Main cap girdles re-discussed

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For the proponents of the Mopar small block girdle that Hughes and probably other sell. Do you think it ads strength and helps prevent cap walk? If so, explain.
 
I was just rereading a thread I commented on a long while ago about main cap girdles and the ending consensus was a no..... HOWEVER I did read it and it seemed to me that everyone was only implying it to 2 bolt main girdles on an LA factory block. Now I do understand that some people still run 4 bolt caps and leave the outer bolts unused just to help transfer the stress across a more broad surface area. So my question is what does everyone think about running 4 bolt caps for that and adding a girdle on top? Yay? Nay? Why?
I run a girdle on my 340 block and I'm putting out about 625 HP on alcohol. The main caps had to be machined down where the stud nuts and washers set, this way I didn't have to shim to get the girdle to fit evenly across all the main caps. Been running it hard for 6 seasons and the main bearing look like new. Running 6.50 sec. to 6.67's at 101 - 102 mph in the 1/8th depending on the air, tune and traction.

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I run a girdle on my 340 block and I'm putting out about 625 HP on alcohol. The main caps had to be machined down where the stud nuts and washers set, this way I didn't have to shim to get the girdle to fit evenly across all the main caps. Been running it hard for 6 seasons and the main bearing look like new. Running 6.50 sec. to 6.67's at 101 - 102 mph depending on the air, tune and traction.


Must be a heavy car. 6.50-6.67
That’s what my sons stock crank 360 ran and it wasn’t 600 horsepower.
 
Yep, disagree all you want but I have experience on my side.
If I'm being honest.. the more you post, the more sure I am that you are greatly overestimating your own abilities and knowledge.

In another thread you were saying you don't even recognize that mopar shaft rockers work well and you got hit with the facts regarding their use in top fuel Hemi enginess and got slapped down like a little *****.

Your opinions don't hold much weight to me, Just saying.

And every example you posted is nothing like a girdle like we are discussing.

I didn't post any examples of girdles. I listed engine applications that they have been used successfully on.

This is literally what you asked me to do when you said "In what applications have YOU seen them work?" In post #42.

So there is that. And I’ll say it again just to irritate the general public. If you are having issues to the point you think you need a girdle, or a block fill or both you need to save your money and buy a block.
Your opinion is noted, thank you for sharing.
Unless of course you think the factory is stupid and the aftermarket is stupid and the people who buy good blocks are stupid. Then you are on your own.
I don't think the factory is stupid.
The factory isn't trying to make engines live at 1000+hp. Which would be a valid reason to not run stud girdles even if they were 100% proven to always work.

I don't think the aftermarket is stupid, but apparently you do because you're claiming aftermarket stud girdles can never ever work on anything no matter what.

I don't have delusions that every product on the aftermarket will always work, but I think there are quite few aftermarket products which never work.
Including main cap girdles.
One more time for clarity.

A main girdle doesn’t work no matter how bad you want
it to.
One more time, your opinion is noted Thanks for sharing.
 
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If I'm being honest.. the more you post, the more sure I am that you are greatly overestimating your own abilities and knowledge.

In another thread you were saying you don't even recognize that mopar shaft rockers work well and you got hit with the facts regarding their use in top fuel Hemi enginess and slapped down like a little *****.

Your opinions don't hold much weight to me, Just saying.



I didn't post any examples of girdles. I listed engine applications that they have been used successfully on.

This is literally what you asked me to do when you said "In what applications have YOU seen them work?" In post #42.


Your opinion is noted, thank you for sharing.

I don't think the factory is stupid.
The factory isn't trying to make engines live at 1000+hp. Which would be a valid reason to not run stud girdles even if they were 100% proven to always work.

I don't think the aftermarket is stupid, but apparently you do because you're claiming aftermarket stud girdles can never ever work on anything no matter what.

I don't have delusions that every product on the aftermarket will always work, but I think there are quite few aftermarket products which never work.
Including main cap girdles.

One more time, your opinion is noted Thanks for sharing.


You are 100% ignorant if you think the Chrysler rocker shaft system is anything but MARGINAL at best.

