BBC piston and ring questions
#1
BBC piston and ring questions
Scuffed 3 pistons in one motor, pretty sure I know what happened. Another story for another day. I am going to most likely put new rods and pistons in both motors.
454's .030 over, cureently 8.9:1. Replacing with flat top forged (prob probe) pistons. 088 heads Should equal 8.4:1 roughly.
B&m 420 megablowers with chillers about 6lbs of boost. Mild hyd flat tappet cam.
What should I run for piston to wall clearance ? Was thinking .0055-.0065?
What ring package should I go with? 1/16 or 5/64?
Thanks
454's .030 over, cureently 8.9:1. Replacing with flat top forged (prob probe) pistons. 088 heads Should equal 8.4:1 roughly.
B&m 420 megablowers with chillers about 6lbs of boost. Mild hyd flat tappet cam.
What should I run for piston to wall clearance ? Was thinking .0055-.0065?
What ring package should I go with? 1/16 or 5/64?
Thanks
#2
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stay away from probe,,look nice but?? i have seen problems with them on some race motors..some of the pistons were.003 off from each other..stick with J&E or srp..worse case ross also makes a great piston..also spend the money on total seal rings..
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I am Refreshing my 540's right now... Daryl from Nortech did the machine work to my blocks and set the piston to wall at .006" with the 2618 JE pistons.
I was told by Daryl to use .026/.028 ring gaps... .0026 to .003" Bearing Clearance
Mine is supercharged and I am adding chillers and boost this time!! Also switched it from a solid flat tappet cam to a hyd roller.
I was told by Daryl to use .026/.028 ring gaps... .0026 to .003" Bearing Clearance
Mine is supercharged and I am adding chillers and boost this time!! Also switched it from a solid flat tappet cam to a hyd roller.
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Go with some JE blower pistons. Really not much more than the SRP line, I think I paid about 650 a set for mine. The pin they come with will work just fine for your setup.
If your on a tight budget, go with the JE Blower piston and a good set of Speed Pro file fit plasma Moly rings or Childs and Albert. Total seals are nice, but carry a nice price tag. id rather go that route than a cheaper piston and total seal rings. File Fit plasma moly been working just fine for many years. Just be sure the ring gaps are set to spec and proper honing is done.
Hell Fire rings are bad a$$, but wouldnt use them on a production block. They will wear the bores before they wear themselves. I'd rather keep the bores and lose a few hp. It just wont matter in a 40ft boat anyway.
If your on a tight budget, go with the JE Blower piston and a good set of Speed Pro file fit plasma Moly rings or Childs and Albert. Total seals are nice, but carry a nice price tag. id rather go that route than a cheaper piston and total seal rings. File Fit plasma moly been working just fine for many years. Just be sure the ring gaps are set to spec and proper honing is done.
Hell Fire rings are bad a$$, but wouldnt use them on a production block. They will wear the bores before they wear themselves. I'd rather keep the bores and lose a few hp. It just wont matter in a 40ft boat anyway.
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They had a retarded huge cam in the engine, the engine was losing 2-3 pounds of boost easy with that cam. I am putting a Crane 651 cam in. The Crane cam will tighen things up and bump the boost... I will play with the pulleys until it makes 7-8lbs with the chillers!
Maybe next winter I can do dry sump 6's if these Konrads dont like my new engines!!