Bronze Lifter Bores
 

When do you have to use bronze lifter bores? i have a merlin 111 10.2 deck BBC with dart big m heads. the cam has 833 thou lift and 900lb open

Bronze lifter bores....
 

Hello, Bronze lifter bores are always a good idea in an "all-out" racing engine. The benefits include: truing the lifter bores to proper alignment and angle, reduced friction, the option of larger O.D. lifters and repairability of the lifter bore in the event of lifter failure. This can be performed by most reputable machine shops but it can be expensive. This is a smart procedure if you want to protect the investment of the cylinder block/engine but it is not absolutely necessary. Most racing engine companys do this now to protect the buyers investment anyway, because of increased horsepower and limitations on valvetrain it is more cost effective to spend the added time to install the bushings at the time the engine is assembled from new.

i think its also a machining work to fix a older wore motor that you want to keep, you can also sleeve a block thats is past the limitsof regular use to "save" a old friend"-lol but it is costly , great for vintage engines

Re: Bronze Lifter Bores
 

We CNC machine alot of blocks and rarely install bronze bushings only when bushings back to std. to ge the lifter bores in the correct locations as most guys go with either .875 or .904 to correct lifter bore alignment ans going wit the bigger lifter like the .904 lifter give you more surface area and less wear if any.

We have 2 SBC with 871's on them and aluminum blocks with .904 lifters and no bushings and we run 1250 over the nose and 460at the seat and no wear issues using the aluminum lifter bores.