Once again, it’s evident you haven’t a CLUE what it takes to make power at a respectable RPM. Five 3/8 bolts will NOT hold the rocker shafts anywhere near rigid you need to stick to golf.

And then the passenger car heads have five 5/16 bolts!!! Trying to run a roller cam and any RPM over maybe, MAYBE 6k is DEATH to the valve train.

Lets talk about the much vaunted Hemi and it’s shitty rocker hold down system. And it’s stupid long exhaust rocker.

There are 5 (FIVE!!!) 7/16 bolts (or studs depending on how its put together) to hold down TWO opposed shafts. How in the **** do you think that works?

The answer is it barely does. BARELY. The shafts move all over the place.

Maybe rather than posting here you need to go find some Spintron video of different rocker systems and see how bad this 5 bolt Chrysler **** is.

Then go look at something like MBE or Steve Morris’s SMX engines mount their rockers.

Continue to think you have a clue about what a race engine is and does.

You wankers only play with garbage so you can’t see the difference.

BTW, look at the Alan Johnson 481X engine and see how he built the rocker gear for that.

I finagled my way into a full set of engineering drawings for the W5 head. Took me a year of digging before I found someone who could hook me up.

I spent TWO YEARS working with the drawings to unfuck that head. The W7 was discontinued and the W8-9 stuff required too many parts that didn’t interchange with W2-5 stuff and I know, for a FACT that if a guy can’t use most of the stuff he has he won’t even sniff something new.

When I finally had some roughed in dimensions and ideas I got on the phone. The cost just to get the first set of core boxes was astronomical.

Also finding a foundry to run the castings was about impossible.

That head would have easily gone 420 CFM with a reasonable port window. AND, I addressed the shitty rocker mounting issue. It would have had eight 1/2 inch studs plus eight 7/16 perimeter studs.

Of course, getting all that done was a task but in the end reality sets in. Chrysler guys will never upgrade to something like because too many think like you do.

You retard the industry.

Piss off wanker.
 
You wankers only play with garbage so you can’t see the difference.
Show us what you have ? I'd like to see it.
Better still, show us the head drawings
 
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You are 100% ignorant if you think the Chrysler rocker shaft system is anything but MARGINAL at best.

Once again, it’s evident you haven’t a CLUE what it takes to make power at a respectable RPM. Five 3/8 bolts will NOT hold the rocker shafts anywhere near rigid you need to stick to golf.

And then the passenger car heads have five 5/16 bolts!!! Trying to run a roller cam and any RPM over maybe, MAYBE 6k is DEATH to the valve train.

Lets talk about the much vaunted Hemi and it’s shitty rocker hold down system. And it’s stupid long exhaust rocker.

There are 5 (FIVE!!!) 7/16 bolts (or studs depending on how its put together) to hold down TWO opposed shafts. How in the **** do you think that works?

The answer is it barely does. BARELY. The shafts move all over the place.

Maybe rather than posting here you need to go find some Spintron video of different rocker systems and see how bad this 5 bolt Chrysler **** is.

Then go look at something like MBE or Steve Morris’s SMX engines mount their rockers.

Continue to think you have a clue about what a race engine is and does.

You wankers only play with garbage so you can’t see the difference.

BTW, look at the Alan Johnson 481X engine and see how he built the rocker gear for that.

I finagled my way into a full set of engineering drawings for the W5 head. Took me a year of digging before I found someone who could hook me up.

I spent TWO YEARS working with the drawings to unfuck that head. The W7 was discontinued and the W8-9 stuff required too many parts that didn’t interchange with W2-5 stuff and I know, for a FACT that if a guy can’t use most of the stuff he has he won’t even sniff something new.

When I finally had some roughed in dimensions and ideas I got on the phone. The cost just to get the first set of core boxes was astronomical.

Also finding a foundry to run the castings was about impossible.

That head would have easily gone 420 CFM with a reasonable port window. AND, I addressed the shitty rocker mounting issue. It would have had eight 1/2 inch studs plus eight 7/16 perimeter studs.

Of course, getting all that done was a task but in the end reality sets in. Chrysler guys will never upgrade to something like because too many think like you do.

You retard the industry.

Piss off wanker.

