Currently building a 434 sbc. Is there a rod that will clear the cam lobe with out grinding on the rod. 700 lift cam. Mowtown block not a raised cam block
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Currently building a 434 sbc. Is there a rod that will clear the cam lobe with out grinding on the rod. 700 lift cam. Mowtown block not a raised cam block
Using a 4" crank in std. height block. I have talked to guys that have been lucky not needing clearance but I have never been. Need stroker clearanced rods and a small base circle ( .900 ) camshaft to begin with and you still may need to clearance. Lunati Pro Mod and Scat pro series I beam rods have a lot of clearance. You still may have to advance or retard the camshaft to get the clearance you need. Check rods 1,2,5 and 6 closely for clearance. You can use a zip tie of about .050 to check clearance.
If it were me, I would be looking at a big bore short stroke deal, not that huge long stroke heavy crank, that will be a bear to get clearances in that block
3-3/4 max stroke.
I have a 3-5/8 stroke motor and a 3-7/8. both 4.125 or slightly bigger bore
both 15 degree. I like the 3-5/8 motor better
But a lot depends on what you are putting it in, head combination, class of car, and weight of car.
I know they say no replacement for displacement, but sometimes I disagree with that.
If you need a raised cam wide rail block in iron, I am currently running one, would like to sell to get weight off nose of car...lol
What length you using Jim?
He could run a 3.875 crank in that block without all the clearance issues with the right rods. You wouldnt even notice the 13 cubic inches you give up and it is way easier.
Like JustAddDirt said depends on the class you are running also. If you are traction limited, like a modified, the over-square or big bore / short stroke deal is more forgiving. That big 4" crank is going to make a TON of torque to try to hook. Good luck which ever way you decide to go.
this is what i try to sell to my customers all the time , which we usually use the 3.850 stroke , but some folks will not hear it because some one out ran them with a 434 , and that must be it...lol....but i tell them , hey , its only money and we will do what ever you want and can afford.....Quote:
Originally Posted by hpontap
So .50 cam clearance is minimal? Building motor for dirt late model. Previous motor was a 372. Motown heads 2.02/ 1.60. That i built for a street stock with same Motown block. Went bigger cuz I was getting out motored. I have got all the 434 rotating assembly. Small cicrle base can from bullet cams.. Running alochol now with cnc ported dart pro 1
I have never had any issues with as little as .035 but I like to use.050 as a rule of thumb.
You are using the 227 cc heads ? Should be a lot more the 372 you had.
Take your calipers and find a plastic zip tie with the thickness you are comfortable with and use that to gauge the clearance. Easy to get in there and doesnt mar anything. Be sure to check a few degrees on either side of your cam lobes when checking.
Yes the 227 heads
Small base circle cams are prone to breaking with all that spring pressure. I would make it on the maintenance list after each refresh if you keep running it.