I was woundering if i would gain much HP and torque if i just changed out the crank and rods on my setup without changing anything else.I was thinking the 4.140 or 4.300 either with the 6.800 rods.And if so which crank would be better to go with.

my current setup is KB138 pistons 22cc dish,comps X4262H XTREME 4x4 cam,ported dove heads,stealth intake,770 truck avenger carb,straight up timing chain, recurved duraspark distributer, and a d1VE block .060 over.


thanks kevin

 

You have to change the pistons too, since they use a different pin dia. and hieght for the longer stroke, and rod combo.
Will it make a difference yes it will, you would be suprised, personally I would go with the 4.3 stroke it's a nice setup and really doesn't have too many issues to deal with for clearencing (actually mine dropped right into the block without clearencing anything)
What you will find though is the increase of over 60cid will melllow whatever cam you have out A LOT but you will probably gain atleast that in HP (60 that is) without any other changes. And will have a good increase in torque depending on what else you do.

 

what pistons would you recomend with this combo to have around 10 to1 compression ratio if i use the 4.3.My block hasnt been decked or heads milled.

 

you hve a couple of good choices for use with the 4.3 crank but before I get to those srp makes them for the 4.14 crank but no option for the .060 over bore you have to go .030 or .080
Now another option is Probe but with the same issue only offered in .030 or .080 so you would have to bore it again but probably not a totally bad idea to get it right, and get a good seal on the rings.
these are for .080 over
6.7" rod part number 12330-080 yields a 10.67:1
6.8" rod part number 13599-080 yeilds a 10.28:1

another option is Diamond and you can get these in .060 or .080 over but for use with a 6.8" rod only (the 6.8 is a better choice IMHO)
.060 over part number 40227
.080 over part number 40225
both yeild a 9.6:1, and all comp ratios are for 76cc head which is nominally right for a DOVE head

if you want to go with diamond call Eric up there since he is back, and great to work with. Diamond doesn't stock these pistons as a shelf piston but can make them as needed, and no they aren't considered custom pistons with the associated price and might actually have them in stock
I believe the probe pistons are shelf stock but not for sure.

 

Thanks for the help ill check on the diamond pistons my block is a fresh bore nothing installed yet and ill still be able to go .080 down the road if i need it plus i like their compression ratio a little better the others are a little to close for me.