11,000hp top fuel hemi engines are marginal at best?
Reading you loud and clear.
Your opinion is noted. Thank you for sharing.
 
11,000hp top fuel hemi engines are marginal at best?
Reading you loud and clear.
Your opinion is noted. Thank you for sharing.

You’re shutting me right? You think that a fuel engine doesn’t have valve train issues?

They sure do. They do the best with what they have. NHRA has a rules package that won’t let them move enough **** around to fix it. Or at least make it more tolerable.

And that means you think guys like Matt Bieneman and Steve Morris are stupid because they have addressed the issue. Thats the height of arrogance.

You opinions have been duly noted and thrown in the dumper as uneducated nonsense.

BTW, just to show you even in a class like Pro Stock **** isn’t what you think it is.

So here is a TRUTH.

In 1996 at the Seattle Nationals I was privileged to be allowed past the rope in the Johnson and Johnson Pro Stock pits. I couldn’t take any pictures but I could look at anything I wanted.

At that time, they were qualifying 15-16 at best and May times they were in the low 20’s depending on how many cars there.

Roy Johnson was leaking the engine down and 3 and 5 were at 15%. That’s horrible for anything. For a Pro Stock engine that’s junk.

So I asked why it was so bad. He said “do you see that head stud right there?” I said yes and he said “its in the wrong spot!”

Being the dumb *** I am I said why don’t you move it?

He said “because Chrysler won’t redo the head so we can move it”.

So there you go. The ONE Chrysler Pro Stocker out there was sucking hind tit because Chrysler wouldn’t do the work to change the casting, change the gasket and get NHRA to approve it.

What you don’t know exposes your folly. You can babble on like a fool but anyone paying attention can see you don’t have a clue.

Take a hike.
 
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You’re shutting me right? You think that a fuel engine doesn’t have valve train issues?
That isn't my claim.

My only claim is that the following assertion is total bullshit.
Five 3/8 bolts will NOT hold the shafts down under load unless you run hydraulic cams or really small SFT stuff.
And the fact that top fuel hemis run five 3/8" bolts per rocker shaft just blatantly proves it.

I've noticed an amusing pattern, whenever someone questions your bullshit claims, you consistently try to pull rank and act as if you're an industry hero whose opinion needs to be taken as gospel and anyone who disagrees is some kinda peasant

It's an internet forum, Nobody knows or cares who you are or who you claim to know.

if you can't bring the evidence or back up your theory with science. You have an opinion, that's all.

I've got no clue why your account hasn't been nuked yet. You're pretty much a cunt to everyone you interact with.

You've stated your opinion, I've stated mine.
So I'll kindly ask you to not try to put words in my mouth.
 
So a question if yall can stop feudin long enough. Those of you who seem to oppose stud girdles, are yall saying that even a big block stud girdle that tied the mains and the oil pan rails together adds zero strength?
 
I've noticed an amusing pattern, whenever someone questions your bullshit claims, you consistently try to pull rank and act as if you're an industry hero whose opinion needs to be taken as gospel and anyone who disagrees is some kinda peasant
I've got no clue why your account hasn't been nuked yet. You're pretty much a cunt to everyone you interact with.
That's his pattern alright.
He's had his account Nuked a few times. But in this place, a new account name gives you a clean slate. Makes you wonder why they bother to permanently ban a user to begin with.
 
So a question if yall can stop feudin long enough. Those of you who seem to oppose stud girdles, are yall saying that even a big block stud girdle that tied the mains and the oil pan rails together adds zero strength?


I‘m saying yes. It not only does nothing, it actually screws **** up.

If you can find a Hemi block you can lay it next to a standard wedge block and see the differences.

The stud girdle, the cross bolt caps and all that junk won’t do anything but lighten your wallet on a standard block.

Any time you take the load from one main bearing and try to spread that load to other bearings you set up a giant tuning fork. And as Randy Neal from CWT says “once you excite one part of the system you can’t stop it”.

There are three things (well four but I forgot one as I typed that) you can do to help these blocks survive. The problem is no one likes to hear the truth of it.

1. Aluminum main caps.
2. Main studs.
3. Aluminum rods.
4. A crank damper that doesn’t have rubber in it.

Thats it. Anything else is just eating money for no benefit.

