Rod Question / help

[dirtbandit]

I have a set of h-beam rods that feature a "force feed oiling system", with 1.88 honda journal size and take a .867" wristpin. The rods weigh 560 grams and are .780" wide.
These are 6" rods with sps carr 3/8" rod bolts.

Would these be ok to run in a ump/umsts modified motor and live? 388 cu in around 650 -700hp? I was concerned about the width also.
Other than needing a crank with 1.88 rod journals, is there anything else i need to be aware of in regards to the crankshaft.

Thanks for your replies.

[TBRE]

rods

They wiil work fine for what you're wanting to do. We can get your parts for you if you don't know where to shop. The pistons will need to guide the rods, either with a small inboard box forging, made .005 wider than the little end, or get spacers made, and remachine conventional forgings.
We have a used, low milage crank for that engine (350 main/1.8885 rod Callies), call for details. 601-847-4744

[dirtbandit]

Thank you for the response. We were told by a local builder and by callies that these nascar rods are too light and would fail under this application.

[fast_crew]

Besure to run a lite weight piston and pin and you should be fine, as long as you don't twist the guts out of it. You will need casidium coated pins if those rods don't have bushings.

[dirtbandit]

would you say that 8400-8600 rpm is twisting the guts out of it?

[giffordracing]

don't they use that same deal in CUP motors at 800+ hp at 9000rpm....Or the older cup motors..SB2.2....Nascr has a 500 gram rule on rod and most all them are low 500 to 575

[TBRE]

rods

The reason I think he will be fine is,
1: he's running against them, and
2: the 560 gram rod came out of an open engine, the plate stuff is closer to 500.
Mag them, measure the bolt stretch, run a light piston/pin, and you'll be fine.TB