem on a Chevy, and its still a Chevy. We will never settle the girdle issue here, so if you believe they are ineffective don't buy one, but many reputable companies make them (Blue Thunder, DSS, Etc) and stand behind their product. My personal experience and I will qualify this , has been positive. I'm running blown, but I'm using stock 460 stroke, which I think is less strain on the caps, and most blower shops will tell you the blower 3" belt dampens out the crank harmonics. So much so in fact you don't have to run a harmonic balancer on a blown motor if the initial machine shop balance is done without one. This is the way my Hampton blower was set up from day one. I have a D1 Block (2 bolt) with a 5/8 steel girdle on it, and for now 7 years of use and no cap walk. This is behind a stick, so it gets launched hard. I'm working on a new motor, and it will be 4 bolt and with a girdle on top of that. I can't see the harm in trussing up the bottom end. For the people with "track " only cars that never see street time you should spend the money for a good block, I just can't see having $1500. into a factory block.

no but you will have a nifty holder to pick up all the junk with when it lets go....


Randy

and to think. For that kind of money no screw in freeze plugs.
http://strokerkits.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=119&category_id=16&option=com_virtuemart&Itemid=1

ace

That and old joke, and probably shows a weakness somewhere else in your motor.

Screw in freeze plugs? Do you actually have any idea why blocks even have freeze plugs? Does aftermarket blocks come with screw in freeze plugs? I’m just saying that this would be a good block for a guy making around 1000 plus hp. I’m not saying it’s the block for a twin turbo 1600hp motor. But why spend around $2200.00 for a A460 block then need to spend in additional $400.00 - $500.00 to have it machined. That’s around $2700.00 dollars when you can get a full complete 460 that will hold 1200 plus hp for $1500.00 that’s a savings of $1200.00 dollars. Since we are dropping names ( John Kaase ) uses these blocks in his Kaase P-51 520 c.i. Engine. I was just showing another option for guys that are building decent power but not enough to have to justify buying an aftermarket block. Most guys don’t realize when you buy an aftermarket block you still have to have these machined. Have a good week end guys!

blown473 wrote:That and old joke, and probably shows a weakness somewhere else in your motor.

??

sunvalley54 wrote:Screw in freeze plugs? Do you actually have any idea why blocks even have freeze plugs? Does aftermarket blocks come with screw in freeze plugs? I’m just saying that this would be a good block for a guy making around 1000 plus hp. I’m not saying it’s the block for a twin turbo 1600hp motor. But why spend around $2200.00 for a A460 block then need to spend in additional $400.00 - $500.00 to have it machined. That’s around $2700.00 dollars when you can get a full complete 460 that will hold 1200 plus hp for $1500.00 that’s a savings of $1200.00 dollars. Since we are dropping names ( John Kaase ) uses these blocks in his Kaase P-51 520 c.i. Engine. I was just showing another option for guys that are building decent power but not enough to have to justify buying an aftermarket block. Most guys don’t realize when you buy an aftermarket block you still have to have these machined. Have a good week end guys!

Most guys are to cheap too...........They will spend $5000 for a set of Killer heads and want to put them on a stock block with a cast rotating assembly...... The Irony of it all.

blown473 wrote: The point of discussion has been cost for the budget racer. A factory 2 bolt block with inexpensive "cat " caps installed will probably handle up to 80% of the load the $400. cap will. And the caps AND installation will cost about just the price of the high end ($400) caps alone.

Agreed. The Cat caps will hold as much power as the $400,000,000 4-bolt caps, in effect, because the passenger car block will disintegrate under high enough horsepower conditions long before ANY billet steel cap on the market will. Even the 4-bolt Milodon iron caps will lost longer the the stock block. And when all is said and done $400 is the high side of 4-bolting the block, price of caps included.

Paul

Thanks Paul.

My 557 has the Cat caps on it . and has had the shit ran out of it, and to many dyno flogs to count. it still has the same oil pressure it had when first started. I will show some pictures soon, as the engine is coming out of the car and apart in the next week or so.

850+ hp 760 torque

With the problem of cap walk, I'm still suspicious that the cranks we see flexing the caps and breaking at the rod journals are all Chevy diameter. Most guys running factory cast 460 cranks are not having problems . Less stroke has to be a factor and greater material in the rod journals has got to effect the crank harmonics. The cast stroker cranks had a history of failures at the rod journals. The N/A motor guys really push the rpms to get peak power, most of us blower guys don't need to see past 6000. We can just speed up the blower faster than the crank. Its an interesting subject to say the least. I'm going to try the FRPP M-6303-A514 cast crank with the Ford rod journal size in my new motor, with my eagle h-beam 6.605 rods, cat caps and main girdle on the caps , we will see if it holds up like my current motor has. If it does not then everyone can give me a "I told you so"

I told you so, for your application you should have a steel crank in the first place......99% of the problems with the cast cranks is the flex when you get the bigger strokes so you need a steel one...