And yes, I’ve done engines with stud girdles because the customer thinks he is smarter than everyone building engines. And bet your *** when it comes back in the main bearings will be showing distress in every kind of way you never see with anything else.

Of course the customer doesn’t see it or know it because they deal with one engine and they don’t know what they are looking at.

Ive also installed them on some stuff that didn’t need anything but the girdle sounds cool when you are leaning on the fence at the drag strip telling your buddies all about your cool **** while your junk is at home because it’s so slow a Prius would give it a hard run for the money.

Or when you come to places like this.

Just think about it Rob. Think about the load on the front main cap. Then think what happens when you spread that load to another cap that isn’t getting oil in the journal to form the wedge that keeps the crank off the bearing.
 
I‘m saying yes. It not only does nothing, it actually screws **** up.

If you can find a Hemi block you can lay it next to a standard wedge block and see the differences.

The stud girdle, the cross bolt caps and all that junk won’t do anything but lighten your wallet on a standard block.

Any time you take the load from one main bearing and try to spread that load to other bearings you set up a giant tuning fork. And as Randy Neal from CWT says “once you excite one part of the system you can’t stop it”.

There are three things (well four but I forgot one as I typed that) you can do to help these blocks survive. The problem is no one likes to hear the truth of it.

1. Aluminum main caps.
2. Main studs.
3. Aluminum rods.
4. A crank damper that doesn’t have rubber in it.

Thats it. Anything else is just eating money for no benefit.

And yes, I’ve done engines with stud girdles because the customer thinks he is smarter than everyone building engines. And bet your *** when it comes back in the main bearings will be showing distress in every kind of way you never see with anything else.

Of course the customer doesn’t see it or know it because they deal with one engine and they don’t know what they are looking at.

Ive also installed them on some stuff that didn’t need anything but the girdle sounds cool when you are leaning on the fence at the drag strip telling your buddies all about your cool **** while your junk is at home because it’s so slow a Prius would give it a hard run for the money.

Or when you come to places like this.

Just think about it Rob. Think about the load on the front main cap. Then think what happens when you spread that load to another cap that isn’t getting oil in the journal to form the wedge that keeps the crank off the bearing.
But aluminum rods have a "shelf life" in the engine. Or are there some mead these days that will live like steel? .....and WHAT is the possible advantage to aluminum main caps? I'm wantin to be ejeekated here.
 
But aluminum rods have a "shelf life" in the engine. Or are there some mead these days that will live like steel? .....and WHAT is the possible advantage to aluminum main caps? I'm wantin to be ejeekated here.

You can run aluminum rods on the street. Oil temp and bearing clearance is critical. Bill Miller has some discussion about this on his home page.

Aluminum rods do have a shorter life, but most every big power Drag & Drive type engine is using aluminum rods.

Aluminum rods take up a huge amount of shock in the system.

Aluminum caps do the same thing. Like I have said before, everything has a resonance frequency. If you change the frequency of something you change how it behaves.

An example of that is a flimsy pushrod. They too can start vibrating like a tuning fork. And they bend and unbend under load. When that pushrod unbends all the stored energy in it is like a jack hammer. It will loosen nuts and bolts and crazy things like that. Rocker adjuster nuts, bell housing bolts…starter bolts.

I had a customer with a MFI 377 Chevy. The F’ing starter kept coming loose. We used red locktite and all that did was make it take longer to get loose.

Tearing it down after some dyno pulls (killed a set of springs on the dyno after about 10 pulls) we noticed witness marks where the pushrods were rubbing the head and it had .100 clearance.

We ordered up a new set of pushrods with a bigger diameter (cheap assed 5/16 .060 wall to 3/8 .120 wall) and the starter bolts never came loose again.

You can never underestimate what something vibrating in the wrong frequency will do.

Main studs moves the screw load out of the bolt hole and up to the nut. Now the threads see only a straight pull against them. It’s changes how the block sees the clamping load.

