- Joined
- Apr 19, 2011
- Messages
- 4,308
- Reaction score
- 64
- Location
- San Jose, CA
- My Car
- 1971 M-code Grande
Around seven months ago we installed a rebuilt never fired 351C 4V
quench long block purchased from Don of OMS. We had all the parts
including the original iron intake and a Holley 80670 with vacuum
secondaries. The only difference between the old block (cracked)
and the new block is a cam we measured at 0.58 lift. That is
not stock. My Holley came with three springs; black, silver and
yellow. Silver is installed for "most" applications with black being
used when you want the secondaries to come off later for better
gas mileage. The yellow spring is soft producing better acceleration
at lower RPM. My mechanic says...... if there is a noticeable increase
in performance using the softer spring, I need a bigger carb.
mike
quench long block purchased from Don of OMS. We had all the parts
including the original iron intake and a Holley 80670 with vacuum
secondaries. The only difference between the old block (cracked)
and the new block is a cam we measured at 0.58 lift. That is
not stock. My Holley came with three springs; black, silver and
yellow. Silver is installed for "most" applications with black being
used when you want the secondaries to come off later for better
gas mileage. The yellow spring is soft producing better acceleration
at lower RPM. My mechanic says...... if there is a noticeable increase
in performance using the softer spring, I need a bigger carb.
mike