To the engine experts:
I was looking through the Jeg's catalog and saw that they had Forged Eagle H-beam Connecting Rods for the Ford 351 Cleveland that is 5.78 inches long.
Here's the description:
"Heat treated, stress relieved, certified 4340 steel 2-piece forgings for increased strength. X-rayed, sonic tested, magna-fluxed, all surfaces 100% machined with extremely tight tolerances, bronze bushings for floating pins. ARP 7/16” 8740 cap screw bolts with a stroke design for monster cam clearances."
The VH45DE rods are 5.7854 inches long with a .9835" small end and a 2.1654" big end.
The Eagle H-beam rods for the 351-C are 5.780 inches long with a .927" bushing (might be .927 without bushing) for the small end and a 2.310" big end. They also come with the 7/16" ARP bolts and weigh 660 grams. The price in the Jeg's catalog is $499.99.
I was wondering if this has any potential use in the VH45. How much work do you think it would take to make them fit? Is it even worth the trouble?
Modified by sijoko at 12:24 PM 8/23/2006
Aftermarket Connecting Rods for VH45DE?
The big end bore is what is preventing these rods from being used. Also, when I measured the pin end of the VH45 rod, I came up with .865" for the size of the pin.
Where you will find rods that work are small journal chevy rods (2.1"). They will only need to be narrowed and the VH crank will only need to be undersized down to sbc journal size.
A rod more like this will be easier to get to work in a VH. All it will need is to have the big end width narrowed, and you can offset grind your VH rod journals when they are turned down to SBC size to get the right quench.
Where you will find rods that work are small journal chevy rods (2.1"). They will only need to be narrowed and the VH crank will only need to be undersized down to sbc journal size.
A rod more like this will be easier to get to work in a VH. All it will need is to have the big end width narrowed, and you can offset grind your VH rod journals when they are turned down to SBC size to get the right quench.
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sijoko
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Re: (defrag010)
Ok, I understand what you mean about the big end measurement being too large on the 351C rods.
So what we want are rods that have a smaller big end than the VH rods such as the Chevy SBC rods you linked.
Now, how about using 6.00" rods that have smaller 1.850" big ends. The rod journals on the VH crank are 2.046".
Can an offset grind take care of the longer rods? Wouldn't the engine also pick up some displacement?
The reason I ask is that one can pick up a set of used Carrillo 6.00" rods on eBay for $300. These are used on Nascar engines and are replaced on a regular basis.
Check out this auction: http://cgi.ebay.com/ebaymotors...wItem
Also, the small end measurement that I gave for the VH rods is without the bushing. It is .8661 with the bushing installed according to the FSM.
Incidentally, the Carrillo rods in the auction have a .867 small end so that is a plus.
Modified by sijoko at 9:13 AM 8/24/2006
So what we want are rods that have a smaller big end than the VH rods such as the Chevy SBC rods you linked.
Now, how about using 6.00" rods that have smaller 1.850" big ends. The rod journals on the VH crank are 2.046".
Can an offset grind take care of the longer rods? Wouldn't the engine also pick up some displacement?
The reason I ask is that one can pick up a set of used Carrillo 6.00" rods on eBay for $300. These are used on Nascar engines and are replaced on a regular basis.
Check out this auction: http://cgi.ebay.com/ebaymotors...wItem
Also, the small end measurement that I gave for the VH rods is without the bushing. It is .8661 with the bushing installed according to the FSM.
Incidentally, the Carrillo rods in the auction have a .867 small end so that is a plus.
Modified by sijoko at 9:13 AM 8/24/2006
I wouldn't turn the VH crank rod journal down that small. When you start turning the journals down over .100", you run into problems.
I used to buy up and re-sell all that used nascar stuff on ebay all the time (yates and SB2.2 pistons, ti valves, carillo rods, etc) and found out that they are all bastard sizes.
If you are going to go all out on getting a rod to fit, you can simply take the longer rod and use a piston with a shorter compression height. With a crank offset -.006" and undersized to 2.100" on the rods, along with an overbore of 94.9 mm, you could use Chevy 305 Forged pistons with Chevy 400 H-beam rods narrowed .075" on the big end.
I used to buy up and re-sell all that used nascar stuff on ebay all the time (yates and SB2.2 pistons, ti valves, carillo rods, etc) and found out that they are all bastard sizes.
If you are going to go all out on getting a rod to fit, you can simply take the longer rod and use a piston with a shorter compression height. With a crank offset -.006" and undersized to 2.100" on the rods, along with an overbore of 94.9 mm, you could use Chevy 305 Forged pistons with Chevy 400 H-beam rods narrowed .075" on the big end.
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ZedZillaZ32
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Re: (defrag010)
"If you are going to go all out on getting a rod to fit, you can simply take the longer rod and use a piston with a shorter compression height. With a crank offset -.006" and undersized to 2.100" on the rods, along with an overbore of 94.9 mm, you could use Chevy 305 Forged pistons with Chevy 400 H-beam rods narrowed .075" on the big end."
Will that be an acceptable route to go if I wanted to TT or supercharge the engine? Im trying to figure out a way to drop the compression for the above purpose without the guy at the rebuilder saying sure trhat'll just set you bad your life saving hehehe if it also strengthens the engine even slightly that would be a bonus
Will that be an acceptable route to go if I wanted to TT or supercharge the engine? Im trying to figure out a way to drop the compression for the above purpose without the guy at the rebuilder saying sure trhat'll just set you bad your life saving hehehe if it also strengthens the engine even slightly that would be a bonus
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maxnix
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Re: Possible Aftermarket Connecting Rods for VH45DE. (sijoko)
I have to say I find it strange that anyone would try fitting parts designed in SAE English measurements to a metric engine with tolerances of thousandths of a millimeter in some parts.
Better be able to specify those SAE units out to six decimal places!
Better be able to specify those SAE units out to six decimal places!
zedzilla, there are tons of 305 pistons available with as big or small of a dish size as you want, so you can calculate compression based on the quench, the piston dish size, and the head cc.
maxnix, what are you talking about? people hardly use the metric system when setting clearances, and even so, you can convert units. example: getting a crank journal cut down .25mm or .010". What engine part are you talking about that is measured down to the thousandth of a millimeter? The smallest measurement I can think of off-hand are bearing clearances.. and they only go down to the 4th decimal place at the most (ex. .0015").
maxnix, what are you talking about? people hardly use the metric system when setting clearances, and even so, you can convert units. example: getting a crank journal cut down .25mm or .010". What engine part are you talking about that is measured down to the thousandth of a millimeter? The smallest measurement I can think of off-hand are bearing clearances.. and they only go down to the 4th decimal place at the most (ex. .0015").