The damper has to deal with all this **** flexing and vibrating. Elastomer dampers (doesnt make a pinch of **** difference who’s name is on it) have an incredibly narrow tuning range. Pro Stock and ASScar teams and some very well funded sportsman classes all have engineers on hand a dyno’s fully outfitted with measuring tools that can plot the amount, duration and intensity of the crank bending.

When they have that data they can change the durometer (and maybe the diameter but I’m not 100% sure of that) on the O rings in the damper to change the frequency to calm the crank down.

Guys that are hell bent on pinching every single penny they can fail to understand the consequences of what happens when you change ANY one component that relates to the crank.

When Chrysler developed an engine package they spent millions of dollars testing stuff like this. And they considered the most expected operating range their passenger car engines would likely use.

With that operating range established, they developed the damper that would be most effective in THAT a RPM range with that crank weight and materiel, that connecting rod and weight and that piston and weight.

Change any ONE of those components, just ONE and you have effectively made the damper less effective.

Now let’s just jack everything up. Let’s think it through.

Chrysler figured the engine would spend the majority of time at cruise RPM. That’s easy to figure. Say a 25 inch tire with a 3.23 rear axle ratio and you are right about 3000 RPM. Roughly.

So they built a damper that would be the most functional at that RPM because that’s where the engine would spend the most time. And don’t forget that even if you have a harmonic issue as long as you get through it you can live with it.

Now we come along and the first thing we do is go to a lighter piston. And we have now made the damper less effective in two ways. It’s probably lighter and it’s a different materiel with a different resonance frequency. Oh ****. But we keep going.

We throw some cam it, slam some barn door capable valve springs in there and we start RPM’ing the engine way higher than what the damper was designed for. But we still have that OE damper.

That big cam sounds cool and all but it’s a bit piggy down low so we run down and grab some 4.56’s off the shelf (this is back when men weren‘t afraid of gearing the **** out of something and you could buy the stuff local) and you slam those mothers in there.

Now you can rotate the earth but your cruise RPM is now significantly higher than what Chrysler planned for. And the OE damper is still hanging on the crank. But we have changed the piston weight, piston materiel and RPM range the engine typically operates in.

Now we are bored. So we say **** it, I’m going to light up the sky and we stick the hose to it. We decide a 150 shot of nitrous will do the trick (add in any power adder here…I used nitrous because it’s my favorite power adder) and impress not only our buddies but all the hot chicks (hot chicks used to dig fast cars…now they want a guy with a Honda and a fart can and a cool phone…thank GOD I’ll be dead soon) and off we go.

Now the cylinder pressure is much higher than what Chrysler ever intended. And…we still have the OE a damper on there.

After a few hits on the street, smoking the tires like only Joe Camel could, a couple of rods **** the bed and uncouple from the crank. Nitrous is like a hooker, you KNOW you want to hit it but the consequences are usually never good.

Now we decide we need more. So we get a nice long stroker crank (thats one big change) and instead of being 1018 materiel (thats what Chrysler used) it’s 4340 and it’s a non twist forging instead of a twisted forging like Chrysler used) so that’s THREE big changes. Stroke length, crank materiel and forging process and which affect its resonance frequency.

Of course, two rods are now hanging on the wall of shame so we say FTW! And buy some really nice H beam 4340 forged rods. Now we have changed two more critical components and their frequencies but we still use an OE damper that was never designed for any of this.

We have all this new **** together and off we go. All the girls want jump in the car and all your buddies are jealous. After a year or so the power is down (if you’re lucky it makes it a year) so out the engine comes and we take it apart.

The main bearing look like fresh baked garbage and we hit the interweb where all the experts hang out (and of course none of the experts agree with each other!!!) and the general consensus is we NEED a main girdle.

Is a picture forming in your mind of how absurd this is?? It should be.

We have done everything we can to make the crank damper as ineffective as we can and **** is getting trashed. So the answer is to use some rinky dink piece of 3/8 plate (maybe half inch of the manufacturer really wants to impress the customer) with 10 holes in it to make the try and make the block stronger and more ridged when most of the time the block isn’t the issue.

The last thing we do is consider what changes we have made and how that affects the damping ability of the OE damper.

As I have pointed out many times, the elastomer damper has a very limited damping range. It’s big selling point is it’s cheap to build and relatively effective in it’s tuned range. Other than that, it’s not worth a **** really.

