like the title says more then likely im going to have a 400 here real soon..i keep hearing about rapid cylinder/piston wear,but is this only a concern(and how big of one)for a daily driver?also are there any reliability issues with such a crappy ratio?any idea what kind of miles a stock 400 motor gets till its work out from the rapid wear?thanks in advance...

I have a buddy that runs 11's with stock 400 rods, crank and cheap flattops hes run the same motor for at least 5 years.

IMO, there is such a small difference between 5.565 and 5.7 rods, it's negligible, IMO. My engine is a grand total of nearly 10 years old. I had it apart 2 years ago to change pistons and it only needed a backyard hone http://www.nastyz28.com/ubb/wink.gif

The rotating mass is probably more of a concern than the rod ratio. I'll get you some weight comparisons between a stock 5.565, vs. 5.7 Scat rod, and stock 1.56" compression height flat top and a KB 1.425" compresion height Hyper. Less weight swinging around on the end of the rod means less wear and a motor that will RPM better.
Just happen to have a fresh set of KB hypers and Scat 5.7 rods sitting here.

Hyper w/ D dish (11ish cc) 4.165 bore, 3.75" stroke, for 5.7 rod: 557g.

Scat profiled I-beam 5.7" rod: 584g.
(sorry, no fixture to accurately weigh big end / small end but the 5.565 would probably slightly edge out the 5.7 there)


Check back later and I'll punch one of the 4.155" flat tops and stock rods apart this afternoon and get you some weights for a comparison.

I have stock 400 rods in my 406 now.

They are fine, but I didn't rpm it much above 6 to 6200 or so..

No need to with all the grunt.. Even with my mis-matched 292 hy-cam and about 9.5 to 1 CR.

pdq67

i ran stock crank, short rods and hypers with trick flow heads and 292 comp cam, and untuned it ran 12.3 in a heavy monte ss