"Are girdles generally added for big rpm or HP or torque". What's your intentions? Circle track, 14-1, billet splayed caps, fuel=alcohol? Or maybe not so much? Total overkill! You don't need it. Yeah, it's a chev.
I ran one last year for the first time. 576 HP, and I ran it HARD. At disassembly couple weeks ago there was absolutely no sign of main cap walking. None.
At the very least it will eliminate walk and sort of act like a crank scraper. Anything we can do to sturdy up these flimsy little 2 bolt caps we're stuck with, is a plus in my eyes.
Had a 414 stroker that I ran a couple years, it made 515Hp, when I took it to the machinist he showed me the signs. Number 2 and 4. Pretty bad so he said. It ended up being a "shot" block in the end, so we didn't have to address the issue.I have to ask, in the past, you have noticed cap walk in past engines?
In the current engine that makes use of the girdle, what kind of useage did it see and for how long?
Thanks Mike.
Yes to all 3.
But, I wonder where that power level begins....I think that's the simplest answer.
The flat girdles I've seen do little for rotational twisting; they simply do not have adequate strength in that direction. They only tie the caps together front-to-back and so reduce 'tilting' of the caps.
IM, in relations to Rumble's question.... did your machinist explain what is causing the cap walk?Had a 414 stroker that I ran a couple years, it made 515Hp, when I took it to the machinist he showed me the signs. Number 2 and 4. Pretty bad so he said. It ended up being a "shot" block in the end, so we didn't have to address the issue.
Current engine ran last year 2100 miles. It never leaves the garage without a couple passes. Pretty hard use. Had to tear it apart to ease my own mind, but the maincaps look new as well as the block mating surfaces. This is a 4 speed car with 430 gears and pretty sticky tires. No walk at all.
I don't consider wasting money on anything in my motor that MIGHT help. It can't hurt.
Same question to FB... Is there an explanation of what is making the caps/studs to whip around? Is this just crank flexing working through the bearings, or some resonance, or ???? This article for Ford mentions 'harmonics', which indicates resonant problems.didn`t read all these posts, but some of u guys are missing the point. A girdle will strengthen a big block/r/b, probly more than any other block made , just because of its weak design. The girdles purpose is to stop the mainstuds from whipping around causing cap walk that breaks the block between the main and cam bores, in a ''higher'' h.p. hi RPM situation. More for engines that are run all the time in upper RPM . There are a lot of tricks to be used, all of them together should make a 440 , which is the worst , more dependable and last longer. In my case I use one because I don't want any future troubles, not that I run at higher rpm a whole lot.
Alum. main caps w/ studs , main studs by them selves , girdles , cryo treatment , block filling , line honing/boring , all will help a r/b .
A mega type block would solve a lot of this "if," u can afford one.
I`ve always had to buy parts a little at a time , never could afford to come up w/ a mega , or alum. aftermarket block all at once .
Some blocks will break in that area faster than others . I know a guy that even broke mega blocks between the main and cam bores " ,
dragcar-----------he eventually backed the linkage off to run consistant 9: 60`s, with alum. caps and studs .
I built a really hot 406sbc, that I had machined for 4 bolt mains , it still cap walked on every cap------
I don't remember if he ever explained it I do remember very well that he said "wait a minute"....... walked away and came back and put a factory SBC 4 bolt cap on his desk, next to mine. Pretty dramatic difference.IM, in relations to Rumble's question.... did your machinist explain what is causing the cap walk?
Same question to FB... Is there an explanation of what is making the caps/studs to whip around? Is this just crank flexing working through the bearings, or some resonance, or ???? This article for Ford mentions 'harmonics', which indicates resonant problems.
D.S.S. Racing - Main Support System And Pro-Tray Windage Control<meta name="description" content="D.S.S. Racing's Main Support System Dampens Harmful Harmonics That Cause Cap Walk And Can Crack Engine Blocks. The Main Support System Is Affordable And Easily Installed. D.S.S. Also Offers Increased HP With The Pro-Tray Windage Control.">
And yes, the girdles have the strength to control this direction of movement. This sounds like a good explanation. Many thanks!
What about the actual size of the 340 journals?The 340 shouldn’t be any more prone than another engine except that it does produce more power and torque just in cylinder size. All else being equal.
Crank main journals are 2.50 for everything except the 360 which is 2.81. All rods are 2.125.What about the actual size of the 340 journals?
Exactly. more material around the main, so saying a 340 would be more prone is just plain oversight...Crank main journals are 2.50 for everything except the 360 which is 2.81. All rods are 2.125.
Oh man! I don't know why I was thinking the 340 was BIGGER. I had it backward. So in my mind, I guess the 360 might be more prone to cap walk.Crank main journals are 2.50 for everything except the 360 which is 2.81. All rods are 2.125.
The shop that originally built my SB 383 said the Mopar's seldom have block issues if you stud the mains. I asked about Mopar girdles at the shop that built my kid's SBC... he said he never sees crank or block issues with SB Mopars...
My engine is a mild 575 hp deal that will run just north of 7,000 rpms on a 1/2 mile dift track.
I was wondering the same thing. I've been involved in dirt racing my whole life and the last time I even heard of a production block Chrysler running was in the 80's. And yes, I never saw a LA block break. I attribute that to the fact that something valvetrain related always parked them first. And the ones I saw were in the lower stock and sportsman divisions (about 400hp back then).What does a "mild" 575 hp small block combo look like?
How are they “Not even remotely MoPar” if there running MoPar R/A blocks and a W series head?In later years some guys ran the R/A/W/5/7/9ect ect. Those engines were very competitive, cost a fortune, very difficult to get parts for, and were not even remotely Mopar.
A Mopar part number, yes...even remotely related to a small block Chrysler, no. Chevy deck height, Chevy oiling, Chevy valvetrain angles and locations, off the shelf Chevy rotating assembly, accepts Chevy front accessories, Chevy trans bolt pattern, heads are a modified copy of the Chevy SB2 and RO7. So yup, 95% Chevy, 5% custom, and 0% Mopar. Not one single piece of these engines is compatible with a Chrysler small block. They did have cool Mopar valve covers though.How are they “Not even remotely MoPar” if there running MoPar R/A blocks and a W series head?