I‘ve told this story before but I’ll repeat it here because it fits the discussion.

In 1988 I switched to aluminum rods. I was also going from shifting at 8k to 8500 or if I could get it 8800. And I could see the main bearings were pissed off.

It was time upgrade from the OE damper and all the big hitters were using the much vaunted ATI “Super Damper” (its always a clue for me when the marketing department puts “super” in the name so I’m skeptical) so I had all my info at hand like Bob weight, crank weight (the 8 bolt cranks weighed more than a production 6 bolt and had a different heat treat which affected the frequency) and called ATI.

I figured that they would have to build me a custom damper to deal with what I was doing. Fat chance.

I tell the clown on the phone that I need a damper for a small block Chrysler. He interrupts me and gives me a part number. I have the catalog right there and it’s their off the shelf piece.

So I say dude, my bob weight is about 200 grams LESS than what most guys use and I don’t know anyone near me shifting at 8500 or a bit higher. Don’t you think I need a custom damper?

He says nope, our dampers are so sophisticated it controls damping at most frequencies. And I promptly told him he was full of ****. Even in 1988 you could find research into this stuff and the elastomer damper has the most narrow effective range of any style of damper.

I said can you make me a custom damper. He said why? Rather than continuing on a conversaction with a guy who was crapping in my mouth and telling me it was chocolate cake I said buy-bye and hung up.

As far as I know 01/25/2023 there are only TWO dampers that have a wide frequency range. Fluidamper and Innovators West. If you look at some Steve Morris builds he uses mostly Innovators West.

During the 2023 Engine Performance Expo (I posted a notice in the racers forum…hopefully people took advantage of it) John Callies gave a lecture on cranks and in it he advocated for the new aluminum Fluidamper. I know he didn’t like the steel Fluidamper because when they first came out guys were not fitting the damper to the crank snout. If the damper was too tight it would split the damper at the keyway and off came then damper. Or they were too loose (the beginning of the china crank era was filled with cranks with undersized snouts) and the damper didn’t work and off came the damper with the snout in it.

So I said all of that to sum it up.

The damper is far more critical than people think. If someone is running an elastomer damper they may want to spend some time looking at the available research out there and question why they are doing it.

And before 67 dudes chime in and say they have been running an elastomer damper for 30 years and never touched it I‘ll say it’s better to be lucky than good.

It’s a testament to how shitty a build can be made and have it live.

And ATI has recommended service intervals for their dampers.

From the day an elastomer damper, any elastomer damper is made it is degrading.

Bet your *** on that. And no stud girdle will fix that.
 
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We've gone from debating stud girdles to top fuel valve train, LOL

On a small (production) block What do you guys think it helps? Prevent cap walk? Increases block rigidity? Something else?
 
We've gone from debating stud girdles to top fuel valve train, LOL

On a small (production) block What do you guys think it helps? Prevent cap walk? Increases block rigidity? Something else?

Did you read post 67?

Summation: a stud girdle can’t do anything if you push the block past it’s power limit and that’s much lower than people think.
 
Did you read post 67?

Summation: a stud girdle can’t do anything if you push the block past it’s power limit and that’s much lower than people think.
Yes. I was looking for the reasoning of guys that think they work. My opinion is they are designed to move money, from users pockets to sellers pockets.
 
And yes, I’ve done engines with stud girdles because the customer thinks he is smarter than everyone building engines.
Ive also installed them on some stuff that didn’t need anything but the girdle sounds cool when you are leaning on the fence at the drag strip telling your buddies all about your cool **** while your junk is at home because it’s so slow a Prius would give it a hard run for the money.

Or when you come to places like this.
Yet in another thread a while back you've said that you tell your so called "customers" to take a hike when they try to tell you how to build an engine by wanting to put parts they didn't need or don't work into it.
You would say anything, or claim to have done anything to try and shaw up your arguments.
Gonna have to start calling you Anthony Devolder...
 
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My opinion is they are designed to move money, from users pockets to sellers pockets.
Maybe....but has anyone posted any hard data on the subject?
Before and after pics of using one, etc?
 
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