Thread: Need some advice

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Originally Posted by 1gary

Pat,when you go to the 6.125 or more yep you can get into ring problems,but with the buttons that are out there,it is a non issue.Anything under a 6.0,you can get good results.Remember,almost all stroker kits use a 5.7 rod for a good reason.The others are even longer.Non are the 400 size.

i built alot of 4.250 some4.500 and 4.375 cranks and 4.750 soon a 5.500 crank engines buttons are not going to help much if you have a stacked ring pack and the 2 ring needs to run thru pin center so at that point a shorter rod. i was telling the guy at oliver rod about the mccarthy rule it states the rod should be 2 inch longer then the stroke and your good i never seen a 400 blow up from short rods

we have probably only seen 2 or 3 people order 5.7 rods--almost all the sbc guys want 6 inchers--with a stroker for a standard deck height SBC, the 6 in rods gives a good crank counter weight, and on a stroke that will clear a standard base circle cam they will work with either a ring spacer on the oil ora tight ring package.

with the longer strokes--we have ready to go balanced 3.875 strokers with 6 in rods and a short deck Mahle piston---these long rod, stroker pistons are extremely lite and will result in a bob weight in the mid 1600 grams range requiring NO heavy metal for an internal balance.

Originally Posted by pat mccarthy

i built alot of 4.250 some4.500 and 4.375 cranks and 4.750 soon a 5.500 crank engines buttons are not going to help much if you have a stacked ring pack and the 2 ring needs to run thru pin center so at that point a shorter rod. i was telling the guy at oliver rod about the mccarthy rule it states the rod should be 2 inch longer then the stroke and your good i never seen a 400 blow up from short rods

Nope-no 400's blew up due to rod lengths.But your going way,way,on the other end of what I was suggesting.5.500 crank???.Holy Crow!!!!.Well then you set your clock with those rev's of the crank throws I guess.

I do think it helps leverage of the crank with longer rods.

With everything you do there are trade offs.There are pros and cons.With this link you will see in the chart a ideal rod ratio of 1.75(I think that was it)

http://victorylibrary.com/mopar/rod-tech-c.htm

But I think getting back to the original poster's question is important.My two cents is for him to take his 2 grand and apply that towards a stroker kit and add a good set of heads at a later date.

1.75 is nice if you can get it but its B.S i seen many 1.45 and know of a 1.35 engine that gets Nos and we bet it would not make one run thats was over 5 years ago. i built and have look at long v short rods built some bbc both ways . as for sbc the last 383 street blower engine i used a 5.7 rod . i look at more then just the rod on a build . the ch of piston were the ring pack how far down can i start the ring pack . what size rings i can use in the ring pack . do i need to park the oil ring in the pistons pin bore . if used at lower speed and more for street .as for my 5.500 crank and my ti rods my mass is as lite 2221 grams .you want to place bets that it will run and it will have a life to it as well .i take it out on nice warm dry days getting the mass down plays a roll to. i talk to some on longer rods my first long rod engine i did over 17 years ago when the counter weigth s were not in the best place and every thing was custom made rods. pistons . you could buy shelf cranks . now day s its come along way every thing is made for just about evey thing you can think of cranks most of the time only need two chunks of heavy metal to go internal if any. were you needed alot more of heavy metal with some of the older cranks .all i saying is if it fits i try to use the longest rod s in the engine if that work s on what the engine build is going to be used for

ok going with a 350 bored 30 over and a good kit from summit with dart heads that will produce about 9.8 to 1 compression. I believe that will get me close to 400 hp . with a good rv cam for tork !!