Is there a bee hive valve spring available for the V 6 that you do not have to machine the block ??

Is there more power from the V6 with running roller tip performance lifter on just the exhaust ?? just the intake ?? or has using the set for both intake and exhaust been best..

I have an extra set of heads I will start with the bare heads and precision port..I will cut gages so the ports are uniform and all bowls are equal,, I will replace all parts in the valve train with new ..I plan on using 1.52 roller tip!! but am interested in a roller rocker set if it can benefit MPG..

I am interested in top fuel economy with torque & horse power following closely

My outstanding gains from the detailed exhaust manifold porting & exhaust plumbing modifications have given me hope after 10 other disasters !! ha ha

good chance you can find a CompCams "Beehive" spring which fits
look up the specs, or even just call them and ask which of their Beehive designs matches their 980-12 springs
or, find a spring which matches the specs, and machine down the spring perch to fit the spring

roller tips - dont bother unless full rocker. and do them all, not just the intakes or exhausts. sometimes people will use the 1.7 ratio rockers on just the intake or exhaust to create more lift without a cam change - but just using 1.52's on just intake or exhaust make no change.

If you're using a 2.8/3.1/3.4, you can use the new 26981s, they're good to .525" lift from an installed height of 1.700", and give about 110 psi on the seat. If you're using a 3.8, then go with a set of 26915s