Randy

I have not seen a forged crank with the 2.5 Ford rod journal yet, but it might exist. The vast majority of blower motors you see in street/strip cars out here are cast crank. Especially the blown AMC's, Buicks, Cads, that don't have inexpensive forged units available. Not everyone runs their cars hard but alot do. I run my factory 460 crank hard, and so far , so good. The longer stroke might change all that, might not. Theres no doubt that you guys run much harder on your track only cars, compared to cruising the blvd. I see the FRPP crank holding up better than a comparable scat or eagle crank just on the much larger amount of metal in the rod journal itself. I also think blower motors have an advantage in dampening out the crank harmonics. If I can afford to give away as many parts as I have on the 2 forums, then its obvious I can afford to buy whatever parts I want. I choose to do this new motor this way because since 1975 all the Fords I have had and raced were cast crank 289,302,351w, 351c, 390, 410, 430MEL, 460. The only exception is my 2004 lightining which is factory forged. In all these years I have had 1 motor blow, an FE kicked a factory rod. I'm sure machining and balance are a major part of my luck, I've been using the same machinist since 1989, and haven't blown a motor since. Sadly our local drag strip is being forced to close in 2 years, so our track days are numbered as well, so my motor will be doing more cruising than racing. Can't keep any tracks open in CA.

IDT-572 wrote:Thanks Paul.

My 557 has the Cat caps on it . and has had the shit ran out of it, and to many dyno flogs to count. it still has the same oil pressure it had when first started. I will show some pictures soon, as the engine is coming out of the car and apart in the next week or so.

850+ hp 760 torque

Just tore down charlie's and my 2009 466 emc entry and it is showing light cap walk, nothing I'd get worried about but they are moving on an 11.5:1 466 ragged edge tune pump gas motor at mid 700 hp.

One thing no one has caught or mentioned is that just like any other part in the engine, theres a huge difference in quality out there. Theres alot of import girdles on the market that so thin and wimpy they don't have the strength to do the job. A 1/4 inch plate probably isn't going to help. The best ones I've seen are the steel 5/8 plates with real ARP fastners, not stuff you can tell is junk just by the fuzzy finish on the hardware. The better stuff also isn't just a flat plate, but has some engineering in it for stroker clearance and oil pump clearance. You have to wonder if you put it on the motor and it hits everything, and the pan won't go on, do you want to buy parts from that engineer? A small amount of fitting is normal, but a thin universal flat plate is not what you want to be running.

for a fact the way the are connected to the main caps it don't make a FREAKIN Hill of beans which one you use, they DO NOT WORK.........The Main cap bows in the middle out and the Stupid Girdle does not even touch it there to stop anything..... The only thing they are good for is removing cash from your Wallet......I don't care if the girdle was 10 inches thick the washers let the cap bow.....



Randy

I can see why "CHILLY" banned you...

blown473 wrote:I can see why "CHILLY" banned you...

I would rather have Randy's (or anyone's) raw/honest/uncensored opinion on most any subject vs getting the play nice "agree to disagree" bull siht. Or worse no usable feedback at all cuz of yes men having no opinions & agreeing with anything said.

Political correctness be damned.

So from what I have gathered from all the threads is you need to change ALL the caps to stop them from bending in the middle. Does someone make a kit with the 3 center caps 4 bolt then a 1&5 cap that is still 2 bolt but better quality steel?

jason most of the torsional twist is in the center ther may be slight walk on the front and slight on the rear cuz it is so wide, but the middle 3 are the most inherant to these problems...


Blown you are using a cast crank on your engine thats ok, it is your fault when it Crashes, no one to blame but you, if you want to be cheap Hey Man go for it Personally I would have a forged crank in it. and as for the 2.5 rods vs the 2.20 I will take the 2.20 anyday when I can.... and beside you wanting to put a 4.3 ford cast crank in go for it but you will have to spend some bucks for pistons cuz they have been obsoleted (that means they are not shelf items any more they are custom orders...) as for Chilly Banning me thats cuz he stays in a Drunken Stuper....

Have a nice day


Randy

DILLIGASDAVE wrote:

blown473 wrote:I can see why "CHILLY" banned you...

I would rather have Randy's (or anyone's) raw/honest/uncensored opinion on most any subject vs getting the play nice "agree to disagree" bull siht. Or worse no usable feedback at all cuz of yes men having no opinions & agreeing with anything said.

Political correctness be damned.

x2 rock on Coug!!! Sometimes the truth hurts their feelings........

you guys still arguing about girdles?????

got one of them nice 5/8" thick girdle will clear 4.500 stroke bolt holes for screen. sell for $25 . no studs, used them. this is a blue tunder girdle, did it stop cap walk- F no but i can use the $25

DanH wrote:got one of them nice 5/8" thick girdle will clear 4.500 stroke bolt holes for screen. sell for $25 . no studs, used them. this is a blue tunder girdle, did it stop cap walk- F no but i can use the $25

Another satisfied customer !!!