Not Ranked
Jim,
The Blue Thunder dual plane intake with some port work and divider work on a 289 will pretty much offer the same performance as a single plane up to about 6500 rpm or so. So will a Performer RPM.
Those higher end dual plane intakes actually do extremely well with balancing low/mid range torque with higher end horsepower.
I always push my customers that have to stay with the period correct intakes to choose the dual plane intake. The guys that get to choose whatever they want will usually get a single plane piece. When possible, I'd rather use the extra cost for the Webers and apply them towards other ways of making horsepower or making things more reliable. For instance, on one 289, I used a new crank, had the rod journals turned down to small journal SBC size, then used a 5.700" connecting rod. That little engine produced 390 lb-ft of torque. I also used titanium valves with very low spring pressure for durability and reliability. For the $4-5k extra that you pay for the Webers, you can funnel money into other beneficial areas.
The rules are all over the place for these classes. The 289 that I mentioned in the paragraph above was for a customer in the UK and he was not allowed to use roller rockers, so I had some factory rockers REM polished and cryogenically treated and we paired those with a solid flat tappet.
|